Ramon Parsons, M.D. Ph.D.
Fax - 212 851-5256
Physician Summary
Ramon Parsons' primary interest is to understand the mechanism of action of the PTEN tumor suppressor. Inactivation of PTEN is associated with activation of the PI3K pathway. The research program in the laboratory seeks to understand the regulation of PTEN and other members of the PI3K pathway such as IRS2, PIK3CA, PDPK1, and FOXO1/FOXO3/FOXO4. Recent accomplishments have included identifying that PTEN inactivation is associated with an impaired DNA damage response, increased DNA damage, and reduced CHK1 function due to its sequestration in the cytoplasm (Puc et al Cancer Cell 2005; Puc et al. Cell Cycle 2005). His laboratory has identified that PIK3CA mutation occurs frequently (~25%) in breast cancer and is associated with estrogen receptor and PTEN expression in collaboration with Ake Borg at Lund University(Saal et al. Cancer Research 2005). He has also investigated the role of PDPK1 in PTEN+/- tumor formation in collaboration with Dario Alessi of University of Dundee and shown that reduced PDPK1 substantially reduces PTEN-dependent tumor formation (Bayascas et al., Current Biology 2005).
In 2007, the group has established that a gene expression signature for PTEN/PI3K pathway activation is predictive of metastasis and poor prognosis in solid tumors(Saal et al. PNAS, 2007). In addition, Dr. Parsons is interested in defining genetic alterations that occur in sporadic breast cancer that contribute to the pathogenesis of the disease. As part of this investigation, he identified a novel mutation of SMAD4 that led to a substantial reduction in the half-life of the encoded protein. (Jakob et al. Genes Chromosomes & Cancer 2005).
Clinical Expertise
Research FacultyMolecular Genetics Research
Appointments
Avon Foundation Professor of Pathology & Medicine, Columbia University Medical CenterInstitute for Cancer Genetics & Irving Cancer Center, Columbia University Medical Center
Education
A.B., 1983, Columbia University, New York, NYM.D. & Ph.D., 1992, State University of New York at Stony Brook