转染GKLF基因对人胃癌细胞SGC-7901裸鼠移植瘤的抑制作用

GKLF transfection inhibits the growth of xenograft tumors derived from human gastric carcinoma cell line SGC-7901 in nude mice

目的:研究转染GKLF基因对人胃癌SGC-7901细胞裸鼠皮下移植瘤的作用,探讨GKLF在胃癌中可能的作用机制.方法:将外源性重组真核质粒pcDNA3.1-GKLF转染到人胃癌细胞株SGC-7901内,经G418筛选并建立高表达GKLF的稳定转染细胞株.稳定表达该基因的细胞为SGC7901-pcDNA3.1-GKLF组,转染空质粒细胞及未处理细胞为对照组(SGC7901-pcDNA3.1组和SGC-7901组),建立裸鼠荷瘤模型.监测肿瘤生长状况、成瘤潜伏期,HE染色观察肿瘤病理学变化,免疫组织化学法检测裸鼠皮下移植瘤组织内GKLF、Ki-67蛋白的表达.结果:与SGC-7901组和SGC7901-pcDNA3.1组相比,SGC7901-pcDNA3.1-GKLF组成瘤潜伏期延长,差异具有统计学意义(14.67d±3.08dvs8.33d±1.03d,8.67d±1.03d,均P<0.05).SGC7901-pcDNA3.1-GKLF组皮下移植瘤质量低于SGC-7901组和SGC7901-pcDNA3.1组,移植瘤生长受抑,差异具有统计学意义(4.46g±0.92gvs8.05g±1.66g,7.82g±1.14g,均P<0.05).SGC7901-pcDNA3.1-GKLF组中移植瘤细胞分化较SGC-7901组和SGC7901-pcDNA3.1组好,皮下移植瘤组织内GKLF蛋白阳性表达比例升高(4/6vs2/6,2/6)、Ki-67蛋白阳性表达比例降低(1/6vs4/6,4/6).结论:GKLF基因可能通过下调Ki-67的表达而抑制胃癌SGC-7901细胞裸鼠皮下移植瘤的生长,以GKLF为靶点的基因治疗有潜在临床应用前景.

AIM： To investigate the effects of transfection of the gut-enriched Krüppel-like factor （GKLF） gene on the growth of xenograft tumors derived from human gastric carcinoma cell line SGC-7901 in nude mice and to explore the potential role of the GKLF gene in gastric carcino-genesis. METHODS： A recombinant plasmid carrying the GKLF gene （pcDNA3.1-GKLF） was transfected into SGC-7901 cells by lipofectin-mediated method. Cells stably expressing the GKLF gene were selected using G418. SGC-7901 cells untransfected and those transfected with empty pcDNA3.1 plasmid were used as controls. A xenograft tumor model was then established. Tumor growth was monitored. Tumor histopathological changes were determined by hematoxylin and eosin （HE） staining. The expression of GKLF and Ki-67 proteins in xenograft tissue was detected by immunohistochemistry. RESULTS： Compared with the SGC7901pcDNA3.1 and SGC-7901 groups, the period of latency was significantly lengthened in the SGC7901-pcDNA3.1-GKLF group （14.67 d ± 3.08 d vs 8.33 d ± 1.03 d, 8.67 d ± 1.03 d, both P 0.05）. The weight of xenograft tumors in the SGC7901pcDNA3.1-GKLF group was significantly lower than that in the SGC7901-pcDNA3.1 and SGC-7901 groups （4.46 g ± 0.92 g vs 8.05 g ± 1.66 g, 7.82 g ± 1.14 g, both P 0.05）. The degree of tumor differentiation in the SGC7901-pcDNA3.1GKLF group was better than that in the other two groups. Furthermore, the positive proportion of GKLF protein expression in xenograft tissue was increased while that of Ki-67 protein expression was decreased in the SGC7901pcDNA3.1-GKLF group when compared with the other two groups （4/6 vs 2/6, 2/6; 1/6 vs 4/6, 4/6）. CONCLUSION： Transfection of the GKLF gene inhibits the growth of subcutaneous xenograft tumors derived from SGC-7901 cell line in nude mice by down-regulating the expression of Ki-67. The GKLF gene is a potential target for gene therapy of gastric carcinoma.