Program Faculty

The Frohman laboratory cloned and has been exploring translational roles for the mammalian family of lipid-signaling Phospholipase D genes for the two decades. PLD superfamily members are involved in many physiological and pathophysiological settings including immune defenses, cancer, neurodegenerative disease, diabetes, cardiovascular disease, and fertility. Among other approaches, Dr. Frohman recently been generating and publishing findings with mice lacking each of the PLD isoforms, and have uncovered a number of fascinating stories with human health relevance. Recent work has included exploring the potential of using a Phospholipase D small molecule inhibitor as a therapeutic in stroke, cardiovascular disease and cancer progression settings. Cell biological processes of particular interest include mitochondrial fusion and fission, subcellular trafficking of membrane vesicles during signaling activated exocytosis and endocytosis, viral trafficking through the Golgi complex, integrin activation, and receptor signaling.

Dr. Li’s focus is on prevention, diagnosis, and treatment of digestive diseases. Her current research interests are on defining the role of the gut microbiome in digestive diseases, particularly in inflammatory bowel diseases, colon cancer, and functional GI disorders, such as irritable bowel syndrome. Her specialty, as a scientist, is in translational research; focusing on taking scientific discoveries and translating them into ways to help improve people’s health. Dr. Li participates in the training of medical students, residents, and fellows at the Stony Brook University School of Medicine. She also mentors several undergraduates as well as high school students in conducting independent research projects in her laboratory. Dr. Li is especially interested in improving undergraduate premedical education, particularly for students coming from disadvantaged backgrounds

Dr Ghaleb studies the physiology of the digestive system and pathobiology of digestive diseases. He is seeking to understand the mechanisms that regulate growth, differentiation and development of the gastrointestinal (GI) tract at the molecular and cellular levels. A recent focus is how intestinal stem cells behave under different conditions. He is also investigating the pathophysiological mechanisms underlying common GI diseases including GI cancer and inflammatory bowel disease with the intention of developing novel therapeutic approaches to treat them.

Dr. Meliker’s research contributes to the fields of exposure science, health geography, and environmental epidemiology. His scholarship falls into two lines of inquiry: (1) identifying environmental factors that play important roles in disease morbidity, and (2) developing space-time methods that improve our ability to investigate exposure-disease relationships. Highlights of his work include pioneering development of space-time information systems for lifetime exposure reconstruction, and epidemiology of low-level exposure to arsenic in drinking water. He has published on drinking water contaminants, air pollutants, arsenic, cadmium, asthma, osteoporosis, stroke, and different types of cancers, and enjoys tackling environmental epidemiologic and spatio-temporal methodological problems to advance population health.

Dr. Nemesure is the Director of the Cancer Prevention and Control Program for the Stony Brook Cancer Center and also serves as the Director of the Center’s Lung Cancer Program. She has been a Principal Investigator (PI) on several major research grants for the past 20 years and has established a solid track-record of developing, implementing and directing projects related specifically to cancer over. These studies include two large, longitudinal NCI/NHGRI funded investigations - the Barbados National Cancer Study and the Prostate Cancer in a Black Population Study, which focused on the identification of epidemiologic and genetic risk factors for breast and prostate cancer. Additionally, she has served as a co-PI and Co-Investigator on 3 other population-based NIH-funded investigations and has led several smaller ancillary studies including evaluations of: i) novel approaches to breast cancer screening; and ii) individual-, socio-cultural- and system-level variables influencing prostate cancer healthcare utilization.

Dr. Powers’ main focus has been application of genome-wide DNA copy number profiling to identify recurrent amplified candidate driver genes. This work has involved in vitro and in vivo functional assays to validate the role of candidate driver genes in oncogenesis. Discoveries in this area include gene amplification of PPM1D and ACK1 in breast and prostate adenocarcinomas and more recently, activation of FGF19 by genomic amplification and overexpression in hepatocellular carcinoma. In addition to copy number alterations in cancer, Dr. Powers has applied genome-wide methods to the study of mutational changes, epigenetic changes, and tumor-stromal interactions. Current projects include: (1) Functional genomic Identification of drivers and dependencies in breast cancer (2) Computational analysis of large-scale cancer genomic datasets (3) Studying the clonal dynamics of cancer cells using single-cell barcoding (4) Combinatorial genetic screening using tandem-integration of multiple barcodes and (5) Discovery of biomarkers by genomic analysis of exosomes.

Dr. Rigas has pursued a career as a physician-scientist. Dr. Rigas has spent the last two decades working on the mechanisms of carcinogenesis and cancer control with pharmacological agents. Highlights of his work: Demonstration of the increased PGE2 levels in human colon cancer; First delineation of the cytokinetic effect of NSAIDs and eicosanoids in cancer; First description of the COX-independence of the anticancer effect of NSAIDs, a concept now expanded to many anticancer agents; Proposing and establishing that oxidative stress mediates the anticancer effect of modified NSAIDs; and Discovering that annexin A1 is an endogenous regulator of NF-κB and designing novel annexin-based. In addition, Dr. Rigas has: invented a platform technology for the chemical modification of existing compounds generating new chemical entities with enhanced potency and safety; studied extensively the nitric oxide-donating NSAIDs, including efficacy, PK/PD, metabolism, toxicology studies and conducted an FDA-approved, NIH-funded clinical trial; obtained the first ever infrared spectra from cells and tissues and co-invented infrared microscopy; and co-invented the RecA-based method for screening DNA libraries; a commercially available kit based on this method was used extensively for two decades.

Dr. De Los Santos focus is on chemical toxicology and understanding how endogenous and exogenous compounds react with DNA bases and change the structure and function of the genes. He is determining the solution structures of damaged DNA molecules and relating them to DNA mutagenesis and repair. He is also looking at exogenous gene toxicants, such as Aristolochic acids, acetylamino-fluorene, and nitro-benzanthrones, all of which are strong mutagens and mammalian carcinogens. The hypothesis is that the systematic structural characterization of damaged DNA will permit the mechanistic understanding of chemical genotoxicity, uncover novel protein-DNA interactions and identify useful biomarkers of exposure and disease risk.

: Dr. Shroyer is Board Certified in Anatomic and Clinical Pathology , with subspecialty certification in Cytopathology. He is a general surgical pathologist with a subspecialty expertise in gynecologic oncology. He also has extensive experience in gynecologic and non-gynecologic cytopathology, including fine needle aspiration cytopathology. Dr. Shroyer pioneered novel methods to improve the accuracy of the cytologic and histologic classification of tumors. He authored the first report on the analysis of x-chromosome inactivation in archival tissues as a marker of clonality. Dr. Shroyer contributed to the early validation of tyramide-based signal amplification technology for in situ hybridization and high sensitivity immunohistochemistry and has been engaged in the development of novel approaches for antibody labeling using nanoparticles for both in vivo imaging and for immunohistochemical applications. Ongoing areas of investigation in Dr. Shroyer’s laboratory are focusing on the discovery of the mechanistic basis of nuclear keratin 17 as a prognostic biomarker in carcinomas of the female genital tract, pancreas, and other anatomic sites.

Dr. Sniders laboratory focus on the role and regulation of sphingolipid metabolizing enzymes and their lipid products in the pathobiology of inflammation. Specifically, she is interested in gastrointestinal inflammation and inflammatory bowel disease; potential precursors to colon cancer. She employs both in vitro and in vivo model systems to examine the role of dietary modulation on sphingolipid metabolism and inflammation. She examines the inflammatory signaling pathways, histopathology and global proteome regulated by diet and sphingolipids in order to determine novel potential nutritional and therapeutic targets in gastrointestinal inflammation.

Dr. Thompson is new to Stony Brook University. She leads a nationally prominent research program that has focused on the evolution of molecular and cellular changes that occur during the development of colorectal and breast cancer. Her research is concentrated primarily on the discovery and validation of biomarkers that help identify individuals at greatest risk for cancer recurrence, to enable more precise and effective methods to treat cancer patients. Previously at the University of Arizona as a faculty member in the Department of Pathology and the Arizona Cancer Center, Dr. Thompson was the Program Leader of the Cancer Prevention and Control Program and the PI of the Specialized Program of Research Excellence (SPORE) in Gastrointestinal Cancers. Dr. Thompson has an outstanding track record of achievements in nationally prominent basic and translational cancer research programs.

Discovery of biomarkers by genomic analysis of exosomes. Styliani E. Tsirka, PhD: Dr. Tsirka’s research interests concern the communication, signaling events and cell-cell interactions between neurons and microglia following normal or exaggerated stimulation of the central nervous system that lead to reorganization of neuronal connections in the brain or neuronal cell death. Gliomas are highly aggressive and accompanied by numerous microglia/macrophages (MG/MP) in and about the tumor. Little is known about what MG/MP do in this setting, or whether modulating MG/MP activation might affect glioma progression. Dr. Tsirka’s group, using a glioma-microglia in culture system, are establishing the effects that tumor and microglia have on each other. The group is assessing glioma progression in vivo after MG/MP ablation or in the setting of exaggerated MG/MP activation.

Dr. Williams is the founding Dean for Student Diversity, a position that serves as the primary liaison between Stony Brook Medicine and Stony Brook University, acting to encourage our very best UR undergraduate students to seek out and succeed in careers in the health sciences. She is also an affiliate faculty member in I-STEM education where she works with underrepresented community college students who are interested in biomedical careers. She is the founding Dean for Student Diversity. In the area of research, she recently defined the mechanistic role of NF-κB in colon cancer prevention in response to novel derivatives of NSAIDs (chemopreventive agents). Currently, she is addressing the underlying genetic/regulatory causes associated with cancer racial health disparity. As such, Dr. Williams’ group is assessing the dysregulation of miRNAs (which represent emerging major regulators of gene expression) and aberrant DNA methylation as factors influencing racial health disparity in the incidence and mortality rates of colorectal cancer. She has secured several research grants to support her work, including two current grants from the NIH, as well as playing a pivotal role in a NIH planning grant designed to bring a large collaborative study to Stony Brook University to study gastrointestinal malignancies in underserved populations. identify pathways and novel targets for cancer treatment. He is currently exploring the roles of mitochondrial STAT3 and phospholipase d1 in pancreatic carcinogenesis.

Dr. Yang’s research interests focus on understanding the molecular mechanisms that control proliferation and differentiation of intestinal epithelial cells and how these processes are perturbed in gastrointestinal malignancies. His clinical interest is focused on hereditary colon cancer syndrome and he works closely with national organizations including the Centers for Disease Control and Prevention (CDC) to establish genetic epidemiology of such diseases. Dr. Yang has concentrated on the roles played by a number of Krüppel-like transcription factors (KLFs) that exert crucial roles in the biology and pathobiology of the gut epithelium including stem cells and cancer. He has been a pioneer in the cloning and characterization of kruppel-like factors (KLF) in the gut, and as an outstanding physician-scientist, has investigated these molecules for the understanding of their role in cancer. As an educator, Dr. Yang has routinely taught medical and graduate students, as well as medicine residents and gastrointestinal fellows in GI physiology, cancer biology and genetics. He has mentored numerous GI fellows, two dozen research postdoctoral fellows, and about a dozen each of graduate students and residents. Many of his former mentees are now established academicians in their own rights in institutions.