To study the effect of insulin on advanced androgen-indpendent prostate cancer (pc-3) cells
Prostate cancer is one of the major causes of mortality in males over the age of fifty all over the world. Many factors including genetics and diet have been associated with the development of prostate cancer. Hyperinsulinemia has been found to be associated with higher risk of Prostate cancer. Diabetes type-2 is accompanied with hyperinsulinemic state. Both cancer and diabetes are metabolic disorders and often diabetes is correlated with cancer. This study reveals that insulin acts as a mitogen hence increases proliferation in PC-3 cells. Reactive oxygen species are by product of cellular metabolism. Insulin treatment increases cellular metabolism due to which ROS level also increases at higher insulin doses. ROS is necessary for many cells signalling process, abnormal increase in ROS level can cause mutational DNA damage and affects protein folding. Antioxidants and free radical balance is critical for normal cellular functioning. Superoxide dismutase is an important antioxidant enzyme, which keeps ROS level low by dismutation of superoxide anion into hydrogen peroxide. This is further metabolised by catalase. In our study we have found that at lower insulin doses SOD level increases but at higher insulin doses SOD expression decreases significantly. This may be the possible reason of ROS increase. Matrix metalloproteinase's expression is modulated by insulin, which can lead to increase in malignancy. All factors stated above indicate that hyperinsulinemia can lead to tumor progression.