人胃癌细胞系的建立及其评价

Establishment and Characterization of Patient Derived Gastric Cancer Cell Lines

目的利用已建立的胃癌人源化异种移植瘤(Patient-derived xenograft,PDX)模型建立胃癌细胞系,并对建立的胃癌细胞系进行生物学特性评价。方法选择12例生长状态良好的胃癌PDX模型,待小鼠移植瘤体积生长至500~900 mm^3时,取出肿瘤组织进行癌细胞的原代培养建立细胞系,通过细胞形态学观察、染色体分析、短片段重复序列(STR)分析、免疫组织化学染色、体外药敏及体内成瘤实验对其生物学特性进行分析鉴定,并在此基础上利用建立成功的胃癌细胞系进行化疗药物药效学评价。结果 12例PDX模型中共成功建立6例胃癌细胞系,细胞系可稳定多次传代。选择其中2例胃癌细胞系(GAXC031和GAXC066)进行生物学特性鉴定。遗传学结果证实,这2例细胞系来自亲本PDX模型,符合恶性胃癌的遗传学特征,在裸小鼠体内具有致瘤性。由细胞系建立的移植瘤模型在保留主要临床生物学特征的前提下,具有成瘤率高,潜伏期短,生长均一性好等特点。体外和体内药敏实验结果均表明,GAXC031对5-氟尿嘧啶有一定的敏感性[体外半抑制浓度(IC_(50))为0.265μmol/L,体内肿瘤生长抑制率(TGI)为30%~50%],而GAXC066不敏感(体外IC_(50)为>200μmol/L,体内TGI<0);2例细胞系对顺铂的敏感性均较强(TGI>60%)。结论成功建立了6例人源胃癌细胞系。对GAXC031和GAXC066细胞系全面的分析和鉴定显示,细胞系与亲本PDX模型高度相关。细胞系体内外药敏实验结果显示,对同一个化疗药物,其体内与体外数据间存在很高的一致性。这些细胞系及相关模型可用于抗癌药物的研发和肿瘤基础研究。

Objective To establish and characterize primary gastric cancer cell lines derived from gastric cancer patient-derived xenograft （PDX） models. Methods Tumors from 12 stable gastric cancer PDX models were selected to establish primary tumor cell lines when the tumor volume reached 500-900 mm3. The established cell lines were characterized by cell morphology, chromosome, STR and immunohistochemical analyses, in vivo tumorigenicity, as well as drug sensitivity in vitro and in vivo. Results Six primary gastric tumor cell lines were successfully established. GAXC031 and GAXC066 were selected and characterized thoroughly. STR analysis confirmed that these 2 cell lines were consistent with their parental PDX models. These 2 cell lines presented the morphological, histological and genomic characteristics of malignant gastric cancer cells. They generated xenograft readily in nude mice and these tumors maintained histology characteristics of the parental PDX tumors. Moreover, compared to the parental PDX models, these 2 cell lines initiated xenografts with higher take rate, shorter incubation period, and better uniformity in tumor growth. In vitro and in vivo drug sensitivity test showed that GAXC031 was more sensitive to 5-fluorouracil than that of GAXC066, while both cell lines were sensitive to cisplatin. Conclusions Six patient derived gastric cell lines were successfully established from PDX models in this study. Deep characterization showed that these cell lines maintained many characteristics of the original PDX models with improved take rate, latent period and uniformity, therefore reoresent useful tools in basic research and drug screening.