Dietary Nutrient Intake, Ethnicity, and Epigenetic Silencing of Lung Cancer Genes Detected in Sputum in New Mexican Smokers

Vitamin K Intake and Risk of Lung Cancer: The Japan Collaborative Cohort Study

BACKGROUND

Limited reports from prospective human studies investigated the possible role of vitamin K in the development of lung cancer although vitamin K's anticarcinogenic activities were verified from several in vitro and in vivo studies. We investigated the associations between total vitamin K intake from food and the development of lung cancer based on this large prospective cohort study.

METHODS

A validated food frequency questionnaire was used to examine vitamin K intake among 42,166 (16,341 men and 25,825 women) at the Japan Collaborative Cohort Study's baseline (1988-1990). Hazard ratios (HRs) and 95% confidence intervals (CIs) of incident lung cancer were calculated using the Cox proportional hazard regression method based on vitamin K consumption quartiles.

RESULTS

430 cases (308 males and 122 women) of lung cancer were documented during a total of 564,127 person-years of follow-up (median follow-up, 14.6 years). Vitamin K consumption was shown to be inversely related to lung cancer risk; the multivariable hazard ratio [HR] for the highest versus lowest quartiles was 0.67 (95% confidence interval [CI], 0.46-0.96; P for trend = 0.010). This relationship appears to be stronger in males (HR 0.62; 95% CI, 0.40-0.96; P for trend = 0.016) than in females (HR 0.82; 95% CI, 0.42-1.61; P for trend = 0.39) (P for interaction = 0.012), and in ever smokers (HR 0.57; 95% CI, 0.36-0.91; P for trend = 0.006) than in never smokers (HR 0.79; 95% CI, 0.40-1.55; P for trend = 0.37) (P for interaction = 0.30). The individuals' age, body mass index, or alcohol consumption status had no effect on the observed connection.

CONCLUSION

Vitamin K consumption reduces the risk of lung cancer. More research is needed to clarify the molecular processes behind this connection.

Racial/ethnic disparities in gastric cancer: A 15-year population-based analysis

BACKGROUND AND AIMS

Disparities in gastric cancer incidence and mortality have been reported among ethnic/racial groups. While gastric cancer is not common in the U.S., it is among the top 10 causes of cancer-related death among Hispanics living in Puerto Rico (PRH). This study compared gastric cancer incidence rates during a 15-year period (2002-2006, 2007-2011, and 2012-2016) between PRH and racial/ethnic groups in the mainland U.S., including Non-Hispanic Whites (NHW), Non-Hispanics Blacks (NHB), Hispanics (USH), and Non-Hispanic Asian or Pacific Islanders (NHAPI).

METHODS

Primary gastric cancer cases (ICD-O-3 codes C16.0 to C16.9) from the Puerto Rico Central Cancer Registry and SEER diagnosed from January 1, 2002 to December 31, 2016 were included in the analysis. The Joinpoint Regression Program and standardized rate ratios were used to estimate Annual Percent Changes (APC) and differences in gastric cancer incidence among racial/ethnic groups, respectively.

RESULTS

Our analysis included 83,369 gastric cancer cases (PRH n = 4202; NHW n = 43,164; NHB n = 10,414; NHAPI n = 11,548; USH n = 14,041). USH had the highest number of cases among individuals <50 years, whereas NHW and PRH had the highest percentage among individuals ≥50 years. PRH and USH were the only groups with increasing APCs among individuals <50 years.

CONCLUSIONS

Gastric cancer continues to be a common cancer among PRH, despite the overall decrease in incidence among other racial/ethnic groups. Studies evaluating the gastric cancer risk factors among high-risk groups are necessary to establish health policy and modify gastric cancer screening algorithms among Hispanics.

Circulatory metabolites trigger ex vivo arterial endothelial cell dysfunction in population chronically exposed to diesel exhaust

Background

Chronic exposure to diesel exhaust has a causal link to cardiovascular diseases in various environmental and occupational settings. Arterial endothelial cell function plays an important role in ensuring proper maintenance of cardiovascular homeostasis and the endothelial cell dysfunction by circulatory inflammation is a hallmark in cardiovascular diseases. Acute exposure to diesel exhaust in controlled exposure studies leads to artery endothelial cells dysfunction in previous study, however the effect of chronic exposure remains unknown.

Results

We applied an ex vivo endothelial biosensor assay for serum samples from 133 diesel engine testers (DETs) and 126 non-DETs with the aim of identifying evidence of increased risk for cardiovascular diseases. Environmental monitoring suggested that DETs were exposed to high levels of diesel exhaust aerosol (282.3 μg/m³ PM_2.5 and 135.2 μg/m³ elemental carbon). Surprisingly, chronic diesel exhaust exposure was associated with a pro-inflammatory phenotype in the ex vivo endothelial cell model, in a dose-dependent manner with CCL5 and VCAM as most affected genes. This dysfunction was not mediated by reduction in circulatory pro-inflammatory factors but significantly associated with a reduction in circulatory metabolites cGMP and an increase in primary DNA damage in leucocyte in a dose-dependent manner, which also explained a large magnitude of association between diesel exhaust exposure and ex vivo endothelial biosensor response. Exogenous cGMP addition experiment further confirmed the induction of ex vivo biosensor gene expressions in endothelial cells treated with physiologically relevant levels of metabolites cGMP.

Conclusion

Serum-borne bioactivity caused the arterial endothelial cell dysfunction may attribute to the circulatory metabolites based on the ex vivo biosensor assay. The reduced cGMP and increased polycyclic aromatic hydrocarbons metabolites-induced cyto/geno-toxic play important role in the endothelial cell dysfunction of workers chronic exposure to diesel exhaust.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12989-022-00463-0.

The Potential Role of Nutrition in Lung Cancer Establishment and Progression

Lung cancer is a devastating disease with a high incidence and low survival rates, so recent studies have focused on analyzing the risk factors that might prevent this disease from developing or have protective/therapeutic effects. Nutrition is an important key factor in the prevention and treatment of lung cancer. Various factors appear to be involved in the development of the latter, such as cigarette smoking or certain external environmental factors. The increase in oxidative stress is therefore an integral part of the carcinogenesis process. The biological role of bioactive factors derived from adipose tissue, mainly adipokines, is implicated in various cancers, and an increasing body of evidence has shown that certain adipocytokines contribute to the development, progression and prognosis of lung cancer. Not all adipokines stimulate tumor growth; in fact, adiponectin inhibits carcinogenesis by regulating both cell growth and the levels of inflammatory cytokines. Adiponectin expression is deregulated in several cancer types. Many nutritional factors have been shown to increase adiponectin levels and therefore could be used as a new therapeutic strategy for combating lung cancer. In addition, foods with antioxidant and anti-inflammatory properties play a key role in the prevention of many human diseases, including lung cancer. The purpose of this review is to analyze the role of diet in lung cancer in order to recommend dietary habit and lifestyle changes to prevent or treat this pathology.

Frequent DNA methylation changes in cancerous and noncancerous lung tissues from smokers with non-small cell lung cancer

Cancer deaths account for nearly 10 million deaths worldwide each year, with lung cancer (LCa) as the leading cause of cancer-related death. Smoking is one of the major LCa risk factors, and tobacco-related carcinogens are potent mutagens and epi-mutagens. In the present study, we aimed to analyse smoking-related epigenetic changes in lung tissues from LCa cases. The study cohort consisted of paired LCa and noncancerous lung tissues (NLT) from 104 patients, 90 of whom were smokers or ex-smokers (i.e. ever smokers) at the time of diagnosis. DNA methylation status of tumour suppressor genes DAPK1, MGMT, p16, RASSF1 and RARB was screened by means of methylation-specific PCR (MSP) and further analysed quantitatively by pyrosequencing. Methylation of at least one gene was detected in 59% (61 of 104) of LCa samples and in 39% (41 of 104) of NLT. DAPK1 and RASSF1 were more frequently methylated in LCa than in NLT (P = 0.022 and P = 0.041, respectively). The levels of DNA methylation were higher in LCa than NLT at most of the analysed CpG positions. More frequent methylation of at least one gene was observed in LCa samples of ever smokers (63%, 57 of 90) as compared with never smokers (36%, 5 of 14; P = 0.019). In the ever smokers group, methylation of the genes also occurred in NLT, but was rare or absent in the samples of never smokers. Among the current smokers, RASSF1 methylation in LCa showed association with the number of cigarettes smoked per day (P = 0.017), whereas in NLT it was positively associated with the duration of smoking (P = 0.039). Similarly, p16 methylation in LCa of current smokers correlated with the larger number of cigarettes smoked per day (P = 0.047). Overall, DNA methylation changes were present in both cancerous and noncancerous tissues of LCa patients and showed associations with smoking-related parameters.

How Dietary Factors Affect DNA Methylation: Lesson from Epidemiological Studies

Over the past decades, DNA methylation has been proposed as a molecular mechanism underlying the positive or negative effects of diet on human health. Despite the number of studies on this topic is rapidly increasing, the relationship between dietary factors, changes in DNA methylation and health outcomes remains unclear. In this review, we summarize the literature from observational studies (cross-sectional, retrospective, or prospective) which examined the association of dietary factors (nutrients, foods, and dietary patterns) with DNA methylation markers among diseased or healthy people during the lifetime. Next, we discuss the methodological pitfalls by examining strengths and limitations of published studies. Finally, we close with a discussion on future challenges of this field of research, raising the need for large-size prospective studies evaluating the association between diet and DNA methylation in health and diseases for appropriate public health strategies.

Potential Micronutrients and Phytochemicals against the Pathogenesis of Chronic Obstructive Pulmonary Disease and Lung Cancer

Lung cancer and chronic obstructive pulmonary disease have shared etiology, including key etiological changes (e.g., DNA damage and epigenetics change) and lung function impairment. Focusing on those shared targets may help in the prevention of both. Certain micronutrients (vitamins and minerals) and phytochemicals (carotenoids and phenols) have potent antioxidant or methyl-donating properties and thus have received considerable interest. We reviewed recent papers probing into the potential of nutrients with respect to lung function preservation and prevention of lung cancer risk, and suggest several hypothetical intervention patterns. Intakes of vitamins (i.e., A, C, D, E, B₁₂), carotenoids, flavonoids, curcumins, resveratrol, magnesium, and omega-3 fatty acids all show protective effects against lung function loss, some mainly by improving average lung function and others through reducing decline rate. Dietary interventions early in life may help lung function reserve over the lifespan. Protective nutrient interventions among smokers are likely to mitigate the effects of cigarettes on lung health. We also discuss their underlying mechanisms and some possible causes for the inconsistent results in observational studies and supplementation trials. The role of the lung microbiome on lung health and its potential utility in identifying protective nutrients are discussed as well. More prospective cohorts and well-designed clinical trials are needed to promote the transition of individualized nutrient interventions into health policy.