June 2007 CEBP Highlights

Though substantial progress has been made toward reducing the prevalence of tobacco use in the U.S., the recent stabilization of adult and youth smoking rates underscores the need for continued vigorous research on nicotine dependence and tobacco control. This CEBP Focus section, guest edited by Drs. Caryn Lerman and Robert Schnoll, brings together experts who cover the following topics: prevention program design and implementation; the intermediate outcomes of a large-scale randomized tobacco prevention trial for youth in India; genetic contributions to individual differences in sensitivity to nicotine; pharmacogenetic research on smoking cessation that may provide a basis for tailored smoking cessation therapies; and tobacco industry knowledge about the health risks of smoking, and changes in industry activities since signing the Master Settlement Agreement. Finally, a commentary provides suggestions for future directions and research priorities in the nicotine and tobacco-control field.

 

Some studies suggest that elevated serum insulin-like growth factor-I (IGF-I) concentrations are associated with an increased risk of advanced-stage prostate cancer. Allen et al. analyzed the association between pre-diagnostic serum concentrations of IGF-I and IGFBP-3 and prostate cancer risk in a case-control study nested in the European Prospective Investigation into Cancer and Nutrition (EPIC). Their results showed that serum IGF-I concentration is not strongly associated with prostate cancer risk, although the results are compatible with a small increase in risk, in particular for advanced-stage disease which is consistent with the hypothesis that IGF may be related to tumor aggressiveness.

Although supplemental vitamin E (α-tocopherol) has been linked to lower prostate cancer incidence, the evidence regarding dietary intake of individual vitamin E isoforms and prostate cancer is limited and inconclusive. In the largest prospective cohort study to date, Wright et al. examined the relations of supplemental vitamin E and dietary intakes of α-, β-, γ-, and δ- tocopherols to prostate cancer risk among 295,344 men, aged 50 to 71 and cancer-free at enrollment. The authors found no overall association between vitamin E supplement use and prostate cancer. Higher consumption of dietary gamma-tocopherol was associated with significant reductions in advanced prostate cancer, providing support for continued research efforts directed towards this vitamin E isoform.