Association between interleukin 6 gene polymorphism and human papilloma virus infection in Oral Squamous Cell Carcinoma patients

Abstract

Background: Both HPV and IL 6 gene polymorphism have independently proven their association with OSCC. And we assume that the positivity of both HPV and IL 6 in a patient with OSCC would raise the threshold of patient towards the aggressiveness of the disease.So the aim was to find an association between Human Papilloma Virus and IL 6 gene polymorphism in Oral Squamous Cell Carcinoma patients. Methods and materials: Methodology: This cross-sectional study was conducted at Ziauddin Hospital, Karachi, between Jan 2014 to May 2015. And of consisted a total of 140 oral squamous cell carcinoma patients of 18 y and above (104 males and 36 females). Detailed questionnaire followed by sample collection from each patient was done. These samples were analyzed by polymerase chain reaction for human papilloma virus and IL 6 gene polymorphism was analyzed through restriction fragment length polymorphism. Results: Mean age of the patients was 43.5 ± 11.84 y (range 31–40 y). Most of the patients (45; 32.1%) belonged to the Urdu speaking ethnic group. Pan (87; 62.1%) and Gutka (82; 58.6%) were used by most of the patients. (17;12.1%) patients had history of systemic disease (e.g hypertension, diabetes). And (3021.4%) patients had a positive family history of OSCC. The most common site of OSCC was buccal mucosa (86; 61.4%) in these patients. Majority of the patients (77; 55%) had histologically moderately differentiated OSCC, and more than half of these patients (78; 55.7%) had Group B (stage III & IV) of OSCC. (12;8.6%) out of 140 samples tested positive for human papilloma virus gene and the following pattern was observed for IL 6 gene polymorphism, GG: (46.4%), GC (39.3%), CC (14.3%). A positive association was observed for Group B (stages III & IV) of oral squamous cell carcinoma with IL 6 genotypes: GC heterozygote (OR = 3.819, 95% CI = 1.782-8.183, p = 0.001) and CC homozygote (OR = 6.833, 95% CI = 2.046-22.822, p = 0.002), and also a strong positive association was found between human papilloma virus and CC homozygote genotype (OR = 21.333, 95% CI = 2.318-196.311, p = 0.007). Conclusion: Human papilloma virus association with IL 6 gene polymorphism in oral squamous cell carcinoma patients suggests rapid and aggressive progress of oral carcinogenesis.