Promoter hypomethylation mediated upregulation of MicroRNA-10b-3p targets FOXO3 to promote the progression of esophageal squamous cell carcinoma (ESCC)
Authors: Li-Xin Zhang
Yue Zhao
Zhao Yang
Yi Niu
Guo-Gui Sun
Huan Wang
Wei Wang
Si-Yuan Chen
Xiao-Mei Wei
Yi-Fang Lu
Jia-Rui Yu
Feng-Jin Ye
Peng Gao
Jie Zhang
Guan-Xia Zhu
Mei-Yue Liu
Journal: Journal of Experimental & Clinical Cancer Research (2018)
Discipline: CLINICAL MEDICINE
Keywords: Biomarker; Esophageal squamous cell carcinoma; Hypomethylation; Therapeutic target; microRNAs.
Affiliations: Department of medicine, Tangshan gongren Hospital, Tangshan, China., Department of Radiation Oncology, North China University of Science and Technology Affiliated People's Hospital, Shengli Road, Tangshan, 063000, China., Zhejiang Cancer Research Institute, Zhejiang Cancer Hospital, Hangzhou, 310022, China., Wenzhou Medical College, Wenzhou, China., Department of pathology, North China University of Science and Technology Affiliated People's Hospital, Tangshan, China., Zhejiang Cancer Research Institute, Zhejiang Cancer Hospital, Hangzhou, 310022, China. ., Department of Radiation Oncology, North China University of Science and Technology Affiliated People's Hospital, Shengli Road, Tangshan, 063000, China. .

Abstract:  Background: Esophageal cancer is a high incident cancer worldwide with poor survival and limited therapeutic options. Alterations of microRNAs are common in cancers, and many of these micro RNAs are potential therapeutic and diagnostic targets to treat these cancers. miR-10b-3p located in chromosome region 2q31.1, and its expression is frequently increased in esophageal squamous cell carcinoma (ESCC). However, the biological functions, clinical significance and therapeutic implications of miR-10b-3p in ESCC remain unclear. Methods: The expression levels of miR-10b-3p in ESCC specimens were analyzed by in situ hybridization (ISH) and quantitative reverse transcription polymerase chain reaction (qRT-PCR) assays. Ectopic overexpression of miR-10b-3p in ESCC cells, mouse xenograft model, and metastasis model were used to evaluate the effects of miR-10b-3p on proliferation, and migration of cancer cells. Luciferase reporter assay and Western blot were performed to validate the potential targets of miR-10b-3p after the preliminary screening by computer-aided microarray analysis. Results: We found that miR-10b-3p expression levels were significantly upregulated in the tumor tissues and serum samples of patients with ESCC. The expression levels of miR-10b-3p in both tumor tissues and serum samples were inversely associated with lymph node metastasis and clinical stages. We identified the expression level of miR-10b-3p in ESCC cancer samples as an independent prognostic marker of the overall survival rates of ESCC patients. We found more frequent hypomethylation of the CpG sites located upstream of the miR-10b-3p gene in the ESCC tissues compared with in the adjacent normal tissues, and the DNA methylation status of miR-10b-3p promoter region inversely correlated with the expression levels of miR-10b-3p. Ectopic overexpression of miR-10b-3p promoted cell proliferation, colony formation, migration and invasion in ESCC. While knockdown of miR-10b-3p had the opposite effects, particularly in promoting apoptosis. Mouse xenograft model confirmed that miR-10b-3p functions as a potent oncogenic miRNA in ESCC, which also promoting ESCC metastasis. Mechanistically, we found miR-10b-3p regulated FOXO3 expression by directly binding to the 3'-untranslated region. And systemic delivery of miR-10b-3p antagomir reduced tumor growth and inhibit FOXO3 protein expression in nude mice. Conclusions: Collectively, our findings suggested upregulated expression of miR-10b-3p caused by promoter hypomethylation contributed to the progression of ESCC; Thus, miR-10b-3p is a potentially effective biomarker for ESCC that could have further therapeutic implications. 

Retracted: No

PubPeer comments:
 Figure 6D appears to include a repeated image, marked below in red. ***  , 
 January 21, 2020 In the original publication of this manuscript [1], Fig. 6 contains a repeated image in error (the left image of u2018Migrationu2019 and the left image of u2018Invasionu2019). The misused pictures do not influence the data statistics; all of the original results remain unchanged. The revised Fig. 6 is shown below:  , 
 Additional File Figure S2b  , 
 Dear editor: I have found the mistake. I have corrected it. Thanks for your care* Fig 6D from  miR-4317 suppresses non-small cell lung cancer (NSCLC) by targeting fibroblast growth factor 9 (FGF9) and cyclin D2 (CCND2) ([He et al 2018] ). *[below]* **Fig 3e**.  Two panels overlap and presumably represent the same condition. Could the authors clarify whether that condition is  A973 cells co-transfected with miR-4317 mimic and FGF9 , as in the other paper, or  KYSE150 cells, NC as here? , 
 *[left]* Fig 5c. *[right]* Fig 6D from  DNA methylation-mediated repression of exosomal miR-652-5p expression promotes oesophageal squamous cell carcinoma aggressiveness by targeting PARG and VEGF pathways ([Gao et al 2020] ).  ,