Chemosensitizing activity of peptide from Lentinus squarrosulus (Mont.) on cisplatin-induced apoptosis in human lung cancer cells

Hnin Ei Ei Khine,Narumon Phaonakrop,Eakachai Prompetchara,Pithi Chanvorachote,Gea Abigail Uy Ecoy,Sittiruk Roytrakul,Natapol Pornputtapong,Chatchai Chaotham

doi:10.1038/s41598-021-83606-1

Abstract

The limitations of cisplatin, a standard chemotherapy for lung cancer, have been documented with serious adverse effects and drug resistance. To address the need for novel therapy, this study firstly reveals the potential of peptide from Lentinus squarrosulus (Mont.) as a chemotherapeutic adjuvant for cisplatin treatment. The purified peptide from L. squarrosulus aqueous extracts was obtained after eluting with 0.4 M NaCl through FPLC equipped with anion exchange column. Preincubation for 24 h with 5 µg/mL of the peptide at prior to treatment with 5 µM cisplatin significantly diminished %cell viability in various human lung cancer cells but not in human dermal papilla and proximal renal cells. Flow cytometry indicated the augmentation of cisplatin-induced apoptosis in lung cancer cells pretreated with peptide from L. squarrosulus. Preculture with the peptide dramatically inhibited colony formation in lung cancer cells derived after cisplatin treatment. Strong suppression on integrin-mediated survival was evidenced with the diminution of integrins (β1, β3, β5, α5, αV) and down-stream signals (p-FAK/FAK, p-Src/Src, p-Akt/Akt) consequence with alteration of p53, Bax, Blc-2 and Mcl-1 in cisplatin-treated lung cancer cells preincubated with peptide from L. squarrosulus. These results support the development of L. squarrosulus peptide as a novel combined chemotherapy with cisplatin for lung cancer treatment.

Highlights

Despite several decades of intensive research, lung cancer remains to be a global health burden and the leading cause of cancer-related death[1]
The peptide pellets were precipitated out from the homogenized aqueous solution of L. squarrosulus fruiting bodies by adding 40–80% (NH4)2SO4. These crude peptide extracts were resolubilized in phosphate buffer solution (PBS) and further purified through fast protein liquid chromatography (FPLC) coupled with anion exchange column
The diminished levels of β1, β3, β5, α5 and αV integrins, which are up-stream regulatory molecules, were time-dependently observed following the treatment of L. squarrosulus peptide (Fig. 4e,f). These results indicated that L. squarrosulus peptide at non-toxic concentration effectively alters apoptosis and integrin-mediating survival signals in human lung cancer cells

Summary

Introduction

Despite several decades of intensive research, lung cancer remains to be a global health burden and the leading cause of cancer-related death[1]. The aggressive features and distinct mechanisms observed in lung cancer cells lead to chemotherapeutic resistance and treatment failure[5,6]. The upregulation or overexpression of the anti-apoptosis protein, Bcl-2 (B-cell lymphoma 2), is related to the reduced susceptibility to cisplatin-induced apoptosis[10,13]. The modulation of Bcl-2 family proteins to reverse cisplatin resistance is worth investigating further Another strategy is the regulation of tumor suppressor p53 which has been a reported mechanism of several natural chemosensitizers[9]. This study is the first to investigate the novel chemosensitizing activity of the peptide extracted from L. squarrosulus to enhance cisplatin efficacy without causing toxicity to non-cancer cells. The investigation seeks to provide information which could encourage the further development of chemotherapeutic adjuvants with good safety profile for lung cancer treatment

Methods

Results

Conclusion