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Cold Spring Harbor Laboratory

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Michael Schatz. Photo courtesy of Cold Spring Harbor Laboratory

By Daniel Dunaief

What if an enormous collection of Scrabble letters were spread out across the floor? What if several letters came together to form the word “victory”? Would that mean something? On its own, the word might be encouraging, depending on the context.

Genetic researchers are constantly looking at letters for the nucleotides adenine, guanine, cytosine and tyrosine, searching for combinations that might lead to health problems or, eventually, diseases like cancer.

For many of these diseases, seeing the equivalent of words like “cancer,” “victory” and “predisposition” are helpful, but they are missing a key element: context.

W. Richard McCombie

Michael Schatz, an adjunct associate professor at Cold Spring Harbor Laboratory who is also the Bloomberg distinguished associate professor at Johns Hopkins, and W. Richard McCombie, a professor at Cold Spring Harbor Laboratory, use long-read sequencing technology developed by Pacific Biosciences to find genetic variants that short-read sequencing missed.

The two scientists recently teamed up to publish their work on the cover of the August issue of the journal Genome Research. They provided a highly detailed map of the structural variations in the genes of a breast cancer cell.

“This is one of many covers [of scientific journals] that we are pleased and proud of,” said Jonas Korlach, the chief scientific officer at Menlo Park, California-based Pacific Biosciences. 

“This is another example of how long-read sequencing can give you a more complete picture of the genome and allow researchers to get a more complete understanding of the underlying biology and here, specifically, that underlies the transition from a health to a cancer disease state,” he said.

Schatz and McCombie were able to see fine detail and the context for those specific sequences. They were able to see about 20,000 structural variations in the cancer genome. “It’s like using Google maps,” explained Schatz in a recent interview. “You can see the overall picture of the country and then you can see roads and zoom out.”

In the context of their genetics work, this means they could see large and small changes in the genome. Only about a quarter of the variants they found could be detected without long-read technology.

In breast cancer, scientists currently know about a family of genes that could be involved in the disease. At this point, however, they may be unaware of other variants that are in those genes. Schatz is hoping to develop more sensitive diagnostics to identify more women at risk.

People like actress and advocate Angelina Jolie have used their genetic screens to make informed decisions about their health care even before signs of any problems arise. Jolie had a double mastectomy after she learned she had the mutation in the BRCA1 gene that put her at an 87 percent risk of developing breast cancer.

By studying the sequence of genes involved in breast cancer, researchers may be able to identify other people that are “at high risk based on their genetics,” Schatz said.

Knowing what’s in your genome can help people decide on potentially prophylactic treatments. 

When people discover that they have breast cancer, they typically choose a specific type of treatment, depending on the subtype of cancer.

“There’s a lot of interest to divide [the genetic subtypes] down into even finer detail,” said Schatz, adding, “There’s also interest in transferring those categories into other types of cancer, to give [patients] better treatments if and when the disease occurs.”

The reduced cost of sequencing has made these kinds of studies more feasible. In 2012, this study of the breast cancer genome would have cost about $100,000. To do this kind of research today costs closer to $10,000 and there’s even newer sequencing technology that promises to be even less expensive, he said.

Pacific Biosciences continues to see a reduction in the cost of its technology. The company plans to introduce a new chip next year that has an eightfold higher capacity, Korlach said.

Schatz said the long-term goal is to apply this technique to thousands of patients, which could help detect and understand genetic patterns. He and McCombie are following up on this research by looking at patients at Northwell Health.

In this work, Schatz’s group wrote software that helped decipher the code and the context for the genetic sequence.

“The instrument doesn’t know anything about genes or cancer,” he said. “It produces raw data. We write software that can take those sequences and compare them to the genome and look for patterns to evaluate what this raw data tells us.”

Schatz described McCombie, with whom he speaks every day or so, as his “perfect complement.” He suggested that McCombie was one of the world’s leaders on the experimental side, adding, “There’s a lot of artwork that goes into running the instruments. My lab doesn’t have that, but his lab does.”

Working with his team at CSHL and Johns Hopkins has presented Schatz with numerous opportunities for growth and advancement.

“Cold Spring Harbor is an internationally recognized institute for basic science, while Johns Hopkins is also an internationally recognized research hospital and university,” he explained. He’s living in the “best of both worlds,” which allows him to “tap into amazing people and resources and capacities.”

Korlach has known Schatz for at least a decade. He said he’s been “really impressed with his approach,” and that Schatz is “highly regarded by his peers and in the community.”

Schatz is also a “terrific mentor” who has helped guide the development of the careers of several of his former students, Korlach said.

Down the road, Schatz also hopes to explore the genetic signature that might lead to specific changes in a cancer, transforming it from an organ-specific disease into a metastatic condition.

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Camila dos Santos speaks at the Pershing Square Research Alliance’s Fifth Annual Prize Dinner at the Park Avenue Armory on May 23 with Bill Ackman, co-founder of the Pershing Square Sohn Foundation and CEO of Pershing Square Capital Management, and Olivia Tournay Flatto, the President of the Pershing Square Foundation.

By Daniel Dunaief

They aren’t quite wonder twins, but some day the dedicated work of husband and wife scientists Christopher Vakoc and Camila dos Santos may help people batting against a range of cancers, from leukemia to breast cancer.

An assistant professor at Cold Spring Harbor Laboratory, dos Santos recently won the prestigious and highly coveted Pershing Square Sohn prize. Dos Santos, who studies breast cancer, will receive $200,000 in funds per year for the next three years. She won the same prize her husband, an associate professor at Cold Spring Harbor Laboratory, collected two years earlier for his work using the gene-editing technique CRISPR to study the molecular pathways involved in leukemia.

Dos Santos and Vakoc are the first family of prize winners in the Pershing Square Foundation’s five years of supporting research in the New York area.“The board was very much taken by how original her approach is and how thoughtful she is about it,” said Olivia Tournay Flatto, president of the foundation. “There was a lot of early stage data that would say that the observations she’s making are interesting to pursue, but that the National Institutes of Health would not fund. We felt this was something we wanted to be a part of.”

Dos Santos is studying so-called epigenetic changes that protect women from breast cancer if they become pregnant before they are 25. Women who have pregnancies before that cut-off age have a 30 to 40 percent decrease in breast cancer, even decades after their pregnancy.

Dos Santos has been digging into this process, looking at why some women who are pregnant before this age still develop breast cancer later in life.

The Cold Spring Harbor scientist is exploring how infections block the protective effects of pregnancy. She hasn’t defined the panel of infections that could influence cancer risk before or after pregnancy. The hypothesis in her work is that “the whole process that is fighting inflammation could change the breast cells,” which could “take away the advantage that pregnancy brings.”

If she proves her theory — that changes to inflammation could take away benefits of an early pregnancy — she could define changes to proteins and genes as biomarkers to predict the risk of breast cancer, even in the event of an early pregnancy. One of the challenges in the three-step application process for this prize was to explain to a group of experts how what she’s doing was different from what others are pursuing. Her approach is to look at cells before and during the process of turning into cancer cells. That strategy led to the current hypothesis, which was the basis for her application for this prize.

To study breast cancer, dos Santos recently developed a mouse model in her lab, to see how pregnancy changes pre-malignant lesions. When the mice they are studying have a gene that would turn into cancer, some of them don’t develop cancer if they’ve already been pregnant. Those mice that haven’t been pregnant develop cancer. She uses this mouse model to ask questions about how pregnancy changes a cell such that oncogenes cannot operate to change a cell into a cancer.

“We are not only investigating how prevention works, but we are also learning what signals break that prevention,” dos Santos said.

Dos Santos has used the mouse model experiments to test an unusual element to human breast cancer resistance. Women who reach their second trimester before 25, but don’t give birth to a child, have the same resistance, decades later, to breast cancer. Mice whose pregnancies last through the equivalent of the second trimester also experience similar epigenetic benefits.

She has tested mice who have a pseudo-pregnancy —who have higher pregnancy hormone levels without being pregnant — to see if a similar pregnancy environment would convey the same resistance. “Even in those cases, with no fetus, no embryo, no birth and no nursing, we see that the epigenetics changes,” dos Santos said. The scientist plans to use the funds from this award to perform high-tech experiments, such as single-cell, multiple mouse models and human tissue analysis that she wouldn’t have been able to tackle without the funding.

Dos Santos is grateful for the funding, which she said she wouldn’t have been able to secure through other means based on “the stage we are right now,” she said. The work is “risky” and “provocative,” but it’s also “outside of the box ideas and experiments and approaches.”

When she puts all the variants together, the risky outcome could be beneficial, leading to a better understanding of how to copy or, perhaps, understand nature to try to cure or prevent cancer.

Dos Santos said she learned about the award when she was on a train on the way to Jamaica, where she was catching a flight to Washington, D.C. She said she turned into a “texting machine,” sharing the good news with everyone, including her husband Vakoc, who called her as soon as he saw the news. “He was super happy,” she recalled.

She said Vakoc was particularly helpful in discussing the work and in watching their sons Lucas and Marcus who are 8 and 5, respectively. She also received some unexpected help from him before an extensive seven- to eight-minute finalist screening process.

She asked him about the interview, and he remembered that there were five people in the audience and that he didn’t get that many questions. When she appeared for her interview, she saw about 25 people in the audience and received numerous questions. In a way, she said, his memory of his experience may have helped her, because she didn’t have time to worry about the size of the audience or the number of questions.

Dos Santos said their sons are proud of their parents for winning awards for their work on cancer.

When her sons are upset with dos Santos, they sometimes warn, reflecting their parents’ threat to take away TV, that they’re going to “take your epigenetics away.”

Dos Santos said the couple maintains a healthy work-life balance. She is grateful for her husband’s support, as well as for the environment and expertise at Cold Spring Harbor Laboratory.

“Here at the lab, we not only have the technology to move this forward, but we also have a pretty outstanding body of scientists that are very collaborative,” she said.

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Hervé Tiriac during a recent visit to the University of Nebraska Cancer Center. Photo by Dannielle Engel

By Daniel Dunaief

What if doctors could copy human cancers, test drugs on the copies to find the most effective treatment, and then decide on a therapy based on that work?

Hervé Tiriac, a research investigator at Cold Spring Harbor Laboratory, moved an important step closer to that possibility with pancreatic cancer recently.

Tiriac, who works in the Cancer Center Director Dave Tuveson’s lab, used so-called organoids from 66 patients with pancreatic ductal adenocarcinoma tumors. These organoids reacted to chemotherapy in the same way that patients had. 

“This is a huge step forward,” Tiriac said, because of the potential to use organoids to identify the best treatments for patients.

Hervé Tiriac. Photo by Dannielle Engel

Tuveson’s lab has been developing an expertise in growing these organoids from a biopsy of human tumors. The hope throughout the process has been that these models would become an effective tool in understanding the fourth most common type of cancer death in men and women. The survival rate five years after diagnosis is 8 percent, according to the American Cancer Society.

The study, which was published in the journal Cancer Discovery, “shows real promise that the organoids can be used to identify therapies that are active for pancreatic cancer patients,” Tuveson explained in an email. “This may be a meaningful advance for our field and likely will have effects on other cancer types.”

Kerri Kaplan, the president and CEO of the Lustgarten Foundation, which has provided $150 million in financial support to research including in Tuveson’s lab, is pleased with the progress in the field.

“There’s so much momentum,” Kaplan said. “The work is translational and it’s going to make a difference in patients’ lives. We couldn’t ask for a better return on investment.”

Tiriac cautions that, while the work he and his collaborators performed on these organoids provides an important and encouraging sign, the work was not a clinical trial. Instead, the researchers retrospectively analyzed the drug screening data from the organoids and compared them to patient outcomes.

“We were able to show there were parallels,” he said. “That was satisfying and good for the field” as organoids recapitulated outcomes from chemotherapy.

Additionally, Tiriac’s research showed a molecular signature that represents a sensitivity to chemotherapy. A combination of RNA sequences showed patterns that reflected the sensitivity for the two dominant chemotherapeutic treatments. “It was part of the intended goal to try to identify a biomarker,” which would show treatment sensitivity, he said.

While these are promising results and encourage further study, researchers remain cautious about their use in the short term because several technical hurdles remain.

For starters, the cells in the organoids take time to grow. At best right now, researchers can grow them in two to four weeks. Drug testing would take another few weeks.

That is too slow to identify the best first-line treatment for patients with advanced pancreatic cancer, Tiriac explained. “We have to try to see if the organoids could identify these biomarkers that could be used on a much shorter time frame,” he added.

Tuveson’s lab is working on parallel studies to accelerate the growth and miniature the assays. These efforts may reduce the time frame to allow patients to make informed clinical decisions about their specific type of cancer.

As for the RNA signatures, Tiriac believes this is a first step in searching for a biomarker. They could be used in clinical trials as is, but ideally would be refined to the minimal core gene signatures to provide a quick and robust assay. It is faster to screen for a few genes than for hundreds of them. He is studying some of these genes in the lab.

Researchers in Tuveson’s lab will also continue to explore biochemistry and metabolism of the organoids, hoping to gain a better insight into the mechanisms involved in pancreatic cancer.

Going forward, Tiriac suggested that his main goal is to take the gene signatures he published and refine them to the point where they are usable in clinical trials. “I would like to see if we can use the same approach to identify biomarkers for clinical trial agents or targets that may have a greater chance of impact on the patients,” he said.

The research investigator has been working at Tuveson’s lab in Cold Spring Harbor since the summer of 2012.

Tuveson applauded Tiriac’s commitment to the work. Without Tiriac’s dedication, “there would be no Organoid Profiling project,” Tuveson said. “He deserves full credit for this accomplishment.”

Tiriac lives in Huntington Station with his wife Dannielle Engle, who is a postdoctoral researcher in the same lab. He “really enjoyed his time on Long Island,” and suggested that “Cold Spring Harbor has been a fantastic place to work. It’s probably the best institution I’ve worked at so far.”

He appreciates the chance to share the excitement of his work with Engle. “You share a professional passion with your loved one that is beyond the relationship. We’re able to communicate on a scientific level that is very stimulating intellectually.”

Born in Romania, Tiriac moved to France when his family fled communism. He eventually wound up studying in California, where he met Engle.

Tuveson is appreciative of the contributions the tandem has made to his lab and to pancreatic cancer research. 

“Although I could not have imagined their meritorious accomplishments when I interviewed them, [Tiriac and Engle] are rising stars in the cancer research field,” he said. “They will go far in their next chapter, and humanity will benefit.”

Kaplan suggested that this kind of research has enormous potential. “I feel like it’s a new time,” she said. “I feel very different coming into work than I did five years ago.”

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What do the signs tell us?

In Hawaii, numerous small earthquakes caused parts of Big Island to shake. Geologists, who monitor the islands regularly, warned of a pending volcanic eruption. They were right, clearing people away from lava flows.

How did they know?

It’s a combination of history and science. Researchers in the area point to specific signs that are reflections of patterns that have developed in past years. The small earthquakes, like the feel of the ground trembling as a herd of elephants is approaching in the Serengeti, suggest the movement of magma underneath the ground.

Higher volumes of lava flows could come later on, as in 1955 and 1960, say USGS scientists in the archipelago.

The science involves regular monitoring of events, looking for evidence of what’s going on below the surface. “Hopefully we’ll get smart enough that we can see [tremors] coming or at least be able to use that as a proxy for having people on the ground watching these things,” Tina Neal, scientist-in-charge at USGS Hawaiian Volcano Observatory, explained to KHON2 News in Honolulu.

People look for signs in everything they do, hoping to learn from history and to use whatever evidence is
available to make predictions and react accordingly.

Your doctor does it during your annual physical, monitoring your blood chemistry, checking your heart and lungs, and asking basic questions about your lifestyle.

Scientists around Long Island are involved in a broad range of studies. Geneticists, for example, try to see what the sequence of base pairs might mean for you. Their information, like the data the geologists gather in
Hawaii, doesn’t indicate exactly what will happen and when, but it can suggest developments that might affect you.

Cancer researchers at Cold Spring Harbor Laboratory and Stony Brook University are using tools like the gene editing system called CRISPR to see how changing the genetic code affects the course of development or the pathway for a disease. Gene editing can help localize the regions responsible for the equivalent of destructive events in our own bodies, showing where they are and what sequences cause progression.

Scientists, often working six or seven days a week, push the frontiers of our ability to make sense of
whatever signs they collect. Once they gather that information, they can use it to help create more accurate diagnoses and to develop therapies that have individualized benefits.

Indeed, not all breast cancers are the same, which means that not all treatments will have the same effect. Some cancers will respond to one type of therapy, while others will barely react to the same treatment.

Fundamental, or basic, research is critical to the understanding of translational challenges like treating
Alzheimer’s patients or curing potentially deadly fungal infections.

Indeed, most scientists who “discover” a treatment will recognize the seminal studies that helped them finish a job started years — and in some cases decades — before they developed cures. Treatments often start long before the clinical stages, when scientists want to know how or why something happens. The pursuit of knowledge for its own sake can lead to unexpected and important benefits.

Outside the realm of medicine, researchers on Long Island are working on areas like understanding the climate and weather, and the effect on energy production.

Numerous scientists at SBU and Brookhaven National Laboratory study the climate, hoping to understand how one of the most problematic parts of predicting the weather — clouds — affects what could happen tomorrow or in the next decade.

The research all these scientists do helps us live longer and better lives, offering us early warnings of
developing possibilities.

Scientists not only interpret what the signs tell us, but can also help us figure out the right signs to study.

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Gholson Lyon. Photo courtesy of Cold Spring Harbor Laboratory

By Daniel Dunaief

With the cost of determining the order of base pairs in the human genome decreasing, scientists are increasingly looking for ways to understand how mutations lead to specific characteristics. Gholson Lyon, an assistant professor at Cold Spring Harbor Laboratory, recently made such a discovery in a gene called NAA15.

People with mutations in this gene had intellectual disability, developmental delay, autism spectrum disorder, abnormal facial features and, in some cases, congenital cardiac anomalies.

In a recent interview, Lyon explained that he is trying to understand how certain mutations influence the expression of specific traits of interest, such as intelligence, motor development and heart development. He’s reached out to researchers scattered around the world to find evidence of people who had similar symptoms, to see if they shared specific genetic mutations in NAA15 and found 37 people from 32 families with this condition.

“I really scoured the planet and asked a lot of people about this,” said Lyon, who recently published his research in The American Journal of Human Genetics. The benefit of this kind of work, he explained, is that it can help screen for specific conditions for families at birth, giving them an ability to get an earlier diagnosis and, potentially, earlier treatment. “Being able to identify children at birth and to know that they are at risk of developing these disorders would, in a perfect world” allow doctors to dedicate resources to help people with this condition, he said.

Lyon published a similar study on a condition he named Ogden syndrome seven years ago, in which five boys in a single family died before they reached the age of 3. A mutation in a similar gene, called NAA10, led to these symptoms, which is linked to the X chromosome and was only found in boys.

Lyon found the genes responsible on NAA15 by comparing people with these symptoms to the average genome. The large database, which comes from ExAC and gnomAD, made it possible to do a “statistical calculation,” he said. The next steps in the research is to look for protein changes in the pathway in which these genes are involved. The people he studied in this paper are all heterozygous, which means they have one gene that has a mutation and the other that does not.

With this condition, they have something called haploinsufficiency. In these circumstances, they need both copies of the fully functioning gene to produce the necessary proteins. These mutations likely decrease the function of the protein. Lyon would like to study each of these cases more carefully to understand how much the mutation contributes to the various conditions. He looked for evidence of homozygous mutations but didn’t find any. “We don’t know if they don’t exist” because the defective gene may cause spontaneous miscarriages or if they just didn’t find them yet, he said.

Lyon plans on reaching out to geneticist Fowzan Alkuraya, who was trained in the United States and is working at King Faisal Specialist Hospital and Research Centre clinic in Saudi Arabia. The geneticist has studied the genes responsible for a higher rate of genetic disorders linked to the more common practice of people having children with cousins in what are called consanguineous marriages. 

Alkuraya works on the Saudi Human Genome Program, which studies the inherited diseases that have a higher incidence in Saudi Arabia.

For Lyon, finding the people who carry this mutation was challenging, in part because it hasn’t run in the family for multiple generations. Instead, Lyon and his colleagues, including Holly Stessman of Creighton University in Omaha, Nebraska and Linyan Meng at Baylor College of Medicine in Houston, Texas, found 32 unrelated families. In some of these families, one or two siblings carried this mutation in a single mutation.

By defining a new genetic disease, the scientists could help families seeking a diagnosis, encourage the start of early intervention such as speech therapy and connect patients with the same diagnosis. This can provide a support network in which people with this condition and their families know they are not battling this genetic challenge alone, Meng, the assistant laboratory director at Baylor Genetics and assistant professor at Baylor College of Medicine, explained in an email.

Every patient with an NAA15 mutation won’t have the same symptoms. “We see a range of phenotypes in these patients, even though they carry the same diagnosis with defects in the same disease,” Meng added. “Early intervention could potentially make a difference for NAA15 patients.”

Lyon works as a psychiatrist in Queens providing medication management. During his undergraduate years at Dartmouth College, in Hanover, New Hampshire, Lyon said he was interested in neurology and psychology. As he went through his residency at NYU, Columbia and New York State Psychiatric Institute, he gravitated toward understanding the genetic basis of autism, which he said is easier than conditions like schizophrenia because autism is more apparent in the first few years of life.

Lyon recently started working part time at the Institute for Basic Research in Developmental Disabilities on Staten Island. While Lyon appreciates the opportunity to work there, he is concerned about a potential loss of funding. “These services are vital” on a clinical and research level, he said. He is concerned that Gov. Andrew Cuomo (D) is thinking about decreasing the budget for this work. Reducing financial support for this institution could cause New York to lose its premiere status in working with people with developmental disabilities, he said.

“It has this amazing history, with an enormous number of interesting discoveries in Down syndrome, Alzheimer’s disease and Fragile X,” he said. “I don’t think it gets enough credit.”

As for his work with NAA, Lyon plans to continue to search for other people whose symptoms are linked to these genes. “I am looking for additional patients with mutations in NAA10 or NAA15,” he said.

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First Row from Left to Right: Kapeel Chougule, Computational Science Developer II; Mariana Neves Dos Santos Leite, Lab Aide (no longer at CSHL); Sharon Wei, Computational Science Analyst II; Andrew Olson, Computational Science Analyst II Second Row from Left to Right: Joshua Stein, Computational Science Manager III; Christos Noutsos, Postdoctoral Fellow (no longer at CSHL); Vivek Kumar, Computer Scientist; Doreen Ware, CSHL Adjunct Associate Professor & USDA/ARS Research Scientist; Yinping Jiao, Post Doc Computational; Sunita Kumari, Computational Science Analyst III; Marcela Tello-Ruiz, Computational Science Manager II; Young Koung Lee, Post Doc 11; Jerry Lu, Computational Science Developer III; Michael Regulski, Research Investigator Third Row from Left to Right: Christophe Liseron-Monfils, Post Doc Computational (no longer at CSHL); Bo Wang, Post Doc Computational; Liya Wang, Computational Science Manager III; Joseph Mulvaney, Computational Science Analyst III (no longer at CSHL); Lifang Zhang, Research Associate; James Thomason, Computational Science Developer III; Peter Van Buren, Systems Engineer III Not Pictured but in Ware Lab: Nicholas Gladman, Post Doc III; Fangle Hu, Research Technician II; Demitri Muna, Computational Science Analyst III; Pragati Muthukumar, Lab Intern, High School; Xiaofei Wang, Computational Science Analyst I; George Wang, Lab Intern, College; Christy Bedell, Senior Scientific Administrator. Photo by William Ware

By Daniel Dunaief

In a two-month span, members of Doreen Ware’s lab at Cold Spring Harbor Laboratory have published three articles that address fundamental properties of plants. 

Doreen Ware. Photo by Gina Motisi, Cold Spring Harbor Laboratory

Printed in the journal Nature Genetics, researchers in her lab studied the genes involved in conferring disease resistance across a range of species of rice. Another study, featured in Nature Communications, found the genes and the molecular pathway that determines the number of fertile flowers in the cereal crop sorghum.

In Frontiers in Plant Science, her productive team identified the causal genes that enable sorghum to develop a waxy outer layer that allows it to resist drought by containing water vapor.

 

“I am pleased with the recent publications from the laboratory,” Ware, who is also a computational biologist for the U. S. Department of Agriculture, explained in an email. “This is a sign of productivity, as well as the impact [technological] advances and drop in sequencing [costs] that is supporting these science advancements.”

Her lab is interested in the link between the genes in a plant and the way it develops.

“I want to understand mechanistically how the outputs in a genome interact with one another to produce a product,” Ware said. This will allow the lab to inform breeding models. “We would like to use the biological mechanism to support predictive modeling.”

In the rice article, Ware, informatics manager Joshua Stein at Cold Spring Harbor Laboratory and University of Arizona plant scientist Rod Wing searched for the specific genetic sequences different species of rice around the world use to develop resistance to infections by fungi, bacteria and other pathogens.

They used wild varieties of rice that had not been domesticated and looked for signals in the DNA. These were selected by their collaborators based on phenotypes that may be of value to introduce into domesticated varieties.

Stein looked at rice in areas including Asia, Africa, South America and Australia. Through this analysis, he was able to focus on specific genetic sequences that helped these species survive local threats.

As a first step, Stein explained, they have identified all of the genes in these species, but do not yet know which are important for local adaption. This article could provide information on the region of the genome that had disease genes that have been successful over time against threats in the environment.

One potential route to reducing dependency on pesticides is to introduce natural resistance or tolerance. By providing multiple ways of defending itself, a plant can reduce the chance that a pathogen can overcome all of these defenses.

“This is a similar strategy that is used to address both viral diseases and cancer treatment,” Ware explained.

Boosting the defenses of some of these crops with genes that have worked in the past is one strategy toward sustainability, although the scientists would need to work on the specifics to see how they were deployed.

Stein explained that his role in this specific study was to annotate the genes by using computer programs to look at DNA sequences. Stein used a process called comparative genomics, in which he studied the genes of numerous species of rice and compared them to look for similarities and differences.

“Because these different species grow in different climates and geographical ranges, they will be locally adapted to those regions,” Stein said. “Those genes might be important to improve cultivated rice.”

As climates change and people and materials such as seed crops move around the world, rice may need to develop a resistance to a bacteria or fungi it hasn’t encountered much through its history. Indeed, even those species of rice that haven’t moved to new areas may face threats from new challenges, such as insects, fungi, bacteria and viruses, that have moved into the area.

By understanding successful adaptive strategies, researchers like Ware and Stein can look for ways to transfer these defenses to other rice varieties.

Stein likens the process to an arms race that pits pathogens against food crops. “There are real examples of where a resistance gene has been transferred from a wild species to a cultivated species using traditional approaches,” he said. This includes knocking out specific genes in wheat that provide powdery mildew resistance.

Ware’s lab also produced an article in which they explored the genetic pathway that tripled the grain number of sorghum. The grain is produced on the panicle, which has many branches. In a normal plant, more than half of the flowers are not fertile, producing fewer grains.

“We have recently published a paper on a variety of sorghum where nearly all of the flowers are fertile, increasing the grain number on each head,” said Ware.

The work was led by Yinping Jiao and Young Koung Lee, postdoctoral researchers in Ware’s lab. Jiao focused on the computational analysis while Lee explored the development.

The researchers reduced the level of a hormone, which generated more flowers and more seeds. Other researchers could take a similar approach to boost yield in other grain crops.

Employing a commonly used technique to introduce new variation to support trait development, Department of Agriculture plant biologist Zhanguo Xin created a new variant that resulted in a change in a protein. This plant had a lower level of the hormone jasmonic acid in the developing flower. The researchers believe a reduction in the activity of a transcription factor that controls gene regulation caused this.

“We are currently exploring if this is associated with a direct or indirect interaction with biosynthetic genes required to make the plant hormone,” Ware said.

Early in January, Ware’s lab also produced a study in which they used mutations in sorghum to reveal the genetic mechanism that enables the plant to produce a wax that helps with its drought resistance.

Ware suggested these studies are linked to an underlying goal. “In human health, genomics and mechanism support the development of management of disease and in some cases cures,” she explained. “In agriculture, it leads to improved germplasm development and sustained agriculture.”

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From left, Jason Sheltzer, Nicole Sayles (who is a former lab technician and a co-author of an earlier MELK paper) and SBU undergraduates Chris Giuliano and Ann Lin. Photo by Constance Brukin

By Daniel Dunaief

If eating macaroni and cheese made Joe sick, he might conclude he was allergic to dairy. But he could just as easily have been allergic to the gluten in the macaroni, rendering the dairy-free diet unnecessary.

Scientists try to connect two events, linking the presence of a protein, the appearance of a mutation or the change in the metabolic activity of a cell with a disease. That research often leads to targeted efforts to block or prevent that protein. Sometimes, however, that protein may not play as prominent a role as originally suspected. That is what happened with a gene called MELK, which is present in many types of cancer cells. Researchers concluded that the high level of MELK contributed to cancer.

Jason Sheltzer, a fellow at Cold Spring Harbor Laboratory, and Ann Lin and Christopher Giuliano, undergraduates at Stony Brook University who work in Sheltzer’s lab, proved that wasn’t the case. By rendering MELK nonfunctional, Sheltzer and his team expected to block cancer. When they knocked out MELK, however, they didn’t change anything about the cancer, despite the damage to the gene. But, Sheltzer wondered, might there be some link between MELK and cancer that he was missing? After all, scientists had found a drug called OTS167 that was believed to block MELK function.

To test this drug’s importance for MELK and cancer, Sheltzer used this drug on cancer cells that didn’t have a functioning MELK gene or protein. Even without MELK, the drug “killed cancer cells,” regardless of the disappearance of a gene that researchers believed was important for cancer’s survival, he said.

“We showed for the first time that [the drug] was killing cells that didn’t express MELK,” Sheltzer said. The drug had to have another, unknown target.

Sheltzer suggested that this is the first time someone had used CRISPR, a gene-editing technique, to take a “deep dive” into what a drug is targeting. This drug, he said, has a different mechanism of action from the one most people believed.

Sheltzer, whose work was published in early February in eLife, expanded the research from a petri dish, where researchers grow and study cells, to mouse models, which are often more similar to the kinds of conditions in human cancers. In those experiments, he found no difference between the tumors that grew with a MELK gene and those that didn’t have the MELK protein, continuing to confirm the original conclusion. “The tumors that formed in cells that had MELK and the tumors that formed in cells that didn’t have MELK were the same size,” he said.

Originally, Sheltzer believed the MELK protein might be involved in chemotherapy resistance. His lab found, however, that no matter what they did to MELK in these cells, the cancer appeared indifferent. Other researchers suggested that Sheltzer’s work would be instructive in a broader way for scientists.

Sheltzer’s research on MELK “will motivate a new set of standards for target discovery and validation in the field going forward,” Christopher Vakoc, an associate professor at CSHL, explained in an email. Sheltzer “brings a rigorous approach to cancer research and an impressive courage to challenge prevailing paradigms.” Sheltzer’s work highlights the challenge of understanding the mechanism of action of new medicines, Vakoc added.

Sheltzer plans to explore several other genes in which a high concentration of a specific protein coded by that gene correlates with a poor prognosis.

Using CRISPR, Sheltzer believes his lab can get precise information about drug targets and their effect on cancer. He’s also tracing a number of other types of cancer drugs that he thinks might have compelling properties and will use CRISPR to study the action of these drugs. “We want to know not just that a drug kills cancer cells: We want to know how and why,” he said.

By figuring out what a drug targets, he might be able to identify the patients who are most likely to respond to a particular drug. So far, the finding that a drug doesn’t work by interfering with a specific gene, in this case MELK, has been easier than finding the gene that is the effective target, he explained.

One of Sheltzer’s goals is to search for a cancer cell that is resistant to the drug, so that he can compare the genes of the vulnerable one with those of the cell that’s harder to treat. Detecting the difference in the resistant cell can enable him to localize the region critical for a drug’s success.

Sheltzer said finding that MELK was not involved in a cancer’s effectiveness was initially “depressing” because researchers believed they had found a cancer target. “We hope that by publishing these techniques and walking through the experiments in the paper that other labs can learn from this and can use some of the approaches we used to improve their drug discovery pipelines,” he said.

Sheltzer is pleased that Lin and Giuliano made such important contributions to this paper. CRISPR has made it possible for these undergraduates to “make these really important discoveries,” he said. Lin, who has worked in Sheltzer’s lab for two and a half years, was pleased. “It is very exciting to share my knowledge of MELK in regards to its role in cancer biology,” she wrote in an email. “Authoring a paper requires a great deal of work and I am super thrilled” to see it published.

Sheltzer, who lives with his partner Joan Smith, who is a software engineer at Google, said he was interested in science during his formative years growing up in Wayne, Pennsylvania, which is just outside of Philadelphia, and appreciates the position he has at Cold Spring Harbor Laboratory. Soon after earning his doctorate at MIT, Sheltzer set up his own lab, rather than conducting research for several years as a postdoctoral researcher. “I was really fortunate to be given that opportunity,” he said.

As for his work with MELK, Sheltzer hopes he’s saved other labs from pursuing clinical dead ends.

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Yali Xu and Christopher Vakoc at the 2013 Don Monti Memorial Research Foundation’s Anniversary Ball. Photo from Yali Xu

By Daniel Dunaief

It’s like a top scorer for another team that the greatest minds can’t seem to stop. Whatever they throw at it, it seems to slip by, collecting the kinds of points that can eventually lead to a life-threatening loss. The scorer is a transcription factor called MYB, and the points it collects can, and often do, lead to breast and colon cancer and leukemia.

Researchers have known for over 30 years that stopping MYB could help with cancer treatment. Unlike other possible targets, however, MYB didn’t seem to have the kind of structural weakness that pharmaceutical companies seek, where developing a small molecule could prevent the cancer signals MYB delivered. Some researchers have decided that drugs won’t stop this high-profile cancer target.

Cold Spring Harbor Laboratory Associate Professor Christopher Vakoc and his graduate research assistant Yali Xu, however, have figured out a way around this seemingly intractable problem. The CSHL scientists recently published their results in the journal Cancer Cell.

MYB binds at a small nub to a large and important coactivation protein called TFIID (which is pronounced TF-two-D). This protein is involved in numerous life functions and, without it, organisms couldn’t survive. Vakoc and Xu found that they could use a small peptide decoy to trick MYB into believing it had attached to this protein when, it reality, it hit the equivalent of a molecular dead end.

In a mouse model of acute myeloid leukemia, this peptide caused leukemias to shrink in size by about 80 percent. “What we’ve discovered is head and shoulders above anything we’ve come across before,” Vakoc said.

As with many scientific discoveries, researchers have to clear numerous hurdles between this conceptual discovery and any potential new cancer therapy. “This is not a medicine a person can take,” Vakoc said.

Indeed, scientists and pharmaceutical companies would need to study what leukemia cells escaped this type of treatment to understand how a cancer might rebound or become resistant after an initial treatment. “Our goal is to develop something with longer lasting effects” that doesn’t become ineffective after three to six months, Vakov said. He described understanding the way a disease reacts to a treatment as an “arms race.” Nature inevitably “finds a way to outsmart our decoy. We’d like to know how [it] does it. We’re always trying to study both sides and trying to anticipate” the next steps.

Down the road, Vakoc could foresee researchers and, ultimately, physicians using this kind of approach in combination with other drugs or therapies, the way doctors now provide patients who have the HIV infection with a cocktail of drugs. Conceptually, however, Vakoc is thrilled that this work “highlights what’s possible.”

One of the most encouraging elements of this approach, Vakoc said, is that it combats MYB without harming organ systems. When the researchers gave the treatment to rodents, the mice were “running around, eating and gaining weight.” Their body tissues appeared normal, and they didn’t demonstrate the same sensitivity that is a common byproduct of chemotherapy treatment, such as losing any hair or having problems in their gut.

An important step in this study, Vakoc said, was to understand the basics of how MYB and TFIID found each other. That, Xu said, was one of the first steps in her graduate work, which took about five years to complete.

In Vakoc’s lab, which includes 13 other researchers, he described how scientists make thousands of perturbations to cancer and normal cells, while they are hunting for cancer-specific targets. By using this screening technique, Vakoc and his team can stress test how cancer cells and normal cells react when they are deprived of certain proteins or genes.

“This began as a screen,” he said. “We took leukemia and normal blood cells and did a precise comparison of the perturbation.” They searched for what had the most specific toxicity and, to their surprise, found that interfering with the binding between MYB and TFIID had the strongest effect. “Once we understood what this nub was doing, we applied all kinds of biochemical assay experiments,” Vakov added.

Ultimately, the peptide they found was a fragment of a larger protein that’s active in the cell. Vakoc credits Xu for her consistent and hard work. “When we started on this hunt, we had no idea where this was headed,” he said. Xu was “relentless” in trying to find the answers. “She pieced it all together. It took a great amount of imagination and intellect to solve this puzzle.”

Vakoc suggested that Xu, who plans to defend her thesis this spring and graduate this summer, has set a great example for the other members of his lab. “I now have 13 other people inspired to outdo her work,” he said. “We know we have a new standard.”

Xu is grateful for the support she has received from Vakoc and appreciates the journey from her arrival as a graduate student from China to the verge of her graduation. “It’s very satisfying when you look back and think how things evolved from the beginning to the end” of her graduate work, said Xu, who lives near Huntington Village and enjoys the chance to visit local restaurants and sample coffee and ice cream when she isn’t conducting research toward her doctorate.

The scientific effort, which was published recently, has attracted the attention of others, particularly those who are studying MYB. Vakoc recently received an email from members of a foundation that is funding research on a solid tumor in which scientists believe MYB plays a role. He is writing grants to get more financial support to pursue this concept. Vakoc is encouraged by the opportunity to make progress with a protein that has been “staring [scientists] in the face for three decades.”

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Alexander Krasnitz. Photo by Gina Motis?CSHL

By Daniel Dunaief

Seeing into the future is one of the most challenging, and potentially rewarding, elements of studying cancer. How, scientists and doctors want to know, can they take what evidence they have —through a collection of physical signs and molecular signatures — and determine what will be?

Researchers working on a range of cancers have come up with markers to divide specific types of cancers to suggest the likely course of a disease.

With prostate cancer, the medical community uses a combination of the prostate-specific antigen (PSA), magnetic resonance imagining (MRI) and biopsy results, which are summarized as the Gleason score, to diagnose the likely outcome of the disease. This analysis offers probable courses for developing symptoms.

Cold Spring Harbor Laboratory Professor Michael Wigler and Associate Professor Alexander Krasnitz recently published an article in the journal Cancer Research of a promising study of eight patients that suggests a way of using molecular signatures to determine whether a prostate is likely to contain cells that will threaten a patient’s health or whether the cells are in a quieter phase.

The third most common cancer among Americans, prostate cancer kills an average of 21,000 men each year. Doctors and their patients face difficult decisions after a prostate cancer diagnosis.

“A major challenge is to determine which prostate cancers have aggressive potential and therefore merit treatment,” Herbert Lepor, a professor and Maritin Spatz Chair of Urology at the NYU Langone Medical Center School of Medicine, explained in an email. A collaborator on the study, Lepor provided a clinical perspective and shared patient samples.

A conversation with a doctor after such a diagnosis may include a discussion about how the cancer is not likely to pose an immediate risk to a patient’s life, Krasnitz explained. In that case, doctors do not recommend surgery, which might cause other problems, such as incontinence.

Doctors typically recommend active surveillance to monitor the disease for signs of progression. Some patients, however, make their own decisions, electing to have surgery. The Gleason score, which is typically 3, 4 or 5, can’t provide “meaningful information regarding aggressiveness of the disease,” Lepor explained. “The unique genetic profile of a cancer cell should have infinite more prognostic capability.”

Wigler and Krasnitz, who have been collaborating since Krasnitz arrived at CSHL in 2005, use several hundred single cells from biopsy cores. The research group, which Krasnitz described as a large team including research investigator Joan Alexander and computational science manager Jude Kendall, look for cells with a profile that contains the same irregularities.

“If you take two cells and their irregularities are highly coincident, then perhaps these two cells are sisters or cousins,” Krasnitz explained in an email. “If they are less coincident, then the two cells are more like very distant relatives. We looked for, and sometimes found, multiple cells with many coincident irregularities. This was our evidence for a clonal population.”

By looking at how many biopsy cores contain clonal cells, and then determining how far these clonal cells have spread out through the prostate, the researchers gave these patient samples a score. In this group, these scores, determined before any intervention, closely tracked a detailed analysis after surgery.

“We get a high correlation” between their new score and a more definitive diagnosis that comes after surgery, Krasnitz said. “Our molecular score follows the final verdict from the pathology more closely than the pathological score at diagnosis from the biopsy.”

Wigler, Krasnitz, Lepor and other researchers plan to continue to expand their work at Langone to explore the connection between their score and the course of the disease. Lepor explained that he has been collaborating with Wigler and Krasnitz for five years and suggested this is “an exceptional opportunity since it bridges one of the strongest clinical programs with a strong interest in science (NYU Urology) and a world-class research program interested in clinical care (CSHL).

The research team has submitted a grant to the National Institutes of Health and hopes to expand their studies and provide “compelling evidence” that single-cell genomic mapping “will provide an unmet need defining aggressiveness of prostate cancers,” Lepor said.

While Krasnitz is encouraged by the results so far, he said the team has work ahead of them to turn this kind of analysis into a diagnostic tool physicians can use with their patients.

Realistically, it could take another five years before this score contributes to clinical decision-making, Krasnitz predicted. “You can’t do it overnight,” he cautioned. When this test offers specific signals about the likely outcome for a patient, a researcher would likely need to wait several years as the patient goes on active surveillance to see whether the score has predictive value for the disease in a larger population.

Krasnitz has a sense of urgency to produce such a test because there is “no point in delaying something that potentially looks promising and that one day might well be a part of a clinical practice.”

The work that led to their article took three or four years to complete. The study required technical improvements in the way the researchers processed DNA from single cells. They also had to develop algorithmic improvements that allowed them to use copy number variation to determine clonal structure. The scientists tapped into a wealth of information they gained by taking cells from several locations within the prostate.

Krasnitz was born in Kiev, now part of the Ukraine, and grew up in the former Soviet Union. A resident of Huntington, he lives with his wife Lea, who produces documentaries, including “Maria — The Russian Empress” on Dagmar of Denmark, who was also known as Maria, mother of Nicholas II, the last Romanov czar who was overthrown in 1917. As for his work with Wigler, Krasnitz is excited about the possibilities. “It’s very encouraging,” he said. “We look forward to a continuation of this.”

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Pavel Osten. Photo by Joelle Wiggins

By Daniel Dunaief

Male mice, as it turns out, might also be from Mars, while female mice might be from Venus. Looking at specific cells in the brain of rodents, Cold Spring Harbor Laboratory Associate Professor Pavel Osten has found some noteworthy differences in their brain cells.

In the scientific journal Cell, Osten presented data that showed that in 10 out of 11 subcortical regions of the mouse brain, female mice showed greater flexibility and even more cells. These regions of the brain are responsible for reproduction, and social and parenting behaviors. “There were more cells [in these regions] in the female brain, even though the brains tended to be bigger in the males,” Osten said.

These results are part of a multiyear collaboration called the National Institutes of Health’s Brain Initiative Cell Census Network.

In the recent Cell article, Osten indicated that his analysis offered a surprising result in the number of cells of specific types in various regions of the cortex. “Those areas that have higher cognitive functions have different compositions,” he said. The ratios of cell types “vary according to the level of cognitive function.” In retrospect, Osten indicated that he saw the logic in such a cellular organization. “It makes sense that different cortical areas would have different cell type composition tuned to the specific cortical functions,” he explained.

In an email, Hongkui Zeng, the executive director of structured science at the Allen Institute for Brain Science, in Seattle, Washington, suggested that “people never looked at this issue carefully before. She added that the “sexual dimorphism was somewhat expected, but it is still interesting to see the real data.”

Pavel Osten sailing in St. Barts and St. Martin last summer. Photo from Pavel Osten

Osten used a system called qBrain to see and count inhibitory neurons in the mouse brain. Over the next five years, he and his collaborators will build an online resource database for other researchers that will have distribution maps for numerous cell types throughout the mouse brain.

Osten estimates that there could be hundreds or even a thousand cell types within the brain that are largely uncharacterized in their specialized functions. A cell type is defined by its function in terms of its morphology, including dendritic and axonal branches. These cells are also defined by their physiology, which includes spiking properties, and connectivity, which indicates which cell is talking to other cells.

The anatomy and physiology of the cells will validate these transcriptome single-cell RNAseq studies, which probe for the variability between cells based on their gene expression, which includes differences due to day-to-day variability and differences from distinct cell types.

By analyzing the location and modulatory functions of these cell types, Osten would like to determine ways human brains differ from other animal brains. “In the human, we can mainly analyze the location and distribution which includes the ratios of specific cell types and our hypothesis is that fine-tuning the ratios of neuronal cell types may be a powerful evolutionary mechanism for building more efficient circuits and possibly even for distinguishing between human and other animals,” Osten explained in an email.

Humans, he continued, don’t have the largest brains or the most neurons. At one point, spindle neurons were considered unique to humans, but other researchers have shown that great apes, elephants and cetaceans, which is a group that includes whales and dolphins, also have them.

Osten’s hypothesis is that one of the differences is that the ratios of cells of different types built a computational circuit that’s more powerful than the ones in other species.

When he studies mouse brains, Osten collects information across the entire brain. With humans, he explores one cubic centimeter. The human work is just starting in his lab and represents a collaboration with Zsófia Maglóczky from the Hungarian Academy of Sciences at the Institute of Experimental Medicine in Budapest.

Each mouse brain dataset is between 200 gigabytes and 10 terabytes, depending on the resolution Osten uses to image the brain. He can process 10 terabytes of data in about a week.

Osten uses machine learning algorithms that develop with guidance from human experts. This comes from a long-standing collaboration with Sebastian Seung, a professor of computer science at Princeton University.

He suggested that the research has a translational element as well, offering a way to study cellular and wiring elements characteristic of diseases. “We are looking at several of the models that are well established for autism.” He is also planning to write grants to find funds that supports the analysis of brains from people with schizophrenia and Alzheimer’s disease.

The analysis is a promising avenue of research, other scientists said. “It will be extremely interesting to compare the ratio of different cell types in various diseased brains with normal healthy brains, to see if the diseases may preferentially affect certain cell types and why and how,” Zeng explained in an email. “This could be very helpful for us to devise therapeutic means” to treat diseases.

Zeng has known Osten for about seven years. Last year, she began a collaboration using qBrain to quantify cell types.

A current resident of Williamsburg, where his reverse commute is now about 40 minutes, Osten works with a company he and Seung started called Certerra, which provides a rapid analysis of brain activity at different times. The company, located in Farmingdale, has a growing customer base and has a staff of about five people.

As for the recent work, researchers suggested it would help continue to unlock mysteries of the brain. This research is “a basic but important step toward understanding how the brain works,” Zeng added. “This paper provides a new and efficient approach that will be powerful when combined with genetic tools that can label different cell types.”

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