More news from the AACR Annual Meeting

Cruciferous vegetables, we all know them and some of us love them. What we know is that they need to form a part of the standard prostate cancer diet, but some early research shows that a substance found in the them can make prostate cancer cells even more sensitive to taxane therapy with docetaxel (Taxotere), the one approved treatment for castrate resistant prostate cancer.

Assistant professor of pharmacology and clinical biology at the University of Pittsburgh Cancer Institute, Dong Xiao, PhD, claims that phenethyl isothiocyanate, a constituent of edible cruciferous vegetables such as watercress, broccoli, bok choy, and cauliflower, suppresses the growth of cancer cells both in culture and in experimental animals.

Xiao and colleagues demonstrated that combining phenethyl isothiocyanate with docetaxel increased apoptosis (the process of programmed cell death) in androgen-independent human prostate cancer cell lines PC-3 and DU145.

According to Xiao, “The combination treatment with phenethyl isothiocyanate and docetaxel inhibits the tumor growth in PC-3 xenografts, but the combination does not produce any apparent adverse effects on laboratory mice.”

Using Terminal deoxynucleotidyl transferase dUTP Nick End Labeling (TUNEL), researchers observed more than a doubling of apoptotic bodies when the combination treatment was administered to the cells. About 40 apoptotic bodies per high-powered field were observed for each substance by itself. When the substances were combined, Xiao illustrated that about 100 apoptotic bodies per high-powered field could be observed (P<0.05).He also pointed out that in animals, the phenethyl isothiocyanate-docetaxel combination was markedly more efficacious against PC-3 xenografts than either compound by itself.For example, the average tumor volume on the last day of measurement in mice treated with the combination was about 300 mm3 lower than mice receiving phenethyl isothiocyanate alone with a 400 mm3 tumor volume (P=NS); was significantly lower than mice that were administered docetaxel monotherapy that had about a 450 mm3 tumor volume (P=0.0018); and was significantly lower than untreated mice that developed tumor volume in excess of 800 mm3 (P=0.0025).Even without better evidence and a confirming clinical trial why wouldn't you make sure you add cruciferous vegetables to your diet, especially while undergoing chemotherapy?
Source reference:
Singh S, et al “Phenethyl isothiocyanate sensitizes androgen-independent human prostate cancer cells to Docetaxel-induced apoptosis in vitro and in vivo” AACR 2010; Abstract 5395.

The research was supported by a grant from the National Cancer Institute

Joel T Nowak, MA, MSW