IL21 and neoplasm: Moreover, hUC-MSC-IL-21 suggestively weakened SKOV3 (77) and A2780 (78) ovarian cancer volume in xenografts by affecting the serum levels of IFN-γ and TNF-α, concurrently restoring the expression of natural killer group 2 member D (NKG2D) and MHC class I polypeptide-related sequence A (MICA) molecules in the tumor microenvironment (77).