Correlation Study on the Expression of INSR, IRS-1, and PD-L1 in Nonsmall Cell Lung Cancer

To study the expression and correlation of insulin receptor (INSR), insulin receptor substrate-1 (IRS-1), and programmed cell death ligand-1 (PD-L1) in nonsmall cell lung cancer (NSCLC).

45 lung cancer tissues and 30 adjacent normal tissues of NSCLC patients diagnosed in the Second Affiliated Hospital of Shandong First Medical University from June 2019 to August 2020 were selected. The expressions of INSR, IRS-1, and PD-L1 proteins in tumor tissues and adjacent tissues of NSCLC were detected by immunohistochemical staining.

The expression of INSR and IRS-1 in NSCLC was significantly higher than that in adjacent normal lung tissue (P < 0.05). INSR expression had statistical significance with the degree of pathological differentiation of nonsmall cell carcinoma (P = 0.031), but had no significant association with age, gender, pathological type, TNM stage, and lymph node metastasis status (P > 0.05). There was no significant correlation between IRS-1 positive expression and NSCLC patients' age, gender, pathological typing, degree of differentiation, TNM stage, and lymph node metastasis (P > 0.05). PD-L1 positive expression was correlated with lymph node metastasis of NSCLC (P = 0.028), while there was no significant correlation with gender, age, pathological type, TNM stage, and pathological differentiation degree of NSCLC patients (P > 0.05). Spearman correlation analysis showed that PD-L1 protein expression had a significant positive correlation with IRS-1 protein expression (r = 0.373), but was not correlated with the expression of INSR protein.

IRS-1 may be involved in the regulation of PD-L1 expression and mediate the occurrence of tumor immune escape, which is expected to become a new target for NSCLC immunotherapy and provide new clinical evidence for immunosuppressive therapy.