Expression of mRNA of SCC antigen in squamous cells.

The expression of SCC antigen mRNA was studied by Northern blot analysis and in situ hybridization in human gynecologic tissues. Northern blot analysis revealed that mRNA of SCC antigen was expressed strongly in normal squamous epithelium and columnar epithelium of the uterine cervix, but not in the endometrium, fallopian tube or ovarian tissue. Among gynecologic malignancies, squamous cell carcinoma of the uterine cervix expressed mRNA of SCC antigen, whereas endometrial and ovarian adenocarcinoma were negative. With in situ hybridization, mRNA of SCC antigen is located in the basal and parabasal layers of the normal squamous epithelium, in dysplasia, and also in carcinoma in situ and invasive squamous cell carcinoma. These results confirmed the previous findings by immunohistochemical studies that SCC antigen is closely related to squamous cells, but also raised a new puzzle regarding the different localization of mRNA and its product, SCC antigen, in the normal squamous epithelium.