Objective To explore the biological functions and immune cell infiltration effects of non-SMC agglutinin I complex subunit H (NCAPH) in lung adenocarcinoma (LUAD).

Methods Forty-five LUAD patients treated with surgery were selected, and 45 specimens of LUAD tissues and 45 adjacent normal lung tissues were collected. The expression, biological functions and prognostic value of NCAPH in LUAD were analyzed by comprehensive bioinformatics methods. The expression and prognostic value of NCAPH were verified by Western blotting and immunohistochemical (IHC) staining analysis. The effects of knocking down NCAPH on the progression of LUAD cells was explored through MTT, clone formation, scratch and invasion experiments. A Nomogram for predicting the prognosis of LUAD patients was constructed based on the TCGA database.

Results NCAPH was located in the cytosol and nuclear cytoplasm, and its miRNA and protein expressions were upregulated in LUAD tissues (P ＜ 0.05). The overall survival rate of LUAD patients with high NCAPH expression was lower than that of patients with low NCAPH expression (P ＜ 0.05). NCAPH was positively correlated with the angiogenesis (r = 0.201), inflammatory response (r = 0.212), tumor inflammation (r = 0.185), tumor proliferation (r = 0.910), and activity scores of EMT signaling pathways (r = 0.182) (P ＜ 0.05), and negatively correlated with the apoptosis (r = –0.216, P ＜ 0.05). NCAPH was moderately correlated with the memory B cells (r = –0.327) and activated mast cells (r = –0.477) (P ＜ 0.05). Patients with high abundance of memory B cell infiltration had a higher survival rate (P ＜ 0.05). NCAPH was independently associated with the risk of death in LUAD patients regardless of age, gender, stage and smoking (P ＜ 0.05). Knocking down NCAPH could inhibit the viability, clone formation, migration and invasion abilities of LUAD cells (P ＜ 0.05). Nomogram indicators based on NCAPH, age and tumor stage could effectively predict the survival rate of LUAD patients, and significantly increase the clinical net benefit.

Conclusions As an oncogene, NCAPH mediates a poorer prognosis for LUAD patients through multiple biological pathways and functions. Evaluating and locating NCAPH is helpful for the diagnosis, treatment and prognosis assessment of LUAD.