DPC4基因转染对胰腺癌细胞化疗敏感性的影响

目的 运用基因转染技术,观察DPC4基因转染对胰腺癌细胞化疗敏感性的影响.方法 构建表达DPC4基因的逆转录病毒载体,转染胰腺癌细胞BxPC-3,获取稳定表达DPC4的子代胰腺癌的细胞株BxPC-3/DPC4.观察5-Fu、吉西他滨(作用72 h)对胰腺癌细胞的抑制作用.同时应用半定量RT-PCR检测胰腺癌细胞内Mdr-1、Chk1基因的表达情况.结果 DPC4基因转染并稳定表达后,BxPC-3细胞对5-Fu、吉西他滨的IC50浓度(72 h)分别降低了1倍左右.同一浓度下,5-Fu、吉西他滨联合DPC4基因转染对BxPC-3细胞的体外抑制作用也明显增强,癌细胞内的Mdr-1、Chk1基因的mRNA表达明显下调.显示单独使用pLXSN/DPC4、5-Fu、吉西他滨,均能在体外抑制胰腺癌细胞的生长,但pLXSN/DPC4联合化疗药物,对癌细胞生长的抑制作用更为明显.结论 DPC4基因转染能够提高胰腺癌细胞对化疗药物的敏感性,其机制可能是通过下调Mdr-1、Chkl的表达来实现的.

Effect of DPC4 gene transfection on chemotherapy sensitivity of pancreatic carcinoma cells

Objective To observe the effect of DPC4 gene transfection on the chemotherapy sensitivity of pancreatic carcinoma cells. Methods The human DPC4 complementary DNA was subcloned to the retroviral vector pLXSN to obtain recombinant pLXSN/DPC4 with direct inserting potential. The daughter cell BxPC-3/DPC4 which had DPC4 stable expression was acquired after the pancreatic carcinoma BxPC-3 cells had been transfected with pLXSN/DPC4. The sensitivity of the carcinoma cells for 5-Fu and gemcitabine was observed. Meanwhile, the mRNA level of Mdr-1 and Chk1was detected by semi-quantity PCR assay. Results The 50% inhibiting concentrations (IC50)of 5-Fuand gemcitabin4e for BxPC-3 (culturing for 72 h) were rather lower than those of BxPC-3/pLXSN and BxPC-3/-cells. Moreover, the semi-quantity PCR assay revealed that the mRNA level of Mdr-1 and Chk1 was down-regulated. These findings indicated that pLXSN/DPC4 vector, 5-Fu and gemcitabine could inhibit the growth of pancreatic cancer cells. The combined therapy with pLXSN/DPC4 vector and chemotherapeutic drugs could further inhibit the growth of cancer cells. Conclusion The DPC4 gene transfection could enhance the sensitivity of pancreatic cells to chemotherapy, which may be realized through the down-regulation of Mdr-1 and Chk1 gene expression.