Caspase-3 activity as a prognostic factor in colorectal carcinoma

Several techniques to determine apoptotic frequencies in tumors have been d escribed. In this study, we report that biochemical detection of enzymatic caspase-3 activity is a simple and quantitative technique to measure apopto sis in colorectal tumor cells. The relevance of the level of apoptosis in c olorectal cancer for the clinical course remains unclear. Therefore, we stu died the correlation between caspase-3 activity and prognosis of the diseas e in relation to different factors known to be involved in apoptosis induct ion. High caspase-3 activity significantly correlated with a higher risk of recurrence and was preferentially found in tumors of the right side of the ! colon. No correlation was detected between high caspase-3 activity and al tered protein expression of p53, beta -catenin, or proteins of mismatched r epair genes. This indicates that high caspase-3 activity has no evident cor relation with the genetic Wnt-signaling or the mismatch repair mutational p athways. The caspase-3 activity significantly correlated with CD57(+) tumor infiltrating cells. Therefore, high caspase-3 activity in right-sided tumo rs might be induced by a specific lymphocytic reaction.