CTSK expression could be detected in lung tissues such as bronchial and alveolar epithelium and alveolar macrophages [25], however, CTSK was significantly elevated in TAM in advanced NSCLC [26], which may be related to the fact that CTSK could promote the proliferation of A549 cells by directly activating the mTOR signaling pathway, thereby promoting the progression of NSCLC [27]. The gene discussed is MTOR; the disease is non-small cell lung carcinoma.