CXCL16 and neoplasm: Next, since CCL5 and CXCL16 secreted from MEPs located at the bone marrow niche may affect immune cells at the tumor microenvironment, we measured the levels of CXCL16 and CCL5 in peripheral blood and tumors, 72 h after treatment with gemcitabine chemotherapy to see whether they can explain the anti-tumor immunity.