ABSENCE OF HUMAN PAPILLOMAVIRUS-16 AND PAPILLOMAVIRUS-18 DNA AND EPSTEIN-BARR-VIRUS DNA IN ESOPHAGEAL SQUAMOUS-CELL CARCINOMA

To elucidate the association of human papillomavirus (HPV) and Epstein -Barr virus (EBV) with carcinogenesis of the esophagus, 41 surgically resected specimens and 12 cell lines of esophageal squamous cell carci noma were examined for the presence of HPV DNA and EBV DNA by polymera se chain reaction using primers for the E6 regions of HPV-16 and -18 a nd for the EBNA 1 region of EBV, We designed the reaction condition to amplify HPV and EBV DNA specifically and detected by gel electrophore sis, In ethidium bromide staining, no band was detected either for the HPV E6 region or for the EBV EBNA 1 gene in any of the surgically res ected specimens and the cell lines, although the HPV sequence was dete ctable by Southern blot hybridization, which is a more sensitive detec tion method than staining; three out of 41 surgically resected specime ns were positive for HPV-18 by Southern blot hybridization of polymera se chain reaction products, However, the number of viral genomes has b een estimated as lower than 1 x 10(-3) copies per cell based on the in tensity of the hybridization signals, Moreover, the DNA samples extrac ted from the corresponding non-cancerous esophageal mucosa were also p ositive for HPV-18, and the intensities of the hybridization signals w ere almost the same as those of the tumors, The results of our study i ndicate that HPV-16, HPV-18 and EBV are not generally associated with esophageal carcinogenesis.