Herbal Extract May Compromise Prostate Cancer Chemotherapy Drug PC-SPES, a dietary supplement taken by some men as a treatment for prostate cancer, may compromise the effectiveness of chemotherapeutic agents, such as paclitaxel, by interfering with microtubule polymerization, according to a study in the November 6 issue of the Journal of the National Cancer Institute.
Michael J Bonham and Peter S. Nelson, M.D., of the Fred Hutchinson Cancer Research Center in Seattle, and their colleagues found that treatment of prostate cancer cells in vitro with PC-SPES altered the expression of numerous cytoskeleton genes, including á-tubulin, a component of microtubules and a target for the chemotherapeutic agent paclitaxel. The authors also found that PC-SPES reduced paclitaxel activity in vitro and in vivo.
"Our results suggest that PC-SPES and paclitaxel may have conflicting effects if administered together in the clinical setting," the authors conclude. "The combination of PC-SPES and paclitaxel reduced the effectiveness of paclitaxel treatment in both androgen-sensitive and androgen-independent models of prostate carcinoma."
Contact: Kristen Woodward, Fred Hutchinson Cancer Research Center, 206-667-5095; firstname.lastname@example.org
Garlic, Chives, and the Like Associated with a Reduced Risk of Prostate Cancer Consumption of garlic, chives, and other allium vegetables may be associated with a reduced risk of prostate cancer, according to a study in the November 6 issue of the Journal of the National Cancer Institute. Ann W. Hsing, Ph.D., of the National Cancer Institute and her colleagues interviewed 238 men with prostate cancer and 471 men without prostate cancer about their consumption of various foods. The authors found that men who consumed the highest amounts of allium vegetables (more than 10 g/day) had approximately half the risk of prostate cancer of men who consumed the lowest amounts of allium vegetables (less than 2.2 g/day). Garlic and scallions were associated with the lowest risk. The authors note that the association was also more pronounced for men with localized prostate cancer than with advanced prostate cancer.
Clinical Trial Results Are Put into Practice Quickly How quickly research results are disseminated to physicians and other health practitioners can affect how quickly patients receive the benefit. In the November 6 issue of the Journal of the National Cancer Institute, Angela Mariotto, Ph.D., of the National Cancer Institute, and her colleagues modeled trends in the use of adjuvant multi-agent chemotherapy, tamoxifen, and the combination of both treatments for early-stage breast cancer in the United States from 1975 through 1999. The patterns described by the model indicate that the results of clinical trials are disseminated fairly rapidly to physicians and their patients.
"Rapid dissemination likely reflects the importance that physicians and patients attach to the latest results from clinical trials," the authors say. "It also emphasizes that research results are being transmitted in a timely fashion and suggests that the mechanism for wide dissemination, such as medical journals, scientific meetings, NCI clinical announcements, and consensus conferences, are effective in reaching practicing physicians."
Sluggish Gene May Reduce Effectiveness of Tamoxifen Differences in how some women with breast cancer respond to tamoxifen therapy may be explained in part by differences in gene activity, suggests a study in the November 6 issue of the Journal of the National Cancer Institute. Susan Nowell, of the U.S. Food and Drug Administration's National Center for Toxicological Research, and her colleagues examined survival outcomes and activity of a gene called SULT1A1, which is involved in tamoxifen metabolism, among 160 women with breast cancer who received tamoxifen and 177 women with breast cancer who did not receive tamoxifen. Women who received tamoxifen and had two copies of the SULT1A1 low-activity gene had roughly three times the risk of death as those who had at least one copy of the normal gene. Among patients who did not receive tamoxifen, there was no association between survival and the SULT1A1 genotype.
Epstein Barr Virus Predicts Survival of patients with Nasopharyngeal Cancer Nasopharyngeal cancer (NPC) is associated with Epstein-Barr virus (EBV) infection, and the presence of EBV DNA in the blood can predict survival of patients with NPC. In a study in the November 6 issue of the Journal of the National Cancer Institute, Anthony Chan, M.D., and Philip Johnson, M.D., of the Chinese University of Hong Kong, and their colleagues measured plasma EBV DNA in patients with NPC 6 to 8 weeks after their treatment with radiotherapy was completed. They found that patients with higher levels of EBV DNA after treatment appeared to have poorer outcomes. In contrast, patients who had lower levels of EBV DNA after treatment appeared to have a much better chance at survival.
Note: The Journal of the National Cancer Institute is published by Oxford University Press and is not affiliated with the National Cancer Institute. Attribution to the Journal of the National Cancer Institute is requested in all news coverage.