Expression of CD44 splice variants in colorectal cancer

Background The CD44 gene codes fur a family of heavily glycosylated cell surface proteins that have been linked with tumour metastasis. The aim of the study was to analyse the expression of CD44 messenger RNA in colorectal cancer. Methods The expression of CD44 variants 2 and 7 in colorectal tumour samples was compared with that in normal colon and lymphocytes from 59 patients using reverse transcription-polymerase chain reaction followed by blot hybridization with exon-specific probes, and a nested polymerase chain reaction. Results All samples of tumour and metastatic tissue showed complex overexpression of many alternatively spliced products of the CD44 gene. Normal colon, liver and lymphocytes predominantly expressed the standard form of the CD44 molecule (CD44S) with low levels of two or three variants hybridizing to exons v2 and v7. Conclusion Deranged CD44 gene activity in colorectal cancer cells is confirmed. The analysis of CD44 gene expression may provide a promising marker for the early detection of colonic tumours