Researchers discovered that PM-TRPM8 was expressed only by mature, differentiated epithelial luminal cells and was overexpressed in cancer.
Scientists at the Université des Sciences et Technologies de Lille, France, discovered that the protein known as TRPM8 plays a role in prostate cancer. The study found high levels of TRPM8 in prostate carcinoma compared to normal prostate epithelial cells.
In normal prostate epithelium, cells coexist in many stages of development/differentiation. Disrupted or dysregulated differentiation and proliferation are major causes of cancer. In the study, researchers found that only mature, differentiated human prostate primary epithelial luminal cells express functional plasma membrane TRPM8 (PM-TRPM8) and that prostate cancer cells possessed higher PM-TRPM8 levels than normal cells.
They also found that endoplasmic reticulum TRPM8 (ER-TRPM8) retained it’s function as a calcium release channel, independent of the differentiation state of the cell, and may be an important factor in controlling the growth of prostate cancer cells. The authors hypothesize that the constant activity of ER-TRPM8 may be the result of the expression of a truncated form of TRPM8. They suggest that specific inhibition of ER-TRPM8 or PM-TRPM8 may prove to be of use in the treatment of prostate cancer, depending on the stage of the tumor.
The research appears in the June issue of the Journal of Clinical Investigation.