Researchers of the Rockefeller University (United States) have shown that treating cancer cells in the prostate with a drug that targets a protein called PHLPP2 can prevent cancer cells from spreading to other organs in the body.
The study, published this Wednesday in the magazine 'Journal of Cell Biology', reveals that the inhibition of PHLPP2 reduced levels of MYC, an oncogenic protein that causes many different types of cancer that can not be treated with conventional therapies. MYC is a powerful oncogene because it promotes cell growth and proliferation and improves cell metabolism and survival. One type of cancer associated with high levels of MYC is metastatic prostate cancer.
The PHLPP2 protein is also elevated in metastatic prostate cancer cells. PHLPP2 is an enzyme phosphatase that can remove phosphate groups from other proteins, but the function of this protein in prostate cancer was not clear before. In the new study, researchers found that metastatic prostate cancer cells require PHLPP2 to survive and proliferate. They discovered that PHLPP2 helps stabilize MYC by removing a phosphate group that would otherwise trigger the destruction of MYC.
The researchers removed the PHLPP2 gene in experimental models and found that doing so prevented prostate cancer cells from metastasizing to other organs. This is significant because researchers have not been able to develop treatments that directly inhibit MYC, as it does not contain any characteristics that can be easily treated with a medication.
Next, the scientists went to human prostate cancer cells, which treated them with a drug that inhibits PHLPP2. This reduced MYC levels and caused the cells to stop proliferating and die. PHLPP2 does not seem to play any essential role in healthy cells, so the researchers suggest that the enzyme could be an effective way to indirectly target MYC in metastatic prostate cancer and possibly also in other cancers.