Role of Zinc in the Pathogenesis of Prostate Cancer

摘要

Incidence rates of prostate cancer are higher in blacks than in any other racial group. Our laboratory is attempting to decipher the environmental and molecular mechanisms involved in the development of prostate cancer in blacks. It is hypothesized that Africans may have genetically down- regulated their zinc absorption capacity; otherwise, they would absorb abnormally high levels of zinc, resulting in various serious neurodegenerative disorders. We hypothesized that people of African origin may have a lower capacity to transport zinc when compared with other racial groups because of their inherent down-regulation of zinc transporters. This notion was tested by evaluating 58 prostate cancer tissues in 2 major racial groups (30 from whites and 28 from blacks) for their ability to express 2 major human zinc transporters, hZIP1 and hZIP2. In all 30 prostate cancer specimens obtained from white people, the degree of expression of these 2 zinc receptors was high when compared with age-matched specimens obtained from blacks. These data have been confirmed in much larger groups by utilizing zinc indicators that measure the relative intracellular zinc levels in various histological cell types of prostate tissues.