Organotypic three-dimensional cancer cell cultures mirror drug responses in vivo: Lessons learned from the inhibition of EGFR signaling

Complex three-dimensional (3D) in vitro model systems that recapitulate human tumor biology are essential to better understand the pathophysiology of the disease and to aid in the discovery of novel anti-cancer therapies. 3D organotypic cultures exhibit intercellula communication, nutrient and oxygen gradients, and cell polarity that is lacking in traditional two-dimensional (2D) monolayer cultures. In the present study, we could demonstrate that 2D and 3D cancer models exhibit different drug sensitivities towards both targeted inhibitors of EGFR signaling and broad acting cytotoxic agents. Changes in the kinase activities of Erb family members and differential expression of apoptosis- and survival-associated genes before and after drug treatment may account for the differential drug sensitivities. Importantly, EGFR oncoprotein addiction was evident only in the 3D cultures mirroring the effect of EGFR inhibition in the clinic. Furthermore, targeted drug efficacy was strongly increased when incorporating cancer-associated fibroblasts into the 3D cultures. Taken together, we could provide conclusive evidence that complex 3D cultures are more predictive of the clinical outcome than their 2D counterparts. In the future, 3D cultures will be instrumental for understanding the mode of action of drugs, identifying genotype-drug response relationships and developing patient-specific and personalized cancer treatments. 6 samples, 3 replicates each. Cell line: HCC827. Matrigel coating: yes, no. Dimensionality: 2D, 3D.

能够重现人类肿瘤生物学特性的复杂三维（3D）体外模型系统，对于深入解析该疾病的病理生理学机制、助力新型抗癌疗法的研发至关重要。与传统二维（2D）单层培养体系相比，三维器官型培养具备细胞间通讯、营养与氧浓度梯度分布以及细胞极性等关键特征。本研究证实，二维与三维肿瘤模型对表皮生长因子受体（EGFR）信号通路靶向抑制剂以及广谱细胞毒性药物均表现出不同的药物敏感性。药物处理前后，Erb家族成员的激酶活性变化、凋亡与存活相关基因的差异表达，或可解释这种药物敏感性差异。值得注意的是，EGFR癌蛋白成瘾性仅在三维培养体系中显现，这与临床中EGFR抑制疗法的治疗效果高度契合。此外，将癌症相关成纤维细胞引入三维培养体系时，靶向药物的疗效显著提升。综上，本研究提供了确凿证据，表明复杂三维培养体系相较于二维培养体系，能够更精准地预测临床治疗结局。未来，三维培养体系将在解析药物作用机制、明确基因型-药物反应关联以及开发患者个体化癌症治疗方案等方面发挥关键作用。本数据集包含6个样本，每个样本设置3次生物学重复。细胞系：HCC827。基质胶（Matrigel）包被：是、否。培养维度：二维（2D）、三维（3D）。