In patients with post-acute COVID-19, a higher level of let-7b expression occurs compared to acute infection; this potentially suggests a role of let-7b in the immune response and repair function through the targeting of genes such as V-Rel avian reticuloendotheliosis viral oncogene homolog B (RELB), IL-6, KH-type splicing regulatory protein (KHSRP), euchromatic histone lysine methyltransferase 2 (EHMT2), lysine demethylase 2B (KDM2B), C-MYC, and LIN28B [71]. This evidence concerns the gene KDM2B and COVID-19.