Department of Urology (Prostate Disease Center), College of Medicine and Flow Cytometry Core Facility, University of Florida, Gainesville, Florida 32610, USA.
J Urol. 2010 May;183(5):2045-53. doi: 10.1016/j.juro.2009.12.092. Epub 2010 Mar 19.
We identified a discrete population of stem cell-like tumor cells expressing 5 essential transcription factors required to reprogram pluripotency in prostate tumor cell lines and primary prostate cancer tissue.
DU145 and PC3 human prostate cancer cell lines (ATCC), tumor tissue from patients with prostate cancer and normal prostate tissue were evaluated for the reprogramming factors OCT3/4 (Cell Signaling Technology), SOX2, Klf4 (Santa Cruz Biotechnology, Santa Cruz, California), Nanog (BioLegend) and c-Myc (Cell Signaling) by semiquantitative reverse transcriptase-polymerase chain reaction, histological and immunohistochemical analysis. Stem cell-like tumor cells were enriched by flow cytometric cell sorting using E-cadherin (R&D Systems) as a surface marker, and soft agar, spheroid and tumorigenicity assays to confirm cancer stem cell-like characteristics.
mRNA expression of transcription factors OCT3/4 and SOX2 highly correlated in primary prostate tumor tissue samples. The number of OCT3/4 or SOX2 expressing cells was significantly increased in prostate cancer tissue compared to that in normal prostate or benign prostate hyperplasia tissue (p <0.05). When isolated from the DU145 and PC3 prostate cancer cell lines by flow cytometry, stem cell-like tumor cells expressing high OCT3/4 and SOX2 levels showed high tumorigenicity in immunodeficient mice. In vivo growth of the parental DU145 and PC3 prostate cancer cell lines was inhibited by short hairpin RNA knockdown of OCT3/4 or SOX2.
Data suggest that prostate tumor cells expressing pluripotent stem cell transcription factors are highly tumorigenic. Identifying such cells and their importance in prostate cancer growth could provide opportunities for novel targeting strategies for prostate cancer therapy.
我们鉴定出了一个离散的肿瘤干细胞样细胞群体，这些细胞表达了重编程前列腺肿瘤细胞系和原发性前列腺癌组织中多能性所需的 5 个必需转录因子。
通过半定量逆转录聚合酶链反应、组织学和免疫组织化学分析，对 DU145 和 PC3 人前列腺癌细胞系（ATCC）、前列腺癌患者肿瘤组织和正常前列腺组织进行了重编程因子 OCT3/4（Cell Signaling Technology）、SOX2、Klf4（Santa Cruz Biotechnology，Santa Cruz，加利福尼亚州）、Nanog（BioLegend）和 c-Myc（Cell Signaling）的检测。通过使用 E-钙黏蛋白（R&D Systems）作为表面标志物的流式细胞分选对肿瘤干细胞样细胞进行了富集，通过软琼脂、球体和肿瘤形成能力测定来确认肿瘤干细胞样特性。
在原发性前列腺肿瘤组织样本中，转录因子 OCT3/4 和 SOX2 的 mRNA 表达高度相关。与正常前列腺或良性前列腺增生组织相比，前列腺癌组织中 OCT3/4 或 SOX2 表达细胞的数量显著增加（p <0.05）。当通过流式细胞术从 DU145 和 PC3 前列腺癌细胞系中分离出来时，表达高 OCT3/4 和 SOX2 水平的肿瘤干细胞样细胞在免疫缺陷小鼠中具有高致瘤性。OCT3/4 或 SOX2 的短发夹 RNA 敲低抑制了亲本 DU145 和 PC3 前列腺癌细胞系的体内生长。
数据表明，表达多能干细胞转录因子的前列腺肿瘤细胞具有高度的致瘤性。鉴定出这些细胞及其在前列腺癌生长中的重要性，可为前列腺癌治疗的新靶向策略提供机会。
