反义缺氧诱导因子-1α对胰腺癌细胞BxPC-3化疗敏感性的影响

目的： 观察反义缺氧诱导因子-1α(HIF-1α)对胰腺癌细胞BxPC-3化疗敏感性的影响。方法：实验分组：（1）缺氧条件下(0.5% O2)体外培养4h，未转染反义HIF-1α质粒的BxPC-3细胞设为缺氧对照组；（2）常氧条件下体外培养，未转染反义HIF-1α质粒的BxPC-3 细胞设为常氧对照组；（3）缺氧条件下(0.5% O2)体外培养4h，稳定转染反义HIF-1α质粒的BxPC-3细胞设为实验组。采用逆转录聚合酶链反应 (RT-PCR)和免疫印迹(Western Blot)检测各组的HIF-1α和survivin表达情况。 流式细胞术和MTT比色法检测不同剂量的化疗药物(5-氟尿嘧啶、阿霉素、吉西他宾)对各组的凋亡率和生长抑制率的影响。 结果：实验组HIF-1α和survivin的表达明显降低 (P<0.05)，与对照组相比，实验组的凋亡率、抑制率与剂量成正比，高剂量引起高抑制(P<0.05)。 结论：反义HIF-1α可能通过阻断survivin的表达而增强胰腺癌对化疗的敏感性。据此可望通过阻断HIF-1α的表达为胰腺癌基因治疗提供一种新途径。

Effect of gene transfer of antisense hypoxia inducible factor-1α on chemosensitivity of human pancreatic cancer cell line BxPC-3

Abstract:Objective：To observe the effect of antisense hypoxia inducible factor-1α(HIF-1α) on chemosensitivity of human pancreatic cancer cell line BxPC-3 under hypoxia. Methods：BxPC-3 cells were divided into 3 groups:(1)BxPC-3 cells were non-transfected with antisense HIF-1α plasmid and exposed to 0.5% O2 for 4hr (hypoxia control); (2)normoxic BxPC-3 cells were non-transfected with antisense HIF-1α plasmid (normoxia control); (3)BxPC-3 cells were transfected with antisense HIF-1α plasmid and exposed to 0.5% O2 for 4hr (experimental group). Expression of HIF-1α and survivin was detected by RT-PCR and Western Blot. Growth inhibition rates and apoptosis rates of BxPC-3 cells under different dosages of chemotherapeutic agents (5-fluorouracil, doxorubicin and gemcitabine) were measured by MTT colorimetric assay and flow cytometry (FCM). Results：Expression of HIF-1α was obviously down-regulated and at the same time survivin expression was markedly down-regulated in experimental group (P<0.05). Higher dosages (100 mg/L, 200 mg/L and 400 mg/L of 5-fluorouracil, 0.05 mg/L, 0.075 mg/L and 0.1 mg/L of doxorubicin, 10-9 mol/L, 10-8 mol/L and 10-7 mol/L of gemcitabine) caused a greater increase of inhibition in experimental group than in hypoxia control (P<0.05). Conclusions：The results demonstrate that antisense HIF-1α inhibits expression of survivin and enhances chemosensitivity of human pancreatic cancer cell BxPC-3. Blocking HIF-1α in pancreatic cancer cells may offer an avenue for gene therapy.