重组TNF-α慢病毒感染的脐血间质干细胞对胃癌移植瘤生长的抑制作用

Inhibitory effect of umbilical cord blood mesenchymal stem cells infected with reconstructed lentivirus-TNF-α on growth of gastric cancer transplantation tumors

目的:以脐血间质干细胞(umbilical cord blood mesenchyme stem cell,UCBMSC)作为肿瘤坏死因子-α(tumor necro-sis factor-alpha,TNF-α)载体,研究重组TNF-α慢病毒Lv-TNF-α感染的UCBMSC对胃癌移植瘤生长的抑制作用。方法:人胃癌细胞SGC-7901注射到裸鼠腹股沟皮下建立胃癌移植瘤裸鼠模型。将表达TNF-α的重组慢病毒Lv-TNF-α和对照慢病毒Lv-EGFP分别感染UCBMSC后获得Lv-TNF-α感染的UCBMSC(UCBMSC-TNF-α)以及Lv-EGFP感染的UCBMSC(UCBMSC-EGFP)。荷瘤裸鼠随机分为3组:分别注射UCBMSC-TNF-α、UCBMSC-EGFP及生理盐水(NaCl),观察注射后瘤体生长情况,RT-PCR和ELISA方法分别测定各组胃癌组织中TNF-αmRNA和蛋白的表达;H-E染色观察瘤体的坏死情况。结果:成功建立SGC-7901胃癌细胞裸鼠移植瘤模型。治疗后三组荷瘤裸鼠肿瘤体积分别为(0.51±0.27)、(0.64±0.36)和(1.21±0.80)cm3,UCBMSC-TNF-α组肿瘤体积最小(F=3.88,P<0.05);RT-PCR法检测结果显示,3组荷瘤裸鼠肿瘤组织TNF-αmRNA分别为(1.92±0.12)、(1.21±0.26)、(0.81±0.22),UCBMSC-TNF-α组TNF-αmRNA表达量最大(F=54.82,P<0.01);ELISA法检测结果显示,3组荷瘤裸鼠肿瘤组织TNF-α蛋白表达分别为(148.29±3.76)、(78.22±6.24)、(42.80±3.02)pg/ml,MSC-TNF-α组表达量最大(F=694.54,P<0.01);H-E染色病理切片显示,UCBMSC-TNF-α治疗组肿瘤坏死面积最大。结论:TNF-α转基因UCBMSC可通过旁分泌TNF-α抑制胃癌的生长。

Objective： To study the inhibitory effect of umbilical cord blood mesenehymal stem cells （UCBMSCs） in- fected with reconstructed lentivirus-TNF-α on growth of gastric cancer transplantation tumors, based on UCBMSC as a TNF-α carrier. Methods： The human gastric cancer SGC-7901 cells were injected into nude mice subcutaneously groin. The model of transplanted SGC-7901 cells in nude mice was set up. The reconstructed lentivirus （Lv-TNF-cx） and empty lentivirus （Lv-EGFP） were added to UCBMSC, and UCBMSC-TNF-α cells and control UCBMSC-EGFP cells were ob- tained. Tumor-bearing nude mice were separated into three groups randomly： a UCBMSC-TNF-α group, an UCBMSC-EG- FP group and a NaCl group. The nude mice in these three groups were injected around the tumor with UCBMSC-TNF-α cells, UCBMSC-EGFP cells or NaCl. The transplanted gastric cancer volume and weight was observed; the expressions of TNF-α mRNA and protein in the three groups were determined by RT-PCR and ELISA; and the necrosis areas in the tumors were observed by H-E staining. Results： The transplantation tumor model was established in the nude mice suc- cessfully. The transplanted tumor average volume in the three groups were （0.51 ± 0.27 ）, （0.64 ± 0.36） and （1.21 ± 0.80） cm3, and the transplanted tumor average volume in the UCBMSC-TNF-α group was minimum （ F = 3.88, P 〈0. 05 ） ; The expressions of TNF-α mRNA in the three groups were （ 1.92 ± 0.12）, （ 1.21 ± 0.26） and （0.81±0. 22）, and the expression of TNF-α mRNA in the UCBMSC-TNF-α group was maximum （ F = 54.82, P 〈 0.01 ） ; The expres- sions of TNF-α protein in the three groups were （ 148.29 ±3.76）, （78.22 ± 6.24） and （42.80 ± 3.02） pg/ml, and the expression of TNF-α protein in the UCBMSC-TNF-α group was maximum （F = 694.54, P 〈 0.01 ） ; H-E stained biopsy revealed that the largest tumor necrosis was in the UCBMSC-TNF-α treatment group. Conclusion： Transgenic UCBMSCs can paracrine TNF-α, which has an inhibitory effect on gastric cancer.