Genetic variability of the endangered fish lake minnow (Eupallasella percnurus) in populations newly established by translocation and those existing long term in Poland.

The lake minnow Eupallasella percnurus is a small leuciscid fish. In Poland, this species has been in a continuous decline since the mid-20th century and is presently considered as a extremely endangered. According to Polish law, E. percnurus is a strictly protected species that requires active conservation measures. In Poland, one the most common and effective measure of active protection E. percnurus is initiation of new populations. For this purpose, in 2004-2012, juvenile individuals originating from aquaculture conditions were translocated to group of isolated water bodies not inhabited by this species. The juveniles were offspring of parental fish belonging to the same local population, which is extinct at present. Five of those attempts were successful. The aim of the present study was to assess the genetic variation in a group new populations and compare genetic variation indicators with 13 old populations that had existed for decades. The polymorphism of 13 microsatellite markers was investigated, significance of differences in the genetic variation indicators between the groups were tested using a one-way analysis of variance (ANOVA). The mean values of all summary statistics under study, i.e. observed heterozygosity, expected heterozygosity and the total number of alleles, were higher in the group of new populations compared to almost all old ones. A similar dependence was found for Garza-Williamson M values, where the mean for the group of new populations was higher than in almost all old populations. Our results indicate that all recently established E. percnurus populations have not yet experienced any extensive founder effects or bottlenecks. They have preserved a large part of the genetic variability typical of their maternal population, which might also have been relatively high. This feature of new populations, may give them a relatively high ability to adapt to changing environments in the future.

Management of Genetic Variation in the Gamete Bank of the Endangered Lake Minnow Eupallasella percnurus, Using Genassemblage 2.2 Software.

The management of genetic resources deposited in gene banks requires knowledge of the genetic profiles of the gamete donors and bioinformatics tools to process this information. In this work, we show how to use Genassemblage 2.2 software in managing the genetic variation deposited in a bank of cryopreserved semen. Our demonstration was based on the leuciscid fish species, lake minnow Eupallasella percnurus, which is designated as endangered in Poland. The semen samples (n = 192) were taken from four Polish lake minnow populations and frozen in the gene bank. Fin clips were taken and DNA extracted. Across 13 investigated microsatellite loci, 21-53 alleles were identified in each population and 66 in the entire group of samples. The module "Management of genetic variation in gamete bank" of Genassemblage 2.2 software was used to find the set of samples that will preserve 100% of the detected allelic diversity in the next generation. Our results showed that a small group of 4-19 semen samples was enough to transfer all alleles detected across this set of samples. We, therefore, recommend Genassemblage 2.2 as a convenient tool for the detection of genetic differences between donors, the construction of optimal sets of samples for conservation of genetic variation, and for managing genetic variation deposited in gamete banks. Consequently, it can be used in breeding human-dependent populations and to optimize the use of genetic diversity in samples in the gamete banks. It can be especially useful for conserving populations of species characterized by low genetic variation, such as the lake minnow.

Influence of Arg399Gln, Arg280His and Arg194Trp XRCC1 gene polymorphisms of Base Excision Repair pathway on the level of 8-oxo-guanine and risk of head and neck cancer in the Polish population.

BACKGROUND: Reduced efficiency of DNA repair systems has long been a suspected factor in increasing the risk of cancer. OBJECTIVE: In this work we investigate influence of three selected polymorphisms of DNA repair gene XRCC1 and level of oxidative damage (measured as level of 8-oxo-guanine) on modulation of the risk of HNSCC. METHODS: In group of 359 patients with HNSCC (diagnosed with OSCC) the occurrence of polymorphic variants in Arg399Gln, Arg280His and Arg194Trp of XRCC1 were studied with TaqMan technique. In addition we determined level of 8-oxo-guanine with ELISA. RESULTS: Arg399Gln polymorphism and Arg194Trp polymorphism of XRCC1 gene increases the risk of HNSCC. The coexistence of Arg399Gln and Arg194Trp simultaneously enhances this effect. At the same time, their coexistence with His280His raises the risk to a level higher than in the absence of such coexistence, although the His280His itself is not associated with an increased risk of HNSCC. Patients have higher levels of 8-oxo-guanine than control group, and His280His is polymorphism with highest mean value of 8-oxoG level among studied. CONCLUSION: Patients with HNSCC not only have an increased level of 8-oxoguanine and the Arg399Gln and Arg/Trp of XRCC1 modulate risk of cancer, but there is also a relationship between these two phenomena, and it can be explained using intragenic combinations revealing that a high level of 8-oxoG could be a potential mechanism behind the modulation of HNSCC risk by the polymorphisms studied.

Genassemblage 2.0 software facilitates conservation of genetic variation of captively propagated species.

In conservation of captively propagated species, conserving genetic diversity is important. Here, we present an example of the use of Genassemblage 2.0 software in conserving the genetic variation of the lake minnow (Eupallasella percnurus). This fish has low genetic variation and is at risk of extinction in the western edge of its range, which includes Poland. Fish from one Polish population were captured (23 males, 25 females). Fin clips were taken, and DNA was extracted. Polymorphic microsatellites (13) were used to prepare genetic profiles, assess genetic variation in the fish and estimate genetic diversity in their progeny. Alleles were scored using an automatic capillary sequencer. The four and eight best variants of spawning pairs, and the optimal sets for group volitional breeding (four males, four females; eight males, eight females) were identified using Genassemblage 2.0. In the sets of 8 and 16 fish for group breeding, the mean heterozygosity, the number of alleles, and the share of "weak" heterozygotes (0.493, 24, 0.239 and 0.479, 23, 0.257, respectively) were better than the mean values for the progeny of all potential breeding pairs. For group volitional breeding, one set of four males and four females, and numerous sets of eight males and eight females would enable transmission of all 33 alleles identified in the potential broodstock and an expected progeny heterozygosity of 0.441 and 0.414, respectively. These expected heterozygosity values are higher than those in the broodstock. For practical purposes, the larger sets would be preferable for avoiding a future inbreeding and genetic drift.

Polymorphisms in the Bovine Tumour Necrosis Factor Receptor Type Two Gene (TNF-RII) and Cell Subpopulations Naturally Infected with Bovine Leukaemia Virus.

INTRODUCTION: Numerous mutations in the bovine tumour necrosis factor receptor type two (TNF-RII) gene have been identified, but their biological consequences remain poorly understood. The aim of this study was to determine whether polymorphism in the analysed loci of the bovine TNF-RII gene is linked with the size of cell subpopulations naturally infected with bovine leukaemia virus (BLV) which serve important immune functions in the host. MATERIAL AND METHODS: Samples originated from 78 cows. Polymorphisms in the studied gene were determined by PCR-RFLP and DNA sequencing by capillary electrophoresis. BLV infection was diagnosed by the immunofluorescence (IMF) technique and nested PCR. Cell subpopulations were immunophenotyped with IMF. RESULTS: Similar and non-significant differences in the average percentages of TNFα±, IgM+TNFα±, and CD11b+TNFα±cells infected with BLV were noted in individuals with various genotypes in the polymorphic sites g.-1646T > G and g. 16534T > C of the TNF-RII gene, and significant differences in the percentages of these subpopulations were observed between selected microsatellite genotypes (g.16512CA(n)). CONCLUSION: STR polymorphism and the number of CA dinucleotide repeats in intron 1 of the TNF-RII gene influence the frequency of TNF+, CD11b+TNF+, and IgM+TNF+ subpopulations naturally infected with BLV. Polymorphism in the gene's other two sites do not affect the size of these cell subpopulations.

Antioxidative assessment of new trans-palladium (II) complexes in head and neck cancer.

BACKGROUND: Head and neck neoplasms stand for 6% of all malignant neoplasms worldwide. Chemotherapy has limited use due to the biological properties of the tumor (in the majority of cases moderately and poorly differentiated squamous cell carcinoma). The fundamental molecule used in treatment is cisplatin and its derivates, that can be associated with fluorouracil. The new chemotherapeutic agents are not in common use during the treatment of head and neck malignancies. However, the use of low molecular weight complexes Pd (II) carries the potential of being more effective in therapy. MATERIAL AND METHODS: Fifty-one patients, 30 men and 21 women (aged 52.9 ± 12.1 years) with head and neck cancer were included in the study. Fifty-one healthy subjects, 31 men and 20 women, (aged 54.1 ± 14.7 years) years formed the control group. Antioxidant enzymes, superoxide dismutase, and catalase activities in erythrocytes were examined. RESULTS: An increased level of antioxidant enzymes was seen in the blood samples from patients with head and neck cancer after incubation with Pd (II) complex. In the group we obtained a statistically significant result p = <0.001. DISCUSSION: That project may contribute to the development of new, more efficient head and neck cancer treatment strategies. In our opinion, the results can be used in the future to develop a valuable prognostic marker of the disease. This is important because the initial phase of cancer is asymptomatic. The search for factors involved in pathogenesis translates into economic benefits and makes therapy more effectiveness through the reduction of treatment expenses.

Correction: Genetic Diversity of the Critically Endangered Lake Minnow Eupallasella percnurus in Poland and Its Implications for Conservation.

[This corrects the article DOI: 10.1371/journal.pone.0168191.].

Genetic Diversity of the Critically Endangered Lake Minnow Eupallasella percnurus in Poland and Its Implications for Conservation.

The lake minnow (Eupallasella percnurus) is critically endangered. In this paper we characterize the genetic properties of this fish over its range of occurrence in Poland and propose the use of this knowledge in its active protection. Twelve populations of lake minnow from across its range in Poland were investigated. 13 microsatellite loci were investigated to evaluate genetic variation and distance among populations. The magnitude of the genetic bottleneck or founder effects was investigated. In the studied populations, the allelic diversity and heterozygosity showed that genetic variation in this species is low. At most loci, only 2-3 alleles per population were detected. The average number of alleles detected across all loci was 35, and ranged from 24 to 53. The average observed heterozygosity (Ho) across all investigated loci was 0.38 (range 0.21-0.59); the average expected heterozygosity (He) was 0.36 (range 0.18-0.55). The populations remained in Hardy-Weinberg equilibrium. The average Garza-Williamson M index value for all populations was low (0.47), suggesting a reduction in genetic variation due to a founder effect or a genetic bottleneck. Genetic distance among populations was high or very high (FST range: 0.20-0.64; 뫵2 range: 1.32-16.98); this was likely a consequence of low gene flow among isolated populations, a founder effect or other genetic bottleneck, and strong genetic drift. The large genetic differences among the investigated lake minnow populations are likely to also exist among other populations of this species, and knowledge of these differences should inform active protection programs based on translocation of wild or cultivated fish of this species. The method presented here can potentially be applied to any population of lake minnows or closely related species.

TC2 C776G polymorphism studies in patients with oral cancer in the Polish population.

The first signs of oral cancer may resemble developing infections in the mucous membranes, with throat cancer symptoms being similar to those of upper respiratory tract infections. This greatly hinders rapid diagnosis and treatment. Better knowledge of the changes occurring in the metabolism of folic acid can help in understanding the carcinogenesis affecting DNA methylation and genome stability. Polymorphisms in genes encoding enzymes involved in this pathway may influence enzyme activity and thereby interfere with the concentrations of homocysteine and S-adenosylmethionine, which are important for DNA synthesis and cellular methylation reactions. The aim of the study was to determine the risk of oral cancer associated with the TC2 C776G polymorphism, as determined in 119 patients. Genotypes were determined by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). The test genotype was found to correspond to the Hardy-Weinberg (HW) equilibrium (p > 0.05). In our population G/G homozygosity of C776G TC2 gene polymorphism increases the risk of oral cancer; OR (odds ratio): 4.3875; 95% CI (confidence interval): 2.0518-9.319; p = 0.001. Regarding C/G genotype of the C776G TC2 gene, polymorphism also increases the risk of developing this cancer; OR 2.4146 95% CI: 1.2803-4.5541; p = 0.01.

Effect of copper(II) the activity of glutathione peroxidase in patients with head and neck cancer.

INTRODUCTION: Head and neck squamous cell carcinoma (HNSCC) accounts for about 6% of all malignant cancers. In the epidemiology of oral cavity neoplasm, important risk factors include: tobacco smoking, alcohol abuse, bad oral hygiene, papilloma virus infection, riboflavin and iron deficiency. OBJECTIVE: The objective of the investigation was a synthesis of Cu(II) complex and the evaluation of antioxidative enzymatic barrier in red blood cells of patients with head and neck tumor as well as in the control group. MATERIALS AND METHODS: For the investigation conduction, a consent of Bioethics Committee number RNN/142/09/KB was obtained. Blood for the examination was obtained from the patients of the Dapartment of Head and Neck Neoplasms Surgery Medical University of Lódz. The experiment was conducted on the group of 40 patients with HNSCC and 40 healthy people, using spectrophotometric method, glutathione peroxidase was marked. RESULTS: The investigation was conducted on the hemolysate obtained from the patients that were divided into two groups - a study group (1 and 2), which consisted of patients diagnosed with head and neck cancer and a control group (1 and 2) - healthy people. A significant statistical result for GPX occurred in control-1 and study-1 group with complex compound Cu(II) (p<0,001). CONCLUSIONS: Presented research prove, that complex compound Cis-dichlorobis(N1-hydroxymethyl-3methylpyrazole-κN2)copper (II) has an impact on the activity of the antioxidative GPX enzyme.

Splice-acceptor site mutation in p53 gene of hu888 zebrafish line.

The p53 transcription factor is a key tumor suppressor and a central regulator of the stress response, which has been a subject of intense research for over 30 years. Recently, a zebrafish line which carries splice site mutation (G>T) in intron 8 of p53 gene (p53 (hu888) ), encoding the p53 paralogue, was developed (The Zebrafish Mutation Project). To uncover molecular effects of the mutation, we raised hu888 zebrafish line to adulthood and analyzed DNA, mRNA data, and protein levels of p53 to assess their potential contribution in molecular mechanisms of the mutant fish. To obtain zebrafish individuals homozygous for the point mutation, p53 (hu888) carriers were repeatedly incrossed but only heterozygous mutants (p53 (hu888/+) ) or p53-wild type hu888 zebrafish (p53 (+/+) ) were identified in their progeny. By evaluation of p53 expression changes in the liver of mutant and wild type hu888 zebrafish as well as of Tübingen reference strain, we demonstrated that two types of splicing occurred in each case: a classical one and the alternative splicing which involves the activation of cryptic splice-acceptor site in the exon 9 of zebrafish p53 pre-mRNA. The alternative splicing event results in a deletion 12 nucleotides in the mature mRNA, and produces a shortened variant of p53 protein. Interestingly, expression of p53 protein in liver of both heterozygous and wild type hu888 zebrafish was highly reduced compared to that in the reference strain.

Signs, symptoms and the prevalence of fungi detected from the oral cavity and pharynx of radiotherapy subjects with head and neck tumors, and their susceptibility to chemotherapeutics.

Radio- and chemotherapy for malignant neoplasms, especially in head and neck region, is associated with a greater risk of fungal infections due to secondary alterations in the mucous membranes. The study had three aims: 1.to determine the signs and symptoms which occur among patients undergoing radiotherapy; 2. to determine the fungi prevalence in the mouth and throat of patients before, during and after radiotherapy; 3. to examine the sensitivity of strains to antimycotic drugs. The study comprised 44 patients (11 female, 33 male) with head and neck cancers,examined at the following stages: before radiotherapy (44 patients ­ batch 1), 3rd week of therapy (30 of the 44 patients­ batch 2), last day of therapy (28 of batch 2 ­ batch 3) and the 6th week after completion of radiotherapy (10 of batch 3 ­ batch 4). Clinical examination was performed and mycological status was estimated from an oral rinse on a selected medium. The fungal strains were isolated and sensitivity to antifungal drugs was determined. The most common symptoms were pain, dysphagia, and dysgeusia. Physical examination revealed signs of mucositis mainly among patients from batches 2 and 3. The presence of fungi in the mouth and throat was noted in over 2/3 (66.2%) of the patients from batch 1, and in 4/5 (80%) of batch 2. The fungi were detected in over half (57.1%) of patients from batch 3 and also in patients from batch 4. In all cases, fungi of various Candida species were identified: 6 species in batch 1,8 in batch 2, 6 in batch 3 and 5 in batch 4. The most frequently detected species was C. albicans, constituting 40­60%;the other species detected are known to be resistant to antimycotic drugs. The isolated strains were the most sensitive to nystatin and miconazole, and the least to ketoconazole and fluconazole. Conclusions: 1. Patients undergoing radiotherapy complain of pain, dysphagia, and dysgeusia; in most cases mucositis is diagnosed. 2. The high prevalence of fungi in the mouth and throat of patients treated by radiotherapy reinforces the need to perform mycological examinations in this group of patients to detect fungi, identify their species and determine of their sensitivity to drugs in order to prevent complications. 3. The species most frequently isolated from the patients are C. albicans and C.glabrata. The latter is characterized by resistance to the majority of antimycotic medications. 4. Most of the isolated strains are sensitive to nystatin and miconazole (applied locally) and to itraconazole (absorbed from the gastrointestinal tract).

Atypical lipomatous tumor of the cheek - a case report.

Liposarcoma is the most common soft tissue malignant tumor. It mostly arises in the subcutaneous tissue of shoulders, limbs and neck, and retroperitoneal space, but head occurrence is very rare. Atypical lipomatous tumor (ALT) is a well-differentiated liposarcoma (WDLPS) and constitutes 40-45% of all liposarcoma cases. A case of 57-year-old woman with a tumor of the left cheek, causing a discreet face asymmetry is presented. The tumor was soft and caused no tenderness. The patient reported no previous injury of the region. Fine-needle aspiration biopsy (FNAB) revealed atypical cells suspected of liposarcoma. MR examination showed fascicles of adipose tissue, which made the left cheek prominent. The patient was operated under general anaesthesia. Adipose tissue of the left cheek was removed. Postoperative course was uneventful. The final histopathological diagnosis - was atypical lipomatous tumor/well-differentiated liposarcoma (ALT/WDLPS). The patient remains under laryngological care. No recurrence of the disease has been observed during the 5 years follow-up.

Ribosomal intergenic spacer analysis as a tool for monitoring methanogenic Archaea changes in an anaerobic digester.

The applicability of a newly-designed PCR primer pair in examination of methanogenic Archaea in a digester treating plant biomass was evaluated by Ribosmal Intergenic Spacer Analysis (RISA). To find a suitable approach, three variants of RISA were tested: (1) standard, polyacrylamide gel-based, (2) automated, utilized capillary electrophoresis (GA-ARISA), and (3) automated microfluidics-based (MF-ARISA). All three techniques yielded a consistent picture of archaeal community structure changes during anaerobic digestion monitored for more than 6 weeks. While automated variants were more practical for handling and rapid analysis of methanogenic Archaea, the gel-based technique was advantageous when micro-organism identification was required. A DNA-sequence analysis of dominant bands extracted from the gel revealed that the main role in methane synthesis was played by micro-organisms affiliated with Methanosarcina barkeri. The obtained results revealed that RISA is a robust method allowing for detailed analysis of archaeal community structure during organic biomass conversion into biogas. In addition, our results showed that GA-ARISA has a higher resolution and reproducibility than other variants of RISA and could be used as a technique for tracking changes in methanogenic Archaea in an anaerobic digester.

Permanent genetic resources added to molecular ecology resources database 1 October 2012-30 November 2012.

This article documents the addition of 153 microsatellite marker loci to the Molecular Ecology Resources Database. Loci were developed for the following species: Brassica oleracea, Brycon amazonicus, Dimorphandra wilsonii, Eupallasella percnurus, Helleborus foetidus, Ipomoea purpurea, Phrynops geoffroanus, Prochilodus argenteus, Pyura sp., Sylvia atricapilla, Teratosphaeria suttonii, Trialeurodes vaporariorum and Trypanosoma brucei. These loci were cross-tested on the following species: Dimorphandra coccicinea, Dimorphandra cuprea, Dimorphandra gardneriana, Dimorphandra jorgei, Dimorphandra macrostachya, Dimorphandra mollis, Dimorphandra parviflora and Dimorphandra pennigera.

Polymorphism of the DNA repair genes RAD51 and XRCC2 in smoking- and drinking-related laryngeal cancer in a Polish population.

INTRODUCTION: Cigarette smoke and alcohol can generate reactive oxygen species, which may induce DNA double-strand breaks (DSBs), the most serious DNA lesion. In humans, DSBs are repaired mainly by non-homologous end joining and homologous recombination repair (HRR). Several polymorphisms in the DNA repair gene have been extensively studied in the association with various human cancers. In the present work we investigated the association between polymorphisms of two HRR genes, XRCC2 and RAD51, and tobacco- and alcohol-related larynx cancer in a Polish population. MATERIAL AND METHODS: Two polymorphisms of the XRCC2 gene, -41657C > T (rs718282) and 31479G > A (rs3218536), as well as one polymorphism of the RAD51 gene, -135G > C (rs1801320), were investigated by PCR-RFLP in 253 patients with larynx cancer and 253 age- and sex-matched non-cancer controls. RESULTS: Analysis of the gene-smoking and -drinking interactions revealed a weak association between larynx cancer and the -41657C > T polymorphisms of the XRCC2 gene among the moderate alcohol drinkers. The C allele of the -135G > C polymorphism of RAD51 increased cancer risk in the smoker group. Increased risk was also found for heavy drinkers. Additionally, there were no significant differences between distributions of genotypes in subgroups assigned to different TNM stages and grades. CONCLUSIONS: The results indicated that the -135G > C polymorphism of the RAD51 gene may be associated with smoking- and drinking-related larynx cancer in Poland.

Difficulties associated with the diagnosis of mycosis of the oral cavity and throat in chronic lymphocytic leukemia (CLL).

Cases of fungal infections are being encountered more often in clinical practice. The factors associated with a high risk of mycoses include, among others, corticosteroidotherapy, the administration antibiotics with wide spectrum of antibacterial properties, neutropenia, neoplasms. Fungi may play a role in cancer formation, may act as a complication in the course of treatment, and may mimic a neoplastic process by giving a similar clinical picture. In the case of fungal throat infection, patients complain of increased body temperature, a general feeling of weakness, malaise, headache, spontaneous pain intensifying during swallowing, a feeling of an obstacle in the throat or a cough. A physical examination may reveal congestion of the mucosa followed by a unilateral crater ulceration often covered with fat, as well as a thick coating, which is accompanied by foetor ex ore. The submandibular and neck lymph nodes are often greatly enlarged and painful. These symptoms may resemble those associated with the neoplastic process and changes in the course of systemic diseases (agranulocytosis). A correct diagnosis in these cases is necessary for adequate therapy. Chronic lymphocytic leukemia (CLL) is the most common type of leukemia among adults in Europe and North America. It is estimated that in Poland, CLL affects approximately 1,400 people per year. In this paper, a case of 62-years old patient with CLL with fungal infection of oral cavity and throat is presented.

The human aural myiasis caused by Lucilia sericata.

Myiasis is a rare, worldwide, human disease with seasonal variation, caused by developing larvae of a variety of fly species. It can be dangerous when infestations penetrate into the brain. In the available literature, we have found only a few papers concerning ear myiasis caused by Lucilia sericata. Here, we report 2 cases of aural myiasis. Early intervention (surgical removal, occlusion) in these cases should prevent complications. Larvae, for further examination, should be killed by immersion in very hot water, then preserved in an ethanol.

Cytotoxicity and genotoxicity of capecitabine in head and neck cancer and normal cells.

The interaction between a chemical and a cell may strongly depend on whether this cell is normal or pathological. Side effects of anticancer drugs may sometimes overcome their benefit action, so it is important to investigate their effect in both the target and normal cells. Capecitabine (Xeloda, CAP), a prodrug of 5-fluorouracil, is mainly used in colon cancer, but little is known about its action in head and neck cancer. We compared the cyto- and genotoxicity of CAP in head and neck HTB-43 cells and normal human lymphocytes by comet assay and flow cytometry. CAP at concentration up to 50 µM significantly decreased the viability of the cancer cells, whereas it did not affect normal lymphocytes. The drug did not interact with isolated plasmid DNA, but it damaged DNA in both cancer and normal cells. However, the extent of the damage in the former was much higher than in the latter. CAP induced apoptosis in the cancer cells, but not in normal lymphocytes. Pre-treatment of the cells with the nitrone spin traps α-(4-pyridil-1-oxide)-N-tert-butylnitrone and N-tert-butyl-α-phenylnitrone decreased the extent of CAP induced DNA damage, suggesting that free radicals may be involved in the formation of DNA lesions induced by CAP. The drug evoked an increase in the G0/G1 cell population accompanied by a decrease in the S cell population. CAP may evoke a pronounced cyto- and genotoxic effects in head and neck cancer cells, whereas it may or may not induce such effects in normal cells to far lesser extent.

The Cys326 allele of the 8-oxoguanine DNA N-glycosylase 1 gene as a risk factor in smoking- and drinking-associated larynx cancer.

Tobacco smoke-related products and ethanol would induce oxidative modifications to the DNA bases, thereby contributing to larynx cancer. Human 8-oxoguanine DNA N-glycosylase 1 (hOGG1) deals with oxidative DNA damage, and the base changes in the hOGG1 gene may alter the susceptibility of the human cells to tobacco smoke-related compounds and/or ethanol. In the present work, we investigated the association between smoking, drinking or the Ser326Cys polymorphism of the hOGG1 gene and the risk of larynx cancer in a Polish population. It has been reported that the Ser326 allele exhibits higher activity than the Cys326 variant. In this study, 253 age-matched controls and 253 patients with larynx cancer were enrolled. The polymorphism was determined with DNA from blood lymphocytes by polymerase chain reaction. The frequencies (%) of the genotypes were Ser/Ser 65.6, Ser/Cys 30.4, and Cys/Cys 4.0 in the controls and those in patients were 55.7, 36.0 and 8.3, respectively. Stratification of individuals according to their smoking and drinking habits indicated that these habits might be significant risk factors in larynx cancer. The Ser/Cys and Cys/Cys genotypes are significantly associated with the increased risk of larynx cancer. These genotypes increased the risk ratio of larynx cancer among heavy smokers, but did not change the risk in former smokers and moderate smokers. These genotypes also increased the risk of larynx cancer in moderate and heavy drinkers. Therefore, the Cys326 allele of the hOGG1 gene may increase the risk of larynx cancer associated with smoking or alcohol consumption.