Fig. 2
From: Recent advances in understanding tumor stroma-mediated chemoresistance in breast cancer
Chemo-resistance mechanisms mediated by MSCs in breast cancer. Communication between MSCs and breast cancer cells leading to resistance against cytotoxic drugs mostly involves secretory proteins. Following chemotherapy treatment, MSCs secrete increased levels of cytokines (IL-6, IL-8, CXCL1, CXCL7, TGFβ), PUFAs (not shown), plus hyaluronan, exososomes and other molecules. All these are involved in complex inter-cellular communication that ultimately manifests as a chemo-resistant cancer cell phenotype. Direct cell-to-cell interactions are also involved, especially through the functional gap junctions and connexin-interacting proteins and direct receptor communication