Soy and tea intake on cervical cancer risk: the Singapore Chinese Health Study.

PURPOSE: Soy isoflavones and tea catechins have immunomodulating and chemopreventive properties relevant for cervical carcinogenesis; however, there are limited epidemiologic data on the relationship of soy and tea consumption with cervical cancer risk. The aim of our study was to examine effects of soy and tea intake on cervical cancer risk among Singapore Chinese women. METHODS: The association between intake of soy and tea drinking and cervical cancer risk was investigated in a prospective, population-based cohort of 30,744 Chinese women in Singapore with an average 16.7 years of follow-up and 312 incident cervical cancer cases. Multivariable proportional hazard models were used to estimate hazard ratio (HR) and 95% confidence interval (CI) of cervical cancer associated with intake levels of soy and tea. RESULTS: High intake of soy alone was associated with a statistically borderline significant 20% reduced risk of cervical cancer (HR 0.80, 95% CI 0.61, 1.05) while green tea alone was not (HR 0.97, 95% CI: 0.76, 1.22). In stratified analysis, high intake of soy was associated with a statistically significant decrease in cervical cancer risk among green tea drinkers (HR 0.43; 95% CI 0.28, 0.69) but not among non-drinkers of green tea. The difference in the soy-cervical cancer risk association between green tea drinkers and non-drinkers was statistically significant (p for interaction = 0.004). This inverse association between soy intake and cervical cancer risk remained after further adjustment for human papillomavirus serostatus. Black tea consumption was not associated with cervical cancer risk. CONCLUSIONS: These findings suggest that a protective effect of soy against cervical cancer development may depend on green tea constituents.

Opium: an emerging risk factor for gastric adenocarcinoma.

Opium use has been associated with higher risk of cancers of the esophagus, bladder, larynx, and lung; however, no previous study has examined its association with gastric cancer. There is also little information on the associations between hookah (water pipe) smoking or the chewing of tobacco products and the risk of gastric cancer. In a case-control study in Golestan Province of Iran, we enrolled 309 cases of gastric adenocarcinoma (118 noncardia, 161 cardia and 30 mixed-location adenocarcinomas) and 613 matched controls. Detailed information on long-term use of opium, tobacco products and other covariates were collected using structured and validated lifestyle and food frequency questionnaires. Odds ratios (ORs) and 95% confidence intervals (95% CIs) were obtained using conditional logistic regression models. Opium use was associated with an increased risk of gastric adenocarcinoma, with an adjusted OR (95% CI) of 3.1 (1.9-5.1), and this increased risk was apparent for both anatomic subsites (cardia and noncardia). There was a dose-response effect, and individuals with the highest cumulative opium use had the strongest association (OR: 4.5; 95% CI: 2.3-8.5). We did not find a statistically significant association between the use of any of the tobacco products and risk of gastric adenocarcinoma, overall or by anatomic subsite. We showed, for the first time, an association between opium use and gastric adenocarcinoma. Given that opium use is a traditional practice in many parts of the world, these results are of public health significance.

Evaluation of different glutathione S-transferase-tagged protein captures for screening E6/E6AP interaction inhibitors using AlphaScreen.

Human papillomavirus (HPV) infection is responsible for the development of cervical cancer and its premalignant lesions in women. The virus-encoded oncogene E6 is a promising target for an anti-HPV drug therapy. The authors describe the development of a homogenous screening assay for inhibitors of the E6 interaction with its cellular target, the E6-associated protein (E6AP), based on AlphaScreen technology. The E6 protein was expressed and purified as glutathione S-transferase (GST) fusion protein, and the binding to a biotinylated E6AP peptide was monitored using GST-detecting Acceptor beads coated either with anti-GST antibody or glutathione. After optimization of the assay conditions, a commercial library of 3000 compounds was screened for inhibitors. Active compounds were retested and counterscreened for E6/E6AP specificity using biotinylated GST as a control protein. The results obtained with both types of GST-detecting reagents correlated very well and demonstrated the great potential of the newly developed glutathione-coated Acceptor beads as a detection reagent for GST fusion proteins.