CD44 with variant exons 8-10 in colorectal tumors.

Using a fusion protein encoded by variant exon (v) 8-10 of CD44, a monoclonal antibody (mAb) 44-1V reactive with v9 product was generated. Western immunoblots and reverse transcriptase-polymerase chain reaction/Southern blot revealed that a 130 kilodalton component containing v8-10 products was specifically expressed in colorectal and gastric cancer cell lines. Immunohistological examination of 179 pairs of colorectal cancer and normal tissues revealed that about 47% of cancers expressed the CD44 variant (CD44v8-10), and its expression correlated with hematogenous and lymph node metastasis. These findings suggest the usefulness of CD44v8-10 in the prediction of colorectal cancer metastasis.