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<b>Objective</b> To investigate LC3B-II and active caspase-3 expression in human colorectal cancer to elucidate the role of autophagy, and to explore the relationship of autophagy with apoptosis in human colorectal cancer.<br><b>Methods</b> LC3B expression was detected by immunohistochemistry in 53 human colorectal cancer tissues and 20 normal colon tissues. The protein levels of LC3B-II and active caspase-3 were also determined by Western blot analysis in 23 human colorectal cancer tissues and 10 normal colon tissues.<br><b>Results</b> LC3B was expressed both in cancer cells and normal epithelial cells. LC3B expression in the peripheral area of cancer tissues was correlated with several clinicopathological factors, including tumor differentiation (<i>P</i>=0.002), growth pattern of the tumor margin (<i>P</i>=0.028), pN (<i>P</i>=0.002), pStage (<i>P</i>=0.032), as well as vessel and nerve plexus invasion (<i>P</i>=0.002). The protein level of LC3B-II in cancer tissue was significantly higher than in normal tissue (<i>P</i>=0.038), but the expression of active forms of procaspase-3 in cancer tissue was lower (<i>P</i>=0.041). There was a statistically significant positive correlation between the expression levels of LC3B-II and the active forms of procaspase-3 (<i>r</i>=0.537, <i>P</i>=0.008).<br><b>Conclusions</b> Autophagy has a prosurvival role in human colorectal cancer. Autophagy enhances the aggressiveness of colorectal cancer cells and their ability to adapt to apoptotic stimulus.