A member of the UA Skin Cancer Institute, Dr. Shaheen received his medical degree from Damascus University in Syria, and completed his fellowship at Indiana University Medical Center, specializing in hematology/oncology. Dr. Shaheen is certified by the American Board of Internal Medicine in hematology and medical oncology.
Dr. Shaheen is a Physician-Scientist with clinical and laboratory research efforts. He is specialized in the treatment of melanoma, as well as kidney and bladder tumors. His clinical trial portfolio includes a spectrum of novel immuno- and targeted therapies. As an example, his team was part of the trial that led to the FDA approval of a powerful immunotherapy combination ( ipilimumab and nivolumab) for the treatment of metastatic melanoma ( NEJM, 2015 May 21;372(21):2006-17)
His lab investigates mechanisms of DNA damage response and repair in connection to cancer generation and resistance to therapeutic agents, with an emphasis on the role of the ubiquitin pathway in this process.
Homologous Recombination: Is an essential process for the repair of DNA double strand breaks. Dr. Shaheen's lab implicated two ubiqutin proteins (the ubiquitin E3 ligase Pso4, and the deubiquitylase USP20) in this process ( J Biol Chem 2015 May 21;372(21):2006-17, J Biol Chem. 2014 Aug 15;289(33):22739-48). Depletion of these proteins lead to cancer cell sensitivity to radiation and chemotherapy drugs.
His lab also investigates the important tumor suppressor deubiquitylase protein (Brca1 associated protein 1 or BAP1) in carcinogenesis. This protein’s function is absent in a significant percentage of cancers including ocular, familial melanoma, renal, and bladder tumors. Understanding BAP1 enigmatic function will be the first step in designing drugs that can help patients with BAP1 pathway mutations.