Related Experiment Video
Updated: Feb 10, 2026
Generation and Isolation of Cell Cycle-arrested Cells with Complex Karyotypes
Published on: April 13, 2018
Knockdown of annexin A5 restores gefitinib sensitivity by promoting G2/M cell cycle arrest
Jian Zhou1,2, Meijia Chang1,2, Jing Li1,2
1Department of Pulmonary Medicine, Zhongshan Hospital, Fudan University, Shanghai, China.
Background:
Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors, including gefitinib, are first-line drugs against advanced non-small cell lung cancer with activating EGFR mutations. However, the development of resistance to such drugs is a major clinical challenge.
Methods:
The role of annexin A5 in resistance to EGFR tyrosine kinase inhibitors was investigated by qPCR and western blot of relevant molecules, by CCK8 and EdU assay of cell proliferation and viability, by annexin V/propidium iodide assay of apoptosis and cell cycle distribution, by JC-1 assay of mitochondrial integrity, and by xenograft assay of tumorigenicity.
Results:
We found that annexin A5 is upregulated in gefitinib-resistant cell lines, as well as in clinical specimens resistant to EGFR tyrosine kinase inhibitors. Accordingly, knockdown of the gene from gefitinib-resistant cells restores gefitinib sensitivity in vitro and in vivo by downregulating polo-like kinase 1 signal pathway, thereby inducing mitochondrial damage, caspase activation, cell cycle arrest at G2/M, and, finally, apoptosis.
Conclusions:
The data indicate that annexin A5 confers gefitinib resistance in lung cancer by inhibiting apoptosis and G2/M cell cycle arrest, and is thus a potential therapeutic target in non-small cell lung cancers resistant to EGFR tyrosine kinase inhibitors.
Insights
Annexin A5 promotes resistance to epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors in lung cancer. Inhibiting annexin A5 can restore sensitivity to gefitinib by promoting apoptosis and cell cycle arrest.
Area of Science:
- Oncology
- Molecular Biology
- Pharmacology
Background:
- Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) are first-line treatments for advanced non-small cell lung cancer (NSCLC) with activating EGFR mutations.
- Acquired resistance to EGFR TKIs like gefitinib is a significant clinical obstacle in NSCLC treatment.
Purpose of the Study:
- To investigate the role of annexin A5 in the development of resistance to EGFR TKIs.
- To explore annexin A5 as a potential therapeutic target for overcoming TKI resistance in NSCLC.
Main Methods:
- Quantitative PCR (qPCR) and Western blot to assess molecule expression.
- Cell Counting Kit-8 (CCK8) and EdU assays for cell proliferation and viability.
- Annexin V/propidium iodide staining for apoptosis and cell cycle analysis.
- JC-1 assay for mitochondrial integrity and xenograft assays for tumorigenicity.
Main Results:
- Annexin A5 was found to be upregulated in gefitinib-resistant NSCLC cell lines and clinical specimens.
- Knockdown of annexin A5 in resistant cells restored gefitinib sensitivity both in vitro and in vivo.
- Annexin A5 downregulation led to polo-like kinase 1 pathway inhibition, mitochondrial damage, caspase activation, G2/M cell cycle arrest, and apoptosis.
Conclusions:
- Annexin A5 contributes to gefitinib resistance in lung cancer by inhibiting apoptosis and G2/M cell cycle arrest.
- Annexin A5 represents a promising therapeutic target for overcoming resistance to EGFR TKIs in NSCLC.
More Related Videos
12:02Studying Cell Cycle-regulated Gene Expression by Two Complementary Cell Synchronization Protocols
Published on: June 6, 2017
08:33Combining Mitotic Cell Synchronization and High Resolution Confocal Microscopy to Study the Role of Multifunctional Cell Cycle Proteins During Mitosis
Published on: December 5, 2017
Related Concept Videos
01:19Restorative Care
01:04What is the Cell Cycle?
00:56What is the Cell Cycle?
02:40The Eukaryotic Promoter Region
01:28The Cell Cycle Control System
Cyclins and cyclin-dependent kinases (Cdks) are the primary cell cycle regulators and...
02:11The Cell Cycle Control System