PARP1 and neoplasm: Recent studies showed that MSCs could affect tumor progression through secreted factors influencing immunoregulation (IL6, IL10, TGF-beta and PGE2), tumor cell survival (STAT3, MAPK, PARP1 and caspase3), tumor angiogenesis (VEGF, bFGF, IL6, IL8, angiopoietin), and tumor cell motility/metastasis (CCL5, CXCL12 and IGF1)45–47.