ABSTRACT
BACKGROUND: DACT genes regulates Wnt as well TGF-ß pathway, and were already associated with hepatocellular and lung cancer. Alterations on Wnt/ß-catenin were associated with head and neck cancer through ß-catenin cytoplasmatic accumulation. OBJECTIVE: The aim of the study was to evaluate DACT1 and DACT2 expression and methylation on oral squamous cell cancer (OSCC). METHODS: 47 samples of salivary rinse and tissue were collected from 29 OSCC and 18 control patients. qMSP and RT-PCR reactions were performed in order to detect hypermethylation and expression of DACT1 and DACT2 genes. Statistical analysis was conducted to evaluate these genes as possible biomarkers for OSCC. RESULTS: As expected man over 60 years old with tobacco and alcohol consumption history were associated with OSCC. There was no statistical difference between groups concerning DACT1 and DACT2 either in promoter hypermethylation or transcript levels. Age was associated with DACT2 promoter hypermethylation, especially over 56 years old. CONCLUSION: Patients older than 56 years old were about 5 times more likely to have DACT2 promoter hypermethylation. These findings could partially explain why older subjects are more prone to carcinogenesis. Wnt/ß-catenin pathway plays an important role in carcinogenesis, and the study of their regulators may help understand malignant transformation.
Subject(s)
Adaptor Proteins, Signal Transducing/genetics , Carcinoma, Squamous Cell/genetics , Carrier Proteins/genetics , Gene Expression Regulation, Neoplastic , Head and Neck Neoplasms/genetics , Mouth Neoplasms/genetics , Neoplasm Proteins/genetics , Nuclear Proteins/genetics , Adaptor Proteins, Signal Transducing/biosynthesis , Age Factors , Carcinoma, Squamous Cell/metabolism , Carrier Proteins/biosynthesis , Case-Control Studies , Cell Line, Tumor , DNA Methylation , Epigenesis, Genetic , Female , Head and Neck Neoplasms/metabolism , Humans , Male , Middle Aged , Mouth Neoplasms/metabolism , Neoplasm Proteins/biosynthesis , Nuclear Proteins/biosynthesis , Promoter Regions, Genetic , Prospective Studies , Squamous Cell Carcinoma of Head and NeckABSTRACT
BACKGROUND: The capacity for DNA repair is essential in maintaining cellular functions and homeostasis; however, this capacity can be altered based on DNA sequence variations in DNA repair genes, which may contribute to the onset of cancer. Many single-nucleotide polymorphisms (SNPs) in repair genes have been found to be associated with oral cancer. The aim of this study was to investigate the relationship between the presence of allelic variants Arg194Trp (rs:1799782) and Arg399Gln (rs: 25487) of XRCC1 gene and Thr241Met (rs: 861539) of XRCC3 gene and susceptibility to oral cancer. We also attempted to correlate the frequencies obtained for each of the SNPs to histopathological parameters. METHODS: A case-control study was conducted with genomic DNA from 150 patients with oral squamous cell carcinomas and 150 controls. SNPs were genotyped by RFLP-PCR. RESULTS: The presence of the polymorphic variants of the XRCC1 gene within codon 194 (OR 0.82, 95% CI: 0.44-1.51) and codon 399 (OR 0.94, 95% CI: 0.59-1.50) and within the XRCC3 gene (OR 0.72; 95% CI: 0.45-1.16) were not associated with an increased risk of oral cancer. A combinational analysis of SNPs in both genes indicated no association. The presence of the allelic variants of these two genes had no statistically significant effect on tumor differentiation, lymph node invasion or tumor size. CONCLUSIONS: These results suggest that allelic variants of XRCC1 and XRCC3 are not suitable markers for susceptibility to carcinomas of the oral cavity and are also not related to the later stages of such tumors.
Subject(s)
Alleles , Carcinoma, Squamous Cell/genetics , DNA Repair/genetics , DNA-Binding Proteins/genetics , Genetic Predisposition to Disease/genetics , Genetic Variation/genetics , Mouth Neoplasms/genetics , Adult , Aged , Aged, 80 and over , Arginine/genetics , Carcinoma, Squamous Cell/pathology , Case-Control Studies , Codon/genetics , Female , Gene Frequency/genetics , Genotype , Glutamine/genetics , Humans , Lymphatic Metastasis/genetics , Male , Methionine/genetics , Middle Aged , Mouth Neoplasms/pathology , Polymorphism, Genetic/genetics , Polymorphism, Single Nucleotide/genetics , Risk Factors , Threonine/genetics , Tryptophan/genetics , X-ray Repair Cross Complementing Protein 1 , Young AdultABSTRACT
OBJECTIVE: To quantify the oral cutaneous fistulae after surgery and to identify possible risk factors. METHODS: A retrospective study, interesting patients that were submitted to surgery, with a two years minimum post-operative follow up. The considered variables were: sex, concomitant diseases, tabacco and alcohol use, the anesthesic and pulmonary risks, clinical stage, cervical linphadenectomy, pre or postoperative radiotherapy, accidents during the surgery, wound infection and or hematoma, pulmonary infection, surgery and reconstruction extension. RESULTS: In 159 patients, oral cutaneous fistulae occurred in 48 patients (30,3%): Patients stage T1 in 26,6 %,T2 in 1,8 %,T3 in 16%, and T4 in 40,3% (p=0,0138). The cases N+ developed fistulae in 22.9%, (N2c with 42,8%, (p=0,0136), those with preoperative radiotherapy in 63,6% (p=0,0346) Those with wound infection in 47,3% (p=0,0146), and those with wound deiscense in 53,7 % (p=0,0030). The fistulae rate was of 60% in the regional mucocutaneous flaps reconstruction cases, 39,2% in the myocutaneous ones and 12,5% of microsurgery ones (p=0,0286). CONCLUSION: The general rate of oral cutaneous fistulae was 30,3%. The significant factors were: T stage, cervical linphadenectomy, pre or postoperative radiotherapy, wound infection and deiscense, and the use of flaps.
