PLEK2 and lung adenocarcinoma: Among the genes included in the prognostic model, PLEK2 has been reported in five studies as a prognostic marker for lung adenocarcinoma (Cheng et al., 2019; Li, 2020; Ishida et al., 2013; O'Leary et al., 2019; Antsotegi-Uskola et al., 2020).