Causes

Causes
Just like other cancers, the specific causes of prostate cancer remain unknown. A man's risk of developing prostate cancer is related to his age, genetics, race, diet, lifestyle, medications, and other factors.
Age
The primary risk factor is age. Prostate cancer is very uncommon in men younger than 45, but becomes more common with advancing age. The average age at the time of diagnosis is 70. However, many men never know they have prostate cancer. In the United States in 2005, there were an estimated 230,000 new cases of prostate cancer and 30,000 deaths due to prostate cancer. Men with high blood pressure are more likely to develop prostate cancer.
Genetics
Genetic background may contribute to prostate cancer risk, as suggested by associations with race, family, and specific gene variants. In the United States, prostate cancer more commonly affects black men than white or Hispanic men, and is also more deadly in black men. No single gene is responsible for prostate cancer; many different genes have been implicated. Mutations in BRCA1 and BRCA2, important risk factors for ovarian cancer and breast cancer in women, have also been implicated in prostate cancer. Other linked genes include the "prostate cancer gene", HPC1, the androgen receptor, and the vitamin D receptor.
Diet
Evidence from epidemiological studies supports a possible protective role in reducing prostate cancer for dietary Vitamin B6, selenium, vitamin E, lycopene, and soy foods. Lower blood levels of vitamin D may increase the risk of developing prostate cancer. This may be linked to lower exposure to ultraviolet (UV) light, since UV light exposure can increase vitamin D in the body. Studies comparing men who live in areas of the country with high levels of selenium to men in areas with low levels suggest that this mineral protects against prostate cancer. An analysis in 2002 of the Nutritional Prevention of Cancer Trial revealed that the men who took selenium supplements daily were half as likely to be diagnosed with prostate cancer. However, in 2008, the Selenium and Vitamin E Cancer Prevention Trial (SELECT) indicated that neither selenium nor vitamin E, alone or in combination, was effective for the primary prevention of prostate cancer. Green tea may be protective (due to its polyphenol content), although the most comprehensive clinical study indicates that it has no protective effect.
Research published in the Journal of the National Cancer Institute suggests that taking multivitamins more than seven times a week can increase the risks of contracting the disease. This research was unable to highlight the exact vitamins responsible for this increase (almost double), although they suggest that vitamin A, vitamin E and beta-carotene may lie at its heart. It is advised that those taking multivitamins never exceed the stated daily dose on the label.
Medication exposure
There are also some links between prostate cancer and medications, medical procedures, and medical conditions. Daily use of anti-inflammatory medicines such as aspirin, ibuprofen, or naproxen may decrease prostate cancer risk. Use of the cholesterol-lowering drugs known as the statins may also decrease prostate cancer risk. Infection or inflammation of the prostate (prostatitis) may increase the chance for prostate cancer. In particular, infection with the sexually transmitted infections chlamydia, gonorrhea, or syphilis seems to increase risk. Finally, obesity and elevated blood levels of testosterone may increase the risk for prostate cancer.
Potential viral cause
In 2006, researchers associated a previously unknown retrovirus, Xenotropic MuLV-related virus or XMRV, with human prostate tumors. Subsequent reports on the virus have been contradictory. A group of US researchers found XMRV protein expression in human prostate tumors, while German scientists failed to find XMRV-specific antibodies or XMRV-specific nucleic acid sequences in prostate cancer samples
to be continued....