2019 News

Highly Cited Researchers

Raul Rabadan Highly Cited
Raul Rabadan, PhD, (standing) with Francesco Brundu, postdoctoral research scientist in the Rabadan lab (Credit: Jeffrey Schifman)

Congratulations to Drs. Raul Rabadan and Xuebing Wu who were recently named a Highly Cited Researcher, according to the 2019 list from the Web of Science Group . Overall, Columbia University ranked 15th on the list of global institutions, with a total of 47 Highly Cited Researchers.

The Highly Cited Researchers list, which was released Nov. 19,  identifies scientists and social scientists who have produced multiple papers ranking in the top 1% by citations for their field and year of publication, demonstrating significant research influence among their peers.

Xuebing Wu, PhD
Xuebing Wu, PhD

Dr. Rabadan is professor of systems biology , with a joint appointment in biomedical informatics, at Columbia’s Vagelos College of Physicians and Surgeons . At Columbia, the Rabadan lab consists of an interdisciplinary team developing mathematical and computational tools to extract useful biological information from large data sets. In 2017, Dr. Rabadan established the Program for Mathematical Genomics , a multidisciplinary research hub that brings together researchers from the fields of mathematics, physics, computer science, engineering, and medicine, with the common goal of solving pressing biomedical problems through quantitative methods and analyses. He also serves as program lead for the Cancer Genomics and Epigenomics Program at the Herbert Irving Comprehensive Cancer Center at NYP/Columbia. 

Videos of flies (5x speed) using FlyWalker, a program that enables scientists to label and track the position of each of the fly’s footfalls, thereby building a high-resolution picture of it’s walking gait. Top: normal fly walking at around 25 mm/s. Bottom: fly with its VNC serotonin neurons stimulated, which slows its speed to 15 mm/s (Credit: Clare Howard/Mann lab/Columbia's Zuckerman Institute)

A Columbia University study in fruit flies has identified serotonin as a chemical that triggers the body’s startle response, the automatic deer-in-the-headlights reflex that freezes the body momentarily in response to a potential threat. Today’s study reveals that when a fly experiences an unexpected change to its surroundings, such as a sudden vibration, release of serotonin helps to literally — and temporarily — stop the fly in its tracks.

These findings, recently published in Current Biology , offer broad insight into the biology of the startle response, a ubiquitous, yet mysterious, phenomenon that has been observed in virtually every animal studied to date, from flies to fish to people.

“Imagine sitting in your living room with your family and — all of a sudden — the lights go out, or the ground begins to shake,” said Richard Mann , PhD, a principal investigator at Columbia’s Mortimer B. Zuckerman Mind Brain Behavior Institute and the paper’s senior author. “Your response, and that of your family, will be the same: You will stop, freeze and then move to safety. With this study, we show in flies that a rapid release of the chemical serotonin in their nervous system drives that initial freeze. And because serotonin also exists in people, these findings shed light on what may be going on when we get startled as well.”

In the brain, serotonin is most closely associated with regulating mood and emotion. But previous research on flies and vertebrates has shown it can also affect the speed of an animal’s movement. The Columbia researchers’ initial goal was to more fully understand how the chemical accomplished this.

Congenital diaphragmatic hernia (CDH) is a severe birth defect. For babies born with CDH, their diaphragms are not developed properly, with some or all parts of the abdominal organs pushed into the chest. The displacement of these critical organs can have a significant impact on how the lungs develop and grow. 

Dr. Yufeng Shen
Yufeng Shen, PhD, associate professor of systems biology

A recent study , led by Yufeng Shen , PhD, and Wendy Chung , MD, PhD, and their labs at Columbia University Irving Medical Center , investigated the genetic risk factors linked to CDH and analyzed data from whole genome sequencing and exome sequencing to determine novel mutations. The study also uncovered the link between CDH and additional developmental disorders. 

“Many babies with this birth defect also have lung hypoplasia or pulmonary hypertension and babies have difficulty breathing. Even with advanced care available, the mortality rate is still about 20 percent,” says Dr. Shen, associate professor of systems biology at Columbia, with a joint appointment in the Department of Biomedical Informatics

“One hypothesis is that the lung condition is not necessarily caused by the physical compression on the developing lungs in the chest,” explains Dr. Shen, “it can be caused by the same genetic defect that causes CDH. Finding those genes is absolutely necessary to improve care and develop effective treatment in the long run.”   

Scientists have been aiming to identify new risk genes in CDH—and other developmental disorders—with  the hope that with improved genetic diagnosis more tailored or long-term care for patients born with this defect could be provided, as well as potential targets for intervention down the road. 

Nicholas Tatonetti, PhD
Nicholas Tatonetti, Phd

Nicholas Tatonetti , PhD, solves problems. He has always enjoyed it, and as the informatics community has discovered, he is both creative and proficient in his methods.

Dr. Tatonetti, who was recently awarded tenure and promoted to the rank of Associate Professor in the Columbia Department of Biomedical Informatics (DBMI) and Department of Systems Biology , focuses on the use of advanced data science methods, including artificial intelligence and machine learning, to investigate medicine safety. Using emerging resources, such as electronic health records (EHR) and genomics databases, his lab is working to identify for whom these drugs will be safe and effective and for whom they will not.

His path to Columbia wasn’t a traditional one, but that fits his work. Since joining in 2012, Dr. Tatonetti has used non-traditional thinking to benefit both health and healthcare.

Utilizing both data mining of medical records and prospective lab experiments, Dr. Tatonetti created a methodology for both finding and validating adverse drug reactions and drug-drug interactions. During a two-year collaboration with Pulitzer Prize-winning journalist Sam Roe of the Chicago Tribune , Dr. Tatonetti discovered that the drugs ceftriaxone and lansoprazole, when taken together, induces an arrhythmia in the heart.

The data mining identified adverse effects, while the lab experiments established causality. Dr. Tatonetti wasn’t specifically looking for a negative reaction of those particular drugs; he had no reason to suspect them.

“We are able to find things that nobody expects to happen because the world of hypotheses we consider is basically everything,” he said. “We consider every possible combination, a type of analysis that would be impossible without a huge data set and significant computational power.”

As a member of Columbia University’s Program for Mathematical Genomics (PMG) , Tal Korem, PhD, is bringing his interests in systems biology, quantitative research, and the human microbiome to areas of clinical relevance. For Dr. Korem, that clinical focus is women’s reproductive health. 

“There is still a lot we don’t understand that relates to women’s health, to fertility, and to birth outcomes, and how microbes play a role in all of this,” says Dr. Korem, assistant professor of systems biology, with a joint appointment in obstetrics and gynecology at Columbia University Vagelos College of Physicians and Surgeons. A current focus of the Korem lab is preterm birth, i.e., birth that occurs prior to 37 weeks of gestation, though Dr. Korem intends to expand into other areas such as infertility and endometriosis. 

Tal Korem, PhD
Tal Korem, PhD

Dr. Korem’s interest in  women’s health research is personal, stemming from several impactful experiences that hit close to home. 

“My aunt passed away from ovarian cancer and I have seen friends and family members struggle with idiopathic infertility,” he says. “Also, witnessing the complications with the birth of my first child, which involved emergency procedures, motivated my interest in this area, and I am very excited about the potential to contribute to women’s health with my own research.” 

Dr. Korem, a native of Tel Aviv, Israel, is the first in his family to earn a PhD, and had entered academia as a medical student. After completing  his undergraduate degree, he enrolled in a MD/PhD graduate program. There, he realized that research was what he enjoyed the most. He is a trained computational biologist, and studied under Professor Eran Segal at the Weizmann Institute of Science, where his work focused on the  human microbiome, a complex system of microbial communities that inhabit every body part. 

A wide range of research topics, from studies related to pediatric cancer and glioblastoma to soil microbial communities and electronic health records analysis—were presented and discussed at this year’s Department of Systems Biology (DSB) retreat. 

DSB Retreat 2019
Eugene Douglass, postdoctoral research scientist in the Andrea Califano lab, was one of the featured presenters at the two-day retreat. For a photo gallery, view the DSB Retreat Photo Album.

Held over two days for the first time, October 3 to 4 in Ellenville, NY, the retreat gave DSB faculty, post-docs, and students a chance to get away from the bustle of New York City, learn about their peers’ research, both from Morningside labs and CUIMC labs, and network. The department this year expanded its annual program over two days, encouraging more peer-to-peer connecting and devoted the spotlight specifically to research by young investigators. 

DSB researchers and graduate students participated in a poster competition held the first evening, and reviewed by Systems Biology faculty judges. At the end of the second day’s program, three Best Poster winners were announced by Andrea Califano, Dr, chair of the department. Poster competition winners this year were: Dafni Glinos , PhD, postdoctoral researcher in the lab of Dr. Tuuli Lappalainen at New York Genome Center/Systems Biology; Alexander Kitaygorodsky , a graduate student in the lab of Dr. Yufeng Shen; and Jordan Metz , an MD/PhD graduate student in the lab of Dr. Peter Sims. The poster winners gave presentations on the final day of the retreat and received a cash prize and an award certificate. 

Winning Research:

Dafni Glinos

Long-Read Sequencing to Study Allelic Effects on Transcriptome Structure

Dr. Tuuli Lappalainen Science Study

The illustration above depicts with an example of four genes, how knowing how variable genes are in the normal population helps to find candidate disease genes in a patient. Above, top: Tuuli Lappalainen, PhD; bottom: Pejman Mohammadi, PhD.

For individuals with rare diseases, getting a diagnosis is often a long and complicated odyssey. Over the past few years, this has been greatly improved by genome sequencing that can pinpoint the mutation that breaks a gene and leads to a severe disease. However, this approach is still unsuccessful in the majority of patients, largely because of our inability to read the genome to identify all mutations that disrupt gene function.

In a new study published on October 10 in Science , researchers from New York Genome Center , Columbia University , and Scripps Research Institute propose a solution to this problem. Building a new computational method for analyzing genomes together with transcriptome data from RNA-sequencing, they can now identify genes where genetic variants disrupt gene expression in patients and improve the diagnosis of rare genetic disease.

The new method introduced in this study, Analysis of Expression Variation or ANEVA, first takes allele-specific expression data from a large reference sample of healthy individuals to understand how much genetic regulatory variation each gene harbors in the normal population. Then, using the ANEVA Dosage Outlier Test, researchers can analyze the transcriptome of any individual – such as a patient – to find a handful of genes where he or she carries a genetic variant with an unusually large effect compared to what healthy individuals have. By applying this test to a cohort of muscle dystrophy and myopathy patients, the researchers demonstrated  the performance of their method and diagnosed additional patients where previous methods of genome and RNA analysis had failed to find the broken genes.

MAGIC - Wang Lab

Illustrated here: (a) In contrast to traditional approaches to cultivate microbes first and then test for genetic accessibility, MAGIC harnesses horizontal gene transfer in the native environment to genetically modify bacteria in situ. (b) MAGIC implementation to transfer replicative or integrative pGT vectors from an engineered donor strain into amenable recipients in a complex microbiome. Replicative vectors feature a broad-host range origin of replication (oriR), while integrative vectors contain a transposable Himar cassette and transposase. The donor E. coli strain contains genomically integrated conjugative transfer genes (tra) and a mCherry gene. Transconjugant bacteria are detectable based on expression of an engineered payload that includes GFP and an antibiotic resistance gene (abr).

A team of researchers, led by Dr. Harris Wang of the Department of Systems Biology , has engineered bacteria to benefit and improve the overall health of our gut microbiome. In a proof-of-concept paper published in Nature Methods , Dr. Wang and his team demonstrate MAGIC, an innovative gene delivery system that ‘hacks’ the gut microbiome to perform any desired function, from harvesting energy from food and protecting against pathogen invasion to bolstering anti-inflammatory properties and regulating immune responses.

“The MAGIC system allows us to insert new gene functions directly into an existing microbiome without permanently altering the composition of the microbiome as a whole,” says Sway Chen , an MD/PhD student in the Wang lab and co-author of the study.

Time lapse of a developing drosophila embryo. (Credit: Carlos Sanchez-Higueras/Hombría lab/CABD)

Every animal, from an ant to a human, contains in their genome pieces of DNA called Hox genes. Architects of the body, these genes are keepers of the body’s blueprints; they dictate how embryos grow into adults, including where a developing animal puts its head, legs and other body parts. Scientists have long searched for ways to decipher how Hox genes create this body map; a key to decoding how we build our bodies.

Now an international group of researchers from Columbia University and the Spanish National Research Council (CSIC) based at the Universidad Pablo de Olavide in Seville, Spain have found one such key: a method that can systematically identify the role each Hox gene plays in a developing fruit fly. Their results, reported recently in Nature Communications , offer a new path forward for researchers hoping to make sense of a process that is equal parts chaotic and precise, and that is critical to understanding not only growth and development but also aging and disease.

“The genome, which contains thousands of genes and millions of letters of DNA, is the most complicated code ever written,” said study co-senior author Richard Mann , PhD, principal investigator at Columbia’s Mortimer B. Zuckerman Mind Brain Behavior Institute and a faculty member in the Department of Systems Biology . “Deciphering this code has proven so difficult because evolution wrote it in fits and starts over hundreds of millions of years. Today’s study offers a key to cracking that code, bringing us closer than ever to understanding how Hox genes build a healthy body, or how this process gets disrupted in disease.”

Read the full article at the Zuckerman Institute

Tal Korem, PhD
Dr. Tal Korem

Tal Korem, PhD, has been named a CIFAR Azrieli Global Scholar, a fellowship that supports leading early-career researchers in science and technology. 

Dr. Korem is an assistant professor of systems biology with a joint appointment in obstetrics and gynecology at Columbia University Vagelos College of Physicians & Surgeons, and a faculty member of the Program for Mathematical Genomics . As a global scholar, he is joining CIFAR’s Humans and the Microbiome research program, where his work will focus on harnessing human microbial communities to identify and develop novel diagnostic and therapeutic tools.

CIFAR’s  Azrieli Global Scholars program supports its fellows through funding and mentorship, emphasizing essential network and professional skills development. The scholars join CIFAR research programs for a two-year period where they collaborate with fellows and brainstorm new approaches to pressing science and technology problems. Research topics are diverse, ranging from bio-solar energy and visual consciousness to engineered proteins and the immune system. 

Dr. Korem is one of 14 researchers out of an applicant pool of 217 selected by the Canadian-based nonprofit organization. This year’s cohort represents citizenship in eight countries and appointments in institutions from Canada, the U.S.,  Israel, Australia, the Netherlands, and Spain.

-Melanie A. Farmer

Sagi Shaipra PHIPSTer Cell Paper
Researchers implement P-HIPSTer, an in silico computational framework that leverages protein structure information to identify approximately 282,000 protein-protein interactions across all fully-sequenced human-infecting viruses (1001 in all). This image highlights that in addition to rediscovering known biology, P-HIPSTer has yielded a series of new findings and enables discovery of a previously unappreciated universe of cellular circuits and biological principles that act on human-infecting viruses. (Image Courtesy of Dr. Sagi Shapira)

Researchers at Columbia University Irving Medical Center have leveraged a computational method to map protein-protein interactions between all known human-infecting viruses and the cells they infect. The method, along with the data that it generated, has spawned a wealth of information toward improving our understanding of how viruses manipulate the cells that they infect and cause disease. Among its findings, the work uncovered a role for estrogen receptor in regulating Zika Virus (ZIKV) infection, as well as links between cancer and the human papillomavirus (HPV).

The research, led by Sagi Shapira , PhD, Assistant Professor in the Department of Systems Biology and the Department of Microbiology & Immunology at Columbia University Vagelos College of Physicians and Surgeons , appears today in the journal, Cell . Dr. Shapira’s collaborators include Professors Barry Honig , PhD, of Systems Biology and of Biochemistry and Molecular Biophysics and Raul Rabadan , PhD, of Systems Biology and of Biomedical Informatics. 

Protein engineering is a relatively young field that creates new proteins never seen before in nature. Today’s protein engineers usually create synthetic proteins by making small changes to the gene that encodes a naturally occurring protein. The variety of synthetic proteins range from stain-removing enzymes that have improved detergents to a long-acting insulin that’s used by millions of people with diabetes.

But two big unsolved challenges for protein engineers remain: The gene encoding the synthetic protein needs to be contained to prevent escape into other organisms and the gene needs to resist mutating over time so the protein doesn’t lose its function.

By merging two genes into a single DNA sequence, Columbia University synthetic biologists have created a method that could prevent human-engineered proteins from spreading into the wild, as well as stabilize synthetic proteins so they don’t change over time. The work, recently published in Science, was developed by Harris Wang, PhD, assistant professor of systems biology, with graduate student, Tomasz Blazejewski and postdoctoral scientist, Hsing-I Ho, PhD. 

In devising the method, the researchers were inspired by overlapping genes in viruses. When two different genes overlap, they occupy the same sequence of DNA. But the genes are read in different frames so that two different proteins are produced.

In overlapping genes, a random mutation in the sequence may not affect one gene, but it’s likely that it will harm the second gene.

“Overlapping genes essentially lock in a specific DNA sequence, and we thought we could exploit this idea for synthetic biology ...Ten years ago, we didn’t have the technology that would make this possible,” says Dr. Wang. “We didn’t have enough sequences in the database to make informed predictions and we didn’t have a way to synthesize long DNA sequences for testing our predictions.”

The gut microbiome–composed of hundreds of different species of bacteria–is a complex community and a challenge for scientists to unravel. One specific challenge is the spatial distribution of different microbes, which are not evenly distributed throughout the gut. A new method developed by the lab of Dr. Harris Wang should help scientists locate and characterize these neighborhoods, which could shed light on how microbes influence the health of their hosts.

Techniques that can identify all species in the gut microbiome only work with homogenized samples (like stool), but methods that preserve spatial information can only cope with a handful of species.

Dr. Wang, assistant professor of systems biology and of pathology & cell biology, and graduate student Ravi Sheth in the Department of Systems Biology, tested the new technique with mice who switched from a low-fat to a high-fat diet. Diet is known to change the abundance of specific bacteria in the gut within days, but the new technique also revealed that the switch caused wholesale changes of microbial neighborhoods.

“Specific regions of bacteria were entirely lost with a switch in diet,” Sheth says. “This was exciting to us as it will give us clues to understanding how that change happens and how the change may impact health.”

Read the full article in the CUIMC Newsroom

The research, titled “Spatial metagenomic characterization of microbial biogeography in the gut,” was published July 22 in Nature Biotechnology.

 

Newly Tenured Faculty
Awarded tenure this year in the Department of Systems Biology, left to right: Dr. Nicholas Tatonetti, Dr. Yufeng Shen, and Dr. Chaolin Zhang.

Congratulations to Drs. Yufeng Shen, Nicholas Tatonetti, and Chaolin Zhang of the Department of Systems Biology, who have been awarded tenure and promoted to associate professor. Their new appointments are effective July 1, 2019. 

Yufeng Shen, PhD

Dr. Shen joined Columbia University Irving Medical Center in 2011 as an Assistant Professor in Systems Biology and Biomedical Informatics. He directs a research group focused on studies of human biology and diseases using genomic and computational approaches. They are developing new methods to interpret genomic variations by machine learning based on biological mechanisms, and using these methods in large-scale genome sequencing studies to identify new genetic causes of human diseases, such as autism, birth defects, and cancer. His group also works on modeling of clonal and transcriptional dynamics of immune cells to improve our understanding of human adaptive immune system under normal and clinical conditions. Dr. Shen serves as an Associate Director of the JP Sulzberger Columbia Genome Center, a member of the Program in Mathematical Genomics, and an adjunct member of Columbia Center for Translational Immunology. 

Nicholas Tatonetti, PhD

Dr. Tatonetti, whose primary appointment is in the Department of Bioinformatics, has an interdisciplinary appointment with both the Departments of Systems Biology and Medicine. Dr. Tatonetti’s lab specializes in advancing the application of data science in biology and health science. His group integrates their medical observations with systems and chemical biology models to not only explain drug effects, but also to gain further understanding of basic biology and human disease.

Dr. Harris Wang of Systems Biology
Dr. Harris Wang is lead PI on a new DARPA-funded project developing novel therapies to counter effects of high-dose ionizing radiation.

Harris Wang, PhD, assistant professor of systems biology at Columbia University Irving Medical Center , is leading a team of experts in radiation research, CRISPR-Cas technologies, and drug delivery on an innovative new project announced June 27 funded by the Defense Advanced Research Projects Agency (DARPA) . The up to $9.5M project focuses on pursuing a therapy to protect the body from the effects of high-dose ionizing radiation, and is part of DARPA's initiative to fund research into new strategies to combat public health and national security threats.

In humans, acute radiation syndrome primarily affects stem cells in the blood and gut, yet existing treatments only help to regenerate blood cells, and only with limited effect. There is no possibility for prophylactic administration of these drugs, and most must be delivered immediately following radiation exposure to provide any benefit. There are no existing medical countermeasures for radiation damage to the gut.

The Columbia team aims to develop an orally delivered programmable gene modulator therapeutic. The multimodal treatment the team envisions would take hold in both the gut and liver, triggering protection and regeneration of intestinal cells, while also inducing liver cells to produce protective cues that trigger the regeneration of blood cells in bone marrow.

Columbia investigators win Chan Zuckerberg Initiative grants to accelerate development of cellular roadmap of the human body.

In two groundbreaking research projects contributing to the Human Cell Atlas, Columbia University scientists are tasked with mapping complete cells in the immune system and the human spine. The global effort is aiming to identify and define every cell type of the human body and create a collection of maps for navigating the cellular basis of human health and disease.

Peter Sims, PhD
Peter Sims, PhD, assistant professor of systems biology

The Columbia teams, which include co-principal investigators from the Department of Systems Biology Drs. Peter Sims and Raul Rabadan , are among the 38 collaborative science teams launching the Chan Zuckerberg Initiative’s (CZI) Seed Networks for the Human Cell Atlas project announced today. The three-year projects, receiving a total of $68 million in award funding by Seed Networks, are collaborative groups that are bringing together expertise in science, computational biology, software engineering, and medicine to support the ongoing progress of the Human Cell Atlas .

Investigating the Immune System + Aging

Dr. Sims, part of an international team including close collaborator Dr. Donna Farber of the Department of Surgery , is combining single-cell sequencing technologies, data analysis, and immunology expertise to better understand how the immune system ages and gain new insights into how human diseases occur. 

Chaolin Zhang
Chaolin Zhang, PhD, associate professor of systems biology

A new study by researchers in Dr. Chaolin Zhang’s lab at Columbia’s Department of Systems Biology details a novel computational method that models how RNA-binding proteins (RBPs) recognize specific sites in the target RNA transcripts, precisely and accurately. The researchers’ findings include identification of entirely new motifs (RNA sequence patterns), and their research in complex RNA regulation contributes to our understanding of the molecular basis of disease and conditions, and down the road, could aid in the development of targeted therapies. 

The study, led by Dr. Zhang, associate professor of systems biology, with senior co-authors Suying Bao, PhD, and Huijuan Feng, PhD, appears today in Molecular Cell

RNA has traditionally been considered mere “messengers” that transfer genetic information from DNA to proteins that ultimately carry out cellular functions. However, it is now increasingly appreciated that RNA can be tightly regulated to control gene expression and diversity protein products. RNA-binding proteins (RBPs) are at the center of such regulation, with important roles in many cellular processes, including cell function, transport, and location. Gaining mechanistic insights of the binding specificity of RBPs in a genome-wide scale helps advance our knowledge of gene regulation.

“RNA-binding proteins are crucial for gene expression,” says Dr. Feng, coauthor of the study and post-doctoral research scientist in the Zhang lab. “RNA is heavily regulated, and when this regulation goes wrong, instabilities or disease could occur.”  

Dr. Andrea Califano sits down with BioTechniques at AACR. Video: Courtesy of BioTechniques.

At the 2019 annual meeting of the American Association for Cancer Research (AACR), Dr. Andrea Califano sat down with BioTechniques News for an overview on the field of systems biology and its impact in cancer research and in precision medicine. Dr. Califano is a pioneering researcher in the fast-growing field of systems biology whose expertise is in developing innovative, systematic approaches to identify the molecular factors that lead to cancer progression and to the emergence of drug resistance at the single-cell level. A physicist by training, Dr. Califano is the Clyde and Helen Wu Professor of Chemical and Systems Biology, founding chair of the Department of Systems Biology at Columbia University Irving Medical Center, director of the Columbia Genome Center and a program leader at the Herbert Irving Comprehensive Cancer Center.

The video interview is part of the series, Behind the Technqiue by BioTechniques News. 

Oxytricha

New research by Laura Landweber, PhD, who has joint appointments in the Department of Biochemistry and Molecular Biophysics, the Department of Systems Biology and the Department of Biological Sciences at Columbia University, is being featured by Columbia Univeristy Iriving Medical Center Newsroom.

As reported, a new study of a single-celled eukaryote with 16,000 tiny chromosomes may shed light on a recently discovered feature of the human genome.

Methyladenine, or 6mA—a modification of DNA common in Oxytricha trifallax—has only recently been found in multicellular organisms, with some studies suggesting a role in human disease and development.

Finding the enzymes that lay down the methyl marks will be critical to understanding what 6mA is doing in Oxytricha and other organisms, but the enzymes have been difficult to identify.

The new research—to be published in the June 13 issue of Cell—reveals how 6mA marks are made to the Oxytricha genome and suggests why the enzymes have been hard to find.

Read more about the Oxytricha genome and the Landweber lab’s new insights into 6mA and its potential role in human diseases.

Dr. Landweber has been studying Oxytricha for two decades and previously uncovered its 16,000 chromosomes. (See related Faculty Q+A and video.)

 

 

Tuuli Lamport Research Award

Tuuli Lappalainen, PhD, was honored with the Lamport Research faculty award at the 2019 Commencement ceremony. Dr. Lappalainen is pictured here with Columbia University Trustee Andrew Barth (left) and Dean Lee Goldman of Columbia University Irving Medical Center. (Courtesy of CUIMC Communications)

Tuuli Lappalainen , PhD, assistant professor of systems biology at Columbia University and core faculty member at the New York Genome Center (NYGC) , has received the Harold and Golden Lamport Research award, presented on May 22 at the Vagelos College of Physicians and Surgeons Commencement Ceremony. 

The Lamport Research award is an annual prize given to junior faculty members that show promise in basic science or clinical science research. This year it recognizes Dr. Lappalainen’s ongoing research in functional genetic variation in human populations, and her work in elucidating the cellular mechanisms linked to genetic risk for various diseases and traits. Dr. Lappalainen and her lab combine computational analysis of high-throughput sequencing data, human population genetics approaches and experimental work. 

Her group at NYGC and Columbia is highly collaborative and has made important contributions to several international research consortia in human genomics, including the Genotype Tissue Expression (GTEx) Project and the TOPMed Consortium. 

Dr. Lappalainen joined the faculty at Columbia University in 2014 as part of the Department of Systems Biology and NYGC. In 2018, she received the annual Leena Peltonen Prize for Excellence in Human Genetics, which was presented to her in Milan, Italy, at the 52nd European Society of Human Genetics meeting. 

Brian Ji_2
Systems Biology Graduate Brian Ji, PhD

For Brian Ji, the big draw to systems biology stemmed from his passion for applying quantitative approaches to understanding biology. While an undergraduate at the University of Wisconsin-Madison, Ji studied nuclear engineering and credits that training for the way in which he tackles scientific questions: creatively, and as a problem solver. 

“There is no one right approach to asking a question and setting out to answer it, and that freedom is what makes science fun for me,” he says. 

Ji studied under Dr. Dennis Vitkup in the Vitkup lab and completed his thesis defense for systems biology in the fall of 2018.  Also an MD student in Columbia’s Vagelos College of Physicians and Surgeons , Ji was attracted to Columbia because of the close interplay between the Systems Biology Department and the Columbia University Irving Medical Center. “Ultimately,” he says, “the opportunity to sit at the intersection between math, biology and medicine was too good to pass up.”

Ji’s PhD work focused on understanding spatiotemporal dynamics of human gut microbiota. He developed several frameworks that leveraged the increasing availability of high-throughput sequencing data to better understand and precisely quantify patterns of human gut microbiota variability across time and space. His work showed that characterizing dynamics—changes in bacterial abundances in our gut—are critical to understanding how these ecosystems function and is highly connected to multiple factors such as host diet, travel and diet. 

Ji also spent part of his PhD studying limitations of cancer cell growth in different environmental conditions. He credits Columbia for exposing him to a variety of research topics. 

Phyllis Thangaraj
Phyllis Thangaraj, MD/PhD student (Tatonetti lab)

Aspiring physician-scientists from Columbia's Vagelos College of Physicians and Surgeons presented their research posters at the 14th annual MD-PhD Student Research Symposium on April 25. Their research delved into a range of topics, including Alzheimer’s disease, stroke, and stem cells. The event included a guest lecture by an alumna about her own career path as a physician-scientist, and culminated in the poster session judged by MD-PhD alumni who currently work at the University. Department of Systems Biology’s Phyllis Thangaraj, an MD/PhD student in the Nicholas Tatonetti lab , was named one of five poster winners at the event. 

She presented work on applying machine learning methods to phenotype acute ischemic stroke patients in the electronic health records. In cohort research studies, it is essential to identify a large number of subjects in an accurate and efficient manner, but often this requires time-consuming manual review of patient charts. 

“We applied machine learning methods to data within a patient’s electronic health records to develop a high-throughput way to define research cohorts,” explains Thangaraj. “Our test case is in acute ischemic stroke. We extracted clues within a person’s medical record that required minimal data processing to classify those who have had a stroke. In a separate cohort, the UK Biobank, we were able to use our model to identify patients with self-reported stroke but no mention in their medical data with 65-fold better precision than random selection of patients.” Although stroke was the test case in this particular work, she explained that their workflow could be applied to identify patients for cohorts of other diseases, particularly when the dataset has missing data. 

 

Andrea Califano
Andrea Califano, Dr

The migration away from “one-size-fits-all” medicine, particularly in the areas of cancer detection and treatment, holds great promise for patients and the field of precision medicine. Demand and jobs are increasing for researchers, clinicians and professionals who are at home collecting, analyzing and using more and newer forms of data, according to a recent feature reported in Science magazine which spotlights Dr. Andrea Califano , founding chair of the Department of Systems Biology

In the field of oncology, innovations continue to grow rapidly in precision, or targeted medicine, as clinicians seek to find better treatments for specific kinds of cancer, rather than take a blanket approach via the traditional trifecta of radiation, chemotherapy, and surgery. To do so, they must test patients, note mutations, and identify biomarkers to determine what treatments could work best with the fewest side effects.

Scientific breakthroughs, in these areas and more, have led to greater understanding of genes and their functions and have created new opportunities for precision medicine—and for those with technical, research, and clinical skills eager to work in this ever-expanding field. Special consideration will be given to those job applicants who can perform big data analysis and multidisciplinary research. However, new jobs will also emerge in previously unseen areas, such as business, translational medicine, and genetic counseling.

New and powerful tools have aided the precision medicine movement. The Human Genome Project, the first complete mapping of human genes, published its preliminary results in 2001. The project’s numerous benefits include knowing the location of the approximately 20,500 genes identified in the body and gaining a clearer understanding of how genes areorganized and operate.

The Korem Lab

One of the structural variations detected in Anaerostipes hadrus, which is deleted in ~40% of the population (top), and associated with higher disease risk. Genes in this region (bottom) code a composite inositol catabolism - butyrate production pathway, potentially supplying the microbe with additional energy while supplying the host with butyrate, previously shown to have positive metabolic and anti-inflammatory effects. (Credit: Korem lab)

Our gut microbiome has been linked to everything from obesity and diabetes to heart disease and even neurological disorders and cancer. In recent years, researchers have been sorting through the multiple bacterial species that populate the microbiome, asking which of them can be implicated in specific disorders. But a paper recently published in Nature addressed a new question: "What if the same microbe is different in different people?" The study was co-led by Dr. Tal Korem , assistant professor of systems biology and core faculty member in the Program for Mathematical Genomics at Columbia University Irving Medical Center

It has been long known that the genomes of microbes are not fixed from birth, as ours are. They are able to lose some of their genes, exchange genes with other microorganisms, or gain new ones from their environment. Thus, a detailed comparison of the genomes of seemingly identical bacteria will reveal sequences of DNA that occur in one genome and not others, or possibly sequences that appear just once in one and several times over in others. These differences are called structural variants. Structural variants - even tiny ones - can translate into huge differences in the ways that microbes interact with their human hosts. A variant might be the difference between a benign presence and a pathogenic one, or it could give bacteria resistance to antibiotics.

Dr. Raul Rabadan is leading a global research project as part of a new grant from the Pancreatic Cancer Collective to identify high-risk factors of pancreatic cancer. (Courtesy of Stand Up to Cancer)

A global team of researchers led by theoretical physicist Raul Rabadan, PhD, professor of systems biology at Columbia’s Vagelos School of Physicians and Surgeons, and Núria Malats, MD, PhD, head of the Genetic and Molecular Epidemiology Group of the Spanish National Cancer Research Centre (CNIO), are working to develop a comprehensive computational framework that will identify high-risk factors for pancreatic cancer.  

Armed with a new two-year, $1 million grant from the Pancreatic Cancer Collective, the team intends to attack pancreatic cancer research from multiple disciplines—genomics, mathematics and medicine—to provide an integrated, computational approach to studying genomic, environmental and immune factors that could identify populations at high risk of pancreatic cancer. The need for deeper understanding of the contributing factors to this lethal disease is pressing, as pancreatic cancer is projected to become the second leading cause of cancer-related mortality within the next decade. 

Rabadan-led Team for Pancreatic Cancer Collective
Drs. Raul Rabadan and Nuria Malats

Cory Abate-Shen, PhD, a distinguished scientist whose multidisciplinary research has advanced our understanding of the molecular basis of cancer initiation and progression, has been named chair of the Department of Pharmacology at Columbia University Vagelos College of Physicians and Surgeons. Her appointment will be effective April 1, 2019.

Recruited to Columbia in 2007, Dr. Abate-Shen is currently the Michael and Stella Chernow Professor of Urologic Sciences and professor of pathology & cell biology, medicine, and systems biology. She has served as the leader of the prostate program, associate director, and twice as interim director of the Herbert Irving Comprehensive Cancer Center (HICCC) at Columbia University Irving Medical Center and NewYork-Presbyterian.

An internationally recognized leader in genitourinary malignancies, Dr. Abate-Shen is particularly interested in advancing our understanding of the mechanisms and modeling of prostate and bladder tumors. An innovator in the generation of novel mouse models for these cancers, her work has led to the discovery of new biomarkers for early detection, as well as key advances in cancer prevention and treatment.

In the fall of 2018, Dr. Abate-Shen was elected a fellow of the American Association for the Advancement of Science (AAAS). She is an American Cancer Society Professor, the first faculty member at Columbia University Vagelos College of Physicians and Surgeons to have received this honor. Previously, she served as a member of the National Cancer Institute’s Board of Scientific Counselors, and she currently is a member of the board of directors of the American Association of Cancer Research. 

Dr. Abate-Shen will succeed Robert S. Kass, PhD, the Hosack Professor of Pharmacology, Alumni Professor of Pharmacology, and chair of pharmacology since 1995.

Visit the CUIMC Newsroom for the full announcement

Columbia researchers have learned why some glioblastomas—the most common type of brain cancer—respond to immunotherapy. The findings, reported by the CUIMC Newsroom, could help identify patients who are most likely to benefit from treatment with immunotherapy drugs and lead to the development of more broadly effective treatments.

The study, led by Raul Rabadan, PhD, professor of systems biology and biomedical informatics at Columbia University Vagelos College of Physicians and Surgeons and the Herbert Irving Comprehensive Cancer Center, was published online in the journal Nature Medicine

Fewer than 1 in 10 patients with glioblastoma­ respond to immunotherapy, which has shown remarkable success in the past few years in treating a variety of aggressive cancers. But there has been no way to know in advance which glioblastoma patients will respond. Like many other cancers, glioblastomas are able to prevent the immune system from attacking cancer cells. Cancers sometimes put the brakes on the immune system by acting on a protein called PD-1. Immunotherapy drugs called PD-1 inhibitors are designed to release those brakes, unleashing the immune system. Given the success of PD-1 inhibitors in other cancers, doctors were hopeful that the immunotherapy drugs would help patients with glioblastoma. 

To understand why only a few of these tumors respond to the immunotherapy drugs, Dr. Rabadan’s team took a comprehensive look at the tumor microenvironment—which includes the tumor itself and all of the cells that support it—in 66 glioblastoma patients before and after treatment with PD-1 inhibitors (nivolumab or pembrolizumab). Of these, 17 had a response to the drugs of six months or longer.

Nonresponsive tumors had more mutations in a gene called PTEN, which led to higher levels of macrophages, immune cells that usually help the body fight bacteria and other invaders. But in glioblastoma, the macrophages release a number of growth factors that promote the survival and spread of cancer cells.

 

PCF Challenge Award PIs
Principal investigators on the PCF Challenge Award grant, from left to right: Andrea Califano, Michael Shen and Charles Drake.

Columbia University Irving Medical Center experts in prostate cancer will lead a new team research project that tests a novel approach for personalized cancer treatment. 

The two-year project, funded by a $1 million Challenge Award from the Prostate Cancer Foundation (PCF) , combines cutting-edge techniques that include computational methods for targeted drug therapy, single-cell RNA sequencing and novel cancer immunotherapy. The combined approaches are behind a proof-of-concept clinical trial for patients with lethal metastatic prostate cancer.  

PCF Challenge Awards fund projects that bring together experts from a number of related fields to form a team focused on the creation of innovative, effective therapies for advanced prostate cancer. As part of Columbia’s grant, the new clinical trial will take place at the James J. Peters VA Medical Center (also known as the Bronx VA), a partner of Columbia University Irving Medical Center (CUIMC) and New York-Presbyterian .

PCF is recognized as the leading philanthropic organization for prostate cancer research. For the team at Columbia’s Herbert Irving Comprehensive Cancer Center (HICCC ), receiving a Challenge Award from the foundation was more than just an exciting achievement. It underscores CUIMC’s continued commitment to strengthen and expand its expertise in prostate cancer research and care through investments in faculty recruitment, enhanced emphases on bolstering basic science research and clinical trials centered on the disease and direct engagement with PCF. 

Wang Lab
Ravi Sheth (left) and Harris Wang, PhD

Dr. Harris Wang , PhD, and systems biology graduate student, Ravi Sheth , have been awarded a new grant from the Bill and Melinda Gates Foundation to help advance a global health project aimed at reducing childhood mortality in sub-Saharan Africa. The project incorporates Dr. Wang’s innovative microbiome research techniques and applies them to study the antibiotic, Azithromycin, towards understanding its role as an intervention for improving childhood survival rates in rural low-income, low-resource settings.

The study supported by the Gates grant expands on breakthrough research conducted in the MORDOR study , a cluster-randomized trial in which communities in Malawi, Niger and Tanzania were assigned to four twice-yearly mass distributions of either oral Azithromycin or placebo. Children, as young as 12 months of age, participated, and results indicated that the all-cause mortality rate was significantly lower for communities receiving the antibiotic versus placebo. 

“This is an extremely exciting and, in many ways, very surprising result for such an underserved population,” says Sheth, who is a fourth-year PhD student in the systems biology track at Columbia University Irving Medical Center (CUIMC) . “Now it is crucial to understand how Azithromycin is acting to increase survival in such a profound way – to aid scale-up of the intervention and to help optimize the treatment regime and minimize any unintended consequences.” 

The researchers will focus on developing a mechanistic understanding of how Azithromycin reshapes the gut microbiome, and how this altered microbiome state affects the host. The effect of the antibiotic will be studied over space and time to understand the perturbation to the gut ecosystem and resulting community re-configuration and re-assembly, and this information will be utilized to predict and test optimal dosing strategies. 

Peter Sims, PhD
Peter Sims, PhD

The Mark Foundation for Cancer Research has awarded Peter Sims , PhD, an Emerging Leader Award and will support his work to advance a novel use of single-cell RNA sequencing to develop brain cancer treatments. Dr. Sims, assistant professor of systems biology at Columbia University Irving Medical Center, is one of just eight recipients of the inaugural grant, given to promising early career scientists for projects aimed at substantially unmet needs in cancer risk prediction, prevention, detection and treatment. 

Dr. Sims is an early contributor to the emerging field of large-scale single-cell RNA sequencing, which has made it possible to analyze tens of thousands of cells while simultaneously obtaining imaging and genomic data from each individual cell. He will be using this approach to improve patient-derived models of glioblastoma multiforme (GBM), an aggressive form of cancer that invades the brain, making complete resection difficult. In other words, making it extremely difficult in surgery to remove all cancerous cells from the brain. To date, drug therapies for this type of aggressive brain cancer have had limited success, partly because of the heterogeneity of these tumors. Furthermore,  current patient-derived models for researching glioblastoma do not fully recapitulate the cellular diversity of tumor cells that are present in the tumor, so it is extremely challenging to classify those cells in order to match them with the drug therapies that work. 

Indeed, there is a critical need to better characterize and understand GBM. Dr. Sims has collaborated with several brain tumor experts in the Herbert Irving Comprehensive Cancer Center , including Drs. Peter Canoll, Jeffrey Bruce, Antonio Iavarone and Anna Lasorella to advance single-cell genomic approaches to characterizing this disease. Approaching this problem at the single cell level could result in development of novel treatments that  prioritize and identify the specific drug therapies that may actually work on diminishing these tumor cells. The ultimate goal is to attain better predictions of therapeutic efficacy.