CXCR1 correlates to poor outcomes of EGFR-TKI against advanced non-small cell lung cancer by activating chemokine and JAK/STAT pathway.

Abstract

OBJECTIVE\nCXCR1, a member of the seven-transmembrane chemokine receptor family, promotes cell proliferation and metastasis in many tumors. The present study was undertaken to explore the interrelation between CXCR1 expression and the prognosis of advanced non-small cell lung cancer (NSCLC) in addition to the efficacy of epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) in lung adenocarcinoma (LUAD).\n\n\nMETHODS\nThe expression of CXCR1 in NSCLC tissues was assessed by immunohistochemistry. The relationships between CXCR1 expression and clinical-pathological factors were investigated. Concomitantly, the relationship between CXCR1 expression and EGFR-TKI treatment efficacy was investigated. Gene set enrichment analysis (GSEA) was employed for exploration of pathway enrichment, tumor immune estimation resource (TIMER) and gene expression profiling interactive analysis (GEPIA) for the inspection of the interrelationship between infiltration immune cells and CXCR1. After gain-and loss-of-function of CXCR1 in NSCLC cells, qRT-PCR and Western blot were applied to measure the levels of proteins associated with the chemokine pathway (CCL3 and CXCL2) and the JAK/STAT pathway (IL9R, PIAS4 and STAT5A).\n\n\nRESULTS\nCXCR1 significantly correlated with poor prognosis of NSCLC patients. Additionally, CXCR1 limited the clinical efficacy of EGFR-TKIs in advanced LUAD (P = 0.029). In the tumor microenvironment, CXCR1 was positively associated with infiltration levels of immune markers in lung squamous cell carcinoma (LUSC) and LUAD. High expression of CXCR1 was implicated in the NOD-like receptor (NLR), cytokine/cytokine receptor, JAK/STAT and chemokine signaling pathways in LUAD and LUSC. Overexpression of CXCR1 in NSCLC cell lines enhanced expressions of CCL3, CXCL2, IL9R, PIAS4 and STAT5A, while knockdown of CXCR1 lead to repressed expressions of CCL3, CXCL2, IL9R, PIAS4 and STAT5A.\n\n\nCONCLUSION\nCXCR1 is correlated with poor prognosis of NSCLC and affects the efficacy of EGFR-TKIs in LUAD.