—by Cate Stevenson, BA
The prostate is a gland in the male reproductive system. Prostate cancer occurs when cells in the prostate mutate and begin to multiply out of control. The peripheral zone of the prostate usually develops cancer first. These small clumps of cancer cells attach to an otherwise healthy prostate. When and if the cells begin to multiply, they can spread to the surrounding prostate tissue. Eventually a tumor may invade nearby organs, such as the seminal vesicles, bladder or rectum. Or tumor cells may travel into the lymphatic system and the bloodstream. Often those with prostate cancer have no symptoms. Others experience similar symptoms to those found with BPH, including trouble with sexual function.
When looking for a cure for prostate cancer, scientists have focused on “androgen receptors.” Androgens are hormones (such as testosterone) that are important for normal male sexual development before birth and during puberty. Androgen receptors allow the body to respond appropriately to these hormones. Typical prostate cancer treatments involve drugs that slow production of androgen. But, according to researchers, this type of treatment generally becomes less effective over time, as cancer cell resistance strengthens and multiplies.
It’s exciting news then, to read about some cutting-edge research being done at the Michigan Center for Translational Pathology. There, scientists believe they have uncovered the primary cause of prostate cancer — and it has very little to do with androgen receptors. The main cause of prostate cancer could, in fact, be the fusion of two genes. When these two genes fuse, it sets the stage for abnormal prostate cell growth.
The research team likens gene fusion to an on switch for prostate cancer development. The cancer is set in motion with the initial fusion of a prostate gene with a cancer-causing gene. The researchers were able to use high-tech genetic mapping techniques to discover that, once fusion takes place, androgen receptors get blocked, in turn cutting off normal prostate cell growth while allowing cancer to spread.
The research team concludes that their study shows the underlying problem in prostate cancer is the presence of gene fusion, not the androgen receptor. In some contexts, androgen signaling is actually a good thing, but the presence of the gene fusion blocks androgen receptor signaling. This in turn alters normal prostate cell development.
It will be interesting to see if scientists can use this discovery to press forward and find a cure for prostate cancer. Perhaps there will be a way to stop gene fusion from happening, thereby protecting healthy prostate genes from cancer-causing genes. And if this could be figured out for prostate cancer, perhaps it might provide clues about how to prevent other types of cancer as well.