HDAC1 and neoplasm: Mice in the HDAC1-shRNA group and the NC group were killed 46 days after inoculation, with the mean tumor weight was markedly lower in the pLVTHM-HDAC1-shRNA group (0.27 ± 0.08 g) and compared to the pLVTHM-shRNA (negative control, NC) group (0.54 ± 0.16 g), respectively (Figure 6D).