E4 expression of human papillomavirus in cervical samples with different cytology categories.

In some circumstances, infection with human papillomavirus (HPV), especially HPV type 16 (HPV16), progresses to cervical cancer. Viral E4 expression reflects viral replication and translation and its presence may rule out a latent infectious stage. Twenty cervical cytology samples with known HPV 16 infection of each cytological category namely, negative for intraepithelial lesion (NIL), low grade squamous intraepithelial lesion (LSIL), high grade squamous intraepithelial lesion (HSIL) and squamous carcinoma (SCC) were investigated by single-step quantitative RT PCR for HPV 16 E4 mRNA, which was not found in any NIL sample but in all LSIL and HSIL samples. Thus, E4 expression assay should be useful for determining precancerous states and may be suitable as an adjunct in cervical HPV testing.

Entire genome characterization of human papillomavirus type 16 from infected Thai women with different cytological findings.

Global prevalence of human papillomavirus type 16 (HPV16) exceeds that of other types. This project has been aimed at attaining basic molecular knowledge of HPV16 by sequencing the whole genome of HPV16 isolated from Thai women at various clinical stages of disease progression. Our group analyzed seven samples of HPV16 in infected women ranging from normal to cervical cancer and discovered two critical non-synonymous changes within the coding region converting the E2-219P prototype to E2-219T in cervical cancer and the L2-269S prototype to L2-269D in CIN III, respectively. Phylogenetic analysis based on the whole genome with special emphasis on the genes E2, E6, L1, and L2 showed the Thai samples to be more closely related to the European than the non-European strains. The vaccine strain's L1 polypeptides showed close relationship to our samples. The results provide basic data for future research on cervical cancer pathogenesis and representative data of HPV16 genome in Southeast Asia.