Department of Chemistry, Center of Nanotechnology and Tissue Engineering -Photobiology and Photomedicine Research Group, Faculty of Philosophy, Sciences and Letters of Ribeirão Preto, University of São Paulo, Ribeirão Preto, São Paulo 14040-901, Brazil.
School of Chemistry and Chemical Engineering, Anhui Key Laboratory of Modern Biomanufacturing, Anhui University, Hefei 230601, China.
ACS Appl Bio Mater. 2022 Feb 21;5(2):723-733. doi: 10.1021/acsabm.1c01138. Epub 2022 Jan 24.
Multicellular tumor spheroids have emerged as well-structured, three-dimensional culture models that resemble and mimic the complexity of the dense and hypoxic cancer microenvironment. However, in brain tumor studies, a variety of glioblastoma multiforme (GBM) cell lines only self-assemble into loose cellular aggregates, lacking the properties of actual glioma tumors in humans. In this study, we used type-I collagen as an extracellular matrix component to promote the compaction of GBM aggregates forming tight spheroids to understand how collagen influences the properties of tumors, such as their growth, proliferation, and invasion, and collagenase to promote collagen degradation. The GBM cell lines U87MG, T98G, and A172, as well as the medulloblastoma cell line UW473, were used as standard cell lines that do not spontaneously self-assemble into spheroids, and GBM U251 was used as a self-assembling cell line. According to the findings, all cell lines formed tight spheroids at collagen concentrations higher than 15.0 μg mL. Collagen was distributed along the spheroid, similarly to that observed in invasive GBM tumors, and decreased cell migration with no effect on the cellular uptake of small active molecules, as demonstrated by uptake studies using the photosensitizer verteporfin. The enzymatic cleavage of collagen affected spheroid morphology and increased cell migration while maintaining cell viability. Such behaviors are relevant to the physiological models of GBM tumors and are useful for better understanding cell migration and the in vivo infiltration path, drug screening, and kinetics of progression of GBM tumors.
多细胞肿瘤球体已成为结构良好的三维培养模型，可模拟致密和缺氧的癌症微环境的复杂性。然而，在脑肿瘤研究中，各种多形性胶质母细胞瘤（GBM）细胞系仅自我组装成松散的细胞聚集体，缺乏人类实际胶质瘤肿瘤的特性。在这项研究中，我们使用 I 型胶原作为细胞外基质成分来促进 GBM 聚集体的紧密组装形成紧密球体，以了解胶原如何影响肿瘤的特性，如生长、增殖和侵袭，以及胶原酶促进胶原降解。U87MG、T98G 和 A172 的 GBM 细胞系以及 UW473 的髓母细胞瘤细胞系被用作不会自发自我组装成球体的标准细胞系，而 GBM U251 则用作自我组装细胞系。结果表明，所有细胞系在胶原浓度高于 15.0μg/mL 时均形成紧密球体。胶原沿球体分布，类似于侵袭性 GBM 肿瘤中观察到的分布，并且对小活性分子的细胞摄取没有影响，这通过使用光敏剂维替泊芬进行摄取研究证明。胶原的酶切作用影响球体形态并增加细胞迁移，同时保持细胞活力。这些行为与 GBM 肿瘤的生理模型相关，有助于更好地理解细胞迁移和体内浸润途径、药物筛选以及 GBM 肿瘤进展的动力学。
