E-CADHERIN EXPRESSION IN COLORECTAL-CANCER - AN IMMUNOCYTOCHEMICAL AND INSITU HYBRIDIZATION STUDY

Expression of the epithelial-specific adhesion molecule E-cadherin has been assessed in paraffin-embedded tissue from a series of 72 colorec tal carcinomas. Using immunocytochemistry and in situ hybridization it was found that E-cadherin expression was related inversely to tumor d ifferentiation. Out of 44 well- and moderatelY differentiated tumors, 36 expressed good positivity, whereas 24 of 28 poorly differentiated t umors were E-cadherin-negative. Classification by Dukes stage revealed a highly significant difference (P much less than 0.001) between A an d B (32 positive, four negative) and C1 and C2 (seven positive, 29 neg ative) stages in terms of immunoreactivity. Of the 32 lymph node metas tases studied, 20 were negative for E-cadherin expression, as were sev en of eight liver metastases. These results indicate that the down-reg ulation of E-cadherin levels in vivo is associated with the dedifferen tiation, progression, and metastasis of colorectal cancer.