TP53 and small cell lung carcinoma: Firstly, in contrast to the association of HRGcluster B with intracellular energy metabolism, HRGcluster A was significantly enriched in functions related to intercellular substance exchange and cell membrane alteration, such as “axon guidance,” “ECM receptor interaction,” “glycosphingolipid biosynthesis lacto and neolacto series,” and “glycosaminoglycan biosynthesis keratin sulfate.” Moreover, HRGcluster A was also closely associated with cancer development, as it was enriched in pathways like “basal cell carcinoma,” “small cell lung cancer,” and “P53 signaling pathway” (Figure 4a).