Application of simulation-based CYP26 SNP-environment barcodes for evaluating the occurrence of oral malignant disorders by odds ratio-based binary particle swarm optimization: A case-control study in the Taiwanese population.

INTRODUCTION: Genetic polymorphisms and social factors (alcohol consumption, betel quid (BQ) usage, and cigarette consumption), both separately or jointly, play a crucial role in the occurrence of oral malignant disorders such as oral and pharyngeal cancers and oral potentially malignant disorders (OPMD). MATERIAL AND METHODS: Simultaneous analyses of multiple single nucleotide polymorphisms (SNPs) and environmental effects on oral malignant disorders are essential to examine, albeit challenging. Thus, we conducted a case-control study (N = 576) to analyze the risk of occurrence of oral malignant disorders by using binary particle swarm optimization (BPSO) with an odds ratio (OR)-based method. RESULTS: We demonstrated that a combination of SNPs (CYP26B1 rs887844 and CYP26C1 rs12256889) and socio-demographic factors (age, ethnicity, and BQ chewing), referred to as the combined effects of SNP-environment, correlated with maximal risk diversity of occurrence observed between the oral malignant disorder group and the control group. The risks were more prominent in the oral and pharyngeal cancers group (OR = 10.30; 95% confidence interval (CI) = 4.58-23.15) than in the OPMD group (OR = 5.42; 95% CI = 1.94-15.12). CONCLUSIONS: Simulation-based "SNP-environment barcodes" may be used to predict the risk of occurrence of oral malignant disorders. Applying simulation-based "SNP-environment barcodes" may provide insight into the importance of screening tests in preventing oral and pharyngeal cancers and OPMD.

Higher Levels of Early Childhood Caries (ECC) Is Associated with Developing Psychomotor Deficiency: The Cross- Sectional Bi-Township Analysis for The New Hypothesis.

The aim of this study was to reassess and confirm the relationship between early childhood caries (ECC) and manifestations of psychomotor deficiency in 4-6-yr-old kindergarteners, which has remained elusive to date. A cross-sectional study with bi-township analysis was designed whereby 353 kindergarteners, aged 4-6 whose caries were greater (dmft (decayed, missing and filled teeth, dmft index) = 5.25) than that of the national average, located in a rural township of central Taiwan were recruited using simple random-selection. Besides the personal, demographic, and dietary information, the measurements for caries and the amended comprehensive scales (CCDI) of children's psychomotor development were used to address their relationship. One-way ANOVA vs. multiple linear regression were employed to compare the differences of variables between age, gender, BMI (Body Mass Index), and dmft scores vs. relationships among all variables, respectively. The results confirmed that there was a positive relationship between severe ECC (dmft > 3~8) and psychomotor deficiency (i.e., expressive language and comprehension-concept scales, etc.) amongst the kindergarteners analyzed. Our cross-sectional bi-township analysis has confirmed that there is indeed an association between severe ECC and psychomotor deficiency in kindergarteners, and we suggest that this may arise through critical stages of growth, not only via personal language communications, but psycho-social engagements as well. Therefore, a new hypothesis is proposed.

Patterns of Betel Quid, Cigarette, and Alcohol Use, and Their Correlates With Betel Quid Cessation in a Male Inmate Population.

BACKGROUND: There are few published studies addressing multiple substance uses and their effects on subsequent cessation of betel quid (BQ) chewing in the Asia Pacific region. OBJECTIVES: This study aims to investigate the usage patterns of BQ chewing, cigarette smoking, and alcohol drinking, and their correlates with subsequent BQ cessation among a male inmate population. METHODS: Data from 473 male inmates with a history of BQ use who were incarcerated in Taiwan Kaohsiung Prison was used for this analysis. Participants were asked to report their lifetime usage patterns of cigarette, alcohol, and BQ, and their cessation status of each substance. A stepwise logistic regression analysis was performed to identify predictors of voluntary BQ cessation. RESULTS: Seventy-five percent of all participants reported habitual use of all three substances. A total of 185 (39%) participants reported voluntary cessation of BQ prior to incarceration, and 288 (61%) reported cessation because of incarceration. Inmates who quit smoking before incarceration were more likely to voluntarily quit BQ. Inmates who had drinking habits were less likely to quit BQ, but those who quit drinking before incarceration were more likely to quit BQ. Inmates who preferred the type of BQ known as lao-hwa quid were more likely to quit BQ, and a longer chewing history correlated with a lower likelihood of quitting BQ. CONCLUSIONS IMPORTANCE: Our data suggest that coexisting habitual use of cigarette, alcohol, and BQ is very common in this inmate population. BQ cessation is significantly associated with not only inmates' usage patterns of cigarette and alcohol, but also their cessation status of these substances.

Association study between novel CYP26 polymorphisms and the risk of betel quid-related malignant oral disorders.

BQ chewing may produce significant amounts of reactive oxygen species (ROS), resulting in oral mucosa damage, and ROS may be metabolized by CYP26 families. Because the CYP26 polymorphisms associated with malignant oral disorders are not well known, we conducted an association study on the associations between the single nucleotide polymorphisms (SNP) of CYP26 families and the risks of malignant oral disorders. BQ chewers with the CYP26A1 rs4411227 C/C+C/G genotype and C allele showed an increased risk of oral and pharyngeal cancer (adjusted odds ratio (aOR) = 2.30 and 1.93, respectively). The CYP26B1 rs3768647 G allele may be associated with oral and pharyngeal cancer (aOR = 3.12) and OPMDs (aOR = 2.23). Subjects with the rs9309462 CT genotype and C allele had an increased risk of oral and pharyngeal cancer (aOR = 9.24 and 8.86, respectively) and OPMDs (aOR = 8.17 and 7.87, respectively). The analysis of joint effects between the CYP26A1 rs4411227 and CYP26B1 rs3768647/rs9309462 polymorphisms revealed statistical significance (aOR = 29.91 and 10.03, respectively). Additionally, we observed a significant mRNA expression of CY26A1 and CYP26B1 in cancerous tissues compared with adjacent noncancerous tissues. Our findings suggest that novel CYP26 polymorphisms are associated with an increased risk of malignant oral disorders, particularly among BQ chewers.

TGF-ß1 and IL-10 single nucleotide polymorphisms as risk factors for oral cancer in Taiwanese.

Cytokine production capacity varies among individuals and depends on cytokine gene polymorphisms. Transforming growth factor-beta 1 (TGF-ß1) plays a significant role in regulating the proliferation and apoptosis of epithelial cells. Interleukin 10 (IL-10) is an immunoregulatory cytokine with biological functions of anti-inflammation, immunosuppression, allergy, and anti-agenesis. The two cytokines are supposed to play an important role in carcinogenesis. The association between cytokine gene polymorphisms with oral cancer (OC) was investigated. We studied the association between the polymorphism in TGF-ß1 (G to C polymorphism at codon 25 <+915>) and IL-10 (-1082 G/A, -819 C/T, and -592 C/A) and the risk of OC in patients (n = 162) and healthy controls (n = 118) in Taiwan. All genotyping experiments were performed using the polymerase chain reaction sequence-specific primer (PCR-SSP) method. It was found that the codon 25 GC genotype of TGF-ß1 is significantly higher in frequency in patients with OC compared with a healthy control group (p < 0.0001). People with the GC genotype in codon 25 had an 11.09-fold increased risk of OC [odds ratio (OR) = 11.09; 95% confidence interval (CI) = 6.16-113.23]. IL-10 polymorphisms in -819 and -592 positions correlated with the risk of OC (p < 0.0001). The IL-10 -592 C allele-containing genotypes posed an increased risk of OC (OR = 1.79, 95% CI = 1.11-2.91). People with the CT genotype in IL-10 -819 had a 3.32-fold increased risk of OC (OR = 3.32; 95% CI = 1.64-6.94). The results suggest that polymorphisms in TGF-ß1 and IL-10 may have a significant influence on the development of OC.

Experience of Early Childhood Caries May Positively Correlate with Psychomotor Development.

PURPOSE: To examine the as yet unknown relationship between dental caries and the child's psychomotor development. MATERIALS AND METHODS: A cross-sectional study was designed by screening the kindergartens from urban areas of two cities in southern Taiwan. Besides the personal, demographic and dietary information, the common measures for caries (dmft) and the amended comprehensive scales (CCDI) for psychomotor development were used to assess their relationship(s). A power analysis showed that 334 subjects would be required. One-way ANOVA vs multiple linear regression analysis were used to compare the differences of variables between gender, age and dmft scales, vs the relationship among all variables tested, respectively. RESULTS: A total of 433 children completed the study. The results demonstrated that there was a positive relationship between higher (i.e. dmft≥4 and 5) but not lower or extremely high caries experience and aspects of psychomotor development (i.e. personal-social and expressive language) in children aged 4 to 6 years. CONCLUSION: The present results are important for paediatric dentists, as they suggest a positive correlation between caries experience (dmft 3 to 6) and psychomotor development in pre-school children and that such a correlation may occur more significantly as an attribute of the most affected teeth (incisors and molars) during the critical stage of personal-social and expressive language development (speech-communication).

Reasons for permanent tooth extractions in Taiwan.

There has been no study in Taiwan on reasons for extraction of permanent teeth. This study aimed to determine the reasons for permanent teeth extraction in Taiwan. This study performed a secondary data analysis based on the National Health Insurance Research Database. The 2009 database was adopted and there are 131 104 records of dental visits in the database; among them, 4958 visits (from 4811 patients) have a coding of extraction. The results showed that dental caries (55.3%) was the main reason for tooth extraction, followed by periodontal disease (22.1%). Extraction because of dental caries was commonly observed in all age-groups, and extractions because of periodontal disease increased in those older than 35 years. Maxillary and mandibular third molar were the most frequently removed tooth types, and most were extracted because of dental caries and impaction respectively.

Role of cytokine gene (interferon-γ, transforming growth factor-ß1, tumor necrosis factor-α, interleukin-6, and interleukin-10) polymorphisms in the risk of oral precancerous lesions in Taiwanese.

Oral squamous cell carcinoma can be preceded by some benign oral lesions with malignant potential, including leukoplakia, erythroplakia, oral lichen planus, and oral submucous fibrosis. There are different degrees of inflammatory cells infiltration in histopathology. Inflammatory cytokines may play a pathogenic role in the development of oral precancerous lesions (OPCLs). Genetic polymorphisms of cytokine-encoding genes are known to predispose to malignant disease. We hypothesized that the risk of OPCLs might be associated with cytokine gene polymorphisms of interferon (IFN)-γ, transforming growth factor (TGF)-ß1, tumor necrosis factor (TNF)-α, interleukin (IL)-6, and IL-10. In the present study, 42 OPCL patients and 128 controls were analyzed for eight polymorphisms in five different cytokine genes [IFN-γ (+874 T/A), TGF-ß1 (codons 10 T/C and 25 G/C), TNF-α (-308 G/A), IL-6 (-174 G/C), and IL-10 (-1082 A/G, -819 T/C, and -592 A/C)]. Cytokine genotyping was determined by the polymerase chain reaction sequence-specific primer technique using commercial primers. Allele and genotype data were analyzed for significance of differences between cases and controls using the Chi-square (χ(2)) test. Two-sided p < 0.05 were considered to be statistically significant. A series of multivariate logistic regression models, adjusted for age, sex, betel quid chewing, alcohol consumption, and smoking, was constructed in order to access the contribution of homozygous or heterozygous variant genotypes of polymorphisms. The TNF-α (-308) polymorphism was significantly associated with OPCLs. There were significant differences in the distribution of AA, GA, and GG genotypes between OPCL patients and controls (p = 0.0004). Patients with the AA or GA genotype had a 3.63-fold increased risk of OPCLs. The TGF-ß1 (codon 10 and 25) polymorphism was also significantly associated with OPCLs (p < 0.001). The IL-6 polymorphism was significantly associated with OPCLs. There are significant differences in the distribution of CC, GC, and GG genotypes between OPCL patients and controls (p < 0.001). Patients with the CC or GC genotype had a 35- or 20.59-fold increased risk of OPCLs. There were no significant differences in the distribution of IL-10 and IFN-γ genotypes between different groups of control individuals and OPCL patients. The IL-6, TGF-ß1, and TNF-α gene polymorphisms may have a significant association with the development of OPCLs.

Relationship between betel quid chewing and radiographic alveolar bone loss among Taiwanese aboriginals: a retrospective study.

BACKGROUND: Betel quid chewing is associated with the periodontal status; however, results of epidemiological studies are inconsistent. To the best of our knowledge, no study has reported radiographic alveolar bone loss (RABL) associated with betel quid chewing. METHODS: This survey was conducted in an aboriginal community in Taiwan because almost all betel quid chewers were city-dwelling cigarette smokers. In total, 114 subjects, aged 30-60 years, were included. Full-mouth intraoral RABL was retrospectively measured and adjusted for age, gender, and plaque index (PI). Multiple regression analysis was used to assess the relationship between RABL and potential risk factors. RESULTS: Age-, gender-, and PI-adjusted mean RABL was significantly higher in chewers with or without cigarette smoking than in controls. Multiple regression analysis showed that the RABL for consumption of 100,000 pieces betel quid for the chewer group was 0.40 mm. Full-mouth plotted curves for adjusted mean RABL in the maxilla were similar between the chewer and control groups, suggesting that chemical effects were not the main factors affecting the association between betel quid chewing and the periodontal status. CONCLUSION: Betel quid chewing significantly increases RABL. The main contributory factors are age and oral hygiene; however, the major mechanism underlying this process may not be a chemical mechanism. Regular dental visits, maintenance of good oral hygiene, and reduction in the consumption of betel quid, additives, and cigarettes are highly recommended to improve the periodontal status.

The influence of monoamine oxidase variants on the risk of betel quid-associated oral and pharyngeal cancer.

Betel quid (BQ) and areca nut (AN) (major BQ ingredient) are group I human carcinogens illustrated by International Agency for Research on Cancer and are closely associated with an elevated risk of oral potentially malignant disorders (OPMDs) and cancers of the oral cavity and pharynx. The primary alkaloid of AN, arecoline, can be metabolized via the monoamine oxidase (MAO) gene by inducing reactive oxygen species (ROS). The aim of this study was to investigate whether the variants of the susceptible candidate MAO genes are associated with OPMDs and oral and pharyngeal cancer. A significant trend of MAO-A mRNA expression was found in in vitro studies. Using paired human tissues, we confirmed the significantly decreased expression of MAO-A and MAO-B in cancerous tissues when compared with adjacent noncancerous tissues. Moreover, we determined that MAO-A single nucleotide polymorphism variants are significantly linked with oral and pharyngeal cancer patients in comparison to OPMDs patients [rs5953210 risk G-allele, odds ratio = 1.76; 95% confidence interval = 1.02-3.01]. In conclusion, we suggested that susceptible MAO family variants associated with oral and pharyngeal cancer may be implicated in the modulation of MAO gene activity associated with ROS.

miRNA-491-5p and GIT1 serve as modulators and biomarkers for oral squamous cell carcinoma invasion and metastasis.

MicroRNAs offer tools to identify and treat invasive cancers. Using highly invasive isogenic oral squamous cell carcinoma (OSCC) cells, established using in vitro and in vivo selection protocols from poorly invasive parental cell populations, we used microarray expression analysis to identify a relative and specific decrease in miR-491-5p in invasive cells. Lower expression of miR-491-5p correlated with poor overall survival of patients with OSCCs. miR-491-5p overexpression in invasive OSCC cells suppressed their migratory behavior in vitro and lung metastatic behavior in vivo. We defined the G-protein-coupled receptor kinase-interacting protein 1 (GIT1)-as a direct target gene for miR-491-5p control. GIT1 overexpression was sufficient to rescue miR-491-5p-mediated inhibition of migration/invasion and lung metastasis. Conversely, GIT1 silencing phenocopied the ability of miR-491-5p to inhibit migration/invasion and metastasis of OSCC cells. Mechanistic investigations indicated that miR-491-5p overexpression or GIT1 attenuation reduced focal adhesions, with a concurrent decrease in steady-state levels of paxillin, phospho-paxillin, phospho-FAK, EGF/EGFR-mediated extracellular signal-regulated kinase (ERK1/2) activation, and MMP2/9 levels and activities. In clinical specimens of OSCCs, GIT1 levels were elevated relative to paired normal tissues and were correlated with lymph node metastasis, with expression levels of miR-491-5p and GIT1 correlated inversely in OSCCs, where they informed tumor grade. Together, our findings identify a functional axis for OSCC invasion that suggests miR-491-5p and GIT1 as biomarkers for prognosis in this cancer.

Polymorphism of angiotensin I-converting enzyme gene is related to oral cancer and lymph node metastasis in male betel quid chewers.

OBJECTIVES: Angiotensin I-converting enzyme (ACE), a type I cell surface zinc metallopeptidase, is differentially expressed in several malignancies and plays a role in tumor cell proliferation, tumor cell migration, angiogenesis, and metastatic behavior. We aimed to investigate the effects of ACE gene (rs1799752) variants on oral cancer risk. MATERIALS AND METHODS: Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) 32 was used to measure ACE gene polymorphisms in 88 patients with oral precancerous lesion (OPL), 186 33 patients with oral cancer, and 120 control subjects without any oral lesions. All study subjects were male 34 betel quid chewers. RESULTS: Patients with oral cancer or OPL had a higher frequency of the DD genotype than the control patients did. Oral cancer patients with the DD genotype had a significantly higher prevalence of lymph node metastases than patients with the II/ID genotype did. After adjusting for age, smoking, drinking, and betel quid chewing status, we found that individuals with the DD genotype of the ACE gene had a 5.46-fold and 3.13-fold higher risk of developing oral cancer or OPL, respectively, than those with the II genotype did. Furthermore, oral cancer patients with the DD genotype of the ACE gene had a 2.16-fold higher likelihood of lymph node metastasis. CONCLUSION: Our data suggest that the ACE gene polymorphisms may be associated with increased susceptibility to OPL and oral cancer and lymph node metastasis from oral cancer.

Population burden of betel quid abuse and its relation to oral premalignant disorders in South, Southeast, and East Asia: an Asian Betel-quid Consortium Study.

OBJECTIVES: We investigated the population burden of betel quid abuse and its related impact on oral premalignant disorders (OPDs) in South, Southeast, and East Asia. METHODS: The Asian Betel-Quid Consortium conducted a multistage sampling of 8922 representative participants from Taiwan, Mainland China, Malaysia, Indonesia, Nepal, and Sri Lanka. Participants received an interviewer-administered survey and were examined for oral mucosal disorders. RESULTS: The prevalence of betel quid abuse was 0.8% to 46.3% across 6 Asian populations. The abuse frequency was over 40.5% for current chewers, with the highest proportion in Nepalese and Southeast Asian chewers (76.9%-99.6%). Tobacco-added betel quid conferred higher abuse rates (74.4%-99.6%) among Malaysian, Indonesian, and Sri Lankan men than did tobacco-free betel quid (21.8%-89.1%). Gender, lower education level, younger age at chewing initiation, and clustering of familial betel quid use significantly contributed to higher abuse rates. Indonesian betel quid abusers showed the highest prevalence of OPDs and had a greater risk of OPDs than did nonabusers. CONCLUSIONS: Betel quid abuse is high in regions of Asia where it is customarily practiced, and such abuse correlates highly with OPDs. By recognizing abuse-associated factors, health policies and preventive frameworks can be effectively constructed to combat these oral preneoplasms.

Monoamine oxidase A variants are associated with heavy betel quid use.

Few studies have investigated whether genetic abnormalities predispose individuals to heavy betel quid (BQ) use. One of the major ingredients of BQ, arecoline, is known to affect the expression of monoamine oxidase A (MAO-A). We investigated the extent to which arecoline inhibits MAO-A expression and the role of MAO-A polymorphisms in BQ use in Taiwanese aborigines. Cytotoxicity assays, microarrays and quantitative reverse transcriptase-polymerase chain reaction were used to examine the effects of arecoline and areca nut extract (ANE) on cell viability and MAO-A expression in neuroblastoma SH-SY5Y cells. After identifying the effective concentrations of arecoline and ANE in vitro, we examined the in vivo effects of these compounds using a rat model system. Our results indicate that arecoline and ANE inhibit MAO-A expression both in vitro and in vivo. In addition, we examined the correlation between plasma MAO-A activity and cumulative exposure to BQ in humans. We recruited 1307 aborigines from a large-scale community-based survey to determine whether MAO-A variants were associated with high BQ use and a preference for use with smoking or alcohol and whether gender bias existed. MAO-A expression was significantly downregulated by arecoline and ANE at 100-200 µg/ml and in rat whole brains on days 30 and 45. MAO-A activity levels in human plasma were positively correlated with the extent of BQ exposure, and individuals with at-risk alleles exhibited lower activity, although this result did not reach statistical significance. We found two single nucleotide polymorphism (SNPs) in aboriginal males [rs2283725, odds ratio (OR) = 2.04; rs5953210, OR = 2.03] and females (rs2283725, OR = 1.54; rs5953210, OR = 1.59) that were associated with heavy BQ use. Those individuals carrying at-risk alleles who drank alcohol were twice as likely to be heavy BQ users. However, the effects of these SNPs on BQ use were significant even after controlling for alcohol use. Our results suggest that two specific loci may confer a susceptibility to BQ abuse and affect MAO-A enzymatic activity.

Development and validation of a self-rating scale for betel quid chewers based on a male-prisoner population in Taiwan: the Betel Quid Dependence Scale.

BACKGROUND: Betel quid is a substance that commonly used among male labor in Taiwan, and the dependence potential has been reported in some studies, but no instrument has been developed specifically to assess areca/betel quid dependence. OBJECTIVE: To develop a reliable and valid research instrument/screening tool for the measurement of betel quid dependence. METHODS: There were 223 male prisoners with a history of betel quid chewing behavior before they were incarcerated in Kaohsiung Prison enrolled in this study. The items of the Betel Quid Dependence Scale (BQDS) were developed by the authors and were designed referring to previous research findings and the diagnostic criteria of Substance Dependence in DSM-IV. RESULTS: The BQDS has high internal consistency (Cronbach's α=0.921), and a three-factor structure consisting of "physical and psychological urgent need," "increasing dose" and "maladaptive use," which accounted for 61.2% of the total variance. There were 94 (42.2%) male-prisoners who satisfied DSM-IV criteria for dependent use, and the receiver operating characteristic (ROC) curve showed that the BQDS had an optimal cut-off score of 4, the optimal sensitivity was 0.926 and the specificity was 0.977, with the predictive accuracy up to 99.3%. CONCLUSIONS: The BQDS has good internal consistency and construct validity, and was proved to have optimal reliability and criterion validity in this special sample. Further investigation is suggested in different samples such as the general population or oral submucous fibrosis (OSF) patients to test the generalization of this instrument.

The neoplastic impact of tobacco-free betel-quid on the histological type and the anatomical site of aerodigestive tract cancers.

Little is known about any consequences of swallowing tobacco-free betel-quid (TF-BQ) juice/remnants following chewing and its carcinogenic impact on the upper aerodigestive tract (UADT) to gastrointestinal tract (GIT). We investigated the neoplastic impact of TF-BQ on different anatomical locations along UADT and GIT, and differences according to their histological categories. We conducted a multicenter case-control study examining patients with 2,163 pathology-proven UADT and GIT cancers, comparing them with 2,250 control subjects. Generalized additive models, piecewise regression and polytomous logistic models were applied to identify possible dose-dependent structures and cancer risks. Contrary to nonsignificant GIT-adenocarcinoma risk (aOR=0.9), TF-BQ users experienced a 1.7- to 16.2-fold higher risk of UADT-squamous cell carcinomas than nonusers, with the peak risk discovered in oral neoplasms. We separately observed a curvilinear and linear TF-BQ dose-risk relationship in oral/pharyngeal/esophageal and laryngeal cancers. Chewers of betel inflorescence were generally at a greater UADT cancer risk. A higher first-piecewise increased risk of esophageal cancer was recognized among areca-fluid swallowers than among nonswallowers (continuous aOR=1.12 vs. 1.03). TF-BQ use accounted for 66.1-78.7% and 17.8-33.2% of the cases of oral/pharyngeal and esophageal/laryngeal cancers, respectively. However, a reduction from heavy TF-BQ consumption to low-to-moderate consumption only reduced 11.3-34.6% of etiologic fraction of oral/pharyngeal cancers. Alcohol supra-additively modified the risk of TF-BQ in determining the development of oral, pharyngeal and esophageal cancers. In conclusion, the interplay of TF-BQ and alcohol/tobacco use, combined with how chewing habit is practiced, influences carcinogenic consequences on anatomically diverse sites of UADT and GIT cancers, and histologically different types.

CYP26B1 is a novel candidate gene for betel quid-related oral squamous cell carcinoma.

Substantial epidemiological data suggest a role for environmental factors (for example, the use of alcohol, betel quid (BQ), and cigarettes) in the occurrence of oral squamous cell carcinoma (OSCC), but the evidence for the genes involved has been inconsistent. This study was to investigate the role of CYP26B1, together with the use of alcohol, BQ, and cigarettes, on BQ-related OSCC. The association study (247 OSCC cases and 338 controls) was conducted to examine the possible interplay between CYP26B1 polymorphisms and alcohol, BQ, and cigarettes use. Additional gene expression was evaluated between OSCC tissue and adjacent normal tissue. The genetic polymorphism AA of CYP26B1 appeared to correlate with the risk of OSCC (OR=2.26; 95% CI, 1.35-3.80). Chewing BQ multiplicatively interacted with CYP26B1 AA to increase the OSCC risk (aOR=70.04; 95% CI, 13.62-360.11). The independent risk of OSCC was observed among BQ chewers with CYP26B1 AA, and compared with chewers with the CYP26B1 CC genotype (stratified aOR=2.88; 95% CI, 1.07-7.74). Increased expression of CYP26B1 was observed in tumor tissue compared with adjacent normal tissue. The CYP26B1 gene plays a novel role in the BQ dependent pathogenesis of OSCC.

Human dental pulp stem cells derived from different cryopreservation methods of human dental pulp tissues of diseased teeth.

BACKGROUND: Successful isolation of human dental pulp stem cells (hDPSCs) has been documented at least 120h after tooth extraction. Viable hDPSCs have been isolated chiefly from cryopreserved healthy molar teeth and their undigested dental pulp tissue. Isolation of hDPSCs from diseased but vital teeth after cryopreservation has not been reported. This study aimed to isolate hDPSCs from cryopreserved diseased but vital teeth of various tooth types. MATERIALS: Fifty tooth samples were divided into group A (n = 20) - freshly derived dental pulp tissues, group B (n = 20) - liquid nitrogen (liq N(2) )-stored dental pulp tissues and group C (n = 10) - liq N(2) -stored intact teeth. METHODS AND RESULTS: The success rate for hDPSCs isolation was 100% for groups A and B and only 20% for group C. hDPSCs from all groups demonstrated self-renewal properties and similar multipotent potential characteristics of adipogenic, chondrogenic and osteogenic differentiation. In addition, hDPSCs showed high expression of bone-marrow mesenchymal stem-cell markers (CD29, CD90 and CD105) and very low expression of specific hematopoietic cells markers (CD14, CD34 and CD45). CONCLUSION: Our results indicate that hDPSCs isolated from diseased but vital teeth of various tooth types can be stored in liq N(2) for future usage.

The use of tobacco-free betel-quid in conjunction with alcohol/tobacco impacts early-onset age and carcinoma distribution for upper aerodigestive tract cancer.

BACKGROUND: Recognition of how risk factors affect the age when cancers are first diagnosed may help to establish more appropriate cancer screening and preventive strategies. METHODS: To investigate the independent and synergistic effects of alcohol, tobacco-free betel-quid (TF-BQ), and cigarette use on diagnosis age and dissemination of upper aerodigestive tract squamous cell carcinoma (UADT-SCC), we recruited pathology-proven 1522 patients with UADT-SCC for study. RESULTS: A 49-, 53-, 57-, and 62-year-old stepwise older median age at carcinoma diagnosis was, respectively, found among patients with oral, pharyngeal, esophageal, and laryngeal cancer. Oral cavity (53.2%) and larynx (11.6%) were separately the dominant and recessive sites where the UADT-SCC occurred. Although alcohol and tobacco bestowed increased risks of earlier tumor occurrence only for oral/pharyngeal and oral cancers, respectively, TF-BQ was consistently observed to confer elevated age-associated risks for each UADT-SCC [adjusted hazard ratio (aHR) = 1.6-2.3]. Alcohol and TF-BQ joint consumers experienced a stepwise increased cumulative risk (CR) of contracting carcinomas of the larynx (46.2%), esophagus (47.5%), pharynx (53.5%), and oral cavity (60.5-71.0%), with >68% of CRs found among drinkers who started chewing before age 20. Alcohol + Betel + Cigarette and Alcohol + Betel users exhibited earlier diagnosis ages than non-users: 10 years ahead for oral cancer, 7, 17, and 12 years earlier for pharyngeal, esophageal, and laryngeal cancers. Noticeably, higher cumulative cancer risks regarding earlier tumor occurrence were correspondingly identified for these users aged 43, 49, 43, and 44 upward. CONCLUSIONS: Tobacco-free betel-quid, in conjunction with alcohol and/or tobacco consumption, impacts early cancer occurrence for specific UADT-SCC and influences tumor site incidence pattern of these neoplasms.