The molecular subtypes of BRCA, OV, HNSC, ESCA, LIHC, LUSC, UCEC, KIRP, PCPG, COAD, and STAD were significantly correlated with JCHAIN expression, implying that JCHAIN may play an important role in the tumour microenvironment and influence the molecular subtypes of individual tumours (Figure 3B). The gene discussed is JCHAIN; the disease is neoplasm.