SLURP-1 Controls Growth and Migration of Lung Adenocarcinoma Cells, Forming a Complex With α7-nAChR and PDGFR/EGFR Heterodimer.

Maxim L Bychkov,Viatcheslav N Azev,Zakhar O Shenkarev,Irina A Chulina,Alexander S Paramonov,Ludmila K Baidakova,Sergey G Koshelev,Ekaterina N Lyukmanova,Olga V Shlepova,Mikhail P Kirpichnikov,Mikhail A Shulepko,Dmitrii S Kulbatskii

doi:10.3389/fcell.2021.739391

Maxim L Bychkov, Viatcheslav N Azev + Show 10 more

Open Access

PDF Available

https://doi.org/10.3389/fcell.2021.739391

Copy DOI

Export

Save

Cite

Abstract
Highlights/Summary
Full-Text PDF
Similar Papers

Abstract

Listen

Secreted Ly6/uPAR-related protein 1 (SLURP-1) is a secreted Ly6/uPAR protein that negatively modulates the nicotinic acetylcholine receptor of α7 type (α7-nAChR), participating in control of cancer cell growth. Previously we showed, that a recombinant analogue of human SLURP-1 (rSLURP-1) diminishes the lung adenocarcinoma A549 cell proliferation and abolishes the nicotine-induced growth stimulation. Here, using multiplex immunoassay, we demonstrated a decrease in PTEN and mammalian target of rapamycin (mTOR) kinase phosphorylation in A549 cells upon the rSLURP-1 treatment pointing on down-regulation of the PI3K/AKT/mTOR signaling pathway. Decreased phosphorylation of the platelet-derived growth factor receptor type β (PDGFRβ) and arrest of the A549 cell cycle in the S and G2/M phases without apoptosis induction was also observed. Using a scratch migration assay, inhibition of A549 cell migration under the rSLURP-1 treatment was found. Affinity extraction demonstrated that rSLURP-1 in A549 cells forms a complex not only with α7-nAChR, but also with PDGFRα and epidermal growth factor receptor (EGFR), which are known to be involved in regulation of cancer cell growth and migration and are able to form a heterodimer. Knock-down of the genes encoding α7-nAChR, PDGFRα, and EGFR confirmed the involvement of these receptors in the anti-migration effect of SLURP-1. Thus, SLURP-1 can target the α7-nAChR complexes with PDGFRα and EGFR in the membrane of epithelial cells. Using chimeric proteins with grafted SLURP-1 loops we demonstrated that loop I is the principal active site responsible for the SLURP-1 interaction with α7-nAChR and its antiproliferative effect. Synthetic peptide mimicking the loop I cyclized by a disulfide bond inhibited ACh-evoked current at α7-nAChR, as well as A549 cell proliferation and migration. This synthetic peptide represents a promising prototype of new antitumor drug with the properties close to that of the native SLURP-1 protein.

Highlights

Nicotinic acetylcholine receptors are ligand-gated ion channels that are activated by acetylcholine (ACh) and are involved in regulation of many vital processes in the central and peripheral nervous system, including synaptic transmission and plasticity, neuronal plasticity, memory, cognition, addictive behavior, pain transmission and muscle contraction (Feduccia et al, 2012; Koukouli and Maskos, 2015; Zoli et al, 2018)
We have shown that nicotine stimulates growth of lung carcinoma A549 cells and down-regulates the expression of phosphatase and tensin homolog deleted on chromosome 10 (PTEN), while rSLURP-1 abolishes these negative effects of nicotine (Shulepko et al, 2020b)
We observed a decrease in platelet-derived growth factor receptor type β (PDGFRβ) phosphorylation at the Y751 site upon incubation with rSLURP-1 (Figure 1), which may lead to decrease in phosphorylation of phosphoinositide 3-kinase (PI3K) (Kazlauskas and Cooper, 1990) and AKT (Zhang et al, 2015)

Summary

Introduction

Nicotinic acetylcholine receptors (nAChRs) are ligand-gated ion channels that are activated by acetylcholine (ACh) and are involved in regulation of many vital processes in the central and peripheral nervous system, including synaptic transmission and plasticity, neuronal plasticity, memory, cognition, addictive behavior, pain transmission and muscle contraction (Feduccia et al, 2012; Koukouli and Maskos, 2015; Zoli et al, 2018). A lot of data on the expression of nAChRs in non-neuronal cells, and on their participation in regulation of epithelial cell homeostasis and the immune system were published (Wessler and Kirkpatrick, 2009; Kulbatskii et al, 2018; Zoli et al, 2018). Nicotinic acetylcholine receptor of α7 type (α7-nAChR) is one of the most widespread type of nAChRs expressed in epithelial and immune cells (Zoli et al, 2018). The nicotine signaling in lung cancer cells can be enhanced by mitogenic receptor tyrosine kinases (RTKs) activation due to formation of heterocomplexes between α7-nAChRs and some RTKs, such as epidermal growth factor receptor (EGFR) (Chernyavsky et al, 2015). Along with the cell membrane, α7-nAChRs are located on the mitochondrial membrane, where they can inhibit a mitochondrial membrane pore formation and apoptosis induction (Gergalova et al, 2012; Kalashnyk et al, 2012)

Methods

Results

Conclusion