| 摘要 |
The present invention provides a novel and improved method for the diagnosis, and continuing assessment, of squamous cell carcinoma (SCC). The protein encoded by a rabbit cDNA termed SQ10 is shown to be a molecular marker of squamous cell differentiation. By immunoblotting with antibodies raised against a 22 residue SQ10 synthetic peptide, SQ10 is shown not to be present in undifferentiated cells. SQ10 expression is up-regulated during the differentiation process and inhibited by retinoids. DNA and amino acid homologies between SQ10 and various preprorelaxin proteins allowed SQ10 to be identified as a preprorelaxin-like molecule. The SQ10 relaxin-like protein is secreted from squamous epithelial cells, and as such represents the first molecular marker of squamous cell differentiation that can be detected in body fluids. The rabbit SQ10-derived peptide was found to have a counterpart in human preprorelaxin, with the sequence MSTWSKRSLSQEDAPQTPRPV. Antibodies raised to a peptide of this sequence are also specific differentiated squamous cells. Such antibodies can be used to detect the presence of preprorelaxin-related molecules in normal and malignant squamous cells and in human biological samples and, importantly, in tissue fluids, and thus can be used in a diagnostic test for SCC. |
