Assessment of genetic damage among chewers of mixture containing mainly areca nut and tobacco

Plant leads for mitigation of oral submucous fibrosis: Current scenario and future prospect

The aim of this review is to enumerate medicinal plants and their bioactive compounds that may become potential leads in the mitigation of oral submucous fibrosis (OSMF) in the forthcoming future. It is focused on pathophysiology, risk factors, current treatment regimen, potential plant leads, and future therapies for OSMF. Data were extracted from a vast literature survey by using SciFinder, Web of Science, Google Scholar, and PubMed search engines with relevant keywords. Upon literature survey, we found that the phytochemical 'arecoline' present in the areca nut is the main causative agent of OSMF condition. Currently, OSMF is treated by immunomodulatory and anti-inflammatory agents such as corticosteroids, enzymes (hyaluronidase, chymotrypsin, and collagenase), anti-inflammatory mediators (isoxsuprine and pentoxifylline), dietary supplements (vitamins, antioxidants, and micronutrients), and anti-fibrotic cytokines like interferon-gamma that provides short-term symptomatic relief to OSMF patients. However, some plant leads have been proven effective in alleviating symptoms and mitigating OSMF, which ultimately improves the quality of OSMF patients' life. We concluded that plant drugs like lycopene, curcumin, Aloe vera, colchicine, and Glycyrrhiza glabra are effective against OSMF in various in vitro and/or clinical studies and are being used by modern and traditional practitioners.

Association of genetic polymorphism of glutathione S-transferases with colorectal cancer susceptibility in snuff (Naswar) addicts

Abstract The current study aimed to investigate the relationship between polymorphisms in detoxifying (GSTM1, GSTT1, and GSTP1) genes and their association with colorectal cancer (CRC) in tobacco addicts of Pashtun ethnicity. Polymorphisms in the selected genes were genotyped in a case-control study consisting of 100 histologically confirmed male CRC patients and 100 birth-year and gender-matched healthy controls using the PCR−RFLP method. The GSTM1 null, and GSTT1 null genotypes were significantly contributed to the risk of CRC in the cases (OR= 3.131, 95% CI: 1.451−6.758, P = 0.004, and OR= 3.541, 95% CI: 1.716−7.306, P = 0.001, respectively), whereas the association observed for GSTP1 Val/Val (1.139, 95% CI: 0.356−3.644, P = 0.826) did not show statistical significance. The combined GSTM1 null and GSTT1 null showed a 41-fold increased risk (95% CI: 4.945−351.950, P = 0.001), while, the combined GSTM1 null and GSTP1 Ile/Val or Val/Val variant genotypes exhibited about 3-fold (95% CI: 1.196−7.414, P = 0.019) increased risk to CRC. Similarly, the combined GSTT1 null and GSTP1 Ile/Val or Val/Val variant genotypes showed about a 3-fold (95% CI: 1.285−8.101, P = 0.013) increased risk of CRC. In the combination of three GST genotypes, the GSTM1 null, GSTT1 null, and GSTP1 Ile/Val or Val/Val variant genotypes demonstrated a more than a 22-fold (95% CI: 2.441−212.106, P = 0.006) increased risk of CRC. Our findings suggest that GSTM1 and GSTT1 polymorphism and its combination with GSTP1 may be associated with CRC susceptibility in the Naswar addicted Pashtun population of Khyber Pakhtunkhwa, Pakistan.

Comet assay as a suitable biomarker for in vivo oral carcinogenesis: a systematic review

BACKGROUND AND OBJECTIVES

In order to detect genetic damage, different methods have been developed, such as micronuclei and comet assay. The comet assay presents some advantages when compared to the other aforementioned methods, including wide versatility, as any eukaryotic cell can be evaluated at an individual cellular level. In this context, the aim of this systematic review was designed to help further elucidate the following question: is the comet assay a suitable biomarker of in vivo oral carcinogenesis?

MATERIAL AND METHODS

The present systematic review was performed in accordance with the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) guidelines. Full manuscripts from 18 studies were carefully selected in this setting.

RESULTS

A total of 15 studies demonstrated positive findings for genotoxicity in peripheral blood or oral cells in patients with pre-malignant lesions or oral cancer. In the quality assessment of studies, 1 was classified as Strong, 5 were considered as Moderate, and 12 were classified as Weak.

CONCLUSION

In summary, the comet assay can be a useful biomarker for oral carcinogenesis. However, further studies with more strict parameters are suggested (with less uncontrolled confounders) in order to increase findings reliability for diagnosis of oral potentially malignant lesions.

Areca nut and smokeless tobacco exposure induces micronucleus, other nuclear abnormalities and cytotoxicity in early chick embryo

Areca nut (AN) and smokeless tobacco (SLT) are indiscriminately consumed among the populations of Southeast and South Asian countries, even by women during the gestational period. This study aimed to investigate the genotoxic and cytotoxic potentials of AN and Sadagura (SG), a unique homemade SLT preparation, alone and in combination in early chick embryos. Fertile white leghorn chicken eggs were randomly divided into five treatment groups: vehicle control, positive control (Mitomycin C, 20 μg/egg), AN, SG, and AN+SG. AN, SG, and AN+SG were given at dosages of 0.125, 0.25, and 0.5 mg/egg. The hen's egg test for micronucleus induction (HET-MN) was performed in chick embryos to evaluate the genotoxic potential of the test agents. Furthermore, the cytotoxic potential was assessed by studying erythroblast cell populations and the polychromatic erythrocytes (PCEs) to normochromatic erythrocytes (NCEs) ratio. Our results indicated a significant increase (p < .001) in MN frequency and other nuclear abnormalities, suggesting the potential of AN and SG to cause genotoxicity. Also, AN and SG exposure alone and in combination considerably altered the erythroblast cell population (%) and the PCE to NCE ratio in all the treatment periods. Our findings established the genotoxic and cytotoxic potential of both AN and SG alone and in combination during early embryonic development in the chick embryo.

Correlation between smokeless tobacco (Gutkha) and biomarkers of oxidative stress in plasma with cardiovascular effects

Tobacco products are widely consumed around the world in smoking and smokeless tobacco (SLT) forms. Analysis of smokeless tobacco consumption suggested that the effects of nicotine and tobacco-specific N-nitrosamines, the main ingredients of smokeless tobacco are attractive to study because its consumption often results in biochemical changes of plasma parameters and markers of oxidative stress development. Smokeless tobacco users generally consume the most commonly available SLT products like khaleja brand of gutkha and mahak chaini brand of khaini 3–5 times per day. We found a significant increase in plasma glucose levels, total cholesterol, triglycerides, and a significant decrease in high-density lipoprotein (HDL) cholesterol indicative of atherosclerosis risk. We also found that the plasma peroxynitrites (ONOO⁻), nitric oxide (NO), lipid peroxidation (LPO), and protein carbonyls (PCO) levels were significantly elevated. Plasma nicotine and cotinine levels were significantly elevated in study subjects, suggesting that nicotine could be responsible for the oxidative and nitrosative stress indirectly inducing cardiovascular risk. There was a strong correlation of nicotine with reactive oxygen species (ROS), reactive nitrogen species (RNS), cholesterol, and creatinine in exposed smokeless tobacco (gutkha) consumers. These data demonstrate SLT users are at high cardiovascular risk due to nicotine-induced free radicals and oxidative damage.

Key Drivers to Implement an Evidence-based Tobacco Control Programme in Schools of India: A Mixed-Methods Study

Background:

Adolescence is an influential stage in students’ lives when lifelong behaviours such as tobacco use are formed. During these years, school teachers are important role models for tobacco control among students. A study was conducted among school personnel and administrators to understand the key drivers for implementing an evidence-based school tobacco control program.

Methodology:

A cross-sectional, mixed-method study was conducted in five districts of Assam, India. The quantitative study was conducted among 565 school personnel across 40 Government-aided schools. Data was collected by means of an anonymous, self-administered questionnaire. Qualitative data was generated from 15 focus group discussions (FGDs) among 146 participants - District Program Officers, Block Education Officers, Cluster Coordinators, Headmasters and Teachers.

Results:

While the prevalence of smoked tobacco was low (3%), the use of smokeless tobacco was higher (40%), and the prevalence of use of areca nut without tobacco (65%) was still higher among school personnel. They were aware of the school policies prohibiting the use of tobacco among students within or outside school buildings or during school-sponsored activities (81%); they had rather limited knowledge about policy for themselves (58%). There was lack of access to training materials about prevention of tobacco use among youth. The FGDs amongst school personnel resulted in several constructive suggestions on tobacco control in schools mainly in training school teachers, monitoring the program and incentives for execution of the program. However, there was a reluctance to implement a smokeless tobacco control programme since many were current users of smokeless tobacco and areca nut.

Conclusion:

Tobacco control policies as well as training school personnel in schools need to improve and further measures must be taken to prohibit use of areca nut, which contains carcinogens. The existing system of the education department can be utilised to implement tobacco control programmes effectively.

Smokeless Tobacco Use in Iran: A Systematic Review

Background

Smokeless tobacco (ST) use is one of the most important public health problems in Southeast Asia. The use of these substances increases the incidence of some cancers and other diseases. The purpose of this review study was to investigate on ST use in Iran.

Methods

A literature search was conducted on PubMed, Google Scholar, and three national databases [Scientific Information Database (SID), IranMedex, and IranDoc] based on the standard search strategy.

Findings

Most consumer people lived in Sistan and Baluchestan Province (Zahedan and Chabahar Cities) and Golestan Province, Iran. ST use rates ranged from 11.0% to 45.7% among college students in Sistan and Baluchestan (Zahedan and Chabahar) and Golestan. There are various types of ST consumed in Iran that have been mentioned in various articles, including Pan, Gutka, Nass, Naswar, Biti, and Supari.

Conclusion

Most studies on ST have been conducted in Sistan and Baluchestan and Golestan Provinces and we need more research for other provinces. Consumption by women is a warning and a threat to women's health in the future. Further studies will be needed to find out more precisely the prevalence of consumption in Iran.

Multifaceted Mechanisms of Areca Nuts in Oral Carcinogenesis: the Molecular Pathology from Precancerous Condition to Malignant Transformation

Oral cancer is one of the most frequent malignant diseases worldwide, and areca nut is a primary carcinogen causing this cancer in Southeast Asia. It has been widely reported that areca nut induced several cytotoxic effects in oral cells, including ROS generation, inflammation, tissue hypoxia, DNA damage, and cell invasion. Recently, through chronic exposure model, more extensive pathological effects due to areca nut have been found. These include the induction of autophagy, promotion of epithelial- mesenchymal transition, and facilitation of cancer stemness conversion. Clinical findings support these adverse effects. Oral submucosal fibrosis, a premalignant condition, is prevalent in the area with habitual chewing of areca nuts. Consistently, oral cancer patients with habitual chewing areca nut exhibit more aggressive phenotypes, including resistance to chemo-radiotherapy. In this review, we comprehensively discuss and concisely summarize the up-to-date molecular and cellular mechanisms by which areca nuts contribute to malignant transformation. This review may provide critical information regarding clinical applications in risk assessment, disease prevention, diagnosis, and personalized therapeutics for areca nut-induced oral malignancy.

Malignant transformation of oral submucous fibrosis: overview of histopathological aspects

Oral submucous fibrosis (OSF), first described in 1952, is a potentially malignant disorder associated with betel quid and areca nut chewing, mostly prevalent in the population of the Indian subcontinent and South East Asia. Malignant transformation of OSF to squamous cell carcinoma (SCC) has been estimated to be between 2% and 8%. Our study aimed to review the histopathologic changes that contribute to the understanding of the malignant transformation of OSF. Changes in epithelial thickness and dysplasia characterized by micronuclei, altered AgNOR counts and distribution, keratin protein alteration, and alteration of P63 and E-cadherin characterize the epithelial changes during the transformation of OSF to SCC. Common mechanisms have been proposed to be involved in OSF and SCC, through collagen maturation and their interaction with myofibroblasts and mast cells. Fibrosis-driven vascular constriction that results in epithelial hypoxia has also been proposed as an important mechanism for the malignant transformation of OSF. However, reassessment of the classical view is required, because with demonstration of large blood vasculature in the connective tissue stroma of OSF, the hypothesis associated with tissue hypoxia-induced malignant transformation of OSF can be questioned.

Betel quid chewing without tobacco: a meta-analysis of carcinogenic and precarcinogenic effects

Betel quid without tobacco is an important factor influencing the incidences of oral cancer and precancer. This study systematically evaluated the associations between betel quid containing no tobacco and oral cancer and precancer, with implications for the prevention of oral cancer. We searched MEDLINE, ISI Web of Science, and EMBASE (to April 2011) and retrieved studies that investigated the relationship between chewing betel quid and oral cancer (or precancer). We performed a meta-analysis to summarize the published data and describe the prevalence of betel quid use with regard to cancerous diseases. In all, 19 eligible studies that reported odds ratios and 95% confidence intervals for oral cancer with respect to betel quid were included. The analysis identified an association suggesting that betel quid might be an important risk factor for oral cancer and precancer. The results of this review suggest that betel-chewing-cessation programs should be developed to help prevent oral diseases.

Tobacco and areca nut chewing--reproductive impairments: an overview

A large number of people are using smokeless tobacco and areca nut worldwide. Sufficient data on tobacco smoking have harmful effect on human health and reproduction is available. However, data on the smokeless tobacco and areca nut use on human reproduction is scanty. This overview is an attempt to compose on the consumption of smokeless tobacco and areca nut on human reproduction and some relevant experimental data were also included. The existing studies suggest that tobacco and areca nut chewing alone, together or with other ingredients had reproductive toxic potential. Pregnant women using smokeless tobacco during pregnancy also had adverse effect on pregnancy and its outcome. Thus pregnant women must avoid consumption of any mixture containing areca nut and tobacco in order to protect the pregnancy and outcome. The data suggest that smokeless tobacco use is also harmful as smoking for reproduction and use of areca nut might have further compounded the problem.

Association of betel nut with carcinogenesis: revisit with a clinical perspective

Betel nut (BN), betel quid (BQ) and products derived from them are widely used as a socially endorsed masticatory product. The addictive nature of BN/BQ has resulted in its widespread usage making it the fourth most abused substance by humans. Progressively, several additives, including chewing tobacco, got added to simple BN preparations. This addictive practice has been shown to have strong etiological correlation with human susceptibility to cancer, particularly oral and oropharyngeal cancers.

The PUBMED database was searched to retrieve all relevant published studies in English on BN and BQ, and its association with oral and oropharyngeal cancers. Only complete studies directly dealing with BN/BQ induced carcinogenesis using statistically valid and acceptable sample size were analyzed. Additional relevant information available from other sources was also considered.

This systematic review attempts to put in perspective the consequences of this widespread habit of BN/BQ mastication, practiced by approximately 10% of the world population, on oral cancer with a clinical perspective. BN/BQ mastication seems to be significantly associated with susceptibility to oral and oropharyngeal cancers. Addition of tobacco to BN has been found to only marginally increase the cancer risk. Despite the widespread usage of BN/BQ and its strong association with human susceptibility to cancer, no serious strategy seems to exist to control this habit. The review, therefore, also looks at various preventive efforts being made by governments and highlights the multifaceted intervention strategies required to mitigate and/or control the habit of BN/BQ mastication.

Why Do Bangladeshi People Use Smokeless Tobacco Products?

Despite scientific evidence about the harmful effects of smokeless tobacco (SLT), it is widely used in Bangladesh. This study explored perceptions about health effects of SLT use. Semistructured interviews were conducted with 1812 nonsmoking adults. About 40% of the participants were current SLT users or had used SLT in the past. Family members’ influence was the main factor for initiation. The participants believed that people continued using SLT because of addiction (52%) and as a part of their lifestyle (23%). The majority of participants (77%) did not mention any benefit, but SLT users considered it to be a remedy for toothache ( P < .05). Almost all participants mentioned that SLT was harmful and causes heart disease, cancer, and tuberculosis. Doctors’ advice was the common motivating factor to quit. Health promotion interventions should highlight the adverse effects of SLT use, which outweigh the perceived benefits, and should consider addressing the role of family in SLT initiation and use.