肝癌多药耐药产生与低糖环境的关系

目的探讨局部微环境低糖与肝细胞癌多药耐药性(MDR)产生的关系及影响机制。方法低糖培养HepG2细胞,应用流式细胞术Annexin V/PI法检测低糖培养的细胞在化疗药物5-氟脲嘧啶(5-Fu)作用后的凋亡情况,分别应用荧光定量聚合酶链反应(PCR)技术和Western blot技术检测低糖培养后HepG2细胞内多药耐药相关基因mdr1、MRP1、LRP的mRNA和蛋白水平的表达。结果在低糖环境下生长时间越长的HepG2细胞对5-Fu的抵抗越强,而且随着低糖培养时间的增加,5-Fu诱导的HepG2细胞的凋亡高峰延迟。低糖培养的HepG2细胞内多药耐药相关基因mdr1、MRP1、LRP在mRNA和蛋白水平的表达随低糖培养时间的延长而升高,以LRP的改变最为显著。结论肝癌生长微环境葡萄糖耐量不足也是肝癌产生MDR的原因之一。低糖可通过上调一组多药耐药相关基因的表达而诱导肝癌的多药耐药性。

Glucose deprivation and formation of multidrug resistance of hepatocellular carcinoma

Objective To investigate the influence of glucose deprivation on the formation of mul-tidrug resistance of hepatocellular carcinoma and to clarify its mechanism. Methods HepG2 cells were exposed to glucose-free DMEM medium for 24,48 and 72 h respectively. Apoptotic index of the HepG2 cells exposed to low glucose was analyzed by Annexin/PI method using flow cytometry after administration of 5-Fu. Real-time fluorescent quantitative PCR and Western-blot technique were respectively used to detect the expression of mdr1 , MRP1 and LRP at mRNA and protein levels. Results The resistance of HepG2 cells to 5-Fu was gradually enhanced and the apoptosis peak was delayed as the exposed time extended under the surroundings of low glucose. In HepG2 cells subjected to low glucose, the expression of mdr1, MRP1 and LRP at mRNA and protein level was increased gradually as the exposed time prolonged, most notably in LRP. Conclusion Glucose starvation is one of the causes that facilitate the development of MDR of HCC. Low glucose induces MDR phenotype of HCC by upregulating the expression of a cohort of the MDR related genes.