Hsp90 inhibitor gedunin causes apoptosis in A549 lung cancer cells by disrupting Hsp90:Beclin-1:Bcl-2 interaction and downregulating autophagy

Copyright © 2020 Elsevier Inc. All rights reserved..

AIMS: Hsp90 is regarded as an important therapeutic target in cancer treatment. Client proteins of Hsp90 like Beclin-1, PI3K, and AKT, are associated with tumor development, poor prognosis, and resistance to cancer therapies. This study aims to analyze the role of Gedunin, an Hsp-90 inhibitor, in mediation of crosstalk between apoptosis and autophagy by targeting Beclin-1:Bcl-2 interaction, and ER stress.

MAIN METHODS: A549 cells were treated with different concentrations of gedunin, and inhibitory rate was evaluated by MTT assay. Effect of gedunin on generation of reactive oxygen species, mitochondrial membrane potential, and chromatin condensation was studied by staining methods like DCFH-DA, MitoTracker, and DAPI. Expression of EGFR, PIK3CA, AKT, marker genes for apoptosis and autophagy were studied using semi-quantitative RT-PCR. Interaction study of Hsp90:Beclin-1:Bcl-2 was done by immunoprecipitation analysis. Protein expression of autophagy and apoptosis markers along with Grp78, Hsp70, and Hsp90 was analyzed by immunoblotting.

KEY FINDINGS: Gedunin exerts cytotoxic effects, causes increase in ROS generation, downregulates mitochondrial membrane potential and induces loss in DNA integrity. mRNA expression analysis revealed that gedunin sensitized A549 cells towards apoptosis by downregulating EGFR, PIK3CA, AKT, and autophagy. Gedunin also inhibited interaction between Hsp90:Beclin-1:Bcl-2, leading to downregulation of autophagy (Beclin-1, Atg5-12 complex, and LC3) and antiapoptotic protein Bcl-2, which may result in ER stress-induced apoptosis. Moreover, Hsp90 inhibition by gedunin did not cause upregulation of Hsp70 expression.

SIGNIFICANCE: Gedunin induces apoptosis in lung cancer cells by disrupting Hsp90:Beclin-1:Bcl-2 interaction and autophagy downregulation, thus making gedunin a good drug lead for targeting lung cancer.

Medienart:

E-Artikel

Erscheinungsjahr:

2020

Erschienen:

2020

Enthalten in:

Zur Gesamtaufnahme - volume:256

Enthalten in:

Life sciences - 256(2020) vom: 01. Sept., Seite 118000

Sprache:

Englisch

Beteiligte Personen:

Hasan, Adria [VerfasserIn]
Haque, Ejazul [VerfasserIn]
Hameed, Rohil [VerfasserIn]
Maier, Paul N [VerfasserIn]
Irfan, Safia [VerfasserIn]
Kamil, Mohd [VerfasserIn]
Nazir, Aamir [VerfasserIn]
Mir, Snober S [VerfasserIn]

Links:

Volltext

Themen:

2753-30-2
Antineoplastic Agents, Phytogenic
Apoptosis
Autophagy
BCL2 protein, human
Beclin-1
ER stress
Endoplasmic Reticulum Chaperone BiP
Gedunin
HSP90 Heat-Shock Proteins
HSPA5 protein, human
Hsp90
Journal Article
Limonins
Proto-Oncogene Proteins c-bcl-2
Reactive Oxygen Species

Anmerkungen:

Date Completed 31.08.2020

Date Revised 04.12.2021

published: Print-Electronic

Citation Status MEDLINE

doi:

10.1016/j.lfs.2020.118000

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM311635768