TP53 and neoplasm: LTT and sT, produced from the integrated viral genome, serve as the main oncoproteins promoting the ongoing growth and survival of tumor cells.14 While LT’s activation of p53 may have an anti-tumorigenic effect, sT’s inhibition of p53 tends to favor tumorigenesis.15 MCPyV sT can cause cellular transformation in Rat1 fibroblast cells and facilitate tumor development in p53-null transgenic mice, highlighting sT’s role as a major contributor to oncogenesis.16,17