Elevated microRNA-7 inhibits proliferation and tumor angiogenesis and promotes apoptosis of gastric cancer cells via repression of Raf-1
Authors: Jing Lin
Shasha Liao
Wanting Zeng
E Li
Zewa Liu
Xiaohua Wu
Journal: Cell Cycle (2020)
Discipline: MOLECULAR BIOLOGY & GENETICS
Keywords: MicroRNA-7; Raf-1; apoptosis; gastric cancer; invasion
Affiliations: Oncology Department, The First Affiliated Hospital of Shantou University Medical College, Shantou, China., Oncology Department, Shantou Longhu People's Hospital , Shantou, Guangdong, China., MSci Applied Medical Science, Division of Medicine, University College London, London, WC1E 6BT, United Kingdom.

Abstract:  Objective: Since the essential involvement of microRNAs (miRNAs) in the development and progression of GC, the study was for the exploration of the value of microRNA-7 (miR-7) in the evaluation of neoadjuvant chemotherapy for gastric cancer (GC) and its effects on apoptosis, proliferation and angiogenesis of GC. Methods: miR-7 expression in serum of GC patients before and after neoadjuvant chemotherapy were detected to explore its role in neoadjuvant chemotherapy of GC. The GC cells were transfected with miR-7 mimics/inhibitors, or siRNA-Raf-1 to figure out their roles in proliferation, migration, invasion, cycle distribution and apoptosis. Tumor xenograft was conducted to test tumor growth. Microvessel density (MVD) in tumors was tested by immunohistochemical staining. Results: miR-7 expression in serum of GC patients was lower than that of healthy controls while it was elevated after neoadjuvant chemotherapy. Moreover, higher miR-7 expression was exhibited in chemotherapy-effective patients rather than chemotherapy-ineffective patients (P &lt; 0.01). miR-7 expression in serum was connected with tumor size, degree of differentiation, TNM stage and lymphatic metastasis.miR-7 was decreased and Raf-1 was elevated in GC cells (both P &lt; 0.05). Elevated miR-7 or declined Raf-1 inhibited GC cell migration, proliferation and invasion, cell cycle entry, xenografted tumor growth and MVD and stimulated apoptosis (all P &lt; 0.05). Down-regulated Raf-1 reversed the impacts of miR-7 knockdown on GC cells (all P &lt; 0.05). Conclusion: Our study highlights that elevated miR-27a indicates the good efficacy of neoadjuvant chemotherapy in GC and miR-7 targets Raf-1 to suppress tumor development and angiogenesis of GC cells. 

Retracted: No

PubPeer comments:
 Fig. 5g has a reused image ![] , 
 ResearchGate informs me that the first author has been corresponding author on four papers, with a different disposable email address each time: LLLinjing2019@163.com, but also jinglinab123@163.com, linjingst@tom.com and drdingwei66@163.com (!). Is there any special reason for this complication? , 
 Expression of Concern, [1 September 2021] .  After publication of this article, questions about the scientific integrity of the article content were brought to the Publisher and Editoru2019s attention. We have reached out to the authors requesting that they supply information that would confirm the articleu2019s integrity, but the authors have not responded to our queries within the requested timeframe. Therefore, as we continue to work through the issues raised, we advise readers to interpret the information presented in the article with due caution. The authors have been notified about this Expression of Concern. ---------------------------- I urge the editors to include the problematic cell-cycle analyses of Fig 3c d in their inquiry. ![file] ,