Taxol synergizes with antioxidants in inhibiting hormal refractory prostate cancer cell growth.

Taxanes are chemotherapeutic agents commonly used to treat various carcinomas. Dietary antioxidants, such as vitamin E, green tea extracts, and isoflavones have been used against prostate cancer, and exhibit anticancer effects both in vitro and in vivo. We evaluated the combined effect of taxol (paclitaxel) with pyrrolidine dithiocarbamate, vitamin E, epigallocatechin gallate, and genistein in killing hormone-refractory prostate cancer cells. Those agents were tested on the hormone-refractory prostate cancer cell line PC-3, and the viability of the cells was determined using MTT {3 (4, 5-dimethylthiazo-2-yl)-2, 5-diphenyl tetrazolium} assay after drug treatment. PC-3 cells were sensitive to these drugs with 50% inhibitory concentrations of 0.1, 23, 220, 1122, and 260 muM, for taxol, pyrrolidine dithiocarbamate, epigallocatechin gallate, genistein, and vitamin E, respectively. Genistein, pyrrolidine dithiocarbamate, and epigallocatechin gallate showed synergistic cytotoxicity to PC-3 cells when combined with 0.01 muM taxol. Only high concentration of vitamin E showed a synergistic effect with this dose of taxol. Further study revealed that 3 combinations could induce sub-G1 phase of cell cycle, induce apoptosis, and increase caspase activity and decrease Bcl-2 expression simultaneously. In conclusion, in addition to vitamin E, incorporation of these antioxidants with taxan-based cytotoxic therapies offers encouraging strategies for combating hormone-refractory prostate cancers.

Graduate Institute of Life Science, National Defense Medical Center, Taipei, Taiwan, Republic of China.

Ping SY, Hour TC, Lin SR, Yu DS.

Anti Oxidants, What They Are

We’re positive you’ve heard of antioxidants. It’s the new buzz word these days and dozens of new products are being made, promoting all the benefits of anti-oxidants from foods to beverages and even skin care too! Why are antioxidants so important to us?

To make it simple, anti-oxidants fight free radicals or rather repair the damage free radicals have on our body. Free radicals which exist in the environment (there is nothing we can do about that) are what cause oxidative damage to our cells. Free radicals are cause everything from pre-mature aging to many diseases. What happens is called oxidation of the body’s cells, and when you include a diet rich in anti-oxidants, they repair some of this damage.

Numerous studies have been performed on the benefits of a diet high in antioxidants. Although quite a few studies state more research is needed (and occuring), with all the potential benefits, why not include antioxidants into your diet?