Prevalence of human papillomavirus genotypes among egyptian patients with cancer bladder

Human Papillomavirus (HPV) infection has been recognized as the main etiologic factor in the development of various cancers including penile, vulval, oropharyngeal, cervical and bladder cancers. The aim of this study was to identify the genotypes of HPV associated with cancer bladder in Egyptian patients and to evaluate the sensitivity of type-specific PCR (TSPCR) and DNA-based liquid-crystal display (LCD)-Array kit for diagnosis and genotyping of HPV infection in these patients. Method: A total of 55 patients with bladder cancer were conducted in this study. Forty-two (76.4%) patients had transitional cell carcinoma (TCC) (24 patients associated with schistosomiasis and 18 patients without) and 13 (23%) patients with squamous cell carcinoma (sqCC) (12 patients associated with schistosomiasis and one patient without). Samples included fresh bladder cancer biopsies, urine and sera. HPV-DNA was detected in the specimens by PCR using GP5/GP6 and MY09/MY11 primer sets. HPV genotyping was performed using TSPCR and LCD-Array kit. Results: HPV-DNA was detected in 23.6% (13/55) of the tissue specimens by PCR using the general primer set GP5/GP6 and was detected in 9% (5/55) using MY09/MY11 primer sets. All MY09/MY11 positive samples were also positive for GP5/GP6. There was a statistical significant difference between the number of positive cases detected using GP5/GP6 compared to the number of positive cases using MY09/MY11 (p value < 0.01). HPV-DNA was not detected in serum and urine using GP5/GP6 primers. Schistosomiasis was associated with 69.2% (9/13) of HPV-DNA infected patients. HPV-16 and HPV-18 were detected in tissue specimens by TSPCR in 30.7% (4/13) and 7.7% (1/13) respectively and one case (7.7%) was HPV16-18 mixed infection. LCD-array kit detected 5/13 (38.4%) cases HPV-6, 3/13 (23.0%) cases HPV-16, 1/13 (7.7%) HPV-33 and 4/13 (30.8%) mixed infections. The results obtained by LCD-array kit were similar to that obtained by PCR using MY09/MY11 and GP5/ GP6 primer sets with 100% sensitivity, specificity, PPV and NPV. Conclusions: TSPCR and microarray were sensitive and specific techniques for detection and genotyping of HPV infections in bladder cancer tissue. They provided a useful technology to study the substantial genetic heterogeneity of HPVs and the clinical relevance of specific subtypes. So, the application of HPV DNA detection in combination with genotyping is considered a corner-stone step for the prediction of the natural history of HPV infection and for better understanding of epidemiological phenomena and vaccine preparation modification.