Vitamin and mineral use and risk of prostate cancer: misleading?

摘要

I read the paper "Vitamin and mineral use and risk of prostate cancer: the case-control surveillance study" by Zhang et al. published in Cancer Causes and Control (2009) 20: 691-698.This paper is misleading. There is no molecular genetic evidence that zinc is mitogenic. Cell culture studies, animal studies, or experience in humans for the past 45 years have not shown that zinc administration causes malignancy. In the case of prostate cancer, many believe that chronic inflammation precedes the cancer [1]. Zinc is an anti-inflammatory agent. Zinc, in the cell induces A-20, an inhibitor of NF-kB, which results in decreased gene expression and production of TNF-a [2, 3]. Based on this, one would expect that zinc may be a preventive agent for prostate cancer.