Furthermore, the pathway-based ssGSEA results (Fig. 9H) indicated that the C2 subtype activated more tumour and immune-related pathways, such as DNA replicating, homologous recombination (HR), P53 signaling pathway, mismatch repair, T cell receptor signaling pathway, JAK STAT signaling pathway, B cell receptor signaling pathway, and apoptosis, suggesting that the mtPCDI signature is closely associated with these typical tumour-related pathways. This evidence concerns the gene TP53 and neoplasm.