The major E6/E7 transcript of HPV-16 in exfoliated cells from cervical neoplasia patients

HPV-16 is implicated in the development of progressive cervical neoplasia, and E6 and E7 proteins of this virus play important roles in its oncogenic activity. Reverse transcriptase-nested-polymerase chain reaction (RT-nested PCR) method was applied to detect the major transcript (E6*I/E7) from E6/E7 ORFs of HPV-16 in the exfoliated cervical and vaginal cells from cervical neoplasia patients. The incidence of the E6*I/E7 transcript was proportional to the class of cytologic diagnosis. Further analysis revealed that the incidence of the E6*I/E7 transcript in Pap smears of class I or II was 5/28 (18%) patients who had previously been diagnosed as having cervical neoplasia but was 1/37 (3%) patients who had never been diagnosed (P < 0.05). These findings suggest that some patients followed up for cervical neoplasia were infected with transcriptionally active HPVs even when their Pap smears were negative. In addition, the E6*I/E7 transcript could not be detected after surgical treatment in any of the cases that were able to be followed up. The E6*I/E7 transcript in the exfoliated cells may prove valuable for epidemiological studies of the pathogenesis of HPV infection.