To estimate the global attributable fraction of human papillomavirus (HPV) in lung cancer, we provided updated information through a system review and meta-analysis. We did a literature search on PubMed, Ovid and Web of Science to identify case-control studies and cohort studies that detected HPV in lung carcinomas. We included studies that tested 30 or more cases and were published before Feb 28, 2017. We collected information about gender, smoking status, HPV detection methods, HPV types, materials and clinical features. If it was not possible to abstract the required information directly from the papers, we contacted the authors. A meta-analysis was performed to calculate the pooled effect sizes (OR/RR) with 95% confidence intervals (CI) including subgroup analysis and meta-regression to explore sources of heterogeneity, by Stata 13.0 software. 36 case-control studies, contributing data for 6,980 cases of lung cancer and 7,474 controls from 17 countries and one cohort study with 24,162 exposed and 1,026,986 unexposed from China were included. HPV infection was associated with cancer of lung, pooled OR was 3.64 (95% CI: 2.60–5.08), calculated with the random-effects model. Pooled OR for allogeneic case-control studies, self-matched case-control studies and nested case-control studies were 6.71 (95% CI: 4.07–11.07), 2.59 (95% CI: 1.43–4.69) and 0.92 (95% CI: 0.63–1.36), respectively. Pooled OR for HPV 16 and HPV 18 infection, were 3.14 (95% CI: 2.07–4.76) and 2.25 (95% CI: 1.49–3.40), respectively. We also found that HPV infection may be associated with squamous cell carcinoma, adenocarcinoma and small cell carcinoma. There is evidence that HPV infection, especially HPV 16 and HPV 18 infection, significantly increase the risk of lung cancer. Future research needs to focus attention toward whether an HPV vaccine can effectively reduce the incidence of lung cancer.

Objective: Nasopharyngeal carcinoma is one of the leading malignancies with obscure etiology. Circulating tumor cells have been showed to intimately correlate with characteristics in different kinds of cancer. But links between circulating tumor cells and nasopharyngeal carcinoma were still lacking. Therefore, we explored circulating tumor cells' distribution in nasopharyngeal carcinoma and their possible associations with nasopharyngeal carcinoma. Methods: Firstly, we found that the positive ratio of circulating tumor cells is extremely high in four stages of nasopharyngeal carcinoma. Meanwhile, positive ratios of mesenchymal circulating tumor cells were higher in early stages of nasopharyngeal carcinoma. Apart from epithelial circulating tumor cells, total, hybrid and mesenchymal circulating tumor cells were correlated with nasopharyngeal carcinoma clinical stage. Results: Our results showed that hybrid and mesenchymal circulating tumor cells were associated with nasopharyngeal carcinoma metastasis (both distant and lymph node) and smoking. Meanwhile, hybrid circulating tumor cells expressed the highest Epstein-Barr virus proteins and deoxyribonucleic acid in three types of circulating tumor cells. Moreover, we found that Epstein-Barr virus proteins viral-caspid antigen-immunoglobulin A (VCA/IgA) and early antigen-immunoglobulin A (EA/IgA), but not Epstein-Barr virus-deoxyribonucleic acid, had a closed association with nasopharyngeal carcinoma metastasis. However, Epstein-Barr virus hallmarks failed to associate with other nasopharyngeal carcinoma characteristics. Furthermore, we confirmed that matrix metalloproteinase 9 existed in circulating tumor cells and expressed most in mesenchymal circulating tumor cells. In addition, matrix metalloproteinase 9-expressed extent in hybrid circulating tumor cells is somewhat different from epithelial and mesenchymal circulating tumor cells in matrix metalloproteinase 9-positive circulating tumor cells. Nevertheless, matrix metalloproteinase 9 had no relationship with other nasopharyngeal carcinoma characteristics. Finally, our results showed that circulating tumor cells were decreased in patients after therapies. carcinoma metastasis. Of note, decreased circulating tumor cells indicated a favorable curative effect in nasopharyngeal carcinoma patients.

The aim of this study was to investigate the association of menstrual and reproductive factors with risk of lung cancer in women. Potential etiological clues related to lung cancer in women are identified to inform preventive strategies.Case–control study of 477 newly diagnosed women with lung cancer and 479 age-matched (±2 years) controls. Data on menstrual and reproductive factors and history of oral contraceptive use were obtained on personal interviews using a structured questionnaire. Risk factors were analyzed by unconditional logistic regression analysis.Maternal age ≥25 years at first birth appeared to protect against female lung cancer [odds ratios (ORs): 0.511, 95% confidence interval (CI), 0.376–0.693]. Age at menopause > 50 years and use of contraceptives was associated with an increased risk of lung cancer in women (OR: 1.471, 95% CI, 1.021–2.119 and OR: 1.844, 95% CI: 1.111–3.061, respectively). Age ≥13 years at menarche was associated with a decreased risk of lung adenocarcinoma (OR: 0.563, 95% CI, 0.317–0.997). There was significant heterogeneity in the levels of cooking oil fume (COF) exposure (Pheterogeneity = .015). Higher levels of exposure to passive smoking, COF, and lack of tea intake were associated with an increased risk of lung cancer.Menstrual and reproductive factors are considered to play a role in the development of lung cancer in women. Exposure to passive smoking, COF, and lack of tea intake appeared to significantly modify the relationship.

BackgroundWe investigated whether BCMO1 variants and dietary patterns are associated with lung cancer risk.MethodsCase-control study including 1166 lung cancer cases and 1179 frequency matched controls was conducted for three BCMO1 variants (rs6564851, rs12934922, and rs7501331) and four dietary patterns were investigated. Logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (95% CIs).ResultsThe rs6564851, rs12934922, and rs7501331 were not found to be associated with lung cancer risk (P > 0.05). In multivariable-adjusted models, compared to the lowest quartile of the score on the “fruits and vegetables” pattern, the highest quintile was associated with a 78.4% decreased risk (OR Q4 vs. Q1 = 0.216; 95% CI, 0.164–0.284; P for trend < 0.001). Other patterns were not found the association. The “fruits and vegetables” pattern was associated with a reduced risk of lung cancer with all 3 SNPs irrespective of genotypes (all P for trend< 0.001). The association for the “Frugal” pattern was associated with increased risk of lung cancer among smokers (P for interaction = 0.005). The protective effects of the “cereals/wheat and meat” pattern was more evident for squamous cell carcinoma and other histological type.ConclusionsWe did not observe associations of BCMO1 variants and lung cancer. Diets rich in fruits and vegetables may be protective against lung cancer.Electronic supplementary materialThe online version of this article (10.1186/s12885-018-4361-2) contains supplementary material, which is available to authorized users.

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