NKD2 and viral myocarditis: There were totally 53 pathways significantly enriched in the NKD2 high-expressed group, and the top 9 most significant pathways included T cell receptor signaling pathway, B cell receptor signaling pathway, thyroid cancer, viral myocarditis, antigen processing and presentation, cytosolic DNA sensing pathway, pathways in cancer, acute myeloid leukemia, and JAK/STAT signaling pathway (Fig. 3A–I).