Calpeptin may reverse glucocorticoid-resistance of allergic rhinitis associated with cigarette smoke exposure by down-regulating interferon regulatory factor 1.

Cigarette smoke exposure is an important factor in chronic inflammation in patients with allergic rhinitis (AR); however, the relationship between cigarette smoke and AR-related glucocorticoid resistance requires further study. In mice, calpeptin significantly reduces inflammation of the lower respiratory tract caused by cigarette smoke, but whether it can treat glucocorticoid-resistant AR caused by cigarette smoke requires further research. In this study, we confirmed that cigarette smoke exposure can aggravate the Th2 inflammatory response in AR leading to glucocorticoid resistance. The underlying mechanism may be related to decreased expression of DNA methyltransferase 3a (Dnmt3a), and increased expression of interferon regulatory factor 1 (IRF1). In addition, we found that calpeptin can inhibit the expression of IRF1 and thus treat AR-associated glucocorticoid resistance in rats exposed to cigarette smoke. These data suggest that calpeptin may downregulate IRF1 and therefore treat glucocorticoid resistance in AR-associated with cigarette smoke exposure.

Characteristics of cigarette smoking without alcohol consumption and laryngeal cancer: overall and time-risk relation. A meta-analysis of observational studies.

Tobacco smoking was one of the risk factors for upper aerodigestive tract cancer, but exclusive quantification of the impact of cigarette smoking on laryngeal cancer had not been investigated. A meta-analysis of researches that had reported quantitative estimates of cigarette smoking and risk of laryngeal cancer by March 2016 was performed. Pooled estimates of relative risks and their 95% confidence intervals were obtained and summarized. Sensitivity analysis and subgroup analysis were implemented to find out sources of research heterogeneity and the effect of potential confounders. Publication bias was investigated and corrected if found to be present through Egger's and Begg's test, and trim and fill algorithm. Thirty researches based on a total of 14,292 cases from three cohort and fifteen case-control studies were included and pooled estimate for the correlation between cigarette smoking and the risk of laryngeal cancer was 7.01 (95% confidence interval 5.56-8.85), with moderate heterogeneity across the researches (I 2 = 56.7%, p = 0.002). The RRs were 5.04 (95% CI 3.09-8.22) for cohort studies (p = 0.121), 7.59 (95% CI 5.86-9.82) for case-control studies (p = 0.005). The risk kept elevated within the first fifteen years of quitting smoking(RR 3.62, 95% CI 1.88-7.00) but dropped in the 16 years and more after smoking cessation(RR 1.88, 95% CI 1.16-3.05). Individuals who smoked with 40 or more pack-years had nine times the risk of laryngeal cancer(RR 9.14; 95% CI 6.24-13.39). Subjects who smoked 30 or more cigarettes a day had sevenfolds the risk of laryngeal cancer (RR 7.02; 95% CI 4.47-11.02) and who smoked 40 or more years had five times the risk versus never smokers (RR 5.76; 95% CI 3.69-8.99). Evidence of publication bias was not detected for the correlation between current cigarette smoking and risk of laryngeal cancer (p = 0.225 with Begg's test, p = 0.317 with Egger's test). The results demonstrated strong correlation referring to dose-response and time-response between cigarette smoking and risk of laryngeal cancer for both men and women. The probability of developing laryngeal cancer was decreased by quitting smoking, particularly among former cigarette smokers who had stopped smoking for 15 or more years. The subgroup analysis demonstrated that study type influenced the RRs estimates of the studies.