title: MiR-331-3p inhibits proliferation and promotes apoptosis by targeting HER2 through the PI3K/Akt and ERK1/2 pathways in colorectal cancer.
abstract: MicroRNAs (miRNAs) regulate cell proliferation, apoptosis and carcinogenesis by targeting related mRNAs in different types of cancer. miR-331-3p has been found to regulate the development and progression of various types of cancer cells. However, little research has been conducted on the role of miR-331-3p in colorectal cancer (CRC). The present study aimed to explore the function of miR-331-3p in CRC. We found that miR-331-3p was significantly downregulated in CRC tissues and cells compared to the level in healthy colon tissues and cells. Overexpression of miR-331-3p by transfection with pre‑miR-331-3p inhibited cell proliferation, promoted apoptosis and activated caspase-3. Furthermore, the protein expression level of apoptosis-related protein Bcl-2 was downregulated and Bax was upregulated by pre‑miR‑331-3p. Downregulation of the expression of miR-331-3p by transfection with AS-miR-331-3p had the opposite effect. Moreover, we found that HER2 was overexpressed in the CRC cell lines, and the expression level of HER2 was negatively regulated by miR‑331-3p. Additionally, knockdown of HER2 inhibited cell proliferation and phosphorylation of Akt and ERK1/2 induced by AS-miR-331-3p. Overall, we identified that miR‑331-3p is underexpressed in CRC and contributes to cell growth regulation by targeting HER2 through activating the PI3K/Akt and ERK1/2 signaling pathways.
authors.affiliation: Department of Radiotherapy, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi 710061, P.R. China.
authors.forename: Dongli
authors.initials: D
authors.lastname: Zhao
authors.affiliation: Department of Pathology, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi 710061, P.R. China.
authors.forename: Yanxia
authors.initials: Y
authors.lastname: Sui
authors.affiliation: Department of Radiotherapy, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi 710061, P.R. China.
authors.forename: Xiaoqiang
authors.initials: X
authors.lastname: Zheng
mesh_terms: D000230:Adenocarcinoma / Q000235:genetics* / Q000473:pathology; D017209:Apoptosis / Q000502:physiology; D053148:Caspase 3 / Q000378:metabolism; D002455:Cell Division; D045744:Cell Line, Tumor; D015179:Colorectal Neoplasms / Q000235:genetics* / Q000473:pathology; D004789:Enzyme Activation / Q000235:genetics; D015972:Gene Expression Regulation, Neoplastic / Q000235:genetics*; D019254:Genes, bcl-2; D018734:Genes, erbB-2; D006801:Humans; D020935:MAP Kinase Signaling System / Q000235:genetics; D035683:MicroRNAs / Q000096:biosynthesis / Q000235:genetics*; D009363:Neoplasm Proteins / Q000096:biosynthesis / Q000235:genetics / Q000502:physiology; D019869:Phosphatidylinositol 3-Kinases / Q000502:physiology; D010766:Phosphorylation / Q000235:genetics; D011499:Protein Processing, Post-Translational / Q000235:genetics; D051057:Proto-Oncogene Proteins c-akt / Q000502:physiology; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000235:genetics; D012322:RNA Precursors / Q000235:genetics; D016372:RNA, Antisense / Q000235:genetics; D012334:RNA, Neoplasm / Q000096:biosynthesis / Q000235:genetics*; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000096:biosynthesis / Q000502:physiology*; D015398:Signal Transduction / Q000235:genetics*; D014162:Transfection; D051028:bcl-2-Associated X Protein / Q000096:biosynthesis / Q000235:genetics
chemical_list: D053148:Caspase 3; D035683:MicroRNAs; D009363:Neoplasm Proteins; D019869:Phosphatidylinositol 3-Kinases; D051057:Proto-Oncogene Proteins c-akt; D019253:Proto-Oncogene Proteins c-bcl-2; D012322:RNA Precursors; D016372:RNA, Antisense; D012334:RNA, Neoplasm; D018719:Erb-b2 Receptor Tyrosine Kinases; D051028:bcl-2-Associated X Protein; C494826:BAX protein, human; C544460:MIRN331 microRNA, human; C508053:ERBB2 protein, human; C494918:AKT1 protein, human; C505407:CASP3 protein, human