Overexpression of Twist in colorectal adenocarcinoma

ABSTRACT Background and aim: Twist, a basic helix‐loop‐helix (bHLH) transcription factor, is a master regulator of gastrulation and mesoderm specification. Twist has now been characterized as a newly found epithelial‐mesenchymal transition (EMT)‐inducer and has been shown to be involved in tumor invasiveness and metastasis. The aim of the present study was to examine the pattern of Twist expression in colorectal adenocarcinoma (CRA) and to compare the expression of Twist and E‐cadherin as determined by immunohistochemical analysis. Methods: A semiquantitative scoring system was applied based on the intensity and the extent of positive expression in cancer cells. Results: Twist was not detected in non‐neoplastic mucosa, but immunoreactivity was evident in 86.2% of CRA. Expression of Twist was significantly associated with tumor invasion (P= 0.001) and differentiation (P= 0.003), and showed inverse correlation with E‐caherin expression (P= 0.045). Twist expression did not influence overall survival. Conclusions: We demonstrated, for the first time, that Twist is up‐regulated in CRA. These results demonstrated that a positive role of Twist in tumor invasion in CRA, and inverse correlation of Twist and E‐cadherin expression suggest that Twist may play some role in the EMT by inhibition of E‐cadherin activity.