Christopher Ong
A Faculty of Medicine scientist has developed a new protein-based medication that prevents proliferation of prostate cancer, and potentially other cancers.
Christopher Ong, an Associate Professor in the Department of Urologic Sciences and senior research scientist at the Vancouver Prostate Centre, and his colleagues discovered that a gene called SEMA3C is an important driver of cancer cell growth. The gene is pivotal in the development of an embryo, instructing the formation of the embryonic heart and neural development. After an embryo is fully formed, SEMA3C normally goes dormant inside the body.
But SEMA3C sometimes gets reactivated, producing a protein that is released by the cell. That protein binds to other cells and unlocks their machinery for unrestricted multiplication.
“SEMA3C is the key that turns on multiple cancer programs in a cell, inappropriately telling cells that they have to grow a whole new organ—for example, a whole new prostate or breast,” says Dr. Ong, who published his team’s findings Jan. 18 in EMBO Molecular Medicine.
To stop the gene’s function, Dr. Ong’s team created a protein, fused with an antibody, that “jams the lock” on a cell’s surface, preventing the SEMA3C protein key from being inserted.
“In our tumour models, we have shown that our new drug, PB1SD:FC, significantly delays development of treatment-resistant forms of prostate cancer,” he said. “We are optimistic that this new medication may have an enormous impact for future care.”
Prostate cancer is the most common cancer and third leading cause of death among Canadian men, according to the Canadian Cancer Society. While early diagnosis can increase the odds of a positive outcome, the common treatments of androgen receptor inhibitors, radiation and chemotherapy come with their own set of challenges, including urinary, bowel and erectile dysfunction.
“By blocking SEMA3C, multiple pathways that can lead to cancer are also blocked, which could have implications for the treatment of other cancers, such as breast, bladder, colorectal and lung,” says co-author Martin Gleave, Head of the Department of Urologic Sciences and Director of the Vancouver Prostate Centre.
The Vancouver Prostate Centre is working with a company to produce large enough quantities of the drug to enable human clinical trials of PB1SD:FC.