University of Saskatchewan Department of Surgery, Royal University Hospital, Saskatoon, Saskatchewan, Canada.
J Thorac Cardiovasc Surg. 2012 Nov;144(5):1192-9. doi: 10.1016/j.jtcvs.2012.08.008. Epub 2012 Sep 12.
Recent studies have suggested that human solid tumors may contain subpopulations of cancer stem cells with the capacity for self-renewal and the potential to initiate and maintain tumor growth. The aim of this study was to use human esophageal cell lines to identify and characterize putative esophageal cancer stem cell populations.
To enrich stemlike cells, Het-1A (derived from immortalized normal esophageal epithelium), OE33, and JH-EsoAd1 (each derived from primary esophageal adenocarcinomas) were cultured using serum-free media to form spheres. A comprehensive analysis of parent and spheroid cells was performed by flow cytometry, Western blot analysis, immunohistochemistry and polymerase chain reaction array to study cancer stem cell-related genes, colony formation assays to assess clonogenicity, xenotransplantation to assess tumorigenicity, and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assays to assess chemosensitivity to 5-fluorouracil and cisplatin.
For all cell lines, clonogenicity, tumorigenicity, and chemoresistance to 5-fluorouracil and cisplatin were significantly higher than for spheroid cells compared with parent cells. Spheroids exhibited an increased frequency of cells expressing integrin α6(bri)/CD71(dim), and Achaete-scute complex homolog 2 messenger RNA and protein were also significantly overexpressed in spheroid cells compared with parent cells.
The higher clonogenicity, tumorigenicity, and drug resistance exhibited by spheroids derived from Het-1A, OE33, and JH-EsoAd1 reflects an enrichment of stemlike cell populations within each esophageal cell line. Esophageal cells enriched for integrin α6(bri)/CD71(dim) and/or overexpressing Achaete-scute complex homolog 2 would appear to represent at least a subpopulation of stemlike cells in Het-1A, OE33, and JH-EsoAd1.
最近的研究表明，人类实体瘤可能包含具有自我更新能力和启动并维持肿瘤生长潜力的癌症干细胞亚群。本研究旨在使用人食管细胞系鉴定和表征推定的食管癌细胞干细胞群体。
为了富集类干细胞，Het-1A（源自永生化正常食管上皮）、OE33 和 JH-EsoAd1（均源自原发性食管腺癌）在无血清培养基中培养以形成球体。通过流式细胞术、Western blot 分析、免疫组织化学和聚合酶链反应阵列对亲本和球体细胞进行全面分析，研究与癌症干细胞相关的基因，进行集落形成测定以评估克隆形成能力，进行异种移植以评估致瘤性，以及 3-（4,5-二甲基噻唑-2-基）-2,5-二苯基四氮唑溴盐测定以评估对 5-氟尿嘧啶和顺铂的化学敏感性。
对于所有细胞系，与亲本细胞相比，球体细胞的克隆形成能力、致瘤性和对 5-氟尿嘧啶和顺铂的化学抗性均显著高于球体细胞。与亲本细胞相比，球体细胞中表达整合素α6(bri)/CD71(dim)的细胞频率增加，并且 Achaete-scute 复合物同源物 2 的信使 RNA 和蛋白也显著过表达。
Het-1A、OE33 和 JH-EsoAd1 衍生的球体显示出更高的克隆形成能力、致瘤性和药物抗性，这反映了每种食管细胞系中类干细胞群体的富集。整合素α6(bri)/CD71(dim)富集的食管细胞和/或过表达 Achaete-scute 复合物同源物 2 的食管细胞似乎代表了 Het-1A、OE33 和 JH-EsoAd1 中至少一部分类干细胞。
