CCL2 and cholangiocarcinoma: Further, conditioned medium from MSCs exposed to tumor cell-derived extracellular vesicles (EVs) caused an upregulation in STAT3 phosphorylation and proliferation of CCA cells, possibly by secretion of CCL2/MCP1, CXCL1/GRO-α, CXC3CL1/Fractalkine, IL-6, and PDGF-AA (51).