Coexpression of matrilysin and laminin-5 gamma2 chain may contribute to tumor cell migration in colorectal carcinomas.

We attempted to examine the correlation between matrilysin and laminin-5 gamma2 chain expression with reference to the number of dedifferentiation units along the entire invasive front (tumor budding). Immunostaining for hMMP-7 and laminin-5 gamma2 chain was performed in 50 T1 colorectal carcinomas, and immunoreactivity was evaluated at the invasive front of the tumor. On hematoxylin-eosin sections, the number of tumor budding was counted. The localization of matrilysin tended to be widespread compared with that of laminin-5 gamma2 chain. Matrilysin and laminin-5 gamma2 chain expression were positive in 28 (56%) and 15 (30%) tumors respectively. There was a significant correlation between matrilysin and laminin-5 gamma2 chain expression (P = 0.02). Matrilysin(+)/laminin-5 gamma2 chain(+) tumors had a significantly greater amount of tumor budding than matrilysin(-)/laminin-5 gamma2 chain(-) tumors (P = 0.003) or matrilysin(+)/laminin-5 gamma2 chain(-) tumors (P = 0.03). In conclusions, coexpression of matrilysin and laminin-5 gamma2 chain may contribute to tumor cell migration in colorectal carcinomas.