Loss of Cell Differentiation in HPV-Associated Bladder Cancer

Medical histories of 101 urothelial bladder cancer patients were compared with the results of morphological analysis and biomolecular detection of human papilloma viruses (HPV) in the tumor specimens. DNA of HPV16 (the major type of virus responsible for appearance of cervical carcinoma) was detected in 38 specimens, while mRNA of E6 and E7 oncogenes and E7 oncoprotein of HPV16 were observed in 13 specimens. HPV-positive bladder cancer was characterized by higher degree of cell anaplasia than HPV-negative cancer; in the primary bladder tumor, HPV was detected more often than in recurrent bladder cancer. These data attest to involvement of HPV16 in the genesis of bladder cancer. No correlations of HPV status of bladder tumor with patient's sex, age, and invasion into the muscle layer were revealed.