The clinical synergistic antitumor efficacy of Lienal Polypeptide combined with EGFR-TKIs for advanced NSCLC

Abstract Purpose: EGFR-TKIs are the first-line therapy for advanced NSCLC harboring EGFR-sensitive mutations. A robust immunity is an essential foundation for patients to tolerate continuous drug treatments. Lienal polypeptide (LP) is an immunomodulator widely applied to regulate immunity in clinical practice. Nevertheless, its potential impact on EGFR-TKIs therapy has not been illustrated. This study aimed to explore the immunomodulatory and antitumor efficacy of LP in combination with EGFR-TKIs threapy in advanced NSCLC.Patients and methods: Retrospective analysis on variation of lymphocytes in 106 NSCLC patients after EGFR-TKIs combined with LP treatment was performed. Proliferation experiment, transwell and wound healing assays were performed in PC9-GR cells to estimate influence of LP on tumor proliferation, invasion and migrati n in vitro . Flow cytometry was performed to detect cell apoptosis and cell cycle. The expression of p-EGFR and EGFR were detected by Western blot to investigate antitumor effect of LP.Results: The levels of CD3 + , CD4 + T cells and the CD4 + /CD8 + ratio were higher in NSCLC patients treated with Gefitinib in conjunction with LP. Gefitinib combined with LP inhibited tumor invasion and migration, triggered G0/G1 phase arrest to block cellular proliferation and promote cell apoptosis in vitro. Furthermore, the expression of p-EGFR was decreased after Gefitinib-combining-LP treatment.Conclusions: LP had a synergistic anticancer effect with EGFR-TKIs in NSCLC. LP in combination with EGFR-TKIs therapy has clinical curative effect in treatment of advanced NSCLC with EGFR driving mutations, can effectively enhance physical immunity and resensitize drug-resistant cells to EGFR-TKIs, which has a certain clinical application value.