Bax protein may influence the invasion of colorectal cancer.

Aim: To evaluate the expression of Bcl-xL, Bak, and Bax proteins in correlation with particular clinico-histopathological parameters, including tumor invasion front, in patients with colorectal cancer.
Methods: The expression of these proteins was evaluated with the use of the immunohistochemical method in 50 primary tumors.
Results: According to observations, a low expression of Bax and Bak proteins is related to the localization of the tumor in the rectum (P < 0.05 and P < 0.05 respectively), which may explain an increased incidence of colorectal cancer in this area. A positive expression of Bax protein also correlates with the presence of cancer cell infiltration to lymph and blood vessels (P < 0.05), which may suggest the participation of this protein in the early stages of colorectal cancer progression. Moreover, a positive expression of Bcl-xL protein correlated with a positive expression of Bak protein. This may suggest a greater participation of Bcl-xL protein in the inhibition of the proapoptotic Bak protein, but not the Bax protein.
Conclusion: Bax protein is probably very significant in the cancerogenesis mechanism in the large intestine.