We found increased senescence markers (SA-β-Gal positive cells, upregulation of SASP and senescence markers, increase p21 expression and decrease Ki67 expression) in non-proliferating K-Pα(+)S MSC after KSHV lytic reactivation, indicating that this inhibitory mechanism could explain the arrest in proliferation and the lack of tumor formation of these cells. This evidence concerns the gene MKI67 and neoplasm.