Molecular studies into the role of CD44 variants in metastasis in gastric cancer

CD44, an integral membrane glycoprotein expressed by many cell types, serve s as the principal transmembrane hyaluronate receptor and might be a determ inant of metastatic and invasive behaviour in carcinomas. The generation of CD44 splice variants might be linked closely with gastric carcinoma tumori genesis and differentiation. Some studies have reported that the magnitude of CD44 variant synthesis at the protein level correlates with lymph node m etastasis. A number of studies have examined the possible mechanism of invo lvement of the CD44 variant in tumour metastasis. Most studies have reporte d that the regulation of CD44 binding to hyaluronate results from glycosyla tion of variably spliced exons. Direct hyaluronate binding studies of CD44 V4-V7 isoforms transfected into the human gastric carcinoma cell line, SC-M 1, have indicated that the V4-V7 isoforms themselves, in addition to glycos ylation, can alter hyaluronate binding.