MicroRNA-326 inhibits melanoma progression by targeting KRAS and suppressing the AKT and ERK signalling pathways
Authors: Jing Zhang
Xiaoyun Zhang
Kang Kang
Zhao Chen
Journal: Oncology Reports (2017)
Discipline: CLINICAL MEDICINE
Keywords: Melanoma; microRNA; miR-326; tumourigenesis; KRAS
Affiliations: Department of Dermatology, Tangshan City Workers' Hospital, Tangshan, Hebei 063000, P.R. China.

Abstract:  Melanoma is the seventh most common malignancy in females and the fifth most common cancer in males worldwide. An increasing number of studies have reported that microRNA (miRNA) dysregulation is frequently observed in various types of human cancers, including melanoma. Abnormally expressed miRNAs play an important role in melanoma formation and progression by serving as potential biomarkers and therapeutic targets. Recently, miRNA-326 (miR-326) has been reported to be differentially expressed in various types of tissues and play important roles in tumourigenesis and tumour development. However, the expression levels, biological roles and underlying mechanisms of miR-326 in melanoma remain unknown. In the present study, we demonstrated that miR-326 was significantly downregulated in melanoma tissues and cell lines. Functional assays revealed that the enforced expression of miR-326 suppressed melanoma cell proliferation and invasion and increased cell apoptosis in vitro. Using bioinformatic analysis, Kirsten rat sarcoma viral oncogene homolog (KRAS) was predicted as a potential target of miR-326. Luciferase reporter assay confirmed that miR-326 could directly target the 3'-untranslated region of KRAS. In addition, reverse transcription-quantitative polymerase chain reaction and western blot analysis revealed that miR-326 upregulation decreased the KRAS expression in melanoma cells at both the mRNA and protein level. Furthermore, KRAS was upregulated in melanoma tissues and inversely correlated with miR-326 expression. In addition, the KRAS knockdown phenocopied the tumour-suppressing effects of miR-326 overexpression on melanoma cells. The restoration of the expression of KRAS markedly reversed the antitumour effects induced by miR-326 overexpression in melanoma cells. Further experiments indicated that miR-326 inactivated the AKT and ERK signalling pathways in melanoma. Collectively, these results revealed that miR-326 serves as a tumour suppressor in melanoma by targeting KRAS and regulating the AKT and ERK signalling pathways, indicating that miR-326 may be a promising therapeutic target for melanoma patients. 

Retracted: No

PubPeer comments:
 Plagiarising a comment by Elisabeth Bik: ----------------------------------------- This paper belongs to a set of over 400 papers (as per February 2020) that share very similar Western blots with tadpole-like shaped bands, the same background pattern, and striking similarities in title structures, paper layout, bar graph design, and - in a subset - flow cytometry panels. Despite these similarities, these papers are authored by researchers from different departments and institutes, with almost no overlap in authors. The list of these papers is available here: https: docs.google.com spreadsheets d 1KXqTAyl4j-jVorFPMD2XRpr76LcIKJ0CVyIvRj0exYQ edit?usp=sharing A more detailed description of this set of papers, suspected to all be generated by a common source, a paper mill , can be found here: - https: forbetterscience.com 2020 01 24 the-full-service-paper-mill-and-its-chinese-customers (January 2020) - https: scienceintegritydigest.com 2020 02 21 the-tadpole-paper-mill (February 2020) The same paper mill has been described in these papers: - Jana Christopher - Systematic fabrication of scientific images revealed - FEBS Letters (2018) - https: febs.onlinelibrary.wiley.com doi full 10.1002 1873-3468.13201 - Jennifer A Byrne and Jana Christopher - Digital magic, or the dark arts of the 21st centuryu2014how can journals and peer reviewers detect manuscripts and publications from paper mills? - FEBS Letters (2020) - https: febs.onlinelibrary.wiley.com doi full 10.1002 1873-3468.13747 ------------------------------------------------ In this instance, the stylised Western Blots take the form of airbrushed dog-bones rather than the tadpole form more usual in this oeuvre. Here, Fig 6. ![file] ,