In addition to studies by Malik et al. (2018) and Wang T. et al. (2018), which concluded that CARD9 is an anti-tumor molecule in the development of CAC, more studies have found that CARD9 plays a pro-cancer role in CRC using CARD9–/– mice (Yang et al., 2014; Leo et al., 2015; Bergmann et al., 2017). Here, CARD9 is linked to cancer.