Cigarette Smoking and p16INK4α Gene Promoter Hypermethylation in Non-Small Cell Lung Carcinoma Patients: A Meta-Analysis

BACKGROUND:Aberrant methylation of promoter DNA and transcriptional repression of specific tumor suppressor genes play an important role in carcinogenesis. Recently, many studies have investigated the association between cigarette smoking and p16(INK4α) gene hypermethylation in lung cancer, but could not reach a unanimous conclusion. METHODS AND FINDINGS:Nineteen cross-sectional studies on the association between cigarette smoking and p16(INK4α) methylation in surgically resected tumor tissues from non-small cell lung carcinoma (NSCLC) patients were identified in PubMed database until June 2011. For each study, a 2×2 cross-table was extracted. In total, 2,037 smoker and 765 nonsmoker patients were pooled with a fixed-effects model weighting for the inverse of the variance. Overall, the frequency of p16(INK4α) hypermethylation was higher in NSCLC patients with smoking habits than that in non-smoking patients (OR = 2.25, 95% CI = 1.81-2.80). The positive association between cigarette smoking and p16(INK4α) hypermethylation was similar in adenocarcinoma and squamous-cell carcinoma. In the stratified analyses, the association was stronger in Asian patients and in the studies with larger sample sizes. CONCLUSION:Cigarette smoking is positively correlated to p16(INK4α) gene hypermethylation in NSCLC patients

Foreign policy, bipartisanship and the paradox of post-September 11 America

The attacks of September 11 and the resulting war on terrorism present a puzzle to conventional explanations of foreign policy bipartisanship. Public anxiety about the international environment increased sharply after the attacks in 2001, but this did not translate into greater foreign policy consensus despite the initial predictions of many analysts. In this article, we advance a theory of foreign policy bipartisanship that emphasizes its domestic underpinnings to explain the absence of consensus in Washington. We argue that bipartisanship over foreign policy depends as much on domestic economic and electoral conditions as on the international security environment. Using multivariate analysis of roll call voting in the House of Representatives from 1889 to 2008, we show that bipartisanship over foreign policy is most likely not only when the country faces a foreign threat but also when the national economy is strong and when party coalitions are regionally diverse. This was the case during the Cold War. Despite concern about terrorism in recent years, economic volatility and regional polarization have made bipartisan cooperation over foreign policy elusive