Divisions of Human Biology and Clinical Research, Fred Hutchinson Cancer Research Center, Seattle, Washington.
Department of Urology, University of Minnesota, Minneapolis, Minnesota.
Prostate. 2020 May;80(6):491-499. doi: 10.1002/pros.23963. Epub 2020 Feb 18.
Prostate cancer (PC) research has relied heavily on patient-derived cell lines, which may be used for in vitro (two-dimensional [2D]) studies or cultivated as three-dimensional (3D) xenografts in mice. These approaches are likely to have differential impacts on cell phenotypes, with implications for experimental outcomes. Therefore, defining and comparing the transcriptional signatures associated with 2D and 3D approaches may be useful for designing experiments and interpreting research results.
In this study, LNCaP, VCaP, and 22Rv1 human PC cells were either cultivated in monolayers or as xenografts in NOD SCID mice, and their gene transcription profiles were quantitated and compared using microarray and real-time polymerase chain reaction techniques. Immunohistochemistry was used to evaluate protein expression in cancer cell xenografts.
Comparisons of gene expression profiles of tumor cells grown in 2D vs 3D environments identified gene sets featuring similar expression patterns in all three cancer cell lines and unique transcriptional signatures associated with 3D vs 2D growth. Pathways related to cell-cell interactions, differentiation, and the extracellular matrix were enriched in 3D conditions. Immunohistochemical analyses confirmed that gene upregulation in xenografts occurred in implanted cancer cells and not in mouse stromal cells. Cultivating cells in vitro in the presence of mouse, rather than bovine serum failed to elicit the gene transcription profile observed in xenografts, further supporting the hypothesis that this profile reflects 3D growth and enhanced microenvironmental interactions, rather than exposure to species-specific serum factors.
Overall, these findings define the expression profiles observed in PC cells cultivated in 2D monolayers and in 3D xenografts, highlighting differentially regulated pathways in each setting and providing information for interpreting research results in model systems.
前列腺癌（PC）研究严重依赖于患者来源的细胞系，这些细胞系可用于体外（二维[2D]）研究或在小鼠中培养为三维（3D）异种移植物。这些方法可能对细胞表型有不同的影响，对实验结果有影响。因此，定义和比较与 2D 和 3D 方法相关的转录特征可能有助于设计实验和解释研究结果。
在这项研究中，LNCaP、VCaP 和 22Rv1 人前列腺癌细胞要么在单层中培养，要么在 NOD SCID 小鼠中作为异种移植物培养，并使用微阵列和实时聚合酶链反应技术定量和比较它们的基因转录谱。免疫组织化学用于评估癌症细胞异种移植物中的蛋白质表达。
比较在 2D 与 3D 环境中生长的肿瘤细胞的基因表达谱，确定了在所有三种癌细胞系中具有相似表达模式的基因集，以及与 3D 与 2D 生长相关的独特转录特征。与细胞-细胞相互作用、分化和细胞外基质相关的途径在 3D 条件下富集。免疫组织化学分析证实，异种移植物中基因的上调发生在植入的癌细胞中，而不是在小鼠基质细胞中。在存在小鼠而不是牛血清的情况下在体外培养细胞未能引起在异种移植物中观察到的基因转录谱，这进一步支持了这样的假设，即该谱反映了 3D 生长和增强的微环境相互作用，而不是暴露于特定物种的血清因子。
总的来说，这些发现定义了在 2D 单层和 3D 异种移植物中培养的 PC 细胞观察到的表达谱，突出了每种设置中差异调节的途径，并为解释模型系统中的研究结果提供了信息。
