Smoking-related cancer death among men and women in an ageing society (China 2020-2040): a population-based modelling study

The spectrum of TP53 mutations in Rwandan patients with gastric cancer

BACKGROUND

Gastric cancer is the sixth most frequently diagnosed cancer and third in causing cancer-related death globally. The most frequently mutated gene in human cancers is TP53, which plays a pivotal role in cancer initiation and progression. In Africa, particularly in Rwanda, data on TP53 mutations are lacking. Therefore, this study intended to obtain TP53 mutation status in Rwandan patients with gastric cancer.

RESULTS

Formalin-fixed paraffin-embedded tissue blocks of 95 Rwandan patients with histopathologically proven gastric carcinoma were obtained from the University Teaching Hospital of Kigali. After DNA extraction, all coding regions of the TP53 gene and the exon-intron boundary region of TP53 were sequenced using the Sanger sequencing. Mutated TP53 were observed in 24 (25.3%) of the 95 cases, and a total of 29 mutations were identified. These TP53 mutations were distributed between exon 4 and 8 and most of them were missense mutations (19/29; 65.5%). Immunohistochemical analysis for TP53 revealed that most of the TP53 missense mutations were associated with TP53 protein accumulation. Among the 29 mutations, one was novel (c.459_477delCGGCACCCGCGTCCGCGCC). This 19-bp deletion mutation in exon 5 caused the production of truncated TP53 protein (p.G154Wfs*10). Regarding the spectrum of TP53 mutations, G:C > A:T at CpG sites was the most prevalent (10/29; 34.5%) and G:C > T:A was the second most prevalent (7/29; 24.1%). Interestingly, when the mutation spectrum of TP53 was compared to three previous TP53 mutational studies on non-Rwandan patients with gastric cancer, G:C > T:A mutations were significantly more frequent in this study than in our previous study (p = 0.013), the TCGA database (p = 0.017), and a previous study on patients from Hong Kong (p = 0.006). Even after correcting for false discovery, statistical significance was observed.

CONCLUSIONS

Our results suggested that TP53 G:C > T:A transversion mutation in Rwandan patients with gastric cancer is more frequent than in non-Rwandan patients with gastric cancer, indicating at an alternative etiological and carcinogenic progression of gastric cancer in Rwanda.

Knowledge and awareness of nicotine, nicotine replacement therapy, and electronic cigarettes among general practitioners with a special interest in respiratory medicine in China

Objectives

This study aimed to assess the knowledge and awareness of nicotine, nicotine replacement therapy (NRT), and electronic cigarettes (e-cigarettes) among general practitioners with a special interest (GPwSIs) in respiratory medicine.

Methods

A cross-sectional study was conducted from October 2021 to February 2022. Knowledge and awareness were compared among smokers and non-smokers, as well as different age and gender groups.

Results

The study consisted of 102 GPwSIs from 21 cities in Sichuan Province, China. Most respondents would recommend NRT for long-term use. Only a few believed that e-cigarettes are an effective means of smoking cessation and 71.6% would not recommend e-cigarettes as a substitute for cigarettes to their patients. Additionally, the majority did not regularly provide extensive help to assist patients in quitting smoking and needed smoking cessation counseling training.

Conclusion

GPwSIs in respiratory medicine in China could have a relatively low level of knowledge and awareness regarding nicotine, NRT, and e-cigarettes. The study highlights the need for smoking cessation training among GPwSIs to improve their knowledge and provide better assistance to patients who want to quit smoking.

Dose-response relationship between active smoking and lung cancer mortality/prevalence in the Chinese population: a meta-analysis

BACKGROUND

The dose‒response relationship-based relative risk (RR) of smoking exposure could better predict the risk of lung cancer than the dichotomous RR. To date, there is a lack of large-scale representative studies illustrating the dose‒response relationship between smoking exposure and lung cancer deaths, and no study has systematically pooled the current evidence in the Chinese population.

OBJECTIVES

To elucidate the dose‒response relationship of smoking and the risk of lung cancer mortality in the Chinese population.

METHODS

Data were derived from studies on dose‒response relationships of smoking exposure and the risk of lung cancer among Chinese adults published before June 30^th, 2021. Based on smoking exposure indicators and RR of lung cancer mortality, a series of dose‒response relationship models were developed. For smokers, 10 models were built to fit the dose‒response relationships between pack-years and RR of lung cancer deaths. For quitters, quit-years and corresponding RRs were used, and the pooled dichotomous RR value was used as the starting point to avoid overestimation. Finally, the results were compared with the estimates from 2019 Global Burden of Disease (GBD) study.

RESULTS

A total of 12 studies were included. Among 10 dose‒response relationship models of pack-years with the RR of lung cancer mortality, the integrated-exposure-response (IER) model achieved the best fit. In all models, less than 60 pack-years presented RRs below 10. For former smokers, the RR decreased to 1 when quit-years reached up to 7 years. Both smokers and quitters had much lower RRs than that of the global level estimated by GBD.

CONCLUSION

The risk of lung cancer mortality rose with pack-years and decreased with quit-years among Chinese adults, and both values were far below global level. The results suggested that the dose-response RR of lung cancer deaths associated with smoking in China should be estimated separately.

Gender differences in social environmental changes associated with smoking: a cross-sectional study from Chinese internal migrants

OBJECTIVES

To identify clues for women's tobacco control, this study analyses the gender differences in social environmental changes associated with smoking and the interaction between the environment and individuals' social integration.

DESIGN, SETTING AND PARTICIPANTS

A cross-sectional design and secondary analysis were used among Chinese internal migrants. Data were from the 2012 Migrant Dynamics Monitoring Survey in China with participants aged 15-59 years old (75 416 women and 83 140 men) who resided in cities for more than 1 month.

PRIMARY AND SECONDARY OUTCOME MEASURES

Social environmental changes were measured by differences in smoking prevalence and women's empowerment between the migrant-receiving province (MRP) and migrant-sending province (MSP). Social participation and duration of stay (DOS) were adopted as indicators of social integration. Stratified analysis and binary logistic regression models were used to determine the dependent variable (smoking status) and environmental changes after controlling for age, education, income and happiness.

RESULTS

Differences in the smoking prevalence environment (lower in MRP, OR 0.70, 95% CI 0.60 to 0.83; higher rate in MRP, OR 1.79, 95% CI 1.35 to 2.37) and women's empowerment (lower rate in MRP, OR 0.80, 95% CI 0.68 to 0.97; higher rate in MRP, OR 1.15, 95% CI 1.00 to 1.33) between MRP and MSP were positively correlated with women's smoking. In men, however, migrating to an area with lower smoking prevalence could not reduce smoking risk, whereas moving to an area with higher women's empowerment could. A long DOS was an independent risk factor for smoking in women (ranged from 1.20 to 2.00 in various environmental changes scenarios) but a protective factor for men. An interaction between environmental changes and social integration could not be verified.

CONCLUSIONS

Tobacco control strategies should consider gender differences, especially women who are experiencing social environmental changes.

Dynamics of PD-1 expression are associated with treatment efficacy and prognosis in patients with intermediate/high-risk myelodysplastic syndromes under hypomethylating treatment

Hypomethylating agents (HMAs) are widely used in patients with higher-risk MDS not eligible for stem cell transplantation. However, the general response rate by HMAs is lesser than 50% in MDS patients, while the relapse rate is high. Emerging evidence indicates that demethylating effects committed by HMAs may facilitate the up-regulation of a range of immune checkpoints or cancer suppressor genes in patients with MDS, among which the programmed death protein 1 (PD-1) and its ligands are demonstrated to be prominent and may contribute to treatment failure and early relapse. Although results from preliminary studies with a limited number of enrolled patients indicate that combined administration of PD-1 inhibitor may yield extra therapeutic benefit in some MDS patients, identifications of this subgroup of patients and optimal timing for the anti-PD-1 intervention remain significant challenges. Dynamics of immune checkpoints and associated predictive values during HMA-treatment cycles remained poorly investigated. In this present study, expression levels of immune checkpoints PD-1 and its ligands PD-L1 and PD-L2 were retrospectively analyzed by quantitative PCR (Q-PCR) in a total of 135 myelodysplastic syndromes (MDS) cohort with higher-risk stratification. The prognostic value of dynamics of these immune checkpoints during HMA cycles was validated in two independent prospective cohorts in our center (NCT01599325 and NCT01751867). Our data revealed that PD-1 expression was significantly higher than that in younger MDS patients (age ≤ 60) and MDS with lower IPSS risk stratification (intermediate risk-1). A significantly up-regulated expression of PD-1 was seen during the first four HMA treatment cycles in MDS patients, while similar observation was not seen concerning the expression of PD-L1 or PD-L2. By utilizing binary logistic regression and receiver operating characteristic (ROC) models, we further identified that higher or equal to 75.9 PD-1 expressions after 2 cycles of HMA treatment is an independent negative prognostic factor in predicting acute myeloid leukemia (AML) transformation and survival. Collectively, our data provide rationales for monitoring the expression of PD-1 during HMA treatment cycles, a higher than 75.9 PD-1 expression may identify patients who will potentially benefit from the combined therapy of HMA and PD-1 inhibitors.

Diabetes associated with cervical carcinoma among high-risk HPV-infected patients with cytologically diagnosed high grade squamous intraepithelial lesion

BACKGROUND

Diabetes causes metabolic disorders and immune changes that may be potential triggers of cervical cancer. Therefore, diabetes is not a "bystander" to cervical cancer. However, the conclusion that diabetes promotes cervical cancer lacks clinical epidemiological evidence, and the reported potential association between diabetes and cervical cancer is controversial.

METHODS

We conducted an explorative cross-sectional study of 791 women with cytological HGSIL and HR-HPV, who attended the cervical clinic of the largest academic women's hospital in China from May 2019 to March 2022. After cervical screening, patients who were requiring colposcopy were tested for HbA1c. HbA1c level of 6.5% or higher defines diabetes and HbA1c level of 5.7%-6.4% was defined as prediabetes. The relationship between diabetes and cervical cancer was observed by a dose-response graph. Subgroup analysis and multivariate logistic regression analysis were conducted to estimate the associations between diabetes and cervical cancer.

RESULTS

Among HGSIL patients with high-risk HPV infection, compared with women with HbA1c <5.7%, the odds ratio for women with prediabetes was 1.72 (95% CI: 0.87-3.41) and the odds ratio for women with diabetes was 3.29 (95% CI: 1.10-9.80) for cervical cancer. Sensitivity analysis showed that diabetes was significantly associated with cervical cancer in different age groups and different HPV variant. E-value analysis showed robustness to unmeasured confounding.

CONCLUSIONS

In patients with HR-HPV combined with HGSIL, diabetes and prediabetes are associated with cervical cancer.

Diabetes associated with HPV infection in women aged over 50 years: A cross-sectional study from China's largest academic woman's hospital

BACKGROUND

Metabolic disturbances and immune alterations caused by diabetes are not just bystanders of HPV infection, but the conclusion that diabetes increases the risk of HPV infection requires more clinical epidemiological evidence to confirm. Our aim was to evaluate the association of diabetes with HPV infection risk in female patients aged over 50 years in the cervical clinic.

METHODS

We conducted a cross-sectional study of 6402 women aged over 50 years in the cervical clinic between May 2019 and March 2022 from China's largest academic woman's hospital. The quantitative-effect relationship between diabetes and HPV infection was observed by dose-response graph. Segmented multivariate logistic regression analysis was conducted to estimate the relative risk of HPV infection in diabetes patients. Multivariable predicted marginal proportions from logistic regression models were used to compute adjusted risk ratios.

RESULTS

There is a nonlinear relationship between HbA1c and the risk of HPV infection. When the HbA1c exceeds 5.7%, there is a saturation effect. After adjustment for confounders, the risk ratio for HPV infection in women with prediabetes was 1.09 (95% CI: 1.00-1.18) compared with women with HbA1c <5.7%, and the risk ratio for HPV infection in women with diabetes was 1.18 (95%). CI: 1.04-1.33). Sensitivity analysis showed that the risk ratio for HPV infection was 1.47 (95% CL: 1.07-1.91) when diabetes was associated with vaginitis. E-value analysis suggested robustness to unmeasured confounding.

CONCLUSIONS

Diabetes and prediabetes are at increased risk of coinfection with HPV in female patients aged over 50 years in the cervical clinic.