Department of Chemical, Materials and Industrial Production Engineering, University of Naples Federico II, P. Le V. Tecchio 80, 80125, Naples, Italy.
CEINGE Advanced Biotechnologies Franco Salvatore, Via G. Salvatore 436, 80131, Naples, Italy.
Sci Rep. 2024 Sep 6;14(1):20837. doi: 10.1038/s41598-024-69570-6.
Tumours often display invasive behaviours that induce fingering, branching and fragmentation processes. The phenomenon, known as diffusional instability, is driven by differential cell proliferation, migration, and death due to the presence of metabolite and catabolite concentration gradients. An understanding of the intricate dynamics of this spatially heterogeneous process plays a key role in the investigation of tumour growth and invasion. In this study, we developed an in vitro tumour invasion assay to investigate cell invasiveness in tumour spheroids under a chemotactic stimulus. Our method, employing tumour spheroids seeded in a 3D collagen gel within a microfluidic chemotaxis chamber, focuses on the role of diffusive gradients. Using Time-Lapse Microscopy, the dynamic evolution of tumour spheroids was monitored in real-time, providing a comprehensive view of the morphological changes and cell migration patterns under different chemotactic conditions. Specifically, we explored the impact of fetal bovine serum (FBS) gradients on the behaviour of CT26 mouse colon carcinoma cells and compared the effects of varying FBS concentrations to two isotropic control conditions. Furthermore, a finite element in silico model was developed to quantify the diffusive flow of nutrients in the chemotaxis chamber and obtain a detailed understanding of tumour dynamics. Our findings reveal that the presence of a chemotactic gradient significantly influences tumour invasiveness, with higher concentrations of nutrients associated with increased cancer growth and cell migration.
肿瘤经常表现出侵袭行为，诱导出指状、分支和碎裂过程。这种现象称为扩散不稳定性，是由于代谢物和分解产物浓度梯度的存在导致的细胞增殖、迁移和死亡的差异所驱动的。了解这种空间异质过程的复杂动力学对于研究肿瘤生长和侵袭起着关键作用。在这项研究中，我们开发了一种体外肿瘤侵袭测定法，以在趋化性刺激下研究肿瘤球体中的细胞侵袭性。我们的方法是将肿瘤球体接种在微流控趋化性室中的 3D 胶原凝胶中，重点研究扩散梯度的作用。使用延时显微镜，实时监测肿瘤球体的动态演变，提供不同趋化条件下形态变化和细胞迁移模式的全面视图。具体来说，我们研究了胎牛血清 (FBS) 梯度对 CT26 小鼠结肠癌细胞行为的影响，并将不同 FBS 浓度的影响与两种各向同性对照条件进行了比较。此外，还开发了一个有限元数值模型来量化趋化室中营养物质的扩散流动，并深入了解肿瘤动力学。我们的研究结果表明，趋化性梯度的存在显著影响肿瘤的侵袭性，较高浓度的营养物质与癌症生长和细胞迁移的增加有关。
