The extracellular matrix (ECM) affects cell behaviors, such as survival, proliferation, motility, invasion, and differentiation. The arginine-glycine-aspartic acid (RGD) sequence is present in several ECM proteins, such as fibronectin, collagen type I, fibrinogen, laminin, vitronectin, and osteopontin. It is very critical to develop ECM-like substrates with well-controlled features for the investigation of influence of RGD on the behavior of tumor cells. In this study, poly(ethylene glycol) (PEG)-crosslinked poly(methyl vinyl ether-alt-maleic acid) (P(MVE-alt-MA)) hydrogels (PEMM) with different RGD contents were synthesized, fully characterized, and established as in vitro culture platforms to investigate the effects of RGD content on cancer stem cell (CSC) enrichment. The morphology, proliferation, and viability of SK-OV-3 ovarian cancer cells cultured on hydrogels with different RGD contents, the expression of CSC markers and malignant signaling pathway-related genes, and drug resistance were systematically evaluated. The cell aggregates formed on the hydrogel surface with a lower RGD content acquired certain CSC-like properties, thus drug resistance was enhanced. In contrast, the drug sensitivity of cells on the higher RGD content surface increased because of less CSC-like properties. However, the presence of RGD in the stiff hydrogels (PEMM2) had less effect on the stemness expression than did its presence in the soft hydrogels (PEMM1). The results suggest that RGD content and matrix stiffness can lead to synergetic effects on the expression of cancer cell stemness and the epithelial-mesenchymal transition (EMT), interleukin-6 (IL-6), and Wnt pathways.

细胞外基质（ECM）影响细胞行为，例如存活，增殖，运动，侵袭和分化。精氨酸-甘氨酸-天冬氨酸（RGD）序列存在于几种ECM蛋白中，例如纤连蛋白，I型胶原，纤维蛋白原，层粘连蛋白，玻连蛋白和骨桥蛋白。开发具有良好控制特征的ECM样底物对于研究RGD对肿瘤细胞行为的影响至关重要。在这项研究中，聚（乙二醇）（PEG）-crosslinked聚（甲基乙烯基醚- ALT -马来酸）（P（MVE- ALT -MA））水凝胶（PEMM）具有不同RGD内容进行合成，完全表征，并且建立为体外培养平台以研究RGD含量对癌症干细胞（CSC）富集的影响。系统评价了在不同RGD含量的水凝胶上培养的SK-OV-3卵巢癌细胞的形态，增殖和活力，CSC标志物和恶性信号通路相关基因的表达以及耐药性。RGD含量较低的水凝胶表面上形成的细胞聚集体具有某些CSC样特性，因此增强了耐药性。相反，由于较少的CSC样特性，在较高RGD含量的表面上细胞的药物敏感性增加。但是，刚性水凝胶（PEMM2）中RGD的存在对茎表达的影响小于软水凝胶（PEMM1）中RGD的存在。