Alcohol-related diseases of the mouth and throat

Long-term changes of salivary exoglycosidases and their applicability as chronic alcohol-drinking and dependence markers

OBJECTIVES

Investigation of long-term dynamic changes of salivary activity/output of exoglycosidases, deglycosylation processes and their applicability as alcohol markers.

METHODS

Exoglycosidase (α-fucosidase (FUC), β-galactosidase (GAL), β-glucuronidase (GLU), β-hexosaminidase (HEX, HEX A and HEX B isoenzymes) and α-mannosidase (MAN)) activities were measured in the saliva of healthy social drinking controls (C), alcohol-dependent non-smokers (ANS) and alcohol-dependent smokers (AS) at the 1st, 15th, 30th and 50th day of abstinence after chronic alcohol drinking.

RESULTS

The activity of exoglycosidases was 2-3-fold (MAN), 2-6 fold (FUC), 8-25-fold (HEX A) and 19-40-fold (GLU) higher in the ANS and AS groups than in controls, and had good/excellent sensitivity, specificity and accuracy. The higher outputs of exoglycosidases were in the AS and ANS groups than in controls at the 1st day (GLU, HEX A) and at the 50th day (GLU, FUC, MAN) of abstinence. We found numerous correlations between alcohol-drinking days with GLU and HEX A, alcohol amounts with HEX A and duration of alcohol dependence with FUC and MAN activity/output.

CONCLUSIONS

Salivary exoglycosidases/deglycosylation processes were still very high up to 50 days after the end of alcohol consumption. We found markers of chronic alcohol consumption (HEX A), alcohol dependence (FUC and MAN) and chronic alcohol consumption and dependence (GLU).

Salivary immune proteins monitoring can help detection of binge and chronic alcohol drinkers: Preliminary findings

BACKGROUND

We compared effects of binge and chronic alcohol drinking on oral health and salivary immunity proteins.

METHODS

The study involved males: 13 healthy social-drinking (C), 10 alcohol-dependent after chronic alcohol-intoxication (A), and 8 binge-drinkers after a single binge-drinking session (B). We compared periodontal/dental state and salivary immune proteins (lactoferrin -Lf, lysozyme -Lz, oral peroxidase -OPO, immunoglobulin A -IgA) in all groups.

RESULTS

Group A had worse dental and periodontal states than group C and B. Group B had a lower OPO activity and Lz concentration, and a higher IgA concentration in comparison to group C. Group A had a higher OPO activity than group C. Group B had a lower Lz and a higher LF and IgA outputs than C. Group A had a lower IgA output and a strong tendency of Lf and Lz outputs to be lower than in group C. Positive correlations were found between alcohol amounts and OPO and Lf output in group A, with no such correlations in group B. Only IgA concentration in group B and OPO activity in group A have potential to be markers that help to differentiate binge from chronic alcohol drinking, and OPO activity had better accuracy than IgA.

CONCLUSION

Binge alcohol consumption resulted in specific disturbances in salivary innate immunity (Lz), whereas chronic drinking led to disturbances in both adaptive and innate immunity (IgA, Lz and Lf). There is potential applicability of raised salivary IgA concentration and especially OPO activity in binge and chronic drinking detection and differential-diagnosis.

A study of DNA damage in buccal cells of consumers of well- and/or tap-water using the comet assay: Assessment of occupational exposure to genotoxicants

Because of concerns that natural aquifers in the region of Todos Santos (Baja California Sur, Mexico) might be contaminated by organochlorine pesticides and heavy metals, a case-control study was conducted among consumers and non-consumers of well- and/or tap-water to determine risks to human health. This study was based on a genotoxic evaluation of buccal cells using the Comet assay technique. Levels of DNA damage in the consumers group were significantly higher than those of the control group. However, occupational exposure to genotoxicants showed to be the critical factor rather than water consumption. Taking into account the professions of well- and/or tap-water consumers, agricultural workers exposed directly (those who fumigated) or indirectly (those not involved in fumigating) to agrochemicals showed greater genetic damage than controls. This difference persisted even when age, and whether the person smoked or consumed alcoholic drinks were considered. These factors were not associated with the level of genetic damage observed. Chemical analyses of organochlorine pesticides and heavy metals were carried out to evaluate the water quality of wells, faucets, and surface water of canals consumed by the population and/or used for irrigation. High concentrations of α and β endosulfan were detected in water of surface canals. Although our inventory of agrochemicals employed in the region showed the use of products considered carcinogenic and/or mutagenic, they were not detected by the analytical techniques used. Heavy metals (arsenic, mercury, and lead) were detected in water of some wells used for irrigation and human consumption. Environ. Mol. Mutagen. 58:619-627, 2017. © 2017 Wiley Periodicals, Inc.

Modulation by Ethanol of Cigarette Smoke Clastogenicity in Cells of Adult Mice and of Transplacentally Exposed Fetuses

Cigarette smoke (CS) and ethanol (EtOH) are known to synergize in the causation of cancers of the upper aerodigestive tract and of the liver. Little is known about possible interactions between these agents in other organs. These premises prompted us to evaluate the clastogenic effects resulting from the inhalation for 3 weeks of mainstream CS and oral administration of EtOH, which were tested either individually or in combination in cells of adult BDF1 mice and their fetuses. CS exerted clastogenic effects in haematopoietic cells of adult male mice by increasing the frequency of micronucleated erythroid cells both in bone marrow and in peripheral blood as well as the frequency of micronucleated and polynucleated pulmonary alveolar macrophages. Likewise, exposure to CS of pregnant mice resulted in a clastogenic damage in maternal bone marrow cells and in the liver and peripheral blood of their fetuses. Under all experimental conditions, EtOH was consistently devoid of clastogenic effects when given alone. In adult mice, EtOH exhibited a mild stimulating effect on the clastogenicity of CS in haematopoietic cells, while an opposite effect was observed in the respiratory tract, where EtOH attenuated the cytogenetic alterations induced by CS in pulmonary alveolar macrophages. At variance with the mild synergism observed in haematopoietic cells of adult mice, EtOH inhibited the clastogenicity of CS in the liver and peripheral blood cells of transplacentally exposed fetuses. Therefore, the effects of EtOH in CS-exposed mice show different trends depending both on the life stage and on the cells analyzed.

Alcohol, Aldehydes, Adducts and Airways

Drinking alcohol and smoking cigarettes results in the formation of reactive aldehydes in the lung, which are capable of forming adducts with several proteins and DNA. Acetaldehyde and malondialdehyde are the major aldehydes generated in high levels in the lung of subjects with alcohol use disorder who smoke cigarettes. In addition to the above aldehydes, several other aldehydes like 4-hydroxynonenal, formaldehyde and acrolein are also detected in the lung due to exposure to toxic gases, vapors and chemicals. These aldehydes react with nucleophilic targets in cells such as DNA, lipids and proteins to form both stable and unstable adducts. This adduction may disturb cellular functions as well as damage proteins, nucleic acids and lipids. Among several adducts formed in the lung, malondialdehyde DNA (MDA-DNA) adduct and hybrid malondialdehyde-acetaldehyde (MAA) protein adducts have been shown to initiate several pathological conditions in the lung. MDA-DNA adducts are pre-mutagenic in mammalian cells and induce frame shift and base-pair substitution mutations, whereas MAA protein adducts have been shown to induce inflammation and inhibit wound healing. This review provides an insight into different reactive aldehyde adducts and their role in the pathogenesis of lung disease.

The salivary β-HEX A% index as an excellent marker of periodontitis in smoking alcohol-dependent persons

Background. Severe periodontitis leading to tooth loss is found in 5–15% of most populations worldwide. Aim. The applicability of salivary β-hexosaminidase (β-HEX A%, percentage of β-HEX A isoenzyme to total β-HEX) and β-HEX B% (β-HEX B/β-HEX) indexes was investigated as a possible marker of periodontitis. Methods. Thirty three alcohol-dependent smokers (AS) and 32 healthy controls (C) were enrolled in the study. The activity of β-HEX was measured spectrophotometrically. Results. β-HEX A% was significantly higher and β-HEX B% was lower in AS than in C group. We found a significant correlation between β-HEX A% and gingival index (GI) and an inverse correlation between β-HEX A% and salivary flow (SF), in all groups. Salivary β-HEX A% index in smoking alcoholics at 0.23 had excellent sensitivity (96%) and specificity (91%); the AUC for β-HEX A% was high (0.937). There were no correlations between amount/duration-time of alcohol drinking/smoking and β-HEX A% or β-HEX B%. We found significant correlations between the time period of denture wearing and GI, papilla bleeding index (PBI), and decayed missing filled teeth index (DMFT) and between GI and the amount of smoked cigarettes per day. Conclusion. Bad periodontal state was most likely due to the nicotine dependence. Salivary β-HEX A% is a promising excellent marker for the diagnosis of periodontitis.

Salivary hexosaminidase in smoking alcoholics with bad periodontal and dental states

BACKGROUND

A sensitive alcohol marker, β-hexosaminidase (HEX), in the saliva of alcoholics, is investigated for the first time.

METHODS

The activity, specific-activity and output of total HEX and its isoenzymes HEX A and HEX B were measured in the saliva of healthy controls (C), alcohol-dependent non-smokers (ANS), and alcohol-dependent smokers (AS).

RESULTS

We observed a significantly increased activity/specific-activity and output of HEX A in the ANS and AS groups, due to the inflammatory state of the oral-cavity/salivary-glands. Significantly increased activity of HEX A contributed to an increase in the salivary activity of the total HEX in the ANS group. A significant decrease in the activity/specific-activity of HEX B in AS seemed to be due to HEX B inactivation by cigarette smoke. We noticed a tendency for deteriorated dental state (lower decayed-missing-filled-teeth index - DMFT), worse periodontal state (higher gingival index - GI and papilla-bleeding index - PBI) in AS, and worse periodontal state (higher GI) in ANS, as compared to the controls. We found no differences in the salivary protein concentrations between all groups and decreased salivary flow in both alcoholic groups as compared to the controls. In alcoholics, the area under the curve (AUC) for HEX A activity/specific-activity was significantly greater than for HEX and HEX B. The salivary HEX A activity/specific-activity had good/excellent sensitivity and specificity in smoking and non-smoking alcoholics, whereas salivary HEX and HEX B had poor/fair sensitivity and specificity.

CONCLUSIONS

Salivary HEX A may be helpful in the diagnosis of chronic alcohol intoxication, even in smokers.

The prevalence of substance use among patients at a dental school clinic in Michigan

BACKGROUND

Problematic alcohol use and illicit drug use are associated with a number of physical health consequences, including poor oral health. The authors evaluate the prevalence of problematic alcohol use and illicit drug use in adults who visited a dental school clinic.

METHODS

The authors recruited patients from the waiting area of the clinic. During recruitment, 85.9 percent of patients (n = 384) who the authors approached consented to participate in the study.

RESULTS

Overall, 20.6 percent of the participants reported either recent problematic alcohol use or illicit drug use; 7.4 percent of reported problematic alcohol use and 18.6 percent reported illicit drug use. The most common illicit drugs participants reported that they used were marijuana (16.8 percent), amphetamines (2.6 percent) and cocaine (1.1 percent). Participants who reported recent problematic alcohol use or illicit drug use were more likely to identify as white, were younger and did not have a spouse or partner.

CONCLUSIONS

There was a high prevalence of illicit drug use and problematic alcohol use among the patients seen at dental school clinic. These rates were higher than those in the general population.

CLINICAL IMPLICATIONS

The findings suggest that dental clinics are appropriate settings in which to identify and provide interventions for adults at risk of experiencing problems due to alcohol or drug use.

Detection of Cytomorphological Changes in Oral Mucosa among Alcoholics and Cigarette Smokers

OBJECTIVE

This study aimed to detect the cytomorphological changes in buccal mucosa among alcoholics and cigarette smokers.

METHODS

Buccal smears were collected from 200 volunteers; 50 were alcoholics, 50 were cigarette smokers, 50 were alcoholic and cigarette smokers, and another 50 were treated as a control group (neither drinkers nor smokers). The smokers and alcoholics included in this study had been continuously exposed for more than 5 years. Smears were stained using the Papanicolaou technique.

RESULTS

The cytological assessment in the alcoholics group revealed; atypical cellular changes detected in four individuals, bacteria was found in smears of 16 individuals; 18% cocci and 14% actinomyces species were also detected. Hyperkeratosis was detected in five individuals, while 25 individuals showed no oral changes. In the smokers group; atypical cellular changes were seen in six individuals and bacteria were detected in the smears of 15 individuals; 18% cocci and 12% Actinomyces species. Hyperkeratosis was observed in 14% of the individuals, but 44% showed no oral cytological changes. In the cigarette smoking and alcoholics group; atypical cellular changes were detected in only 14%, while bacteria were detected in 54% of smears; 32% were cocci and 16% were Actinomyces species. Changes in cells infected by human papilloma virus were detected in 4% and monilia in 2% of the cases. Also, 20% of the individuals showed hyperkeratosis and 12% showed no lesions.

CONCLUSION

The study proved that alcohol and cigarette smoking are risk factors for oral atypical cellular changes and possibly of oral infection. The degree of change depends on the duration of alcohol consumption and cigarette smoking.

Hh-Gli signaling pathway activity in oral and oropharyngeal squamous cell carcinoma

BACKGROUND

The aim of this study was to examine the role of Hh-Gli signaling in oral and oropharyngeal squamous cell carcinoma (SCC). The role of this signaling pathway in SCC formation has not yet been elucidated.

METHODS

Sixty-four tissue and blood samples were collected from 60 patients with SCC, all tobacco and alcohol users. An additional six buccal mucosa tissue samples were collected from nonsmokers and nondrinkers as control tissue.

RESULTS

Hedgehog-Gli pathway components were associated with clinical and pathologic features. Broders' grade and N stage were associated with higher Ptch1 and lower Gli1 expression. Tumor stage was negatively associated with Smo expression, and tumor size was positively associated with p16 expression. Ptch1 and Shh were frequently detected in the surrounding stroma. Ptch1 was found to be correlated with p16 expression, as well as with survivin expression.

CONCLUSIONS

The signaling pathway is activated in SCC and inducible in vitro by Shh protein.

Amount and type of alcohol consumption and missing teeth among community-dwelling older adults: findings from the Copenhagen Oral Health Senior study

OBJECTIVES

To study if an association between total weekly intake of alcohol, type-specific weekly alcohol intake, alcoholic beverage preference, and the number of teeth among older people exists.

METHODS

A cross-sectional study including a total of 783 community-dwelling men and women aged 65-95 years who were interviewed about alcohol drinking habits and underwent a clinical oral and dental examination. Multiple regression analyses were applied for studying the association between total weekly alcohol consumption, beverage-specific alcohol consumption, beverage preference (defined as the highest intake of one beverage type compared with two other types), and the number of remaining teeth (≤ 20 versus >20 remaining teeth).

RESULTS

The odds ratio (OR) of having a low number of teeth decreased with the total intake of alcohol in women, with ORs for a low number of teeth of 0.40 [95 percent confidence interval (CI) 0.22-0.76] in women drinking 1-14 drinks per week and 0.34 (95 percent CI 0.16-0.74) in women with an intake of more than 14 drinks per week compared with abstainers. Similar relations could also be obtained for type-specific alcohol intake of wine and for wine and spirits preference among women. Men who preferred beer showed a decreased risk for a low number of teeth compared with men with other alcohol preferences.

CONCLUSION

In this study, alcohol consumption, wine drinking, and wine and spirits preference among women were associated with a higher number of teeth compared with abstainers. Among men, those who preferred beer also had a higher number of teeth.

Reduced bone formation in alcohol-induced osteopenia is associated with elevated p21 expression in bone marrow cells in aldehyde dehydrogenase 2-disrupted mice

INTRODUCTION

High consumption of alcohol is one of the risk factors for osteoporosis. Approximately 45% of Chinese and Japanese individuals have the inactive aldehyde dehydrogenase 2 (Aldh2) phenotype. The absence of the ALDH2*2 allele is found to adversely influence the risk of osteoporosis. The aim of this study is to clarify the effects of alcohol consumption on osteoblast differentiation in bone marrow and trabecular bone formation in Aldh2-disrupted mice.

MATERIALS AND METHODS

Seven-week-old male Aldh2 knockout mice (Aldh2(-/-)) and wild-type (Aldh2(+/+)) mice were fed with water (groups Aldh2(-/-)/Wa and Aldh2(+/+)/Wa) or with 5% ethanol (groups Aldh2(-/-)/Al and Aldh2(+/+)/Al) for 4 weeks. At the age of 12 weeks, bone histomorphometry was performed at the secondary spongiosa of the tibias. Bone marrow cells from the bilateral femurs and tibias were used for mRNA expression analysis.

RESULTS

Histomorphometrical study revealed that trabecular bone was significantly reduced in the Aldh2(-/-)/Al group compared with that in the Aldh2(-/-)/Wa and Aldh2(+/+)/Wa groups. Bone formation rate was significantly decreased in Aldh2(-/-)/Al compared with the other three groups. Quantitative RT-PCR revealed a significant decrease in type I collagen, osterix, osteopontin, and osteocalcin mRNA expressions in Aldh2(-/-)/Al compared with Aldh2(-/-)/Wa. In bone marrow cell cultures, mineralized nodule formation in Aldh2(-/-)/Al was significantly decreased compared with that in Aldh2(+/+)/Wa and Aldh2(-/-)/Wa, while PAK18, a p21-activated kinase inhibitor, recovered the decreased mineralized nodule formation in Aldh2(-/-)/Al.

CONCLUSION

Alcohol consumption suppressed the differentiation and mineralization of osteoblasts and then reduced trabecular bone formation and bone volume in association with the elevated p21 expression in bone marrow cells, especially in aldehyde dehydrogenase 2-disrupted mice.

Nucleolar organizer regions (AgNOR) and subepithelial vascularization as field cancerization markers in oral mucosa biopsies of alcoholic and smoking patients

OBJECTIVE

The aim of this study was to show that variations in nucleolar organizer regions (AgNOR) and the increase in subepithelial vascularization could reveal changes related to markers of field cancerization in alcoholic and smoking patients who have not yet expressed clinical or histological malignant lesions.

STUDY DESIGN

Quantitative variations in epithelial AgNOR and in the vascularization of the underlying connective tissue were assessed by image analysis in histologically normal biopsy specimens from alcohol drinkers and smoking patients (DS). AgNORs were evidenced by silver staining and vessel walls were labeled by immunohistochemical demonstration of the CD34 antigen. Samples of oral mucosa of nonalcoholic, nonsmoking patients (NDS) obtained during surgical procedures served as controls. Eight parameters related to number, volume, and shape of nuclei and AgNORs, and 4 parameters related to number and diameter of vascular sections were evaluated. Differences between DS and NDS groups were statistically evaluated by means of ANOVA test and posterior Bonferroni comparisons.

RESULTS

The morphometric analysis revealed more irregular-shaped AgNORs in the superficial and suprabasal layers of the oral mucosa of DS patients. The suprabasal layers also exhibited a significantly larger number of AgNORs. The normal oral mucosa of DS patients exhibited a greater vascular density, with predominance of small-caliber blood vessels underlying the basement membrane.

CONCLUSION

The variations in AgNOR and epithelial vascularization would be practical biomarkers to evaluate changes underlying the augmented risk of cancerization in oral mucosa.

Diagnosis and treatment of deep neck space abscesses

Objective: To review our experience with deep neck abscesses and identify unique trends in our patient population.

Study Design: Case series with chart review.

Subjects and Methods: Evaluation of patients with deep neck space abscesses between 2001 and 2006. Peritonsillar abscess, superficial craniocervical infection, and salivary gland infections were excluded from selection of study population. A total of 106 cases were reviewed.

Results: Dental infections were the most common cause of deep neck abscesses (49.1%). Comorbidities included substance abuse (53.7%), psychiatric illness (10.4%), hypertension (9.4%), head and neck cancer (6.6%), and diabetes mellitus (5.7%). All patients received systemic antibiotics, eight patients required tracheotomy, 85 patients underwent surgical drainage in the operating room, and 11 had bedside drainage. Median and lower quartile of time in hospital was 2 and 3 days, respectively, whereas upper quartile was 4 days (range, 1 to 27 days). Patients with comorbidities or concurrent illness tended to stay longer ( P < 0.05, Mann-Whitney test). There were six complications and no mortality.

Conclusion: Substance abuse and poor orodental hygiene are important predisposing factors to deep neck abscesses. Appropriate management continues to favor a combination of early surgical drainage and systemic antibiotics.

Surgical debridement and adjunctive hyperbaric oxygen in cervical necrotizing fasciitis

Objective: To review our management of cervical necrotizing fasciitis (CNF) with the use of adjunctive hyperbaric oxygen therapy (HBO).

Study Design: Case series with chart review.

Subjects and Methods: Evaluation of ten patients with CNF between 2001 to 2006.

Results: There were five male and six female patients. Mean age was 43 ± 11 years. Eight cases resulted from an odontogenic source. Comorbidities included diabetes mellitus, hypertension, and substance abuse. All patients had computed tomography scans performed, received intravenous antibiotics, and underwent surgical debridement. Eight patients underwent surgery within 24 hours. The average number of debridements was 2.2 ± 0.8. Hospitalization was twice as long for diabetic patients (15.5 ± 8.16 days) compared with nondiabetic patients (7.5 ± 1.6 days, P = 0.029). Nine patients had HBO therapy. Combined data revealed a possible decrease in length of hospitalization with HBO therapy ( P < 0.001). No mortality was documented.

Conclusion: In addition to early and aggressive medical management and surgical debridement, this study suggests that HBO therapy is a beneficial adjunct by potentially decreasing length of hospitalization. Randomized trials are still needed to demonstrate its efficacy.

Effect of an alcoholic diet on dental caries and on Streptococcus of the mutans group. Study in rats

The objective of this study was to evaluate the effects of an alcohol diet on Streptococcus of the mutans group and on dental caries in the oral cavity of rats. Forty animals were divided into 3 groups according to the following liquid diets: 20% ethanol solution (Alcohol Group, AG), 27% sucrose solution (Isocaloric Group, IG), and water (Control Group, CG). After 56 days, samples were collected and plated on Mitis Salivarius Bacitracin agar to assess the number of colony forming units (CFU/mL) of Streptococcus of the mutans group. The animals were sacrificed and the jaws were removed in order to assess the occurrence of dental caries on the smooth and occlusal surfaces using stereomicroscopy. The data were submitted to ANOVA and Tukey test. The average numbers of CFU/mL (10(3)) were: 8.17 (AG), 9.78 (IG), and 5.63 (CG). There was no significant difference among the groups for the occurrence of occlusal caries. Regarding smooth surface caries, in the upper jaw, the caries number in the IG (1.58) was similar to that in the AG (2.06) and in the CG (1.14), and the number of caries in the AG was higher than in the CG; in the lower jaw there was significant difference among the 3 groups: AG (1.14), IG (2.00) and CG (0.43). The diets with the alcohol and sucrose solutions presented a tendency of increasing the colonization by Streptococcus of the mutans group and of increasing the occurrence of smooth surface dental caries in rat molars when compared to the control diet.

Genetic and environmental factors in head and neck cancer genesis

Head and neck squamous cell carcinoma (HNSCC) include squamous cell carcinomas of the oral cavity, pharynx, and larynx. Epidemiologic data suggest that the etiology and pathogenesis of HNSCC are influenced by environmental and lifestyle-related factors, such as tobacco use, ethanol consumption, papilloma virus infection, dietary factors and exposure to toxic substances. DNA repair systems and carcinogen-metabolizing enzymes can increase the risk for HNSCC but no definite causal mechanism has been demonstrated. There are several well-characterized entities that are associated with risk and prognosis of head and neck cancer, including Lynch-II syndrome, Bloom syndrome, Fanconi's anemia, xeroderma pigmentosum, ataxia telangiectasia, and Li-Fraumeni syndrome. This review aims to present the current status in our understanding of HNSCC and highlight controversies relating to the role of several factors in the genesis of the cancer.

Medical comorbidity and alcohol dependence

Alcohol dependence (AD) and, more generally, alcohol use disorders (AUDs) predispose individuals to adverse consequences that extend beyond the expected damage from alcohol-direct toxicity. Research has shown that the relationship of alcohol use to health outcomes is complex, as is the etiology of AD, and that the individual and social costs of alcohol-related problems are increasing. We review advances in alcohol science that explore the role of alcohol consumption and patterns of drinking in a range of medically comorbid conditions. Although new knowledge can assist in the development of appropriate medical management strategies, AUDs account for an important percentage of the global burden of disease and require approaches that are not uniquely focused on the identification and treatment of AD.

Selected genetic polymorphisms in MGMT, XRCC1, XPD, and XRCC3 and risk of head and neck cancer: a pooled analysis

Tobacco and alcohol consumption are the major risk factors for head and neck cancer, likely due to DNA-damaging processes. Genetic variations in DNA repair genes may affect an individual's susceptibility to head and neck cancer. Pooling data and DNA specimens from three case-control studies in western Washington State, North Carolina, and Puerto Rico, totaling 555 cases (430 whites) and 792 controls (695 whites), we studied the risk of head and neck cancer in relation to common nonsynonymous single-nucleotide polymorphisms in four DNA repair genes: MGMT (Leu84Phe and Ile143Val), XRCC1 (Arg399Gln), XPD (Lys751Gln), and XRCC3 (Thr241Met). All single-nucleotide polymorphisms were assayed in a single laboratory. Among whites, carriage of the MGMT Phe84 [odds ratio (OR), 0.71; 95% confidence interval (95% CI), 0.51-0.98] or Val143 (OR, 0.66; 95% CI, 0.47-0.92) allele was associated with a decreased risk of head and neck cancer; the haplotype distribution for MGMT differed significantly between cases and controls (covariate-adjusted global permutation test, P = 0.012). The XRCC1 GlnGln399 genotype was also associated with decreased risk among whites (OR, 0.56; 95% CI, 0.32-0.94), whereas XPD751 and XRCC3241 were not associated with risk. Alcohol-related risks tended to vary with DNA repair genotypes, especially for MGMT variants, whereas no effect modification was noted with tobacco use. Consistent findings from three case-control studies suggest that selected DNA repair enzymes may play a role in head and neck carcinogenesis.

Oxidative stress in alcohol-induced rat parotid sialadenosis

This study evaluated the effect of chronic ethanol consumption on the oxidative status of rat parotid and submandibular glands. To identify the endogenous response to ethanol ingestion, the activities of the antioxidant enzymes superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) were determined. In addition, the antioxidant alpha-tocopherol was supplied to the animals in order to estimate its action in ethanol-associated glandular damage. The thiobarbituric acid reactive substances (TBARS), and the protein carbonyl (PC) content, both markers of cellular oxidative stress on lipid and protein structures, respectively, were recorded. Animals subjected to alcohol ingestion showed a low body growth rate with concomitant enlargement of absolute and relative parotid wet weight, compared with pair-fed calorie-controlled rats. Parotid glands of ethanol-treated animals showed increased SOD and GPx activity, and alpha-tocopherol was able to reduce their activities to the control levels. TBARS and PC were enhanced after chronic ethanol treatment in rat parotids. Supplemental alpha-tocopherol suppressed the oxidative ethanol-induced damage in lipid without affecting induced protein oxidation. Submandibular glands revealed no alterations in the weight, enzymatic and oxidative parameters tested due to ethanol and/or alpha-tocopherol ingestion. These findings indicate the involvement of oxidative stress in parotid gland sialadenosis due to ethanol consumption and the capability of alpha-tocopherol to halt lipid damage, although this low-molecular antioxidant compound leads to neither increased glandular weight nor protein oxidation in ethanol-induced parotid alterations.

[Alcohol related diseases of the head and neck]

Chronic consumption of alcohol is an accepted social custom worldwide. In the upper aerodigestive tract, local morphologic, metabolic and functional alterations can be present due such consumption. Gastroesophageal reflux or alterations in sleep structure are typical examples of functional disorders. While alcohol was initially described as a risk enhancer only in smokers, a number of epidemiological studies have now shown that chronic alcohol consumption increases the risk of head and neck cancer independently of exposure to tobacco smoke. In addition, alcohol leads to an accumulation of pathologic microbes within the mucosa, leading to chronic infection. Susceptibility to carcinogens and cell proliferation in the mucosa are increased, resulting in genetic changes with the development of dysplasia, leucoplakia and carcinoma. Chronic alcohol consumption is correlated with an increased risk of cancer and increased mortality in a dose-dependent relationship. A number of biologically plausible mechanisms exist by which alcohol may cause cancer.