Bone marrow-derived myofibroblasts contribute to the mesenchymal stem cell niche and promote tumor growth

ABSTRACT: Carcinoma-associated fibroblasts (CAFs) that express ?-smooth-muscle-actin (?SMA+) contribute to cancer progression, but their precise origin and role in tumorigenesis is not established. Using mouse models of inflammation-induced gastric cancer, we show that at least 20% of CAFs originate from bone marrow and derive from mesenchymal stem cells (MSCs). Surprisingly, we find that ?SMA+ myofibroblasts (MF) are niche cells normally present in bone marrow and increase markedly in the bone marrow and blood during progression to dysplasia. MSC-derived CAFs that are recruited to the dysplastic stomach express IL-6, Wnt5? and BMP4 and show DNA hypomethylation. Bone marrow (BM)-derived CAFs strongly promote tumor growth in organotypic and xenograft models. In addition, CAFs are generated from MSCs and are recruited to distant tumor sites in a TGF-?- and SDF-1?-dependent manner. Carcinogenesis therefore involves the expansion and relocation of normal bone marrow niche cells to the tumor site where they create a new niche to sustain cancer progression. Since resident (non-BM-derived) CAFs could not be cultured and directly compared to BM-derived CAFs, we additionally isolated total RFP(+) gastric CAFs from aSMA-RFP mice with Helicobacter felis-induced dysplasia, and compared them to GFP(+) BM-derived gastric CAFs from mice with H. felis-induced dysplasia mice that had been transplanted with UBC-EGFP bone marrow. The RFP+ CAFs (HF CAF) represent total CAFs (of which only 20% were BM-derived), while the latter represented only BM-derived CAFs (BM CAF). We compared their gene expression using the Illumina array (MouseWG-6v2) directly after FACS sorting. Interestingly, the GFP+ BM-derived CAFs expressed higher levels of inflammatory genes (IL-6, IL-1?, IL-33) and a number of tumor and stem cell associated factors (CCL5, SPP1, Notch3, MMP9, CD47, CXCR4, PARP10,) compared to the total (RFP+) population of gastric CAFs. Comparison of bone marrow-derived GFP-labeled gastric CAFs versus all gastric CAFs.

ORGANISM(S): Mus musculus

SUBMITTER: Michael Quante 

PROVIDER: E-GEOD-23548 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress