The antibody response to HPV proteins and the genomic state of HPVs in patients with cervical cancer

Human papillomavirus (HPV) DNAs are often found to be integrated into the h uman genome in high-grade cervical intraepithelial neoplasia (CIN) as well as in invasive cervical cancers. Investigation of the relationship between the genomic status of specific HPV genes and their antibody responses to th e virus-like particles (VLPs) of HPV-16 L1/L2 proteins and the in vitro tra nslated HPV-16 E6 and E7 proteins may help to illustrate the mechanism of H PV-related cervical carcinogenesis and host immune response. Cervical cance r tissues obtained from 39 patients were studied to evaluate the physical s tatus of HPV genes by Southern blotting, DNA-PCR, and RT-PCR of E2. The ant ibody response against the HPV-16 L1/L2 VLPs of serum specimens were tested by ELISA and the antibody response against the HPV-16 E6 and E7 proteins w ere tested by radioimmunoprecipitation assay (RIPA), respectively. Integrat ed forms of HPV-16 DNA were found in 23 of the 38 patients (60.5%). The HPV -16 positive cervical cancer patients showed a significantly higher prevale nce rate (39.5%; 15/38) of antibodies to HPV-16 L1/L2 VLPs than that of the control group (8.7%; 2/28) (P < 0.05). Antibodies to HPV-16 L1/L2 VLPs wer e more commonly detectable in cervical cancer patients having the episomal form of HPV-16 DNA (pure episomal and mixed forms) (60%; 9/15) than in thos e who had only the integrated forms of HPV-16 DNA (26.1%; 6/23) (P < 0.05). Antibodies to E6 and E7 proteins were positive in 36.8% (14/38) and 50% (1 9/38) of the patients with HPV-16 positive cervical cancer, respectively. T hese were significantly higher than the positive rates for the control grou p (8.3% and 2.8%) (P < 0.05). The differences between sero-reactivities to E6 and E7 proteins in the patients with episomal forms of HPV-16 DNA and th ose with integrated forms of HPV-16 DNA were not statistically significant (P > 0.05). Integrated forms of HPV-16 DNA were prevalent in most patients with cervical cancer in Korea. Antibodies to HPV-16 L1/L2 VLPs, in vitro tr anslated HPV-16 E6 and E7 proteins, appeared in a significantly larger prop ortion of the HPV-associated cervical cancer patients than in the controls. Antibodies to HPV-16 L1/L2 VLPs were more often detected in cervical cance r patients having the episomal form of HPV-16 DNA than in those having only integrated forms of HPV-16 DNA. Antibody responses to HPV-16 E6 and E7 pro teins were not influenced by the different viral states.