The Ellisen Lab
Dr. Leif Ellisen is Breast Cancer Program Director and a senior Investigator at the Massachusetts General Hospital (MGH) Cancer Center, and Professor of Medicine at Harvard Medical School. He is also co-Leader of the Breast Cancer Program at the Dana-Farber Harvard Cancer Center. He received his undergraduate degree from Harvard University, MD and PhD degrees from Stanford University, and completed residency training, oncology fellowship training, and postdoctoral research training at Brigham and Women’s Hospital, the Dana-Farber Cancer Institute, and MGH, respectively. The Ellisen laboratory’s research is focused on pathogenesis of breast and other cancers, with a particular focus on triple-negative breast cancer (TNBC), incorporating studies of tissue-specific development, transcription factor networks and DNA repair. Through a detailed molecular understanding of these factors we seek to improve diagnosis, therapeutic prediction, and treatment efficacy. Our published work within the last five years has revealed fundamental new genetic mechanisms in HR+ breast cancer (Reinbay et al, Nature 2017; Matissek et al, Cancer Discovery 2018) and discovered a new and therapeutically relevant signature of homologous recombination deficiency (Polak et al, Nat Genet 2017). Our work on a DNA damage response pathway led directly to a national clinical trial for triple-negative breast cancer (TNBC) at 10 major cancer centers (Isakoff et al, J Clin Oncol 2015), and to the discovery of a new oncogene controlling the tumor epigenome (Saladi et al, Cancer Cell 2017). We were among the first to define the intra-tumoral heterogeneity of TNBC (Karaayvaz et al, Nature Comm, 2018), and recently discovered that DNA damage and altered signaling precede histologic abnormalities in noncancerous breast tissues of BRCA2 mutation carriers (Karaayvaz et al, Science Advances, 2020).
The Ellisen lab is uniquely positioned to work at the interface of basic tumor biology and therapeutic application. The lab’s work is strongly supported by a network of collaborators and by the extensive research and clinical infrastructure of the MGH Cancer Center and Harvard Medical School.
I am originally from St. Louis, Missouri and received my undergraduate degree in Chemistry from Washington University in St. Louis. I completed my MD and PhD in Pharmacology and Cancer Biology at Duke University. I came to Massachusetts General Hospital for my residency in Clinical Pathology and fellowship in Molecular Genetic Pathology. My current research involves characterizing early changes in precancerous breast tissue from patients with defects in homologous repair pathways (e.g., BRCA1 mutations) with the goal of developing biomarkers that predict progression to cancer and identifying targets for cancer prevention in this population.
Siang Boon Koh
I am originally from Vancouver, Canada and received my undergraduate in Chemical & Biomedical Engineering from McGill University. I completed both an MSc in Cancer Biology and a PhD in Cancer Drug Discovery at Oxford, focusing on identifying small molecules that can reverse tumour hypoxia. My current major research interests include the characterization of next-generation antibody-drug conjugates for precision oncology and exploiting artificial intelligence for drug discovery.
I am originally from San Juan, Puerto Rico. I received my bachelor’s degree in Pre-Med and Biology from the University of Puerto Rico- Mayaguez Campus. My major research interests involve the identification of transcriptional factors and regulation of immune evasion by chromatin remodeling in Head and Neck Squamous Cell Carcinoma (HNSCC). My future plans include applying for an MD/PhD where I can work and develop my skill set to innovate, bring solutions to diseases affecting our human population but more importantly, to find more efficient ways to improve the quality of life for patients all over the world and science itself.
I am originally from Haiti. I received my Bachelor of Science degrees from Brandeis University in Neuroscience, Biology, and French & Francophone Studies with a minor in Chemistry. I am currently interested in investigating genetic patterns involved in intratumoral heterogeneity and treatment resistance in different types of breast cancers. I have been accepted into the University of Illinois College of Medicine in Chicago, and hope to become a physician-scientist in the future.