STAT3 and lung adenocarcinoma: Although the STAT3 pathway has been proven by many studies to be a key factor in many types of cancer (Xiu-Ping et al., 2018) (Attia et al., 2017) (Kopechek et al., 2015), there is only one study reporting that RIPK4 can significantly inhibit STAT3 signalling and inhibit cancer progression in lung adenocarcinoma 10.