PCNA and neoplasm: Results from an immunohistochemistry assay showed that hMBSCs significantly decreased the positive rates of PCNA in the HeLa/hMBSC-coinjected tumor tissues compared with those in the HeLa cells alone tissues and HeLa/NIH 3T3-coinjected tumor tissues (Figures 5(f) and 5(g)), which was consistent with the in vitro results.