Reyes-Ramos Ana M, Ramos-Cruz Karla P, Rodríguez-Merced Nelson J, Martínez-Montemayor Michelle M, Franqui-Ríos Nelson D, Ríos-Grant Jan P, Flores Andrea, Maldonado-Martínez Gerónimo, Torres-García Wandaliz, Domenech Maribella
Department of Chemical Engineering, Universidad de Puerto Rico-Mayagüez, Mayagüez, PR 00680, USA.
Department of Biochemistry, Universidad Central del Caribe, School of Medicine-Bayamón, Bayamón, PR 00956, USA.
Cancers (Basel). 2019 Oct 10;11(10):1522. doi: 10.3390/cancers11101522.
The paracrine interaction between tumor cells and adjacent stroma has been associated with the oncogenic activity of the Hedgehog (Hh) pathway in triple-negative breast tumors. The present study developed a model of paracrine Hh signaling and examined the impact of mesenchymal cell sources and culture modalities in the oncogenicity of the Hh pathway in breast tumor cells. Studies consisted of tumor cell monocultures and co-cultures with cancer-associated and normal fibroblasts, tumor cells that undergo epithelial-mesenchymal transition (EMT), or adipose-derived mesenchymal stem cells (ADMSCs). Hh ligand and pathway inhibitors, GANT61 and NVP-LDE225 (NVP), were evaluated in both cell cultures and a mouse xenograft model. Results in monocultures show that tumor cell viability and Hh transcriptional activity were not affected by Hh inhibitors. In co-cultures, down-regulation of , , and in the stroma correlated with reduced tumor growth rates in xenografted tumors and cell cultures, confirming a paracrine interaction. Fibroblasts and EMT cells supported Hh transcriptional activity and enhanced tumor cell growth. Mixed and adjacent culture modalities indicate that tumor growth is supported via fibroblast-secreted soluble factors, whereas enriched tumor stemness requires close proximity between tumor and fibroblasts. Overall this study provides a tumor-mesenchymal model of Hh signaling and highlights the therapeutic value of mesenchymal cells in the oncogenic activity of the Hh pathway.
肿瘤细胞与相邻基质之间的旁分泌相互作用与三阴性乳腺癌中刺猬信号通路（Hh）的致癌活性相关。本研究建立了一种旁分泌Hh信号模型，并研究了间充质细胞来源和培养方式对乳腺肿瘤细胞中Hh信号通路致癌性的影响。研究包括肿瘤细胞单培养以及与癌症相关成纤维细胞、正常成纤维细胞、经历上皮-间质转化（EMT）的肿瘤细胞或脂肪来源间充质干细胞（ADMSC）的共培养。在细胞培养和小鼠异种移植模型中评估了Hh配体和通路抑制剂GANT61和NVP-LDE225（NVP）。单培养结果显示，肿瘤细胞活力和Hh转录活性不受Hh抑制剂影响。在共培养中，基质中 、 和 的下调与异种移植肿瘤和细胞培养中肿瘤生长速率降低相关，证实了旁分泌相互作用。成纤维细胞和EMT细胞支持Hh转录活性并促进肿瘤细胞生长。混合培养和相邻培养方式表明，肿瘤生长由成纤维细胞分泌的可溶性因子支持，而富集的肿瘤干性需要肿瘤与成纤维细胞紧密相邻。总体而言，本研究提供了一种Hh信号的肿瘤-间充质模型，并突出了间充质细胞在Hh信号通路致癌活性中的治疗价值。
