• Asian Pacific Journal of Cancer Prevention
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• 제15권10호
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• pp.4325-4329
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• 2014

Background: The expatriate population in Qatar largely comprises workers from the Indian subcontinent which has a very high rate of oral malignancy. Social and cultural habits and as well premalignant risk factors in this population remain prevalent even after migration. Materials and Methods: This cross sectional study assessed the prevalence of risk factors and occurrence of oral precancerous lesions in a low income group expatriate community from the Indian subcontinent residing in Qatar. Results: Among the 3,946 participants screened for oral premalignant lesions 24.3% (958) were smokers and 4.3 % (169) were pan chewers while 6.3% (248) were users of both smoked and smokeless forms of tobacco. Significantly higher proportion of industrial laborers (49.9%) followed by drivers (24.1%) were found to be smokers (p=0.001). The prevalence of white lesions was higher in smokers versus non-smokers 3.5% versus 2.3% (p=0.111), however this difference was statistically non-significant. Red and white lesions were highly significant (i.e. 1.2 % and 10.9% respectively) in the subjects with pan chewing and smoking habits (p=0.001). A significant proportion (8.9%) of the subjects with pan chewing habit showed evidence of oral precancerous lesions (p=0.001). Conclusions: Even though smoking and pan chewing were two significant risk factors detected in this population, their prevalence and occurrence of premalignant lesions are low as compared to the studies conducted in their home countries.

• Asian Pacific Journal of Cancer Prevention
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• 제17권6호
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• pp.2811-2819
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• 2016

Multiple genetic and environmental factors have been reported to play key role in the development of nasopharyngeal carcinoma (NPC). Here, we investigated interactions of XRCC1 Arg399Gln and XRCC2 Arg188His polymorphisms and environmental factors in modulating susceptibility to NPC in Northeast India. One-hundred NPC patients, 90 first-degree relatives of patients and 120 controls were enrolled in the study. XRCC1 Arg399Gln and XRCC2 Arg188His polymorphisms were determined using PCR-RFLP, and the results were confirmed by DNA sequencing. Logistic regression (LR) and multifactor dimensionality reduction (MDR) approaches were applied for statistical analysis. The XRCC1 Gln/Gln genotype showed increased risk (OR=2.76; P<0.024) of NPC. However, individuals with both XRCC1 and XRCC2 polymorphic variants had 3.2 fold elevated risk (P<0.041). An enhanced risk of NPC was also observed in smoked meat (OR=4.07; P=0.004) and fermented fish consumers (OR=4.34, P=0.001), and tobacco-betel quid chewers (OR=7.00; P=0.0001) carrying XRCC1 polymorphic variants. However, smokers carrying defective XRCC1 gene showed the highest risk (OR = 7.47; P<0.0001). On MDR analysis, the best model for NPC risk was the five-factor model combination of XRCC1 variant genotype, fermented fish, smoked meat, smoking and chewing (CVC=10/10; TBA=0.636; P<0.0001); whereas in interaction entropy graphs, smoked meat and tobacco chewing showed synergistic interactions with XRCC1. These findings suggest that interaction of genetic and environmental factors might increase susceptibility to NPC in Northeast Indian populations.