MiR-552-3p promotes malignant progression of gallbladder carcinoma by reactivating the Akt/β-catenin signaling pathway due to inhibition of the tumor suppressor gene RGMA

Fengliang Song; Zhao Yang; Liang Li; Yanping Wei; Xuewu Tang; Shuowu Liu; Miao Yu; Jin Chen; Suyang Wang; Jingbo Fu; Kecheng Zhang; Pinghua Yang; Xinwei Yang; Zhong Chen; Baohua Zhang; Hongyang Wang

doi:10.21037/atm-21-2013

MiR-552-3p promotes malignant progression of gallbladder carcinoma by reactivating the Akt/β-catenin signaling pathway due to inhibition of the tumor suppressor gene RGMA

Ann Transl Med. 2021 Sep;9(17):1374. doi: 10.21037/atm-21-2013.

Authors

Fengliang Song^{1

2}, Zhao Yang³, Liang Li^{1

4}, Yanping Wei^{1

4}, Xuewu Tang^{1

5}, Shuowu Liu^{1

4}, Miao Yu^{1

4}, Jin Chen^{1

4}, Suyang Wang^{1

4}, Jingbo Fu^{1

4}, Kecheng Zhang⁶, Pinghua Yang⁶, Xinwei Yang⁶, Zhong Chen², Baohua Zhang⁶, Hongyang Wang^{1

4

7}

Affiliations

¹ International Co-operation Laboratory on Signal Transduction, Eastern Hepato-biliary Surgery Institute, Second Military Medical University, Shanghai, China.
² Department of General Surgery, The Affiliated Hospital of Nantong University, Nantong, China.
³ Department of Hepatic Surgery II, Eastern Hepatobiliary Surgery Hospital, Second Military Medical University, Shanghai, China.
⁴ National Center for Liver Cancer, Shanghai, China.
⁵ Zhongda Hospital, School of Medicine, Southeast University, Nanjing, China.
⁶ Department of Biliary Tract Surgery, Eastern Hepatobiliary Surgery Hospital, Second Military Medical University, Shanghai, China.
⁷ National Laboratory for Oncogenes and Related Genes, Cancer Institute, Renji Hospital, Shanghai Jiao Tong University, Shanghai, China.

Abstract

Background: Gallbladder carcinoma (GBC) remains a highly lethal disease worldwide. MiR-552 family members promote the malignant progression of a variety of digestive system tumors, but the role of miR-552-3p in GBC has not been elucidated. miR-552-3p was predicted to target the 3'-untranslated region (3'UTR) of the mRNA for the tumor suppressor gene "repulsive guidance molecule BMP co-receptor a" (RGMA). The aim of the present study was to clarify the roles and mechanisms of miR-552-3p targeting RGMA in the malignant progression of GBC.

Methods: In vitro: expression of miR-552-3p was detected by real-time quantitative PCR (qRT-PCR) in tumor and non-tumor adjacent tissues (NATs). Lentivirus-miR-552-3p was employed to knockdown this miRNA in GBC cell lines. Stem cell-related transcription factors and markers were assessed by qRT-PCR. Cell Counting Kit-8 (CCK-8), sphere formation and transwell assays were used to determine the malignant phenotypes of GBC cells. Targeting the 3'UTR of RGMA by miR-552-3p was verified by integrated analysis including bioinformatics prediction, luciferase assays, measures of changes of gene expression and rescue experiments. In vivo: mouse models of subcutaneous tumors and lung metastases were established to observe the effect of miR-552-3p on tumorigenesis and organ metastasis, respectively.

Results: MiR-552-3p was abnormally highly expressed in GBC tissues and cancer stem cells. Interference with miR-552-3p in SGC-996 and GBC-SD cells significantly inhibited GBC stem cell expansion. Reciprocally, miR-552-3p promoted GBC cell proliferation, migration and invasion both in vitro and in vivo; hence, interference with this miRNA impeded the malignant progression of GBC. Furthermore, the important tumor suppressor gene RGMA was identified as a target of miR-552-3p. The effects of miR-552-3p on cell proliferation and metastasis were abrogated or enhanced by gain or loss of RGMA function, respectively. Mechanistically, miR-552-3p promoted GBC progression by reactivating the Akt/β-catenin pathway and epithelial-mesenchymal transformation (EMT). Clinically, miR-552-3p correlated with multi-malignant characteristics of GBC and acted as a prognostic marker for GBC outcome.

Conclusions: MiR-552-3p promotes the malignant progression of GBC by inhibiting the mRNA of the tumor suppressor gene RGMA, resulting in reactivation of the Akt/β-catenin signaling pathway.

Keywords: Gallbladder carcinoma (GBC); epithelial-mesenchymal transformation (EMT); miR-552-3p; repulsive guidance molecule BMP co-receptor a (RGMA); stemness.