Houston Methodist. Leading Medicine.
Houston Methodist. Leading Medicine

Sankar Mitra, Ph.D.

Sankar Mitra, Ph.D.

Full Member 
Houston Methodist Research Institute
Department of Radiation Oncology
Houston Methodist Hospital

E-mail:  smitra@houstonmethodist.org
Phone: 713-441-7148


M.S.   Calcutta University, Calcutta, India (Biochemistry)
Ph.D.   University of Wisconsin, Madison, WI (Biochemistry)

Postdoctoral Training

Research Fellow, Department of Biochemistry, Calcutta University, India
Research Assistant and University Fellow, Department of Biochemistry, University of Wisconsin, Madison, WI
Postdoctoral Fellow in Biochemistry, Stanford Medical School, CA



After earning a Ph.D. from the University of Wisconsin in 1964, Dr. Mitra did postdoctoral research in Arthur Kornberg’s laboratory at Stanford Medical School. He then returned to India to join Bose Institute, Calcutta, as an assistant professor in 1966, and became an associate professor in 1971. He came back to the U.S. in 1971 to join the Biology Division of Oak Ridge National Laboratory as a senior research investigator and subsequently became leader of the Nucleic Acid Enzymology Group. He also served as an adjunct professor of the University of Tennessee Graduate School of Biomedical Sciences. Dr. Mitra moved to the newly created Sealy Center for Molecular Science at the University of Texas Medical Branch (UTMB), Galveston, TX in 1992 as professor of Biochemistry & Molecular Biology, and later as senior scientist in the Sealy Center for Molecular Medicine. After his retirement from UTMB in 2013, he joined Houston Methodist Research Institute as a full member in Radiation Oncology. He was elected a fellow of AAAS in 1989 and as a fellow of the Japan Society for Promotion of Science, participating in lecture tours in Japan in 1991, 1999, and 2008. He has been continuously funded by NIH since 1982 and has been serving on various NIH review panels.

Dr. Mitra has published more than 200 original research papers, review articles, and book chapters. He gives several invited lectures every year at various national and international conferences of scientific societies on cancer, genome damage, and repair.  

Description of Research

Working in the broad area of genome damage, its repair, and its influence in carcinogenesis and cancer therapy, Dr. Mitra has made several seminal discoveries during his tenure at Oak Ridge National Laboratory, including the characterization of the E. coli repair protein for the mutagenic DNA base O-6 methylguanine produced by mutagens and anticancer alkylating agents, the naming of the repair protein MGMT, and the cloning of human MGMT. More recently, Dr. Mitra’s group characterized a new family of DNA repair proteins that they named NEILs for oxidative genome damage. The recent research focus of Dr. Mitra’s group is enhancement of chemo/radiation sensitivity of tumor cells using targeted DNA repair inhibitors. After the early studies on MGMT inhibition, his current research aims to identify inhibitors for repair pathways for oxidative/radiation damage.

Dr. Mitra’s research is supported by multiple R01 grants from the National Institutes of Health.

Major Areas of Research

genome damage, repair, cancer formation and therapy

Recent Publications

Hegde ML Hegde PM, Bellot LJ, Mandal SM, Hazra TK, Li GM, Boldogh I, Tomkinson AE, Mitra S. Prereplicative repair of oxidized bases in human genome is mediated by NEIL1 DNA glycosylase in association with replication proteins. Proc Natl Acad Sci USA. 2013 110(33):E3090-9. PMID: 23898192

Boldogh I, Hajas G, Aguilera-Aguirre L, Hegde ML, Radak Z, Bacsi A, Sur S, Hazra TK, Mitra S. Activation of ras signaling pathway by 9-oxoguanine DNA glycosylase bound to its excision product, 8-oxoguanine. J Biol Chem. 2012 287(25):20769-73. PMID:2256894

Hegde ML, Hegde PM, Holthauzin LM, Hazra TK, Rao KSJ, Mitra S. Specific inhibition of NEIL-mediated repair of oxidized bases in genome by copper and iron: Potential etiological linkage to neurodegenerative  disorders. J Biol Chem. 2010 285:28812-25. PMID: 20622253

Szczesny B, Tann AW, Longley MJ, Copeland WC, Mitra S. Long patch base excision repair in mammalian mitochondrial genomes. J Biol Chem. 2008 283:26349-56. PMCID: PMC2546560

Bhakat KK, Mokkapati SK, Boldogh I, Hazra TK, Mitra S. Acetylation of human 8-oxoguanine-DNA glycosylase by p300 and its role in 8-oxoguanine repair in vivo. Mol Cell Biol. 2006 26:1654-65.

Izumi T, Brown DB, Naidu CV, Bhakat KK, MacInnes MA, Saito H, Chen DJ, Mitra S. Two essential but distinct functions of the mammalian AP-endonuclease. Proc Natl Acad Sci USA. 2005 102:5739-43.

Wiederhold L, Leppard JB, Kedar P, Karimi-Busheri F, Rasouli-Nia A, Weinfeld M, Tomkinson AE, Izumi T, Prasad R, Wilson SH, Mitra S, Hazra TK. AP endonuclease-independent DNA base excision repair in human cells. Mol Cell. 2004 15:209-20.

Bhakat KK, Izumi T, Yang SH, Hazra TK, Mitra S. Role of acetylated human AP-endonuclease (APE1/Ref-1) in regulation of the parathyroid hormone gene. EMBO J. 2003 22:6299-6309.

Szczesny B, Hazra TK, Papaconstantinou J, Mitra S, Boldogh I. Age-dependent deficiency in import of mitochondrial DNA glycosylases required for repair of oxidatively damaged bases. Proc Natl Acad Sci USA. 2003 100:10670-5. 

Hazra TK, Izumi T, Boldogh I, Imhoff B, Kow YW, Jaruga P, Dizdaroglu M, Mitra S. Identification and characterization of a human DNA glycosylase for repair in modified bases in oxidatively damaged DNA. Proc Natl Acad Sci USA. 2002 99:3523-8.