FOXM1-activated IGF2BP3 promotes cell malignant phenotypes and M2 macrophage polarization in hepatocellular carcinoma by inhibiting ferroptosis via stabilizing RRM2 mRNA in an m6A-dependent manner

Heng Gao; Lei Shi; Jinfeng Liu; Yingren Zhao; Fenjing Du; Yingli He; Xin Yang; Ning Song; Juan Wen; Gezhi Zheng

doi:10.1007/s11010-024-05170-2

FOXM1-activated IGF2BP3 promotes cell malignant phenotypes and M2 macrophage polarization in hepatocellular carcinoma by inhibiting ferroptosis via stabilizing RRM2 mRNA in an m6A-dependent manner

Mol Cell Biochem. 2024 Dec 4. doi: 10.1007/s11010-024-05170-2. Online ahead of print.

Authors

Heng Gao^{1

2}, Lei Shi¹, Jinfeng Liu¹, Yingren Zhao¹, Fenjing Du¹, Yingli He¹, Xin Yang¹, Ning Song¹, Juan Wen¹, Gezhi Zheng³

Affiliations

¹ Department of Infectious Diseases, The First Affiliated Hospital of Xi'an Jiaotong University, No. 277, Yanta West Road, Xi'an, 710061, China.
² Xi'an Health School, Xi'an, 710054, China.
³ Department of Infectious Diseases, The First Affiliated Hospital of Xi'an Jiaotong University, No. 277, Yanta West Road, Xi'an, 710061, China. zgz84326@163.com.

PMID: 39630361
DOI: 10.1007/s11010-024-05170-2

Abstract

Background: Ferroptosis has a crucial role in human carcinogenesis. N6-methyladenosine (m6A) reader insulin-like growth factor 2 mRNA-binding protein 3 (IGF2BP3) suppresses ferroptosis of hepatocellular carcinoma (HCC) cells. Here, we examined the effects and molecular determinants of IGF2BP3-mediated ferroptosis on malignant behaviors of HCC cells.

Methods: Ferroptosis was evaluated by measuring the levels of malondialdehyde (MDA), glutathione (GSH), reactive oxygen species (ROS), and lipid ROS. HCC cell malignant phenotypes were evaluated by colony formation assay, wound healing assay, and transwell invasion assay. The CD206⁺ M2-like macrophages were assessed by flow cytometry. m6A RNA immunoprecipitation (MeRIP) was applied to assess the m6A modification of ribonucleotide reductase regulatory subunit M2 (RRM2). RNA immunoprecipitation (RIP) assay was performed to evaluate the interaction of IGF2BP3 and RRM2. Chromatin immunoprecipitation (ChIP) and dual-luciferase reporter assays were conducted to confirm the interaction between forkhead box M1 (FOXM1) and IGF2BP3.

Results: Human HCC tumors showed increased expression of IGF2BP3 compared with adjacent normal tissues. Disruption of IGF2BP3 promoted cell ferroptosis. Moreover, disruption of IGF2BP3 hindered HCC cell growth, invasiveness, and motility and impeded THP1-derived macrophage M2 polarization and migration by inducing ferroptosis. Additionally, IGF2BP3 disruption repressed xenograft growth in vivo. Mechanistically, IGF2BP3 enhanced RRM2 mRNA stability and elevated its protein expression by reading its m6A modification. Overexpression of RRM2 reversed sh-IGF2BP3-mediated ferroptosis and weakened sh-IGF2BP3-mediated suppression of HCC cell malignant phenotypes and macrophage M2 polarization. Furthermore, IGF2BP3 was a downstream target of FOXM1, and knockdown of FOXM1 induced ferroptosis and inhibited cell malignant phenotypes by downregulating IGF2BP3.

Conclusion: FOXM1-induced IGF2BP3 upregulation promotes HCC cell malignant behaviors and macrophages M2 polarization by repressing ferroptosis via m6A-dependent regulation of RRM2 mRNA. Targeting FOXM1/IGF2BP3/RRM2 to enhance ferroptosis might be exploited as a potent therapeutic strategy for HCC.

Keywords: FOXM1; Ferroptosis; Hepatocellular carcinoma; IGF2BP3; RRM2; m6A.