Objective To investigate the mechanism of the resistance of pancreatic cancer cells to tumor necrosis factor related apoptosis inducing ligand (TRAIL)mediated apoptosis. MethodsThe expression of TRAIL receptor-4 (TRAIL-R4) in normal pancreas tissue and pancreatic cancer was analyzed by using Northern blotting, Western blotting and immunohistochemistry.ResultsTRAIL-R4 mRNA and protein were expressed at moderate to high levels in human pancreatic cancer, but demonstrated weak to negative in the normal pancreas. Moreover, pancreatic cancer cells showed b TRAIL-R4 immunostaining throughout the tumor mass. Conclusion TRAIL-R4 levels are significantly different in pancreatic cancer in comparison to the normal pancreas. These findings give new insights into the resistance mechanisms of pancreatic cancer cells towards TRAILmediated apoptosis.
Objective To investigate the expressions of tumor necrosis factor related apoptosis inducing ligand （TRAIL） and its receptors (DR4, DcR1) in human rectal cancer tissues and normal rectal tissues. MethodsThe expressions of TRAIL and its receptors (DR4, DcR1) in 31 cases of human rectal cancer tissues and 20 cases of normal rectal tissues were detected by immunohistochemical staining. ResultsThe positive expression rates of TRAIL, DR4 and DcR1 （32.26%， 29.03%， 0） were lower than those of normal rectal tissues （55.00%， 70.00%， 65.00%）, the difference was statistically significant(P=0.015， P=0.000， P=0.000). There were no relation between the expressions of TRAIL, DR4 and DcR1 and clinicopathologic characteristics (Pgt;0.05). ConclusionThe expressions of TRAIL and its receptors (DR4, DcR1) in human rectal cancer tissues were lower than those of normal rectal tissues, which may suggest that the apoptotic effect induced by the interaction between TRAIL and its receptors has attenuated in human rectal cancer.