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Associations between telomere length and cancer risk have been investigated in many epidemiological studies, but the results are controversial. These associations may be biased by reverse causation or confounded by environmental exposures. To avoid potential biases, we used Mendelian randomization method to evaluate whether TL is the causal risk factor for lung cancer. We conducted Mendelian randomization analysis in two published East Asian GWAS studies (7127 cases and 6818 controls). We used both weighted genetic risk score and inverse‐variance weighting method to estimate the relationship between TL and lung cancer risk. Nonlinear test also used to detect potential association trends. We observed that increased weight GRS was associated with increased risk of lung cancer (OR = 2.25, 95%CI: 1.81‐2.78, P = 1.18 × 10−13). In different subtypes, weight GRS was significantly associated with lung adenocarcinoma risk (OR = 2.69, 95% CI: 2.11‐3.42, P = 7.20 × 10−16); while lung squamous cell carcinoma showed a marginal association (OR = 1.45, 95% CI = 1.01‐2.10, P = .047). Nonlinear analysis suggested a log‐linear dose‐response relationship between increased weight GRS and lung cancer risk. Our results indicated that longer TL increases lung cancer risk. Those biological mechanisms changes caused by long TL may play an important role in lung carcinogenesis. [ABSTRACT FROM AUTHOR]

Background: Although high‐risk human papillomavirus (HR‐HPV) infection is recognized as the main cause of cervical cancer, only a minority of HPV‐infected women develop this malignancy. Increasing evidence suggests that alterations of telomere length might be implicated in carcinogenesis. However, the association between cervical cancer and telomere length remains unknown. Methods: This case‐control study included 591 cervical cancer patients and 373 cancer‐free controls, all of whom were infected with HR‐HPV. Relative telomere length (RTL) in cervical cancer exfoliated cells was measured by quantitative PCR. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated by logistic regression analysis. Results: HPV16, 18, 52, and 58 were common in both case and control groups. The proportion of HPV16 infection tended to increase across the quartiles of RTL (Ptrend < 0.001). There was no statistically significant association of RTL with tumor differentiation, histological type, and FIGO stage. After adjustment for age and HPV types, the lowest quartile of RTL presented a 49% lower risk (OR = 0.51, 95% CI: 0.35, 0.76; P < 0.001) than those with the highest quartile of RTL. There was also a dose‐response relationship of shorter RTL on lower risk of cervical cancer (Ptrend < 0.001). Conclusion: Shortened telomere length in cervical exfoliated cells was related to the lower risk of cervical cancer among HR‐HPV‐positive women, which might help to improve cervical cancer screening and surveillance. Further prospective studies with large sample should be designed to validate our preliminary findings, and evaluate the potential efficacy of telomere length for cervical cancer screening. New triage biomarkers for human papillomavirus‐positive women are necessary to improve the identification of individuals at high risk of cervical cancer progression. Shorter telomere length in cervical exfoliated cells was associated with the lower risk of cervical cancer. Shortened telomere length may act as a protective factor in cervical carcinogenesis and represent a potential biomarker for this malignancy. [ABSTRACT FROM AUTHOR]