TP53 and HIV-1 infection: To investigate whether p53 also inhibits HIV-1 infection depending on cell cycle status, non-cycling HCT116 p53+/+ and HCT116 p53−/− cells were prepared by serum starvation for 24 h, then the cell cycle statuses of both cycling and non-cycling cells were analyzed by flow cytometry after PI staining and EdU incorporation.