Pleiotropic effects of cancer cells’ secreted factors on human stromal (mesenchymal) stem cells

Abstract

IntroductionStudying cancer tumors’ microenvironment may reveal a novel role in driving cancer progression and metastasis. The biological interaction between stromal (mesenchymal) stem cells (MSCs) and cancer cells remains incompletely understood. Herein, we investigated the effects of tumor cells’ secreted factors as represented by a panel of human cancer cell lines (breast (MCF7 and MDA-MB-231); prostate (PC-3); lung (NCI-H522); colon (HT-29) and head & neck (FaDu)) on the biological characteristics of MSCs.MethodsMorphological changes were assessed using fluorescence microscopy. Changes in gene expression were assessed using Agilent microarray and qRT-PCR. GeneSpring 12.1 and DAVID tools were used for bioinformatic and signaling pathway analyses. Cell migration was assessed using a transwell migration system. SB-431542, PF-573228 and PD98059 were used to inhibit transforming growth factor β (TGFβ), focal adhesion kinase (FAK), and mitogen activated protein kinase kinase (MAPKK) pathways, respectively. Interleukin-1β (IL1β) was measured using ELISA.ResultsMSCs exposed to secreted factors present in conditioned media (CM) from FaDu, MDA-MB-231, PC-3 and NCI-H522, but not from MCF7 and HT-29, developed an elongated, spindle-shaped morphology with bipolar processes. In association with phenotypic changes, genome-wide gene expression and bioinformatics analysis revealed an enhanced pro-inflammatory response of those MSCs. Pharmacological inhibitions of FAK and MAPKK severely impaired the pro-inflammatory response of MSCs to tumor CM (approximately 80% to 99%, and 55% to 88% inhibition, respectively), while inhibition of the TGFβ pathway was found to promote the pro-inflammatory response (approximately 3-fold increase). In addition, bioinformatics and pathway analysis of gene expression data from tumor cell lines combined with experimental validation revealed tumor-derived IL1β as one mediator of the pro-inflammatory phenotype observed in MSCs exposed to tumor CM.MSCs exhibited significant tropism toward secreted factors from the aforementioned tumor cell lines, while both normal and MSCs exposed to tumor CM were capable of attracting human peripheral blood mononuclear cells (PBMCs).ConclusionsOur data revealed tumor-derived IL1β as one mediator of the pro-inflammatory response in MSCs exposed to tumor CM, which was found to be positively regulated by FAK and MAPK signaling and negatively regulated by TGFβ signaling. Thus, our data support a model where MSCs could promote cancer progression through becoming pro-inflammatory cells within the cancer stroma.

Mesenchymal stem cells are enriched in head neck squamous cell carcinoma, correlates with tumour size and inhibit T-cell proliferation

“…Interestingly tumour-MSCs resulted were able to attract CD4+ and CD8+ T cells in in vitro chemotactic assays, supporting the idea that tumour-MSC are able to actively attract T lymphocytes and then suppress them in terms of cell proliferation and cytokine production. These data are consistent with a recent publication where it has been demonstrated that MSC derived from different tumours are able to attract in vitro peripheral blood mononuclear cells ( Al-toub et al , 2013 ).…”

Large-Scale Analysis of Gene Expression Data Reveals a Novel Gene Expression Signature Associated with Colorectal Cancer Distant Recurrence

“…The Cox proportional hazards multiple regression model was used to identify the independent prognostic factors and to correct the effect of potential confounding variables, such as gender (male vs female), age (> 65y vs < 65y), tumor stage (stage 3/4 vs stage 1/2), and of cancer type (colon adenocarcinoma vs rectal adenocarcinoma vs mucinous adenocarcinoma of the colon and rectum) on OS and DFS using MedCalc 16.8.4 (MedCalc, Mariakerke, Belgium). Pathway analyses were conducted using DAVID functional annotation and clustering bioinformatics tool, as described in our previous reports [14, 15]. Statistical analyses and graphing were performed using Graphpad Prism 6.0 software (Graphpad Software, San Diego, CA, USA).…”

microRNA-320/RUNX2 axis regulates adipocytic differentiation of human mesenchymal (skeletal) stem cells

“…Data analyses were conducted using GeneSpring 12.0 software (Agilent Technologies) and DAVID bioinformatic tool as described before. 52 , 53 Percentile Shift was used for data normalization while Benjamini–Hochberg false discovery rate method was used for multiple testing corrections. The gene expression profiling in hMSCs transfected with miR-320c and the gene expression profiling during adipogenic differentiation of hMSCs data sets were deposited to the GEO, accession numbers GSE59458 and GSE59450, respectively.…”