Chemoprevention of Bladder Cancer: A Mini Review: Beyond the Abstract
To accomplish this goal, we performed a literature search on the PubMed database utilizing key terms such as "chemoprevention", "urinary bladder", "meta-analysis" and "cancer". All relevant abstracts were read and the list of chemopreventive agents was restricted to those discussed in at least two separate and independent studies. The selected articles were then reviewed in full and a final decision was made for their inclusion based on the quantity and quality of data.
Chemopreventive agents that were considered after conducting our literature search, included vitamins A,D & E, selenium, difluoromethylornithine (DFMO), food stuffs (Green Tea, Soy, Garlic, Kava, fruits and vegetables) and cannabis. A careful review revealed that moderate to significant reductions in the bladder cancer risk was observed in vivo with rats treated for vitamin A3, vitamin D4, or Kava5, and in vitro for bladder cancer cell lines treated with vitamin D4, vitamin E6, DMFO7, or flavokawains8 derived from Kava. However, despite the promising nature of the work being done in the lab, clinical studies and meta-analyses exploring the effectiveness of potential chemopreventive agents are still limited in number and often provide little or even conflicting evidence. Separate and independent clinical studies and meta-analyses exploring the effectiveness of vitamin A9,10, vitamin D11,12, and DFMO13,14 vary in their conclusions on whether these agents serve a significant role in reducing bladder cancer risk. It seems that that the search for chemopreventive agents for urinary bladder cancer remains an ongoing endeavor which requires more consistent clinical evidence. Fortunately, the quantity of research being done is rapidly accelerating as scientists and physicians recognize the massive potential that chemoprevention may have in improving patient outcomes and reducing treatment costs15.
Written bye: Cyrus Khoyilar and Ramy Youssef
University of California, Irvine
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