Mechanism of metformin inhibiting malignant progression of hepatocellular carcinoma by promoting degradation of aldo-keto reductase AKR1C3
10.11665/j.issn.1000-5048.2025030703
- VernacularTitle:二甲双胍通过促进醛酮还原酶AKR1C3降解抑制肝细胞癌恶性进展的机制研究
- Author:
Lei QI
1
;
Jingyi HUA
;
Qiuju FENG
;
Di PAN
;
Lingxiang LIU
;
Li ZHAO
Author Information
1. 中国药科大学基础医学与临床药学学院, 南京 211198;贵州医科大学药学院, 贵阳 550004;南京医科大学第一附属医院, 南京 210029;神经与肿瘤药物研发全国重点实验室, 南京 210023
- Publication Type:Journal Article 期刊文章
- Keywords:
hepatocellular carcinoma;
metformin;
AKR1C3;
autophagy
- From:
Journal of China Pharmaceutical University
2025;56(5):572-582
- CountryChina
- Language:Chinese
-
Abstract:
This study aimed to elucidate the mechanism of action of metformin (MET) in inhibiting the malignant progression of hepatocellular carcinoma (HCC) by regulating the degradation of aldo-keto reductase family 1 member C3 (AKR1C3). The correlation between the sensitivity of different hepatocellular carcinoma cell lines to MET and their basal expression levels of AKR1C3 was firstly evaluated. MET was found to significantly reduce the level and accelerate the degradation rate of AKR1C3 protein by Western blot. The interaction between MET and AKR1C3 protein was confirmed by cellular thermal shift assay (CETSA). Proteasome inhibitor MG132 and the lysosomal inhibitor chloroquine (CQ) were used to screen the degradation pathway, and confirm, in combination with the HBSS starvation-induced autophagy model, that MET mediated the degradation of AKR1C3 through the autophagy lysosome pathway. Ubiquitylation assay showed that MET specifically enhanced the K63-linked polyubiquitylation modification of AKR1C3. Sequestosome 1 (SQSTM1/p62) knockdown, immunoprecipitation, and immunofluorescence co-localization analyses confirmed that the autophagy receptor p62 plays a key role in mediating MET-induced degradation of AKR1C3. The adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK) inhibitor compound C was used to demonstrate that the regulatory effect of MET on AKR1C3 is independent of the classical AMPK signaling pathway. The experimental results showed that metformin promoted the ubiquitination modification of AKR1C3 by targeting AKR1C3, enhanced the binding of AKR1C3 to autophagy receptor p62, then degraded the AKR1C3 protein through selective autophagy-like pathway, and ultimately inhibited the malignant phenotypes of hepatocellular carcinoma cells, which is a regulatory mechanism free of the classical AMPK activation pathway of metformin.
