Department of Mechanical Engineering, The Pennsylvania State University, University Park, PA 16802, USA.
Department of Biomedical Engineering, The Pennsylvania State University, University Park, PA 16802, USA.
Cells. 2021 Nov 9;10(11):3084. doi: 10.3390/cells10113084.
Cellular and molecular heterogeneity within tumors has long been associated with the progression of cancer to an aggressive phenotype and a poor prognosis. However, how such intratumoral heterogeneity contributes to the invasiveness of cancer is largely unknown. Here, using a tumor bioengineering approach, we investigate the interaction between molecular subtypes within bladder microtumors and the corresponding effects on their invasiveness. Our results reveal heterogeneous microtumors formed by multiple molecular subtypes possess enhanced invasiveness compared to individual cells, even when both cells are not invasive individually. To examine the molecular mechanism of intratumoral heterogeneity mediated invasiveness, live single cell biosensing, RNA interference, and CRISPR-Cas9 gene editing approaches were applied to investigate and control the composition of the microtumors. An agent-based computational model was also developed to evaluate the influence of NOTCH1 variation on DLL4 expression within a microtumor. The data indicate that intratumoral variation in NOTCH1 expression can lead to upregulation of DLL4 expression within the microtumor and enhancement of microtumor invasiveness. Overall, our results reveal a novel mechanism of heterogeneity mediated invasiveness through intratumoral variation of gene expression.
肿瘤内的细胞和分子异质性长期以来一直与癌症向侵袭性表型和不良预后的进展相关。然而，这种肿瘤内异质性如何促进癌症的侵袭性在很大程度上尚不清楚。在这里，我们使用肿瘤生物工程方法研究了膀胱微肿瘤内的分子亚型之间的相互作用及其对侵袭性的相应影响。我们的结果表明，与单个细胞相比，由多个分子亚型形成的异质性微肿瘤具有增强的侵袭性，即使两个细胞单独都不具有侵袭性。为了研究肿瘤内异质性介导的侵袭性的分子机制，我们应用活单细胞生物传感、RNA 干扰和 CRISPR-Cas9 基因编辑方法来研究和控制微肿瘤的组成。还开发了基于代理的计算模型来评估微肿瘤内 NOTCH1 变异对 DLL4 表达的影响。数据表明，NOTCH1 表达的肿瘤内变异可导致微肿瘤内 DLL4 表达的上调，并增强微肿瘤的侵袭性。总体而言，我们的结果揭示了一种通过肿瘤内基因表达的异质性介导侵袭性的新机制。
