David De Semir, Ph.D., Associate Scientist

California Pacific CURRENTS: The online journal of CPMC Research Institute

Research to improve the diagnosis and treatment of melanoma and other cutaneous malignancies

Research Overview

  • Dr. David De Semir conducts research to discover and validate melanoma progression genes that drive cancerous growth, and he leads studies on the molecular classification of primary cutaneous melanoma.
  • His research helped reveal that melanoma patients with higher expression of PHIP (pleckstrin homology domain-interacting protein) develop metastasis earlier and have poorer prognosis versus those with lower PHIP expression.
  • Based on these findings, Dr. De Semir is examining the wider role of PHIP in the progression of other cancers including breast and lung cancers, and glioblastoma.
  • He is studying the role of the protein NCOA3 (nuclear receptor coactivator 3) in regulating the DNA damage response after UV exposure, in melanoma. Ongoing studies will assess the mechanisms by which NCOA3 activity increases risk for the development and progression of melanoma.
  • Through his research and in collaboration with Dr. Mohammed Kashani-Sabet, the lab has uncovered novel biomarkers associated with distinct stages of melanoma progression.
  • Dr. De Semir leads basic science on ovarian cancer and lung cancer for CPMCRI's Cancer Avatar Project.


Dr. De Semir received a Ph.D. in genetics from Pompeu Fabra University in Barcelona, Spain. He completed post-doctoral fellowships in melanoma biology at the University of California at San Francisco, and California Pacific Medical Center Research Institute (under the mentorship of Dr. Kashani-Sabet).


Publication Search


Dar AA, Majid S, Bezrookove V, Phan B, Ursu S, Nosrati M, De Semir D, Sagebiel RW, Miller JR 3rd, Debs R, Cleaver JE, Kashani-Sabet M, BPTF transduces MITF-driven prosurvival signals in melanoma cells. Proc Natl Acad Sci U S A

Phan B, Majid S, Ursu S, de Semir D, Nosrati M, Bezrookove V, Kashani-Sabet M, Dar AA, Tumor suppressor role of microRNA-1296 in triple-negative breast cancer. Oncotarget

Dar AA, Nosrati M, Bezrookove V, de Semir D, Majid S, Thummala S, Sun V, Tong S, Leong SP, Minor D, Billings PR, Soroceanu L, Debs R, Miller JR 3rd, Sagebiel RW, Kashani-Sabet M, The role of BPTF in melanoma progression and in response to BRAF-targeted therapy. J Natl Cancer Inst

Sun V, Zhou WB, Nosrati M, Majid S, Thummala S, de Semir D, Bezrookove V, de Feraudy S, Chun L, Schadendorf D, Debs R, Kashani-Sabet M, Dar AA, Antitumor activity of miR-1280 in melanoma by regulation of Src. Mol Ther

Bezrookove V, De Semir D, Nosrati M, Tong S, Wu C, Thummala S, Dar AA, Leong SPL, Cleaver JE, Sagebiel RW, Miller JR 3rd, Kashani-Sabet M, Prognostic impact of PHIP copy number in melanoma: linkage to ulceration. J Invest Dermatol

Dar AA, Majid S, Rittsteuer C, de Semir D, Bezrookove V, Tong S, Nosrati M, Sagebiel R, Miller JR 3rd, Kashani-Sabet M, The role of miR-18b in MDM2-p53 pathway signaling and melanoma progression. J Natl Cancer Inst

David De Semir, Ph.D., Associate Scientist
Primary Research Interests
  • Development and validation of molecular prognostic and predictive factors for melanoma and other cancers
  • Identification of functional mediators of tumor progression and metastasis