CD44 expression in cervical intraepithelial neoplasia (CIN) and carcinoma

Background: The expression of the CD44 gene is markedly changed in many neoplastic tissues. The identification of tumor-specific CD44 expression patterns may aid tumor diagnosis. Methods and Results: The transcription and translation of the CD44 gene were analyzed by reverse transcription polymerase chain reaction (RT-PCR), in situ hybridization and by immunohistochemistry. Samples were obtained from 24 normal and 24 neoplastic or malignant human cervical tissues. Southern blot hybridization analysis of RT-PCR products revealed an increase in the size and number of CD44 standard and variant transcripts in malignant cervical tissues compared with corresponding normal tissues. Misprocessing of mRNA was indicated in cervical carcinoma cells by the retention of intronic sequences. Multiple CD44 mRNA and protein isoforms were present throughout carcinoma tissues, whereas localization was restricted to the basal epithelium in normal cervical tissue. Analysis of desquamated cervical cells from cases of cervical intraepithelial neoplasia stages I-III showed progressively deranged patterns of CD44 expression, with more alterations being detected in the more advanced stages. Conclusions: Marked alterations in CD44 expression occur in cervical tissues during progression to malignancy. CD44 expression analysis could aid the early diagnosis of cervical malignancy using minimally invasive methods.