Splice variants of the cell surface glycoprotein CD44 (CD44v) have been implicated in the progression of various human tumors. In the present study, we have examined the expression pattern of a CD44v epitope encoded by the adjacent variant exons v7 and v8 during human c:ervical carcinogenesis. While only I / I I normal cervical squamaous epithelia was positive for this epitope by immunohistocheimistry, 4/2 I samples of lowgrade squamous intra-epithelial lesions (LSIL), 17/35 samples of high-grade squamous intra-epithelial lesions (HSIL), I I / I 2 samples of the HSIL subgroup of carcinoma in situ and I7/ I 7 cases of invasive cervical carcinoma showed CD44v7/8 epitope expression. In addition to CD44 variant expression, we have analyzed 67 lesions for the presence of HPV16/ 18-DNA using PCR. Most of the samples expressing the v7/8 epitope were also HPVI6-positive (29/32), whereas only 17/35 of the v7/8negative samples were HPV 16-positive. HPVl8 DNA was found in only one invasive carcinoma. Our data suggest that high-risk HPV infection may precede CD44v7/8 expression and that the number of samples expressing the! CD44 v7/8 epitope increases during carcinogenesis and reachles nearly 100% at the carcinoma in situ stage. This CD44 epitope could, therefore, serve as a diagnostic marker of cervical sqiiamous cell carcinomas and as a Dossible tareet for CD44v7/8 eoitooe-directed theraDies. 0.1 996 Wilq-Eiss. Inc.