HPV infection and microsatellite instability in squamous lesions of the uterine cervix

The role of human papillomavirus (HPV) in the development of squamous lesio ns of the uterine cervix has been clearly established but other factors cou ld be involved in cervical tumorigenesis, arch as microsatellite instabilit y (MI). The aim of the present study was to analyze the relationship betwee n HPV infection and MI. Thirty-two cervical samples were analyzed: II low-g rade CIN (LCIN), 18 high-grade CIN (HCIN) and 3 carcinomas. DNA was extract ed from formalin-fixed, paraffin embedded tissue for PCR study with HPV 6/1 1, 16, 18 and 7 microsatellite primers: D2S123 (cr2), MFD39 (cr8), 635-636 (cr15q), MFD67 (cr1), D11S905 (cr11), SCZD1 (cr5q) and DM (cr19). HPV was d etected in 82% of LCIN (16 and 18 types in 64% of cases) and in 33% of HCIN (16 type in 22% of cases). The difference between LCIN and HCIN was statis tically significant (p=0.014), in particular for 16 and 18 HPV types (p=0.0 33). Forty-seven per cent of total cases showed MI with no move than 3 diff erent loci per case: 27% of LSIL, 61% of HCIN and 33% of carcinomas (not st atistically significant). In 45% of HCIN cases there were both MI and HPV. In conclusion, cervical carcinoma is linked to HPV infection but MI could a lso be involved in cervical tumorigenesis.