Betel quid chewing as an environmental risk factor for breast cancer

Short-term arecoline exposure affected the systemic health state of mice, in which gut microbes played an important role

Arecoline is a critical bioactive component in areca nuts with toxicity and pharmacological activities. However, its effects on body health remain unclear. Here, we investigated the effects of arecoline on physiologic and biochemical parameters in mouse serum, liver, brain, and intestine. The effect of arecoline on gut microbiota was investigated based on shotgun metagenomic sequencing. The results showed that arecoline promoted lipid metabolism in mice, manifested as significantly reduced serum TC and TG and liver TC levels and a reduction in abdominal fat accumulation. Arecoline intake significantly modulated the neurotransmitters 5-HT and NE levels in the brain. Notably, arecoline intervention significantly increased serum IL-6 and LPS levels, leading to inflammation in the body. High-dose arecoline significantly reduced liver GSH levels and increased MDA levels, which led to oxidative stress in the liver. Arecoline intake promoted the release of intestinal IL-6 and IL-1β, causing intestinal injury. In addition, we observed a significant response of gut microbiota to arecoline intake, reflecting significant changes in diversity and function of the gut microbes. Further mechanistic exploration suggested that arecoline intake can regulate gut microbes and ultimately affect the host's health. This study provided technical help for the pharmacochemical application and toxicity control of arecoline.

Chemical Composition, Pharmacological, and Toxicological Effects of Betel Nut

Betel nut, the fruit of Areca catechu L, has a long medical history in Southeast Asia. It is native to Malaysia and is cultivated and processed extensively in subtropical regions, such as South China and India. Betel nut almost appears as a "snack" in various occasions in most parts of China. Clinically, betel nut can play a certain pharmacology role and was used in malaria, ascariasis, arthritis, enterozoic abdominalgia, stagnation of food, diarrhea, edema, and beriberi. The nervous excitement of betel nut chewing has made it gradually become popular. However, chewing betel nut can induce oral submucosal fibrosis (OSF) and oral cancer (OC). At the same time, long-term chewing of betel nut also causes inhaled asthma, sperm reducing, betel quid dependence (BQD), and uterine and esophageal cancers. The main components of processed betel nut are the goal of this review. This study will mainly start from the pharmacological activity and toxicology study of betel nut in recent years, aiming to seek its advantages and disadvantages. In the meantime, this study will analyze and emphasize that betel nut and arecoline are the high-risk factors for oral cancer, which should arouse attention and vigilance of the public.

Evaluation of molecular markers GSTM1 and GSTT1 and clinical factors in breast cancer: case-control study and literature review

The study was conducted to evaluate the frequency of polymorphisms in GSTM1 and GSTT1 genes in patients with breast cancer compared with individuals without history of cancer, and the association of these polymorphisms with clinical/epidemiological parameters.There were evaluated 752 women (219 patients and 533 controls). Molecular analysis was performed by the Polymerase Chain Reaction (PCR). Statistical analysis was used multiple logistic regression and descriptive statistics.Age ≥50 years (OR =3.22, 95% CI =2.30 - 4.51, p <0.001) and alcohol consumption (OR =1.60, 95% CI =1.13 - 2.27, p = 0.008) were associated to the development of breast cancer, while smoking and null genotypes GSTM1 and GSTT1 presented no association. GSTM1 and GSTT1 polymorphisms presented no relationship with the clinical and histopathological parameters or molecular subtypes of breast cancer. Ninety-two percent of tumors were invasive ductal, 66% were grade II, 65% were larger than 2 cm, the stages II (35.3%) and III (31.2%) were the most prevalent, and 47.7% were molecular subtype luminal B.Individuals aged ≥50 years and alcohol consumers have more chance to developing breast cancer. GSTM1 and GSTT1 polymorphisms are not associated to the risk of breast cancer.

A Multicentre Observational Study on Risk Factors for Breast Cancer

Background

Breast cancer is the most common malignancy in Indian women. There is scant data from Indian hospital-based populations on the prevalence of risk factors of this disease. We performed this study to quantify and analyze various epidemiological risk factors in Indian breast cancer patients.

Methods

This was a multicenter collaborative study wherein breast cancer patients older than 18 years were served a structured questionnaire after informed consent. Patients or their relatives were required to fill out the questionnaire and those who were unable to read and write were excluded. Data were abstracted from case record forms and variables were descriptively analyzed.

Results

Between January 2015 and February 2016, 800 patients were screened, of whom 736 patients with a mean age of 50.13 years were enrolled in the study. The mean number of pregnancies was 2.75 (0-11), the number (percentage) of women who had breastfed for more than 6 months was 628 (85.3) and 406 (55.1%) patients were post-menopausal at the time of breast cancer diagnosis. Of the enrolled patients, 91 (12.8%) had history of exposure to passive smoke, 13 (1.8%) had partners who were heavy smokers, 27 (3.7%) had history of oral contraceptive use, 4 (0.5%) had history of hormone replacement therapy, and 103 (14%) had undergone hysterectomy with oophorectomy.

Conclusion

Our study contributes to the descriptive prevalence of some known risk factors in Indian breast cancer patients.

A meta-analysis and in silico analysis of polymorphic variants conferring breast cancer risk in the Indian subcontinent

Background: Genetic association studies on breast cancer on the Indian subcontinent have yielded conflicting results, and the precise effect of these variants on breast cancer pathogenesis is not known. Methods: Genomic variants, as obtained from selected studies from the Indian subcontinent, were subjected to random-effects and fixed-effect meta-analysis. Functional annotation of the relevant variants was done through a tried and tested in silico pipeline. Results: We found rs4646903/CYP1A1, rs1799814/CYP1A1, rs61886492/GCPII, del2/GSTM1, rs4680/COMT and rs1801394/MTRR to be associated with breast cancer. The del2/GSTM1 holds the association in premenopausal women. Conclusions: This is the first study of its kind from the Indian subcontinent analysing the extent of association of variants across populations followed by their functional annotation in the disease pathway.

Betel Nut Use in Vanuatu: Investigating Opportunities to Reduce Harms to Health

Background: Betel nut chewing is a public health concern in the Asia-Pacific region and is an emerging issue in Vanuatu. Despite the significant health risks associated with betel nut chewing, few interventions have been undertaken to reduce its harm. Objectives: To investigate betel nut use in Vanuatu and to identify opportunities to reduce its harm and possible interventions, framing the responses using the World Health Organization's MPOWER tobacco control model. Method: Qualitative research design, in the form of semi-structured interviews with ten participants with expertise in health, agriculture, education or non-communicable disease in Port Vila, Vanuatu during June 2017. Recorded interviews were transcribed verbatim, and a general inductive approach was used to identify key themes. Results: Participants reported a recent increase in betel nut use in Vanuatu due to the influence from Papua New Guinea and the Solomon Islands. To reduce the harm of betel nut use in Vanuatu, participants suggested policies and strategies that aligned with the MPOWER framework that could be adopted for betel nut control, including restricting cultivation and sale of betel nut in Vanuatu and using radio and existing community networks to reach people with messages about the dangers of betel nut use. Conclusion: Betel nut use may be growing in popularity in Vanuatu, where there are potential policy options to minimize harm. The MPOWER model for tobacco control may be a useful framework to help the Vanuatu government to deliver a comprehensive approach to reducing harm from betel nut use.

Investigating Betel Nut Use, Antecedents and Consequences: A Review of Literature

Background: Betel nut use is a public health issue in the Asia-Pacific region that is often neglected. To control betel nut use, understanding of the adverse effects of betel nut use and evidence-based policies and strategies is necessary. Objectives: This narrative review aims to characterize the current situation on betel nut use at a global level regarding the epidemiology, pharmacology and toxicology, health effects, treatment options, policies and strategies. Methods: We found 139 existing literature published between 1970-2019 on the Web of Science database and other technical documents to collate the most relevant information on betel nut use. Data were categorized into appropriate themes. Results: The literature demonstrates that there is a lack of up to date statistics on betel nut use. There is limited research on the effect of policies and strategies to control betel nut use. Conclusion: Betel nut-chewing countries should focus on understanding which populations chew betel nut and implement appropriate policies, educational and cessation programs to help control betel nut use.

Glutathione S-Transferase P1 313 (A > G) Ile105Val Polymorphism Contributes to Cancer Susceptibility in Indian Population: A Meta-analysis of 39 Case-Control Studies

GSTP1 involved in the metabolism of carcinogens and toxins, reduces damage of DNA and act as a suppressor of carcinogenesis. Many studies have reported that 313 A > G polymorphism is associated with different cancer in Indian population, but the results remain conflicting rather than conclusive. Therefore, we have performed meta-analysis to clarify the more precise association of GSPT1 313 A > G polymorphism with cancer risk in Indian population. We retrieved all relevant published literature from PubMed (Medline) and Google scholar web database and included those study only based on the established inclusion criteria. Pooled ORs and 95% CIs were used to appraise the strength of association. Publication bias and sensitivity analysis was also evaluated. A total of 6581 confirmed cancer cases and 8218 controls were included from eligible thirty nine case-controls studies. Pooled analysis suggested that the variant genotypes significantly increased the risk of cancer in allele (G vs. A: OR 1.266, 95% CI 1.129-1.418, p = 0.001), heterozygous (AG vs. AA: OR 1.191, 95% CI 1.047-1.355, p = 0.008), homozygous (GG vs. AA: OR 1.811, 95% CI 1.428-2.297, p = 0.001), dominant (GG + AG vs. AA: OR 1.276, 95% CI 1.110-1.466, p = 0.001) and recessive (GG vs. AG + AA: OR 1.638, 95% CI 1.340-2.002, p = 0.001) genetic models. The stability of these observations was confirmed by a sensitivity analysis. Begger's funnel plot and Egger's test did not reveal any publication bias. This meta-analysis suggests that the GSTP1 313 A > G polymorphism may contribute to genetic susceptibility to cancer in Indian population. However, larger studies and randomized clinical trial will be required to elucidate the biological and molecular mechanism of GSTP1 gene in cancer.

DNA Repair Mechanism Gene, XRCC1A ( Arg194Trp) but not XRCC3 ( Thr241Met) Polymorphism Increased the Risk of Breast Cancer in Premenopausal Females: A Case-Control Study in Northeastern Region of India

X-ray repair cross complementary group gene is one of the most studied candidate gene involved in different types of cancers. Studies have shown that X-ray repair cross complementary genes are significantly associated with increased risk of breast cancer in females. Moreover, studies have revealed that X-ray repair cross complementary gene polymorphism significantly varies between and within different ethnic groups globally. The present case–control study was aimed to investigate the association of X-ray repair cross complementary 1A (Arg194Trp) and X-ray repair cross complementary 3 (Thr241Met) polymorphism with the risk of breast cancer in females from northeastern region of India. The present case–control study includes histopathologically confirmed and newly diagnosed 464 cases with breast cancer and 534 apparently healthy neighborhood community controls. Information on sociodemographic factors and putative risk factors were collected from each study participant by conducting face-to-face interviews. Genotyping of X-ray repair cross complementary 1A (Arg194Trp) and X-ray repair cross complementary 3 (Thr241Met) was carried out by polymerase chain reaction-restriction fragment length polymorphism. For statistical analysis, both univariate and multivariate logistic regression analyses were performed. We also performed stratified analysis to find out the association of X-ray repair cross complementary genes with the risk of breast cancer stratified based on menstrual status. This study revealed that tryptophan allele (R/W-W/W genotype) in X-ray repair cross complementary 1A (Arg194Trp) gene significantly increased the risk of breast cancer (adjusted odds ratio = 1.44, 95% confidence interval = 1.06-1.97, P < .05 for R/W-W/W genotype). Moreover, it was found that tryptophan allele (W/W genotype) at codon 194 of X-ray repair cross complementary 1A (Arg194Trp) gene significantly increased the risk of breast cancer in premenopausal females (crude odds ratio = 1.66, 95% confidence interval = 1.11-2.46, P < .05 for R/W-W/W genotype). The present study did not reveal any significant association of X-ray repair cross complementary 3 (Thr241Met) polymorphism with the risk of breast cancer. The present study has explored that X-ray repair cross complementary 1A (Arg194Trp) gene polymorphism is significantly associated with the increased risk of breast cancer in premenopausal females from northeastern region of India which may be beneficial for prognostic purposes.

Lifelong vegetarianism and breast cancer risk: a large multicentre case control study in India

BACKGROUND

The lower incidence of breast cancer in Asian populations where the intake of animal products is lower than that of Western populations has led some to suggest that a vegetarian diet might reduce breast cancer risk.

METHODS

Between 2011 and 2014 we conducted a multicentre hospital based case-control study in eight cancer centres in India. Eligible cases were women aged 30-70 years, with newly diagnosed invasive breast cancer (ICD10 C50). Controls were frequency matched to the cases by age and region of residence and chosen from the accompanying attendants of the patients with cancer or those patients in the general hospital without cancer. Information about dietary, lifestyle, reproductive and socio-demographic factors were collected using an interviewer administered structured questionnaire. Multivariate logistic regression models were used to estimate the odds ratio (OR) and 95% confidence intervals for the risk of breast cancer in relation to lifelong vegetarianism, adjusting for known risk factors for the disease.

RESULTS

The study included 2101 cases and 2255 controls. The mean age at recruitment was similar in cases (49.7 years (SE 9.7)) and controls (49.8 years (SE 9.1)). About a quarter of the population were lifelong vegetarians and the rates varied significantly by region. On multivariate analysis, with adjustment for known risk factors for the disease, the risk of breast cancer was not decreased in lifelong vegetarians (OR 1.09 (95% CI 0.93-1.29)).

CONCLUSIONS

Lifelong exposure to a vegetarian diet appears to have little, if any effect on the risk of breast cancer.

Smokeless tobacco-associated cancers: A systematic review and meta-analysis of Indian studies

The International Agency for Research on Cancer (IARC) has concluded that there is sufficient evidence in humans for the carcinogenicity of smokeless tobacco (SLT) for mouth, oesophagus and pancreas, based largely on Western studies. We wanted to confirm this by conducting a systematic review using Indian studies because India faces the biggest brunt of SLT-attributable health effects. A systematic search was conducted for published and unpublished studies. Two authors independently reviewed the studies and extracted data. Summary odds ratio (OR) for each cancer type was calculated using fixed and random effects model. The population attributable fraction (PAF) method was used to calculate the attributable burden of incident cases. A significant association was found for oral-5.55 (5.07, 6.07), pharyngeal-2.69 (2.28, 3.17), laryngeal-2.84 (2.18, 3.70), oesophageal-3.17 (2.76, 3.63) and stomach-1.26 (1.00, 1.60) cancers. But in random effects model, laryngeal-1.79 (0.70, 4.54) and stomach-1.31 (0.92, 1.87) cancers became non-significantly associated. Gender-wise analysis revealed that women had a higher risk (OR = 12.0 vs. 5.16) of oral but a lower risk (1.9 vs. 4.5) of oesophageal cancer compared with men. For oral cancer, studies that adjusted for smoking, alcohol and other factors reported a significantly lower OR compared with studies that adjusted for smoking only or smoking and alcohol only (3.9 vs. 8.4). The annual number of attributable cases was calculated as 49,192 (PAF = 60%) for mouth, 14,747 (51%) for pharynx, 11,825 (40%) for larynx, 14,780 (35%) for oesophagus and 3,101 (8%) for stomach.

Evaluation of Female Breast Cancer Risk Among the Betel Quid Chewer: A Bio-Statistical Assessment in Assam, India

BACKGROUND

Breast cancer is the most commonly diagnosed cancer among the female population of Assam, India. Chewing of betel quid with or without tobacco is common practice among female population of this region. Moreoverthe method of preparing the betel quid is different from other parts of the country.So matched case control study is conducted to analyse whetherbetel quid chewing plays a significant role in the high incidence of breast cancer occurrences in Assam.

METHODS AND MATERIAL

Here, controls are matched to the cases by age at diagnosis (±5 years), family income and place of residence with matching ratio 1:1. Conditional logistic regression models and odd ratios (OR) was used to draw conclusions.

RESULTS

It is observed that cases are more habituated to chewing habits than the controls.Further the conditional logistic regression analysis reveals that betel quid chewer faces 2.353 times more risk having breast cancer than the non-chewer with p value 0.0003 (95% CI 1.334-4.150).

CONCLUSION

Though the female population in Assam usually does not smoke, the addictive habits typical to this region have equal effect on the occurrence of breast cancer.

A meta-analysis of the association of glutathione S-transferase P1 gene polymorphism with the susceptibility of breast cancer

Glutathione S-transferase P1 (GSTP1) is one of the important mutant sites for the cancer risk at present. The conclusions of the published reports on the relationship between GSTP1 A/G gene polymorphism and the risk of breast cancer are still debated. This meta-analysis was performed to evaluate the association between GSTP1 and the risk of breast cancer. The association reports were identified from PubMed and Cochrane Library, and eligible studies were included and synthesized using meta-analysis method. 35 investigations were included into this meta-analysis for the association of GSTP1 A/G gene polymorphism and breast cancer susceptibility, consisting of 40,347 subjects (18,665 patients with breast cancer and 21,682 controls). The association between GSTP1 A/G gene polymorphism and breast cancer risk was not found for overall population, Caucasians and Africans. Interestingly, the GSTP1 A/G gene polymorphism was associated with the susceptibility of breast cancer in Asians (G allele: OR = 1.10, 95 % CI: 1.04-1.17, P = 0.001; GG genotype: OR = 1.36, 95 % CI: 1.14-1.62, P = 0.0008; AA genotype: OR = 0.92, 95 % CI: 0.85-0.98, P = 0.02). Furthermore, the GSTP1 A/G gene polymorphism was associated with the susceptibility of breast cancer for the analysis of the controls from hospital. In conclusion, GSTP1 A/G gene polymorphism is associated with the breast cancer susceptibility in Asians. However, more studies on the relationship between GSTP1 A/G gene polymorphism and the risk of breast cancer should be performed in further.

Polymorphisms of catechol estrogens metabolism pathway genes and breast cancer risk in Mexican women

Breast cancer is associated to estrogen exposure. Allelic variants involved in estrogen metabolism might change the risk of developing this neoplasia. We examined the potential association of breast cancer risk in Mexican women with the polymorphisms CYP1A1 rs1048943, CYP1B1 rs1056836, COMT rs4680, GSTP1 rs1695, GSTT1 null and GSTM1 null which are involved in estrogen metabolism pathway. This study included 150 cases and 150 controls. A significant association was observed between, CYP1A1 rs1048943 (OR = 1.95, C.I. 1.13-3.36) and GSTP1 rs1695 (OR = 2.39, C.I. 1.24-4.24) polymorphisms with the risk of breast cancer. This risk was increased when the women were stratified according to their menopausal status. The results show that breast cancer risk significantly increases in women with 3-6 risk polymorphisms (OR = 3.75, C.I. 1.44-9.74).

Genomic alterations in breast cancer patients in betel quid and non betel quid chewers

Betel Quid (BQ) chewing independently contributes to oral, hepatic and esophageal carcinomas. Strong association of breast cancer risk with BQ chewing in Northeast Indian population has been reported where this habit is prodigal. We investigated genomic alterations in breast cancer patients with and without BQ chewing exposure. Twenty six BQ chewers (BQC) and 17 non BQ chewer (NBQC) breast cancer patients from Northeast India were analyzed for genomic alterations and pathway networks using SNP array and IPA. BQC tumors showed significantly (P<0.01) higher total number of alterations, as compared with NBQC tumors, 48±17% versus 32±25 respectively. Incidence of gain in fragile sites in BQC tumors were significantly (P<0.001) higher as compared with NBQC tumors, 34 versus 23% respectively. Two chromosomal regions (7q33 and 21q22.13) were significantly (p<0.05) associated with BQC tumors while two regions (19p13.3–19p12 and 20q11.22) were significantly associated with NBQC tumors. GO terms oxidoreductase and aldo-keto reductase activity in BQC tumors in contrast to G-protein coupled receptor protein signaling pathway and cell surface receptor linked signal transduction in NBQC tumors were enriched in DAVID. One network “Drug Metabolism, Molecular Transport, Nucleic Acid Metabolism” including genes AKR1B1, AKR1B10, ETS2 etc in BQC and two networks “Molecular Transport, Nucleic Acid Metabolism, Small Molecule Biochemistry” and “Cellular Development, Embryonic Development, Organismal Development” including genes RPN2, EMR3, VAV1, NNAT and MUC16 etc were seen in NBQC. Common alterations (>30%) were seen in 27 regions. Three networks were significant in common regions with key roles of PTK2, RPN2, EMR3, VAV1, NNAT, MUC16, MYC and YWHAZ genes. These data show that breast cancer arising by environmental carcinogens exemplifies genetic alterations differing from those observed in the non exposed ones. A number of genetic changes are shared in both tumor groups considered as crucial in breast cancer progression.

Multiple analytical approaches reveal distinct gene-environment interactions in smokers and non smokers in lung cancer

Complex disease such as cancer results from interactions of multiple genetic and environmental factors. Studying these factors singularly cannot explain the underlying pathogenetic mechanism of the disease. Multi-analytical approach, including logistic regression (LR), classification and regression tree (CART) and multifactor dimensionality reduction (MDR), was applied in 188 lung cancer cases and 290 controls to explore high order interactions among xenobiotic metabolizing genes and environmental risk factors. Smoking was identified as the predominant risk factor by all three analytical approaches. Individually, CYP1A1*2A polymorphism was significantly associated with increased lung cancer risk (OR = 1.69;95%CI = 1.11–2.59,p = 0.01), whereas EPHX1 Tyr113His and SULT1A1 Arg213His conferred reduced risk (OR = 0.40;95%CI = 0.25–0.65,p<0.001 and OR = 0.51;95%CI = 0.33–0.78,p = 0.002 respectively). In smokers, EPHX1 Tyr113His and SULT1A1 Arg213His polymorphisms reduced the risk of lung cancer, whereas CYP1A1*2A, CYP1A1*2C and GSTP1 Ile105Val imparted increased risk in non-smokers only. While exploring non-linear interactions through CART analysis, smokers carrying the combination of EPHX1 113TC (Tyr/His), SULT1A1 213GG (Arg/Arg) or AA (His/His) and GSTM1 null genotypes showed the highest risk for lung cancer (OR = 3.73;95%CI = 1.33–10.55,p = 0.006), whereas combined effect of CYP1A1*2A 6235CC or TC, SULT1A1 213GG (Arg/Arg) and betel quid chewing showed maximum risk in non-smokers (OR = 2.93;95%CI = 1.15–7.51,p = 0.01). MDR analysis identified two distinct predictor models for the risk of lung cancer in smokers (tobacco chewing, EPHX1 Tyr113His, and SULT1A1 Arg213His) and non-smokers (CYP1A1*2A, GSTP1 Ile105Val and SULT1A1 Arg213His) with testing balance accuracy (TBA) of 0.6436 and 0.6677 respectively. Interaction entropy interpretations of MDR results showed non-additive interactions of tobacco chewing with SULT1A1 Arg213His and EPHX1 Tyr113His in smokers and SULT1A1 Arg213His with GSTP1 Ile105Val and CYP1A1*2C in nonsmokers. These results identified distinct gene-gene and gene environment interactions in smokers and non-smokers, which confirms the importance of multifactorial interaction in risk assessment of lung cancer.