Moreover, immunofluorescence analysis of tissue sections showed that HCC xenografts overexpressing mito-COX-2 had significantly higher percentages of COX-2- and p-Drp1Ser616-positive cells and an increased co-localization of COX-2 and p-Drp1Ser616 than those made of HepG2-pB-MTS-Flag cells (Figure 5C). This evidence concerns the gene PTGS2 and hepatocellular carcinoma.