内科

目的观察抗肿瘤药物长春新碱（Vincristine，VCR）对大鼠胰岛B细胞瘤株INS-1细胞增殖和侵袭的抑制作用和hTERT、Sp1、c-myc表达的影响及其意义，探讨胰岛B细胞瘤的发病机制。方法INS-1分为对照组（不加VCR）和实验组（加入浓度分别为0.008 mg/mL、0.04 mg/mL、0.2 mg/mL、1 mg/mL的VCR）。两组培养24 h后，用MTT比色法检测INS-1细胞的增殖抑制率；用Transwell侵袭试验检测INS-1细胞的侵袭力；RT-PCR检测各组细胞中hTERT、Sp1、c-myc基因的表达。结果实验组抑制率明显高于对照组（P＜0.05）；且随着VCR浓度的增加，INS-1细胞生长抑制率逐渐增加（P＜0.05）；Transwell小室培养细胞24 h后，实验组侵袭到下层膜的细胞数为（63.26±5.12）个，对照组为（150.65±4.02）个（P＜0.01）；与对照组比较，随着时间的延长，实验组的hTERT、Sp1、c-myc mRNA基因在INS-1细胞的表达也逐渐减弱（P均＜0.05）。结论VCR能抑制INS-1细胞增殖和侵袭，可能通过抑制Sp1、c-myc和hTERT表达，从而抑制INS-1的端粒酶活性，进而抑制细胞增殖和降低侵袭能力。

ObjectiveTo observe the effect and significance of the antitumor drugs (Vincristine,VCR) on the proliferation and invasion of rat islet beta tumor cell lines (INS-1 cell),and the expression of hTERT,Sp1and c-myc,and to explore the mechanism of Pancreatic B cell tumor.MethodsThe INS-1 cells were divided into two groups:the control group (no VCR) and the experimental group (concentration of VCR were 0.008 mg/ml,0.04 mg/ml,0.2 mg/ml,1 mg/ml,respectively).After being cultured for 24 hours,MTT assay was used to examine the inhibition rate of the INS-1 proliferation;the invasive ability was tested by Transwell invasion assay.The expressions of hTERT,Sp1 and c-myc in INS-1 cells were detected by RT-PCR.ResultsWith the concentration of antitumor drugs VCR increased,the growth inhibition rate of INS-1 also increased gradually (P＜0.05),and the inhibition rate of the experimental group was significantly higher than that of the control group(P＜0.05);after being cultured by Transwell for 24 hours,the cell number into the submucosa membrane was (150.65±4.02) in the control group,while (63.26±5.12) in the experimental group(P＜0.01);Compared with the control group,as time went by,the expressions of hTERT,Sp1,c-myc mRNA gene in the INS-1 cells of the experimental group weakened gradually (P＜0.05).ConclusionVCR can inhibit the proliferation and invasion of INS-1 cells mainly through inhibiting the expressions of Sp1,c-myc and Htert, and the telomerase activity of INS-1,and then inhibiting cell proliferation and reducing the invasive ability.