胰腺癌组织中程序性细胞死亡因子4与细胞色素C的关系

Relationship between the expression of cytochrome c and programmed cell death 4 in pancreatic cancer

目的研究胰腺癌组织中程序性细胞死亡因子4（PDCD4）与细胞色素C（Cyt c）表达的关系，探讨PDCD4诱导胰腺癌细胞凋亡的途径。方法收集1990年至2002年中国医科大学附属一院69例手术切除的胰腺癌标本，采用免疫组织化学方法检测胰腺癌石蜡标本中Cyt c的表达，同时采用Western blot方法检测其中8例冷冻保存的新鲜胰腺癌及正常胰腺组织中Cytc的表达情况，结合前期PDCD4在胰腺癌组织中的表达结果采用配对t检验和χ^2检验进行分析。结果同正常胰腺组织比较，胰腺癌组织Cytc表达明显下降。69例胰腺癌组织中，28例（41％）患者Cytc呈阳性表达；41例（59％）患者Cytc呈阴性表达。PDCD4蛋白呈阳性表达的患者中Cytc亦多呈阳性表达；Cytc蛋白呈阴性表达患者中PDCD4表达多呈阴性，两者表达有关（χ^2=10．52，P〈0．05）。结论胰腺癌组织中PDCD4和Cytc表达密切相关，PDCD4可能通过线粒体途径引起Cytc释放，启动凋亡程序，诱导细胞凋亡。

Objective To study the relationship between the expression of cytochrome c （Cyt c） and programmed cell death 4 （PDCD4） in pancreatic cancer, and investigate the pathway of PDCD4 inducing the apoptosis of pancreatic cancer cells. Methods Pancreatic cancer specimens from 69 patients who received pancreatic resection from 1990 to 2002 in First Affiliated Hospital of China Medical University were collected. The expression of Cyt c in the 69 paraffin specimens of pancreatic cancer was detected by immunohistochemistry, and the expression of Cyt c in 8 samples of cold-preserved fresh pancreatic cancer and normal pancreatic tissues were detected by Western blot. The expression of PDCD4 and Cyt c in pancreatic cancer was analyzed by paired t test and chi-square test. Results Compared with normal pancreatic tissues, the expression of Cyt c in pancreatic cancer was significantly decreased. The positive expression rate of Cyt e in 69 samples of pancreatic cancer was 41% （28/69）. The expression of Cyt c was positive in most patients with positive expression of PDCD4, and the expression of PDCD4 was negative in most patients with negative expression of Cyt c. The expression of PDCD4 and Cyt c was closely correlated with each other （χ^2 = 10.52, P 〈 0.05 ）. Conclusions There is a close relationship between the expression of PDCD4 and Cyt c in pancreatic cancer. PDCD4 may induce the apoptosis of pancreatic cancer cells through mitochondrial pathway.