Abbaspour Ali, Martinez Cavazos Ana L, Patel Roshan, Yang Ning, McGregor Stephanie M, Brooks Erin G, Masters Kristyn S, Kreeger Pamela K
Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI 53706, USA.
Department of Pathology and Laboratory Medicine, University of Wisconsin-Madison, 1111 Highland Ave, WIMR 5037, Madison, WI 53705, USA.
Acta Biomater. 2025 Jun 15;200:299-312. doi: 10.1016/j.actbio.2025.05.035. Epub 2025 May 13.
Collagen type I, a key structural component of the extracellular matrix (ECM), is frequently altered in cancer, with altered fiber organization at the primary tumor site linked to metastasis and poor patient outcomes. Here, we demonstrate that collagen fibers are also altered in metastatic sites such as the omentum of patients with high-grade serous ovarian cancer (HGSOC). Specifically, we observed a significant increase in fiber density, alignment, and width. To determine if the increase in fiber density supports metastasis, we used a semi-interpenetrating methacrylated gelatin (gelMA) network in combination with increasing fibrillar collagen. Cancer cells had significantly increased adhesion as collagen fiber density increased. To determine the responsible mechanisms, we used orthogonal systems to examine 1) the different adhesion peptides exposed in collagen (GFOGER) and gelatin (RGD), and 2) the physical structure of fibers. Cells had minimal response to GFOGER, either alone or in combination with RGD, suggesting that increased adhesion did not result from this collagen-specific interaction. Cell adhesion was significantly higher on electrospun PCL-gelatin fibers compared to flat PCL-gelatin substrates, suggesting that increased cell adhesion resulted from fiber structure. We next investigated the cellular mechanisms involved in increased adhesion on gelMA/coll and found that actin polymerization, but not myosin II contractility, was needed. We further demonstrated that cells on fibrous gels had more robust actin polymerization, and that this resulted in greater adhesion strength. Combined, these results suggest that the increase in collagen fibers with tumor metastasis will support the development of additional metastases. STATEMENT OF SIGNIFICANCE: This work advances the evaluation of the matrisome of the omentum, the most common metastatic site in advanced ovarian cancer by characterizing how collagen fibers change with disease progression. To examine the effect of collagen fibers on metastasis, we utilized a suite of in vitro biomaterials to identify a novel role for collagen fibers in supporting cell adhesion through increased actin dynamics during nascent adhesion formation, which results in increased adhesion strength at later times.
I型胶原蛋白是细胞外基质（ECM）的关键结构成分，在癌症中经常发生改变，原发性肿瘤部位纤维组织的改变与转移及患者预后不良有关。在此，我们证明在高级别浆液性卵巢癌（HGSOC）患者的大网膜等转移部位，胶原纤维也会发生改变。具体而言，我们观察到纤维密度、排列和宽度显著增加。为了确定纤维密度的增加是否支持转移，我们使用了半互穿甲基丙烯酸化明胶（gelMA）网络并结合增加的纤维状胶原蛋白。随着胶原纤维密度的增加，癌细胞的黏附力显著增强。为了确定其作用机制，我们使用正交系统来研究：1）胶原蛋白（GFOGER）和明胶（RGD）中暴露的不同黏附肽；2）纤维的物理结构。细胞对单独的GFOGER或与RGD联合使用时反应极小，这表明黏附力增加并非源于这种胶原蛋白特异性相互作用。与扁平的聚己内酯 - 明胶底物相比，电纺聚己内酯 - 明胶纤维上的细胞黏附力显著更高，这表明细胞黏附力增加是由纤维结构导致的。接下来，我们研究了gelMA/胶原上黏附力增加所涉及的细胞机制，发现需要肌动蛋白聚合，但不需要肌球蛋白II收缩性。我们进一步证明，纤维凝胶上的细胞具有更强的肌动蛋白聚合，这导致了更大的黏附强度。综合来看，这些结果表明随着肿瘤转移胶原纤维的增加将支持更多转移灶的形成。重要性声明：这项工作通过表征胶原纤维如何随疾病进展而变化，推进了对大网膜（晚期卵巢癌最常见的转移部位）基质组的评估。为了研究胶原纤维对转移的影响，我们利用了一系列体外生物材料，以确定胶原纤维在新生黏附形成过程中通过增加肌动蛋白动力学来支持细胞黏附的新作用，这在后期导致黏附强度增加。
