For example, in the treatment of keloid with HBOT, song (Song et al., 2018) observed that it could reduce the formation of scar by reducing inflammatory factors such as IL-6 and IL-8, while another experiment (Y. Hao et al., 2020) did not observe the same changes, but the alterations in expression of IL-12p40 and IL-RA were observed. The gene discussed is IL6; the disease is keloid.