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

Molecular pathways and targeted therapies in head and neck cancers pathogenesis

The substantial heterogeneity exhibited by head and neck cancer (HNC), encompassing diverse cellular origins, anatomical locations, and etiological contributors, combined with the prevalent late-stage diagnosis, poses significant challenges for clinical management. Genomic sequencing endeavors have revealed extensive alterations in key signaling pathways that regulate cellular proliferation and survival. Initiatives to engineer therapies targeting these dysregulated pathways are underway, with several candidate molecules progressing to clinical evaluation phases, including FDA approval for agents like the EGFR-targeting monoclonal antibody cetuximab for K-RAS wild-type, EGFR-mutant HNSCC treatment. Non-coding RNAs (ncRNAs), owing to their enhanced stability in biological fluids and their important roles in intracellular and intercellular signaling within HNC contexts, are now recognized as potent biomarkers for disease management, catalyzing further refined diagnostic and therapeutic strategies, edging closer to the personalized medicine desideratum. Enhanced comprehension of the genomic and immunological landscapes characteristic of HNC is anticipated to facilitate a more rigorous assessment of targeted therapies benefits and limitations, optimize their clinical deployment, and foster innovative advancements in treatment approaches. This review presents an update on the molecular mechanisms and mutational spectrum of HNC driving the oncogenesis of head and neck malignancies and explores their implications for advancing diagnostic methodologies and precision therapeutics.

Health effects associated with chewing tobacco: a Burden of Proof study

Chewing tobacco use poses serious health risks; yet it has not received as much attention as other tobacco-related products. This study synthesizes existing evidence regarding the health impacts of chewing tobacco while accounting for various sources of uncertainty. We conducted a systematic review and meta-analysis of chewing tobacco and seven health outcomes, drawing on 103 studies published from 1970 to 2023. We use a Burden of Proof meta-analysis to generate conservative risk estimates and find weak-to-moderate evidence that tobacco chewers have an increased risk of stroke, lip and oral cavity cancer, esophageal cancer, nasopharynx cancer, other pharynx cancer, and laryngeal cancer. We additionally find insufficient evidence of an association between chewing tobacco and ischemic heart disease. Our findings highlight a need for policy makers, researchers, and communities at risk to devote greater attention to chewing tobacco by both advancing tobacco control efforts and investing in strengthening the existing evidence base.

Duration and frequency of betel quid chewing affects periodontitis severity and life quality of people in Tanini Village, Kupang, Indonesia

BACKGROUND

Chewing betel nuts can increase the risk of periodontal disease severity and potentially become malignant in the oral cavity.

OBJECTIVE

This study aimed to investigate the effect of the duration and frequency of betel quid chewing behaviour on periodontitis severity and the life quality of people in Tanini Village, Kupang Regency, Indonesia.

METHODS

The type of this study was an analytic observational study with a cross-sectional design. We used a questionnaire to obtain sociodemographic data. Oral Health Survey Basic Methods were used to measure debris index, plaque index, bleeding on probing, loss of attachment, and pocket depth. Behaviour and quality of life were measured by questionnaire and WHOQOL-BREF method as well.

RESULTS

The largest number of respondents were male. Duration of chewing had a significant relationship with the frequency of chewing and periodontal status. Periodontitis was higher compared to all categories. The lifestyle of the community greatly influenced their behaviour in betel nut chewing and also affected the severity of their periodontitis and OHIs significantly.

CONCLUSION

The lifestyle of betel nut chewing of the people in Tanini Village, greatly influences their behaviour. Prolonged and excessive use of betel nut induced significant adverse effects on human health. The longer and more often chew betel or areca nut, the higher the incidence of periodontitis, which significantly affects the quality of life as there is a possibility of the development of carcinogenesis, particularly in the oral cavity.

Unveiling Mysteries of Quid-Induced Lichenoid Reactions: A Cross-Sectional Study

Lichenoid reactions occur exclusively in people who chew tobacco, areca nut, or both, in raw or any manufactured or processed form. The lesion is described as a lichen-planus-like lesion and is termed as quid-induced lichenoid reaction (QILR). In this cross-sectional study, amongst 935 quid consumers, 82 patients were diagnosed with QILR and it was seen that 65 patients used processed forms of tobacco and areca nut. Thereby, it could be concluded that QILR might occur because of flavors used in processing of tobacco and areca nut.

Prognosis of South Asian Buccal Mucosa Cancer Patients in the United States: Association of Race with Overall Survival

BACKGROUND

Squamous Cell Carcinoma (SCC) of the buccal mucosa and gingiva accounts for approximately 10% of oral and pharyngeal cancers diagnosed in the United States each year, with a disproportionally higher incidence in individuals of South Asian descent. However, little has been documented regarding trends pertaining to overall survival. Thus, this research serves to identify predictors of survival and determine if overall survival (OS) differs for South Asians compared to other races once they develop non-metastatic buccal mucosa or gingiva squamous cell carcinoma.

METHODS

A population-based, cohort study of patients registered in the National Cancer Database® (NCDB) between the years 2004-2016 was performed. Kaplan-Meyer Survival Curves were executed to examine overall survival, while univariable (UVA) and multivariable analysis (MVA) was performed to determine the effect of multiple variables on OS.

RESULTS

South Asians had longer median OS at 88.7 months, compared to 58.6 months and 38.3 months for Caucasians and African Americans respectively (p<0.001). In UVA, race was highly significant, but when the cohort was selected to include only those who had undergone surgical resection, no statistically significant difference remained. On MVA, lack of surgery, older age, higher grade, higher T and N stage, use of chemotherapy, higher comorbidity scores were associated with worse OS, but race was not significant.

CONCLUSION

South Asians in the US with non-metastatic buccal mucosa or gingiva SCC have better OS compared to Caucasians or African Americans, likely due to younger age at diagnosis (median 59 vs. 71 and 62 years old) and more frequent surgical resection (75% vs. 72% and 64%). In MVA, South Asians have similar OS as Caucasians.

Chemical Composition of Areca Nut and Its Adverse Effects on Human Health

Areca nut (AN) is one of the addictive substances consumed widely in the world. The composition of AN is very complex, and each component has variable properties. This study aims to review the composition of AN and its adverse effects on humans. For this review, the literature search was performed by an electronic search of the Pubmed/Medline, Scopus, and Google Scholar databases using proper MESH headings and retrieved the articles published from 1997 to 2022. The eligibility criteria included human studies, a form of AN, the composition of AN, harmful effects of AN, the effect of AN on the oral cavity, the effect of AN on vital organs, and articles published in English. Data were extracted regarding the composition of AN, forms of AN, and harmful effects of AN on the oral cavity and on other systems. A total of 449 articles were identified from various databases, and 36 studies were selected that met the inclusion criteria. The active components of AN, which produce harmful effects, are primarily alkaloids, polyphenols, tannins, and certain trace elements. AN is consumed in different forms, and based on the form, its composition also varies. AN is known to cause deleterious effects on the oral cavity as well as various body organs. The most dangerous and widely reported impacts of AN on the oral cavity are the development of oral submucous fibrosis, a premalignant condition, and oral malignancy. However, during the chewing process, excretory products of AN are released and circulate in the body of "chronic habitual" and affect the other body parts. Thus, AN consumption may contribute to cardiac, liver, endocrinal, metabolic, respiratory, and reproductive system disorders also. AN composition is complex, and its consumption is harmful to human health. In regard to controlling the issue of the harmful effects of this habit, preventive measures should be established.

Evaluating Alterations of the Oral Microbiome and Its Link to Oral Cancer among Betel Quid Chewers: Prospecting Reversal through Probiotic Intervention

Areca nut and slaked lime, with or without tobacco wrapped in Piper betle leaf, prepared as betel quid, is extensively consumed as a masticatory product in many countries across the world. Betel Quid can promote the malignant transformation of oral lesions as well as trigger benign cellular and molecular changes. In the oral cavity, it causes changes at the compositional level in oral microbiota called dysbiosis. This dysbiosis may play an important role in Oral Cancer in betel quid chewers. The abnormal presence and increase of bacteria Fusobacterium nucleatum, Capnocytophaga gingivalis, Prevotella melaninogenica, Peptostreptococcus sp., Porphyromonas gingivalis, and Streptococcus mitis in saliva and/or other oral sites of the cancer patients has attracted frequent attention for its association with oral cancer development. In the present review, the authors have analysed the literature reports to revisit the oncogenic potential of betel quid and oral microbiome alterations, evaluating the potential of oral microbiota both as a driver and biomarker of oral cancer. The authors have also shared a perspective that the restoration of local microbiota can become a potentially therapeutic or prophylactic strategy for the delay or reversal of lip and oral cavity cancers, especially in high-risk population groups.

Low-dose arecoline regulates distinct core signaling pathways in oral submucous fibrosis and oral squamous cell carcinoma

BACKGROUND

Betel nut chewing plays a role in the pathogenesis of oral submucous fibrosis (OSF) and oral squamous cell carcinoma (OSCC). As the major active ingredient of the betel nut, the effect of arecoline and its underlying mechanism to OSF and OSCC pathogenesis remain unclear.

METHODS

Next-generation sequencing-based transcriptome and dRRBS analysis were performed on OSF and OSCC cells under low-dose arecoline exposure. Functional analyses were performed to compare the different roles of arecoline during OSF and OSCC pathogenesis, and key genes were identified.

RESULTS

In this study, we identified that low-dose arecoline promoted cell proliferation of both NFs and OSCC cells via the acceleration of cell cycle progression, while high-dose arecoline was cytotoxic to both NFs and OSCC cells. We performed for the first time the transcriptome and methylome landscapes of NFs and OSCC cells under low-dose arecoline exposure. We found distinct transcriptome and methylome profiles mediated by low-dose arecoline in OSF and OSCC cells, as well as specific genes and signaling pathways associated with metabolic disorders induced by low-dose arecoline exposure. Additionally, low-dose arecoline displayed different functions at different stages, participating in the modulation of the extracellular matrix via Wnt signaling in NFs and epigenetic regulation in OSCC cells. After exposure to low-dose arecoline, the node roles of FMOD in NFs and histone gene clusters in OSCC cells were found. Meanwhile, some key methylated genes induced by arecoline were also identified, like PTPRM and FOXD3 in NFs, SALL3 and IRF8 in OSCC cells, indicating early molecular events mediated by arecoline during OSF and OSCC pathogenesis.

CONCLUSIONS

This study elucidated the contribution of low-dose arecoline to OSF and OSCC pathogenesis and identified key molecular events that could be targeted for further functional studies and their potential as biomarkers.

Molecular Signature of Long Non-Coding RNA Associated with Areca Nut-Induced Head and Neck Cancer

The areca nut is a high-risk carcinogen for head and neck cancer (HNC) patients in Southeast Asia. The underlying molecular mechanism of areca nut-induced HNC remains unclear, especially regarding the role of long non-coding RNA (lncRNA). This study employed a systemic strategy to identify lncRNA signatures related to areca nut-induced HNC. In total, 84 cancer-related lncRNAs were identified. Using a PCR array method, 28 lncRNAs were identified as being dysregulated in HNC cells treated with areca nut (17 upregulated and 11 downregulated). Using bioinformatics analysis of The Cancer Genome Atlas Head-Neck Squamous Cell Carcinoma (TCGA-HNSC) dataset, 45 lncRNAs were differentially expressed in tumor tissues from HNC patients (39 over- and 6 under-expressions). The integrated evaluation showed 10 lncRNAs dysregulated by the areca nut and altered expression in patients, suggesting that these panel molecules participate in areca nut-induced HNC. Five oncogenic (LUCAT1, MIR31HG, UCA1, HIF1A-AS2, and SUMO1P3) and tumor-suppressive (LINC00312) lncRNAs were independently validated, and three key molecules were further examined. Pathway prediction revealed that LUCAT1, UCA1, and MIR31HG modulate multiple oncogenic mechanisms, including stress response and cellular motility. Clinical assessment showed that these lncRNAs exhibited biomarker potentials in diagnosis (area under the curve = 0.815 for LUCAT1) and a worse prognosis (both p < 0.05, survival analysis). Cellular studies further demonstrated that MIR31HG facilitates areca nut-induced cancer progression, as silencing this molecule attenuated arecoline-induced invasion ability in HNC cells. This study identified lncRNA signatures that play a role in areca nut-induced HNC. These molecules may be further applied in risk assessment, diagnosis, prognosis, and therapeutics for areca nut-associated malignancies.

Prevalence, Habit Pattern, and Awareness on Harmful Effects of Tobacco/Areca Nut Use among Patients Visiting a Tertiary Care Center in Sri Lanka

Background The carcinogenicity of tobacco and areca nut is well established worldwide. Areca nut is the fourth most common psychoactive substance identified recently. The effects of areca nut on the autonomic nervous system make the users dependent on the habit which has been an emerging health issue among Sri Lankan adults and adolescents. This study aimed to evaluate the prevalence and patterns of these risk habits among the patients attending a tertiary care center in Sri Lanka, and their awareness of the harmful effects of the habit.

Method A hospital-based cross-sectional study was conducted among 512 patients using an interviewer-administered questionnaire.

Results The sample consisted of 167 (33%) tobacco consumers. The average age of the initiation of tobacco consumption was 23.66 years (standard deviation ± 8.04). Age (p = 0.001), gender (p = 0.001), income (p = 0.005), and educational level (p = 0.001) are significantly associated with tobacco consumption. There is a strong likelihood for tobacco consumers to consume areca nut (odds ratio [OR] 30.58, 95% confidence interval [CI] 17.05–54.88) and alcohol (OR 11.16, 95% CI 6.91–17.98) at any stage in their lives. The majority of the tobacco consumers (61%) were smokeless tobacco users. Areca nut consumers are 0.44 times more likely to know its carcinogenic effects than nonconsumers (95% CI 0.28–0.69). Tobacco consumers are more likely to be aware of the harmful effects of tobacco consumption than nonconsumers (OR 1.11, 95% CI 0.45–2.74). Sixty percent have made at least one attempt to quit the habit. Sixty-two percent of the unsuccessful quitters reported the reason as “addiction.”

Conclusion Prevalence of smokeless tobacco consumption prevails at a high level among Sri Lankans. Tobacco and areca nut users are more likely to be aware of its harmful effects than the nonconsumers but unable to quit the habit due to the psychoactive properties of tobacco and areca nut.

Carcinogenic Effects of Areca Nut and Its Metabolites: A Review of the Experimental Evidence

Oral cancers (OC) are among the most frequent malignancies encountered in Southeast Asia, primarily due to the prevalent habit of betel quid (BQ) and smokeless tobacco use in this region. Areca nut (AN), the primary ingredient in BQ, contains several alkaloids, including arecoline, arecaidine, guvacoline, and guvacine. These have been associated with both the AN abuse liability and carcinogenicity. Additionally, variations in AN alkaloid levels could lead to differences in the addictiveness and carcinogenic potential across various AN-containing products. Recent studies based on animal models and in vitro experiments show cellular and molecular effects induced by AN. These comprise promoting epithelial-mesenchymal transition, autophagy initiation, tissue hypoxia, genotoxicity, cytotoxicity, and cell death. Further, clinical research endorses these undesired harmful effects in humans. Oral submucosal fibrosis, a potentially malignant disease of the oral cavity, is predominantly reported from the geographical areas of the globe where AN is habitually chewed. OC in chronic AN users presents a more aggressive phenotype, such as resistance to anti-cancer drugs. The available evidence on the carcinogenicity of AN based on the findings reported in the recently published experimental studies is discussed in the present review.

Metabolism of the areca alkaloids - toxic and psychoactive constituents of the areca (betel) nut

Areca nut (AN) is consumed by millions of people for its therapeutic and psychoactive effects, making it one of the most widely self-administered psychoactive substances in the world. Even so, AN use/abuse is associated with myriad oral and systemic side effects, affecting most organ systems in the body. Alkaloids abundant in the nut (e.g. arecoline, arecaidine, guvacoline, and guvacine), collectively called the areca alkaloids, are presumably responsible for the major pharmacological effects experienced by users, with arecoline being the most abundant alkaloid with notable toxicological properties. However, the mechanisms of arecoline and other areca alkaloid elimination in humans remain poorly documented. Therefore, the purpose of this review is to provide an in-depth review of areca alkaloid pharmacokinetics (PK) in biological systems, and discuss mechanisms of metabolism by presenting information found in the literature. Also, the toxicological relevance of the known and purported metabolic steps will be reviewed. In brief, several areca alkaloids contain a labile methyl ester group and are susceptible to hydrolysis, although the human esterase responsible remains presumptive. Other notable mechanisms include N-oxidation, glutathionylation, nitrosamine conversion, and carbon-carbon double-bond reduction. These metabolic conversions result in toxic and sometimes less-toxic derivatives. Arecoline and arecaidine undergo extensive metabolism while far less is known about guvacine and guvacoline. Metabolism information may help predict drug interactions with human pharmaceuticals with overlapping elimination pathways. Altogether, this review provides a first-of-its-kind comprehensive analysis of AN alkaloid metabolism, adds perspective on new mechanisms of metabolism, and highlights the need for future metabolism work in the field.

Role of TNFSF15 variants in oral cancer development and clinicopathologic characteristics

Tumour necrosis family superfamily (TNFSF) member 15 (TNFSF15), encoded by TNFSF15, regulates immune responses and inflammation. However, the roles of TNFSF15 single‐nucleotide variants (SNVs; formerly SNPs) in oral cavity squamous cell carcinoma (OCSCC) remain unclear. This case–control study included 2523 participants (1324 patients with OCSCC [52.5%] and 1199 healthy controls [47.5%]). The effects of TNFSF15 rs3810936, rs6478108 and rs6478109 on cancer development and prognosis were analysed by real‐time PCR genotype assay. The Genotype‐Tissue Expression (GTEx) and The Cancer Genome Atlas (TCGA) databases were used to validate our findings. The results demonstrated that the patients with altered TNFSF15 SNVs had poorer histological differentiation than did those with wild‐type alleles. TNFSF15 SNVs were significantly associated with moderate‐to‐poor histological differentiation in univariate logistic regression. In the GTEx database, the expression of altered TNFSF15 SNVs in whole blood was lower than that of wild‐type alleles. However, the expression of altered SNVs in the upper aerodigestive mucosa was higher than that of wild‐type alleles. In the TCGA database, the patients with higher TNFSF15 expression had shorter overall survival than did those with lower TNFSF15 expression, especially for human papillomavirus‐negative and advanced staging groups. In conclusion, although TNFSF15 SNVs did not affect OCSCC development, the patients with altered TNFSF15 SNVs exhibited poorer histological differentiation. The patients with higher TNFSF15 expression had poorer prognosis than did those with lower TNFSF15 expression.

Oral Cancer Disparities in the Outer US-affiliated Pacific Islands

OBJECTIVE/HYPOTHESIS

Oral cancers in the US-affiliated Pacific Islands are poorly described despite disproportionately higher incidences in certain jurisdictions. This study attempts to better characterize the incidence, staging, and management of oral cancers in this region.

STUDY DESIGN

Retrospective Epidemiological Study.

METHODS

A retrospective review was conducted across the US-affiliated Pacific Islands between 2007 and 2019. Patient data were obtained for individuals with primary head and neck cancers from the Pacific Regional Central Cancer Registry database. All cohorts were age-adjusted to the 2000 US Standard Population. Further analysis was performed on oral cavity cancers due to their clear predominance within the sample.

RESULTS

A total of 585 patients with primary head and neck cancers were included. The average age was 54.5 ± 12.9 years, and most patients were male (76.8%). Oral cancer subsite analysis revealed the proportional incidence of buccal mucosa was higher in 5 of 9 jurisdictions when compared with the United States (p < 0.001). Tongue and lip cancers were not found to have significantly higher incidence proportions. Patients in the Pacific Islander group were less likely to be detected at earlier stages for cancers of the cheek and other mouth (p < 0.001), tongue (p < 0.001), and lips (p < 0.001) compared with the United States.

CONCLUSIONS

Many Pacific Island populations are burdened with higher incidences of oral cancer with later staging. Further investigation is recommended to evaluate oral cancer-related outcomes and mortality in this region.

LEVEL OF EVIDENCE

3 Laryngoscope, 2022.

Validation of a high-throughput method for simultaneous determination of areca nut and tobacco biomarkers in hair using microwave-assisted extraction and isotope dilution liquid chromatography tandem mass spectrometry

For people with habits of chewing betel nuts and smoking, the probability of suffering from oral cancer is ten to a hundred times higher than others. Due to the serious health consequences of areca nut and tobacco, a reliable cessation program is needed. Hair is the best option to document long-term exposure. Unfortunately, the research on betel nut in hair did not attract much attention. In this study, a high-throughput method based on microwave-assisted extraction (MAE) and isotope dilution liquid chromatography tandem mass spectrometry (LC-MS/MS) was developed to measure the four biomarkers of betel nuts and cigarettes, including areca alkaloids (arecoline), tobacco alkaloids (nicotine), and their metabolites (arecaidine and cotinine). The hair sample was washed, cut, weighed, and incubated for 3 min MAE with methanol/trifluoroacetic acid, then evaporated and reconstituted for LC-MS/MS analysis. The total experiment time was 50 min. The lower limits of quantification (LOQ) were 5-10 pg/mg. The intra-day and inter-day precision were 2.2-7.6%. Intra-day and inter-day accuracy were - 6.1-8.2%. The method showed good linearity (r2 > 0.995) over LOQ - 1000 pg/mg concentration ranges. It was successfully applied to analyze 11 subjects of regular areca nut chewers, also smokers. Eight samples were black hair; three samples were naturally black hair with partially gray hair. Measured concentrations in black hair were in the range 56.9 pg/mg to 3.2 ng/mg for arecoline, 12.8 pg/mg to 222.2 pg/mg for arecaidine, 3.8 ng/mg to 33.4 ng/mg for nicotine and 1.1 ng/mg to 6.1 ng/mg for cotinine. The results showed lower levels in gray hair. This method was utilized successfully to analyze pg/mg levels of arecoline, arecaidine, nicotine, and cotinine, and good recoveries were obtained. The mean concentration of arecaidine and cotinine in hair was 15% and 20% of arecoline and nicotine, respectively. A good positive correlation was found between the concentrations of these compounds and self-report. This method improved extraction speed, concentration, and analysis of samples and is useful for monitoring betel nut and smoking cessation programs.

The World of Oral Cancer and Its Risk Factors Viewed from the Aspect of MicroRNA Expression Patterns

Oral cancer is one of the leading causes of death worldwide, with a reported 5-year survival rate of around 50% after treatment. Epigenetic modifications are considered to have a key role in oral carcinogenesis due to histone modifications, aberrant DNA methylation, and altered expression of miRNAs. MicroRNAs (miRNAs) are small non-coding RNAs that have a key role in cancer development by regulating signaling pathways involved in carcinogenesis. MiRNA deregulation identified in oral cancer has led to the idea of using them as potential biomarkers for early diagnosis, prognosis, and the development of novel therapeutic strategies. In recent years, a key role has been observed for risk factors in preventing and treating this malignancy. The purpose of this review is to summarize the recent knowledge about the altered mechanisms of oral cancer due to risk factors and the role of miRNAs in these mechanisms.

Simultaneous determination of areca nut- and tobacco-specific alkaloids in saliva by LC-MS/MS: Distribution and transformation of alkaloids in oral cavity

Areca nut and tobacco are frequently used in combination. Cigarette smoking and betel quid (BQ) chewing habits impose greater oral cancer risk than either habit alone. Saliva is a better noninvasive diagnostic material as it is in direct contact with oral mucosa and cancerous lesions. This study describes the application of isotope-dilution LC-MS/MS for simultaneous quantitation of five areca nut-specific alkaloids (ASAs) and three tobacco-specific alkaloids (TSAs) in human saliva. With this method, we demonstrate that the distribution of ASAs vary significantly in smokers who chew BQ habitually, due to the hydrolysis of ASAs and metabolic activity in the oral cavity. The alkaline condition formed due to slaked lime in BQ, plays an important role in the distribution of ASAs and TSAs, by catalyzing the hydrolysis of ester forms of ASAs to their respective carboxylic acid forms besides facilitating the TSA (i.e., nicotine) absorption in the oral cavity. Moreover, our results reveal that oral mucosa rather than saliva contributes to the metabolism of ASAs at oral cavity. Less than 2.1% of ASAs were metabolized by saliva, as determined by in vitro test. Our findings may provide a better insight into the pathobiology of oral carcinogenesis due to BQ chewing.

Evaluation of the inhalation toxicity of arecoline benzoate aerosol in rats

Arecoline is a pharmacologically active alkaloid isolated from Areca catechu. There are no published data available regarding the inhalation toxicity of arecoline in animals. This study aimed to evaluate the inhalation toxicity of arecoline in vitro and in vivo. For this purpose, arecoline benzoate (ABA) salt was prepared to stabilize arecoline in an aerosol. The MTT assay determined the half-maximal inhibitory concentration values of ABA and arecoline in A549 cell proliferation to be 832 μg/ml and 412 μg/ml, respectively. The toxicity of acute and subacute inhalation in Sprague-Dawley rats was evaluated using the guidelines of the Organization for Economic Cooperation and Development. For acute inhalation, the median lethal concentration value of ABA solvent was >5175 mg/m³ . After the exposure and during the recovery period, no treatment-related clinical signs were observed. In the 28-Day inhalation toxicity test, daily nose-only exposure to 2510 mg/m³ aerosol of the ABA solvent contained 75 mg/m³ ABA for male rats and 375 mg/m³ ABA for female rats, which caused no observed adverse effects, except for the decreased body weight gain in male rats exposed to 375 mg/m³ ABA. In this study, the no observed adverse effect level (NOAEL) for the 28-Day repeated dose inhalation of ABA aerosol was calculated to be around 13 mg/kg/day for male rats and 68.8 mg/kg/day for female rats, respectively.

Molecular Mechanisms of Malignant Transformation of Oral Submucous Fibrosis by Different Betel Quid Constituents-Does Fibroblast Senescence Play a Role?

Betel quid (BQ) is a package of mixed constituents that is chewed by more than 600 million people worldwide, particularly in Asia. The formulation of BQ depends on a variety of factors but typically includes areca nut, betel leaf, and slaked lime and may or may not contain tobacco. BQ chewing is strongly associated with the development of potentially malignant and malignant diseases of the mouth such as oral submucous fibrosis (OSMF) and oral squamous cell carcinoma (OSCC), respectively. We have shown recently that the constituents of BQ vary geographically and that the capacity to induce disease reflects the distinct chemical composition of the BQ. In this review, we examined the diverse chemical constituents of BQ and their putative role in oral carcinogenesis. Four major areca alkaloids—arecoline, arecaidine, guvacoline and guvacine—together with the polyphenols, were identified as being potentially involved in oral carcinogenesis. Further, we propose that fibroblast senescence, which is induced by certain BQ components, may be a key driver of tumour progression in OSMF and OSCC. Our study emphasizes that the characterization of the detrimental or protective effects of specific BQ ingredients may facilitate the development of targeted BQ formulations to prevent and/or treat potentially malignant oral disorders and oral cancer in BQ users.

New Scenarios in Pharmacological Treatments of Head and Neck Squamous Cell Carcinomas

Head and neck squamous cell carcinoma (HNSCC) is one of the most frequent types of cancer with a lethal outcome in half of the diagnosed cases. Mostly, HNSCC develops in the oral cavity, and its development is associated with tobacco and areca nut/betel quid usage, alcohol consumption, and HPV infection. Oral squamous cell carcinoma, as other head and neck cancers, presents a high degree of intratumor heterogeneity, which makes their treatment difficult, and directly correlates with drug resistance. Since the classical treatments for HNSCC oftentimes do not resolve the clinical picture, there is great need for novel therapeutic approaches, models for drug testing, and new drug delivery systems.

A contemporary narrative review to guide molecular epidemiology of oral submucous fibrosis

Oral submucous Fibrosis (OSMF) is a chronic disease that mainly affects the upper part of the aerodigestive tract. Areca nut and betel quid chewing has been established as the most significant causative factor for this condition. While OSMF is a predominantly Asian disease, the migrant populations from the region have taken the disease across the globe. Additionally, areca nut is now easily accessible in flavors and aggressively marketed. Many research activities have been undertaken for decades to understand the etiopathogenesis and risk factors of OSMF. Although OSMF is a slowly progressing disease, it has the potential to transform to an oral malignancy. This article is an attempt to review the literature and provide an update on its prevalence, etiopthogenesis and its diagnosis. We also highlight certain clinical, histopathological and molecular features that aid in the diagnosis and prognostication of OSMF, highlighting the importance of identifying the possibly high risk OSMF that is prone to malignant transformation. Using this information, future directions can be developed to include treatmentof OSMF through a dynamic gene-specific approach.

Genome skims analysis of betel palms (Areca spp., Arecaceae) and development of a profiling method to assess their plastome diversity

The betel nut (Areca catechu L., Arecaceae) is a monoecious cultivated palm tree that is widespread in tropical regions. It is mainly cultivated for producing areca nuts, from which seeds are extracted and chewed by local populations principally in the Indo-Pacific region. Seeds contain alkaloids which are central nervous system stimulants and are highly addictive. Wild relatives of the betel nut are distributed in South Asia and Australasia, with ca. 40-50 Areca species currently recognized. The geographic origin(s) of the betel nut and its subsequent diffusion and diversification remains poorly documented. Here, a genome skimming approach was applied to screen nucleotidic variation in the most abundant genomic regions. Low coverage sequencing data allowed us to assemble full plastomes, mitochondrial regions (either full mitogenomes or the full set of mitochondrial genes) and the nuclear ribosomal DNA cluster for nine representatives of the Areca genus collected in the field and herbarium collections (including a 182-years old specimen collected during the Dumont d'Urville's expedition). These three genomic compartments provided similar phylogenetic signals, and revealed very low genomic diversity in our sample of cultivated betel nut. We finally developed a genotyping method targeting 34 plastid DNA microsatellites. This plastome profiling approach is useful for tracing the spread of matrilineages, and in combination with nuclear genomic data, can resolve the history of the betel nut. Our method also proves to be efficient for analyzing herbarium specimens, even those collected >100 years ago.

Areca Nut Chewing: Initiation, Addiction, and Harmful Effects Emphasizing the Barriers and Importance of Cessation

Areca nut is a highly addictive substance with carcinogenic properties and causes many harmful effects to the human body. Alkaloids are the major chemicals found in areca nut, and their mechanism of action has been studied for several years. About 600 million people around the world use areca nut, and its usage is higher in Asian countries. Areca nut chewers get used to the habit mainly due to social influence, stress, or lack of awareness. Some studies have reported a dependence syndrome related to areca nut chewing. Even though there are many ongoing research studies regarding tobacco addiction, less concern has been given to the areca nut addiction. There are only few studies related to areca nut cessation, and even those few cessation programs are mainly designed using tobacco cessation methodology. Sociocultural influence, behavioral factors, and accessibility are the main barriers to cessation. Behavior changing interventions proved to be more effective in areca nut cessation, but recently studies on pharmacological therapies are also emerging.

Factors influencing transmission of tuberculosis in Ngeu Nata culture among Ngada community in Kupang, East Nusa Tenggara, Indonesia: Cross sectional study

Background

Eating “sirih/Betel” (Ngeu Nata) as a culture in Ngada society can become one of the primary source of Tuberculosis (TB) transmission due to share leaves and betel liquid reservoirs together with other people. If one of the people who share leaves is a TB patient, it can transmit TB to other person. The purpose of this study was to identify the factors that influence TB transmission in Ngeu Nata culture using the health belief model approach.

Design and Methods

This study used cross-sectional, involving 110 respondents, selected by consecutive sampling. The respondents were Bajawa ethnicity, age 36-67, at least consume Betel one a day together with other person in Ngada district, East Nusa Tenggara.

Results

The results showed that most respondents had high transmission behavior in betel eating culture (51.8%). Factors related to TB transmission behavior: medical history of TB (p=0.028), knowledge about TB (p=0.038), the perceived of severity of TB (p=0.037); the perceived of benefits (p=0.039) and the perceived of barrier (p=0.038). The dominant factor was knowledge, (OR 2,365 (95% CI) 1,015-5,510).

Conclusions

Implication: nurses should include aspect of Ngeu Nata cultural in designing TB education for Bajawa ethnicity in order to prevent TB transmission in Ngada district, East Nusa Tenggara.

Habit-associated salivary pH changes in oral submucous fibrosis: A cross-sectional study

Background:

Salivary pH plays a significant role in the pathogenesis of various oral diseases and conditions. Chewing of areca nut and various tobacco products changes salivary pH.

Aim:

The aim of the study was to measure the effect of habitual chewing of areca nut and various tobacco products on salivary pH.

Materials and Methods:

The present study included 360 individuals (chewers and nonchewers) of age group between 20 and 30 years who visited the Outpatient Department of Hi-Tech Dental College and Hospital. The patient's salivary pH was measured with the help of a digital pH meter before and after chewing areca nut and various tobacco products.

Results:

It was observed that, in all the groups of chewers, pH decreased after chewing except in the gutkha and lime chewing group, where pH increased (pH before chewing was 7.43 ± 0.41 and after chewing was 7.51 ± 0.399), the difference was strongly significant (P < 0.001). pH was found to be less in lime and tobacco chewers (6.83 ± 0.33) and more in tobacco, betel nut, and lime chewers (7.50 ± 0.41) in comparison to other groups before chewing; the difference was strongly significant (P < 0.001). In the mean ± standard deviation, increase in pH was found among chewers (7.32 ± 0.49) as compared to nonchewers (6.99 ± 0.14), which is the control group, and the data were statically significant (P < 0.001).

Conclusion:

pH is altered in areca nut and various tobacco chewers, rendering the oral mucosa vulnerable to the toxic effects of areca nut and various tobacco products.

A Positive Relationship between Betel Nut Chewing and Significant Liver Fibrosis in NAFLD Subjects, but Not in Non-NAFLD Ones

Background: Betel nut chewing is associated with oral cancer, cardiovascular disease, liver cirrhosis, and hepatocellular carcinoma (HCC). The aim of this study was to explore the association of betel nut chewing with liver fibrosis in subjects with and without nonalcoholic fatty liver disease (NAFLD). Method: A total of 5967 subjects were enrolled. NAFLD was diagnosed with ultrasonography. Betel nut chewing was classified into non-chewing, ex-chewing, and current chewing, and cumulative dosages were calculated. The aspartate aminotransferase (AST)/platelet ratio index and NAFLD fibrosis scores (NFS) were calculated for evaluation of liver fibrosis. Results: NAFLD increased the associated risk of liver fibrosis in those with (odds ratio (OR): 5.51, 95% confidence interval (CI): 3.09–9.80) and without betel nut chewing (OR: 2.33, 95% CI: 1.64–3.29). In subjects without NAFLD, betel nut chewing was not associated with liver fibrosis (OR: 1.12, 95% CI: 0.44–2.86). In subjects with NAFLD, cumulative betel nut chewing and ex- and current chewing were positively associated with NFS and significant liver fibrosis. Conclusions: In subjects with NAFLD, betel nut chewing, even ex-chewing, was associated with a higher risk of liver fibrosis, where higher cumulative levels were found to increase the risk of significant liver fibrosis. However, the associated risk of liver fibrosis due to betel nut chewing was insignificant in subjects without NAFLD.

Comparing the Incidence of Buccal Mucosa Cancer in South Asian, White, and Black Populations Residing in the United States: A Cross-Sectional Analysis

Background:

Recreational use of the betel nut, which is common among the South Asian population, is a known risk factor for developing Head and Neck cancer. As South Asians comprise a significant proportion of the United States population, we seek to determine if those living within the country experience a higher rate of head and neck cancers compared to other races.

Methods:

Data of patients diagnosed with head & neck cancers from 2010-2016 was collected from the National Cancer Database^® and compared to race-matched US census data for each corresponding year to calculate incidence. Pairwise comparisons were performed between the incidence for South Asians versus Whites and South Asians versus Blacks using one sided Chi-square tests.

Results:

South Asians experienced a significantly higher incidence of buccal mucosa/vestibule cancers when compared to Whites or Blacks for every year between 2010-2016, but a comparatively lower incidence of larynx or oropharynx cancers.

Conclusions:

South Asians residing within the United States have a higher incidence of buccal mucosa/vestibule cancers, but a lower incidence of more common cancers, such as larynx or oropharynx cancer. This may suggest that the etiology behind the high buccal mucosa/vestibule cancer incidence is due to a social habit, as opposed to an inherent racial susceptibility.

Micronuclei and upper body cancers (head, neck, breast cancers) a systematic review and meta-analysis

A systematic review and a meta-analysis were performed on 19 studies on head and neck cancer (HNC) and 21 studies on breast cancer (BC) to evaluate the application of micronucleus (MN) assay as a predictive and prognostic test for cancer risk. In these studies the MN test was applied in peripheral lymphocytes and buccal cells of patients and healthy subjects with family history of cancer. The meta-analysis on MN applied in buccal cells of HNC patients was performed on two subgroups of studies. A significant increase of MN frequency in patients compared to healthy controls was observed for the subgroup on oral cancer (243 cases/370 controls, meta-MR = 4.71 95 %CI:2.75-8.06) and HNC (204 patients/163 controls metaMR=2.28 95 %CI:2.02-2.58). A metaMR = 3.27 (95 %CI:1.41-7.59) was obtained for MN applied in peripheral lymphocytes on HNC (160 cases/160 controls). For BC, the analysis of MN in peripheral lymphocytes showed significantly higher values in patients (n = 761) than in controls (n = 788) (meta-MR1.90 95 % CI:1.44-2.49). No statistically significant increase of baseline MN was detected in studies on groups of healthy subjects with BC family history (n = 224) or with BRCA1/2 mutations (n = 101) with respect to the controls. After ex-vivo challenge with ionizing radiation, the meta-analysis revealed a slightly statistically significant increase in MN only in BC patients (n = 614) compared to controls (n = 622)(meta-MR = 1.11 95 %CI:1.02-1.21); no increase was observed in healthy subjects with BC family history carrying or not BRCA1/2 mutations. Significant difference between BC patients (n = 183) and controls (n = 165) was observed by the meta-analysis of data on MN in buccal cells (MR = 3.89 95 %CI:1.54-9.78). The MN assay in buccal cells has some perspective of clinical application in HNC.

Vildagliptin, a dipeptidyl peptidase-4 inhibitor, reduces betel-nut induced carcinogenesis in female mice

AIM

Betel-nut, a popular masticatory among Southeast Asian populations is a class I carcinogen, previously associated with dyslipidemia and aberrant lipid metabolism, and is reported to be used more frequently by females, than males. This study investigates the potential of repurposing the anti-diabetic drug, vildagliptin, a dipeptidyl peptidase-4 inhibitor, for alleviating the oncogenic condition in female Swiss Albino mice administered an aqueous extract of betel-nut (AEBN) orally (2 mg ml^-1) for 24 weeks.

MAIN METHODS

Tissues were investigated by histopathological, immunohistochemical and apoptosis assays. Biochemical analyses of oxidative stress markers and lipid profile were performed using different tissues and sera. The expressions of different proteins involved in lipid metabolism and oncogenic pathways were evaluated by Western blotting.

KEY FINDINGS

AEBN induced carcinogenesis primarily in the liver by significantly impairing AMPK signaling, inducing oxidative stress, activating Akt/mTOR signaling, increasing Ki-67 immunoreactivity and cyclin D1 expression, and significantly diminishing apoptosis. Co-administration of AEBN with vildagliptin (10 mg kg^-1 body weight) for 8 weeks reduced liver dysplasia, and significantly decreased free palmitic acid, increased free oleic acid, normalized lipid profile, decreased oxidative stress, cyclin D1 expression, Ki-67 immunoreactivity, and Bcl2 expression, and increased the ratio of apoptotic/non-apoptotic cells. Mechanistically, vildagliptin elicited these physiological and molecular alterations by restoring normal AMPK signaling and reducing the cellular expressions of FASN and HMGCR, restoring AMPK-dependent phosphorylation of p53 at Ser-15 and reducing Akt/mTOR signaling.

SIGNIFICANCE

These results indicate that vildagliptin may alleviate betel-nut induced carcinogenesis in the liver of female mice.

Is F-18 FDG PET/computed tomography a useful tool to restage the patients with tongue carcinoma?

OBJECTIVE

The aim of this study was to evaluate the diagnostic performance of contrast-enhanced F-18 fluoro-2-deoxyglucose (F-18 FDG) PET/computed tomography (CT) in restaging of tongue carcinoma.

MATERIAL AND METHODS

Retrospectively analysis of carcinoma tongue patients (n = 110) who were treated and referred for FDG PET/CT. Histopathological examination and clinical or imaging follow-up were taken as gold standard.

RESULTS

Of 110 patients, FDG PET/CT detected FDG avid lesions in 69 (62.7%) patients. Sensitivity, specificity and diagnostic accuracy of FDG PET/CT were 92.9%, 90.0% and 91.8%, respectively, for residual/recurrence disease detection (P < 0.05). Additionally, in six patients, metachronous primaries were also detected [lung (4), esophagus and lymphoma (1) each]. The mean maximum standardized uptake value (SUVmax) with 95% confidence interval for primary site recurrence, regional lymph nodes and metastatic lesions was 11.51 (9.53-13.48), 69 (62.7%) (7.88-11.48) and 8.94 (3.11-14.76), respectively.

CONCLUSION

FDG PET/CT demonstrates high diagnostic accuracy for detection of residual/recurrent disease in treated tongue cancer patients and PET/CT should be considered as first-line diagnostic investigation in these patients.

Genetic toxicology and toxicokinetics of arecoline and related areca nut compounds: an updated review

Areca nut (AN) is consumed by more than 600 million of individuals, particularly in some regions of South Asia, East Africa, and tropical Pacific, being classified as carcinogenic to humans. The most popular way of exposure consists of chewing a mixture of AN with betel leaf, slaked lime, and other ingredients that may also contain tobacco named betel quid (BQ). Arecoline is the principal active compound of AN, and, therefore, has been systematically studied over the years in several in vitro and in vivo genotoxicity endpoints. However, much of this information is dispersed, justifying the interest of an updated and comprehensive review article on this topic. In this sense, it is thus pertinent to describe and integrate the genetic toxicology data available as well as to address key toxicokinetics aspects of arecoline. This review also provides information on the effects induced by arecoline metabolites and related compounds, including other major AN alkaloids and nitrosation derivatives. The complexity of the chemicals involved renders this issue a challenge in genetic toxicology. Overall, positive results in several endpoints have been reported, some of them suggesting a key role for arecoline metabolites. Nevertheless, some negative genotoxicity findings for this alkaloid in short-term assays have also been reported in the literature. Finally, this article also collates information on the potential mechanisms of arecoline-induced genotoxicity, and suggests further approaches to tackle this important toxicological issue.

Downregulation of the DNA Repair Gene DDB2 by Arecoline Is through p53's DNA-Binding Domain and Is Correlated with Poor Outcome of Head and Neck Cancer Patients with Betel Quid Consumption

Arecoline is the principal alkaloid in the areca nut, a component of betel quids (BQs), which are carcinogenic to humans. Epidemiological studies indicate that BQ-chewing contributes to the occurrence of head and neck cancer (HNC). Previously, we have reported that arecoline (0.3 mM) is able to inhibit DNA repair in a p53-dependent pathway, but the underlying mechanism is unclear. Here we demonstrated that arecoline suppressed the expression of DDB2, which is transcriptionally regulated by p53 and is required for nucleotide excision repair (NER). Ectopic expression of DDB2 restored NER activity in arecoline-treated cells, suggesting that DDB2 downregulation was critical for arecoline-mediated NER inhibition. Mechanistically, arecoline inhibited p53-induced DDB2 promoter activity through the DNA-binding but not the transactivation domain of p53. Both NER and DDB2 promoter activities declined in the chronic arecoline-exposed cells, which were consistent with the downregulated DDB2 mRNA in BQ-associated HNC specimens, but not in those of The Cancer Genome Atlas (TCGA) cohort (no BQ exposure). Lower DDB2 mRNA expression was correlated with a poor outcome in HNC patients. These data uncover one of mechanisms underlying arecoline-mediated carcinogenicity through inhibiting p53-regulated DDB2 expression and DNA repair.

Topical medicines for wound healing: A systematic review of Unani literature with recent advances

ETHNOPHARMACOLOGICAL RELEVANCE

Wound healing is an important area of research in contemporary medicine. Unani is a traditional medicine system based on hundreds of years of observations and experiences. Wounds are described under the headings qarha (arabic) and jarāhat (persian) in classical Unani texts. Several drugs of herbal, mineral and animal origin are described in Unani texts as having wound healing properties. Many of these drugs have been screened on various scientific parameters but the potential of most drugs remains unexplored.

METHODOLOGY

The study was aimed at summarizing the topical wound healing drugs mentioned in classical Unani books. The topical wound healing drugs were first identified in classical texts. Then 20 drugs were selected for detailed review on the basis of clinical relevance and wide availability.

OBSERVATIONS AND RESULTS

Seventy drugs were identified in Unani texts after removal of duplicacy. Most of the drugs (85.71%) were of herbal origin, while 10% were of mineral origin and the rest 4.28% were of animal origin. Most of the herbal drugs belonged to the Fabaceae (10%) and Rosaceae (8.33%) families. Biologically active compounds such as phenols, sterols, hydrocarbons, anthocyanidins, flavonoids and tannins have been identified in almost all drugs which support classical literature.

CONCLUSION

Unani system of medicine has a rich legacy of effective wound healing drugs, which is reinforced by modern researches. Most drugs exert their action on multiple phases of wound healing. In addition, most drugs have no reported adverse effects in laboratory and clinical studies. Hence, Unani medicine may offer the much-needed affordable and effective wound care in a wide range of clinical settings.

Cotargeting CHK1 and PI3K Synergistically Suppresses Tumor Growth of Oral Cavity Squamous Cell Carcinoma in Patient-Derived Xenografts

Oral cavity squamous cell carcinomas (OSCCs) are aggressive tumors, and their recurrence leads to poor prognosis and reduced survival rates. This study aimed to identify therapeutic targets and to evaluate the efficacy of targeted inhibitors in OSCC patient-derived xenograft (PDX) models. Herein, we reported that OSCC PDXs recapitulated the genomic signatures of their paired primary tumors and the expression of CHEK1, PIK3CA, and PIK3CD was significantly upregulated in OSCC. The antitumor efficacy of CHK1 inhibitors (PF477736, AZD7762, LY2606368) and PI3K inhibitors (BYL719, GDC0941, GSK1059615) was investigated in OSCC cell lines and PDX models. Targeting either CHK1 or PI3K effectively inhibited cell proliferation and colony formation by inducing cell cycle arrest and apoptosis in in vitro cell-based assays. Cisplatin-based chemotherapy combined with CHK1 inhibitor treatment synergistically inhibited cell proliferation by suppressing CHK1 phosphorylation and inducing PARP cleavage. Furthermore, compared with monotherapy, cotreatment with CHK1 and PI3K inhibitors exerted synergistic anticancer effects by suppressing CHK1, AKT, and 4E-BP1 phosphorylation. In summary, our study identified CHK1 and PI3K as promising targets, especially in a dual treatment strategy combining a CHK1 inhibitor with cisplatin or a PI3K inhibitor as a novel therapeutic approach for OSCC patients with aberrant cell cycle regulation and PI3K signaling activation.

Glutathione S-transferasesP1 AA (105Ile) allele increases oral cancer risk, interacts strongly with c-Jun Kinase and weakly detoxifies areca-nut metabolites

The Glutathione S-transferases (GSTs) protects cellular DNA against oxidative damage. The role of GSTP1 polymorphism (A313G; Ile105Val) as a susceptibility factor in oral cancer was evaluated in a hospital-based case-control study in North-East India, because the habit of chewing raw areca-nut (RAN) with/without tobacco is common in this region. Genetic polymorphism was investigated by genotyping 445 cases and 444 controls. Individuals with the GSTP1 AA-genotype showed association with the oral cancer (OR = 3.1, 95% CI = 2.4–4.2, p = 0.0002). Even after adjusting for age, sex and habit the AA-genotype is found to be significantly associated with oral cancer (OR = 2.4, 95% CI = 1.7–3.2, p = 0.0001). A protein-protein docking analysis demonstrated that in the GG-genotype the binding geometry between c-Jun Kinase and GSTP1 was disrupted. It was validated by immunohistochemistry in human samples, showing lower c-Jun-phosphorylation and down-regulation of pro-apoptotic genes in normal oral epithelial cells with the AA-genotype. In silico docking revealed that AA-genotype weakly detoxifies the RAN/tobacco metabolites. In addition, experiments revealed a higher level of 8-Oxo-2′-deoxyguanosine induction in tumor samples with the AA-genotype. Thus, habit of using RAN/tobacco and GSTP1 AA-genotype together play a significant role in predisposition to oral cancer risk by showing higher DNA-lesions and lower c-Jun phosphorylation that may inhibit apoptosis.

Cytotoxic Effects of Betel Quid and Areca Nut Aqueous Extracts on Mouse Fibroblast, Human Mouth-Ordinary-Epithelium 1 and Human Oral Squamous Cell Carcinoma Cell Lines

Background:

Betel quid chewing is more common among the older generation in rural areas of Malaysia. Oral cancer in Asia has been associated with the habit of chewing betel quid and areca nut.

Objective:

This study aims to investigate the cytotoxic effects of betel quid and areca nut extracts on the fibroblast (L929), mouth-ordinary-epithelium 1 (MOE1) and oral squamous cell carcinoma (HSC-2) cell lines.

Methods:

L929, MOE1 and HSC-2 cells were treated with 0.1, 0.2 and 0.4 g/ml of betel quid and areca nut extracts for 24, 48 and 72 h. MTT assay was performed to assess the cell viability.

Results:

Both extracts, regardless of concentration, significantly reduced the cell viability of L929 compared with the control (P<0.05). Cell viability of MOE1 was significantly enhanced by all betel quid concentrations compared with the control (P<0.05). By contrast, 0.4 g/ml of areca nut extract significantly reduced the cell viability of MOE1 at 48 and 72 h of incubation. Cell viability of HSC-2 was significantly lowered by all areca nut extracts, but 0.4 g/ml of betel quid significantly increased the cell viability of HSC-2 (P<0.05).

Conclusion:

Areca nut extract is cytotoxic to L929 and HSC-2, whereas the lower concentrations of areca nut extract significantly increased the cell viability of MOE1 compared to the higher concentration and control group. Although betel quid extract is cytotoxic to L929, the same effect is not observed in MOE1 and HSC-2 cell lines. Further investigations are needed to clarify the mechanism of action.

Discoidin Domain Receptor-1 (DDR1) is Involved in Angiolymphatic Invasion in Oral Cancer

The discoidin domain receptor-1 (DDR1) is a non-integrin collagen receptor recently implicated in the collective cell migration of other cancer types. Previously, we identified an elevated expression of DDR1 in oral squamous cell carcinoma (OSCC) cells. Through the data mining of a microarray dataset composed of matched tumor-normal tissues from forty OSCC patients, we distilled overexpressed genes statistically associated with angiolymphatic invasion, including DDR1, COL4A5, COL4A6 and PDPN. Dual immunohistochemical staining further confirmed the spatial locations of DDR1 and PDPN in OSCC tissues indicative of collective cancer cell invasion. An elevated DDR1 expression at both the transcription and protein level was observed by treating keratinocytes with collagen of fibrillar or basement membrane types. In addition, inhibition of DDR1 kinase activity in OSCC TW2.6 cells disrupted cell cohesiveness in a 2D culture, reduced spheroid invasion in a collagen gel matrix, and suppressed angiolymphatic invasion in xenograft tissues. Taken together, these results suggest that collagen deposition in the affected tissues followed by DDR1 overexpression could be central to OSCC tumor growth and angiolymphatic invasion. Thus, DDR1 inhibitors are potential therapeutic compounds in restraining oral cancer, which has not been previously explored.

Patterns of tobacco and e-cigarette use status in India: a cross-sectional survey of 3000 vapers in eight Indian cities

Background

Tobacco smoking is one of the biggest and avoidable public health threats in the world, especially in low- and middle-income countries. India represents a highly complex public health environment due to the large number of smokers and complexities arising from tobacco use in different forms, including a variety of smokeless tobacco (SLT) products. Electronic cigarettes, an alternative nicotine delivery system with significantly less harmful emissions than smoke, could be an option for those who are unable to achieve smoking abstinence using other available means. This study, which we believe is the first of this kind in India, was conducted to obtain data on the characteristics and tobacco use profile of e-cigarette users (vapers) in India.

Methods

An interview-based survey was performed in the 8 largest metropolitan cities in India using a convenience sampling approach involving a total of 3000 subjects. Inclusion criteria were being a current e-cigarette user and aged 18 years or more. Interviewers were asked to continue recruitment until a total sample of 375 was reached in each target city.

Results

A total of 3000 vapers (81.4% males and 18.6% females, median age 29 years) participated to the study. The majority (80%) were first exposed to nicotine via tobacco smoking, SLT use, or both. Most of the subjects (79%) believed that e-cigarettes were less harmful than smoking. The vast majority of smokers (71.3%) reported smoking cessation (30.0%) or reduction in consumption (41.3%) with the help of e-cigarettes. Similar changes were observed in SLT users. Participants reported minimal side effects and some health benefits after e-cigarette use initiation.

Conclusion

Indian vapers who participated to this study were predominantly smokers and SLT users before e-cigarette use initiation, with the majority subsequently quitting or reducing tobacco use. Minimal side effects of e-cigarette were experienced, while some health benefits were also reported.

Areca catechu-From farm to food and biomedical applications

The family Arecaceae includes 181 genera and 2,600 species with a high diversity in physical characteristics. Areca plants, commonly palms, which are able to grow in nearly every type of habitat, prefer tropical and subtropical climates. The most studied species Areca catechu L. contains phytochemicals as phenolics and alkaloids with biological properties. The phenolics are mainly distributed in roots followed by fresh unripe fruits, leaves, spikes, and veins, while the contents of alkaloids are in the order of roots, fresh unripe fruits, spikes, leaves, and veins. This species has been reputed to provide health effects on the cardiovascular, respiratory, nervous, metabolic, gastrointestinal, and reproductive systems. However, in many developing countries, quid from this species has been associated with side effects, which include the destruction of the teeth, impairment of oral hygiene, bronchial asthma, or oral cancer. Despite these side effects, which are also mentioned in this work, the present review collects the main results of biological properties of the phytochemicals in A. catechu. This study emphasizes the in vitro and in vivo antioxidant, antimicrobial, anticancer, and clinical effectiveness in humans. In this sense, A. catechu have demonstrated effectiveness in several reports through in vitro and in vivo experiments on disorders such as antimicrobial, antioxidant, or anticancer. Moreover, our findings demonstrate that this species presents clinical effectiveness on neurological disorders. Hence, A. catechu extracts could be used as a bioactive ingredient for functional food, nutraceuticals, or cosmeceuticals. However, further studies, especially extensive and comprehensive clinical trials, are recommended for the use of Areca in the treatment of diseases.

Rationale and design of a randomized, controlled, superiority trial on areca nut/betel quid cessation: The Betel Nut Intervention Trial (BENIT)

Background

Areca nut (AN) is the seed endosperm of the Areca catechu L. palm and a Group 1 carcinogen chewed by 10–20% of the world population. AN is often chewed with Piper betle L. leaf, slaked lime, and tobacco to form a betel quid (BQ). The negative health effects associated with AN/BQ consumption warrant the need for an evidence-based cessation program. However, systematic research on AN/BQ cessation is rare.

Methods/design

The Betel Nut Intervention Trial (BENIT; trial #NCT02942745) is a randomized controlled trial designed to test the efficacy of an intensive AN/BQ cessation program. The trial is ongoing in Guam and Saipan with adult chewers who include tobacco in their BQ. Enrolled participants are assessed for their primary (chewing status) and secondary (saliva bio-verification) outcome at baseline, 22 days, and 6 months. Participants randomized into the control arm receive an educational booklet while those randomized into the intervention arm receive the educational booklet and a 22-day cessation program modeled after a smoking cessation program and led by trained facilitators. Information on chewing behavior (history, reasons for chewing, and AN/BQ composition and dependency) are collected. The intervention effectiveness is assessed using the logistic mixed model to compare cessation status between randomization groups.

Discussion

AN/BQ chewing affects a large population of people, many of whom live in low and moderate income countries in the Asia-Pacific region. Although the BENIT focuses on chewers in Guam and Saipan, it has the potential for greater regional and global importance.

Barriers to Quitting Areca Nut Consumption and Joining a Cessation Program as Perceived by Chewer and Nonchewer Populations in Guam

Background: Areca nut (AN) is a carcinogenic substance consumed by roughly 600 million individuals worldwide with increasing popularity in Guam. In response, a cessation program was developed and implemented in Guam and Saipan. However, to improve its delivery, it is necessary to understand the reasons influencing recruitment and participation, such as why a chewer may not want to quit or join a cessation program. Objective: To explore barriers inhibiting chewers from quitting AN chewing and from participating in a cessation program. Methods: Nine individual and group discussions were facilitated with a convenience sample of 17 chewers and nonchewers in Guam in 2017. The mean age of the participants was 36.4 years. Recurring themes relating to reasons for not quitting and not joining a cessation program were extracted. Results: Results produced three general categories-Sociocultural, Behavioral, and Accessible. Each category encompasses different attributes concerning reasons not to quit chewing (e.g. addiction, enabling community, or belief that AN is harmless), and reasons influencing lack of participation in a cessation program (e.g. time, transportation, or relatability). Conclusions: Current findings suggest chewers are unaware of the harmful effects of AN. Also, they may not comprehend the purpose of a cessation program. In addition, the likelihood of chewers participating in a cessation program is influenced by their level of comfort with the program and personnel, and whether a program addresses their time and transportation limitations.

Antidepressant-induced reduction in betel-quid use in patients with depression: A pioneer clinical study

Betel-quid is commonly used around the world and is listed as a Group I carcinogen. Prior research has suggested a possible association between antidepressants and betel-quid use. We aimed to clarify the effects of antidepressant therapy in betel-quid chewers in the population of patients with depression.We enrolled 204 patients with depressive disorders, collected their demographic information, and administered the Substance Use Severity Rating Scale for alcohol, cigarettes, and betel-quid and the Hamilton Depression Rating Scale. We compared betel-quid and non-betel-quid chewers and examined the effects of antidepressant therapy on betel-quid abstinence after previous exposure to betel-quid.Patients with depression were reported a higher prevalence of 26% betel-quid chewing habits and patients who chewed betel-quid showed more severe depressive symptoms. After antidepressant therapy, the addictiveness of betel-quid was significantly reduced by 4 times.This was a pioneering study showing that antidepressants could be a candidate for betel-quid cessation therapy. Future clinical trials are needed to verify their efficacy in reducing consumption for betel-quid addiction treatment.

Betel Nut (areca) and Smokeless Tobacco Use in Myanmar

Background: Betel nut (areca) is the world's fourth most commonly used addictive substance. Arecoline, a muscarinic agonist in areca, is also a partial agonist for the addiction-related high-affinity brain nicotine receptors. In many countries, smokeless tobacco is commonly mixed with areca. Objective: We sought to evaluate the knowledge of self-harm, and addiction associated betel quid use in an unban population. Methods: We conducted a survey study of 200 betel quid users in Yangon, Myanmar, and a survey of betel quid vendors to determine the relative amounts of areca and tobacco in the available quids. Results: The data determined that a large majority of the survey subjects (84%) used tobacco with their areca. Users had a general awareness that betel chewing was "a bad habit" (85%) and 80% were aware of the cancer risks. Understanding areca addiction remains a challenge since, aside from the strong muscarinic activity of arecoline stimulating salivation, overt neurologic effects are difficult for even the users to identify. Fifty eight percent of the respondents indicated that chewing betel quid had effects like drinking coffee, and 55.5% indicated that it had effects like drinking alcohol. Data obtained from the quid vendors indicated that 75% added tobacco in equal amounts to areca. Conclusion: The concomitant use of nicotine and areca indicates that betel quid addiction includes a significant component of nicotine dependence. However, the additional activities of areca, including the muscarinic effects of arecoline, indicate that potential cessation therapies should optimally address other factors as well.

Emerging Functions of Human IFIT Proteins in Cancer

Interferon-induced protein with tetratricopeptide repeats (IFIT) genes are prominent interferon-stimulated genes (ISGs). The human IFIT gene family consists of four genes named IFIT1, IFIT2, IFIT3, and IFIT5. The expression of IFIT genes is very low in most cell types, whereas their expression is greatly enhanced by interferon treatment, viral infection, and pathogen-associated molecular patterns (PAMPs). The proteins encoded by IFIT genes have multiple tetratricopeptide repeat (TPR) motifs. IFIT proteins do not have any known enzymatic roles. However, they execute a variety of cellular functions by mediating protein-protein interactions and forming multiprotein complexes with cellular and viral proteins through their multiple TPR motifs. The versatile tertiary structure of TPR motifs in IFIT proteins enables them to be involved in distinct biological functions, including host innate immunity, antiviral immune response, virus-induced translation initiation, replication, double-stranded RNA signaling, and PAMP recognition. The current understanding of the IFIT proteins and their role in cellular signaling mechanisms is limited to the antiviral immune response and innate immunity. However, recent studies on IFIT protein functions and their involvement in various molecular signaling mechanisms have implicated them in cancer progression and metastasis. In this article, we focused on critical molecular, biological and oncogenic functions of human IFIT proteins by reviewing their prognostic significance in health and cancer. Research suggests that IFIT proteins could be novel therapeutic targets for cancer therapy.

Chemistry, metabolism and pharmacology of carcinogenic alkaloids present in areca nut and factors affecting their concentration

Areca Nut (AN), the seed of tropical palm tree Areca catechu, is a widely chewed natural product with estimated 600 million users across the world. Various AN products, thriving in the market, portray 'Areca nut' or 'Supari' as mouth freshener and safe alternative to smokeless tobacco. Unfortunately, AN is identified as a Group 1 human carcinogen by International Agency for Research on Cancer (IARC). Wide variation in the level of alkaloids, broadly ranging from 2 to 10 mg/gm dry weight, is observed in diverse variety of AN sold worldwide. For the first time, various factors influencing the formation of carcinogenic alkaloids in AN at various stages, including during the growth, processing, and storage of the nut, are discussed. Current review illustrates the mechanism of cancer induction by areca alkaloids in humans and also compiles dose-dependent pharmacology and toxicology data of arecoline, the most potent carcinogenic alkaloid in AN. Careful monitoring of the arecoline content in AN can potentially be used as a tool in product surveillance studies to identify the variations in characteristics of various AN sample sold worldwide. The article will help to generate public awareness and sensitize the government bodies to initiate campaigns against AN use and addiction.

Treatment with the anti-diabetic drug metformin ameliorates betel-nut induced carcinogenesis in a murine model

BACKGROUND

Metformin, a widely used anti-diabetic drug has gained enormous attention as an anticancer agent. This study seeks to investigate the efficacy of metformin in ameliorating aqueous extract of betel-nut (AEBN) and arecoline induced carcinogenesis in a murine model.

METHODS

Swiss albino mice were exposed to AEBN (2 mg ml-1) and arecoline (10 μg ml-1) in drinking water for 16 weeks followed by co-administration of metformin (75 mg kg-1 or 150 mg kg-1) for 4 or 8 weeks. Histological changes and oxidative stress were assessed by haematoxylin and eosin staining, TBARS assay and protein carbonylation assay respectively. Lipid profile was determined using an automated analyzer. Expression of total and phosphorylated AMPK, ACC and p53 were determined by immunoblotting.

RESULTS

AEBN and arecoline induced dyslipidemia by downregulating AMPK (Thr-172) and activating ACC (Ser-79); they also downregulated tumor suppressor p53 (Ser-15). Metformin treatment induced AMPK-dependent alleviation of dyslipidemia in a dose and time dependent manner, upregulated p53 (Ser-15), restored tissue architecture and reduced oxidative stress in tissues of AEBN and arecoline treated mice.

CONCLUSION

This study establishes that betel nut induces dyslipidemia through its alkaloid, arecoline by inhibition of AMPK (Thr-172) and activation of ACC (Ser-79) and highlights the therapeutic potential of metformin for treatment of betel-nut induced carcinogenesis, indicating the repurposing of the old drug in a new avenue.