Systematic analysis of secreted proteins reveals synergism between IL6 and other proteins in soft agar growth of MCF10A cells

Abstract

IntroductionBreast cancer, the most common malignancy in women, still holds many secrets. The causes for non-hereditary breast cancer are still unknown. To elucidate any role for circulating naturally secreted proteins, a screen of secreted proteins' influence of MCF10A cell anchorage independent growth was set up.MethodsTo systematically screen secreted proteins for their capacity to transform mammalian breast epithelial cells, a soft agar screen of MCF10A cells was performed using a library of ~ 470 secreted proteins. A high concentration of infecting viral particles was used to obtain multiple infections in individual cells to specifically study the combined effect of multiple secreted proteins.ResultsSeveral known breast cancer factors, such as Wnt, FGF and IL were retained, as well as factors that were previously unknown to have a role in breast cancer, such as paraoxonase 1 and fibroblast growth factor binding protein 2. Additionally, a combinatory role of Interleukin 6 with other factors in MCF10A anchorage-independent growth is demonstrated.ConclusionThe transforming effect of combinations of IL6 with other secreted proteins allows studying the transformation of mammary epithelial cells in vitro, and may also have implications in in vivo studies where secreted proteins are upregulated or overexpressed.

Disequilibrium of BMP2 Levels in the Breast Stem Cell Niche Launches Epithelial Transformation by Overamplifying BMPR1B Cell Response

“…The MCF10A cell line (nonmalignant fibrocystic mammary tissue, p16/CDKN2A deletion, MYC amplification) ( Kadota et al., 2010 ) is considered as a model for immature mammary epithelial cells that differentiate in 3D culture (3D terminal ductal lobular unit [TDLU] assay) ( Debnath et al., 2003; Neve et al., 2006 ). Used as a preneoplastic model, MCF10A cells form colonies in soft agar and tumors in mice after oncogenic events ( Pires et al., 2013 ) favored by IL-6 ( Van Huffel et al., 2011 ). MCF10A cells were exposed to long-term BMP2 or BMP4 treatment with or without IL-6 and assayed weekly for their tumorigenic properties in the absence of cytokines ( Figure 4 A).…”

The Tumor Promotional Role of Adipocytes in the Breast Cancer Microenvironment and Macroenvironment

“…87 In addition to promoting therapy resistance, 81,87 FGF-2 alone and FGFs with IL-6 synergize to promote the malignant transformation of mammary epithelial cells in vitro. 88,89 Separate studies have implicated cytokines, including leptin, IL-6, and IL-8, from adipose depots local to and distant from the tumor, in breast cancer risk, cell proliferation and migration, 90,91 and tumor resistance to therapies that target angiogenesis or ER. 81,92 In some cases, signals from adipocytes are communicated to infiltrating immune cells (eg, neutrophils, macrophages, T cells) 81,93 and directly to cancer cells (Figure 2).…”