TOX3 is a favorable prognostic indicator and potential immunomodulatory factor in lung adenocarcinoma.

Thymocyte selection-associated high mobility group box (TOX) genes represent a novel family of genes. Deregulated expression of TOXs has been reported in a variety of cancer types, including lung cancer. It has also been reported that TOXs are crucial regulators of the immune system. The present study systematically evaluated the prognostic values of TOX family members using a set of publicly accessible databases, including Oncomine, Kaplan-Meier plotter and cBioPortal. It was revealed that TOX expression profiles differed between lung cancer and normal tissues, and high expression of TOX mRNAs generally predicted improved survival outcomes. Notably, TOX3 expression was significantly increased in lung adenocarcinoma, compared with other pathological subtypes of lung cancer. Survival analysis demonstrated that elevated TOX3 expression was significantly associated with improved progression-free and overall survival in patients with lung adenocarcinoma. Furthermore, correlation analysis indicated that TOX3 expression was negatively correlated with the expression of programmed death-1 receptor (PD-1), PD-ligand 1 and Hepatitis A virus cellular receptor 2 in lung adenocarcinoma. These results indicated that TOX3 is a prognostic indicator and promising immunomodulatory factor in lung adenocarcinoma. Future studies investigating the role of TOX3 in lung cancer immunity are warranted.