title: Involvement of Numb-mediated HIF-1α inhibition in anti-proliferative effect of PNA-antimiR-182 in trastuzumab-sensitive and -resistant SKBR3 cells.
abstract: Trastuzumab is a humanized monoclonal antibody against the human epidermal growth factor receptor 2 (HER2) that is overexpressed in about 25 % of breast cancer patients. However, primary and/or acquired resistance to trastuzumab develops in most affected persons. In this study, we explored the functional role of miR-182 inhibition with aiming the sensitization of SKBR3 cells to trastuzumab. Cell viability, apoptosis, colony formation, and migration capacities of SKBR3(S) (sensitive) and SKBR3(R) (resistant) cells were assessed to determine the anti-proliferative effects of PNA-antimiR-182. In addition, the expression levels of miR-182, mRNA of FOXO1, and Bim as well as the protein levels of HER2 and Notch1 signaling factors were evaluated by stem-loop RT-qPCR, RT-qPCR, and Western blot, respectively. The results indicated that miR-182 might play a causal role in the mechanism of trastuzumab. In line with that, PNA-antimiR-182 inhibited synergistically the viability of both the sensitive and resistant cell groups. Furthermore, the inhibitory effect of PNA-anitmiR-182 on migration in SKBR3 cells was more than the induction of apoptosis. In addition, PNA-antimiR-182 reduced the levels of NICD, Hes1, HIF-1α, and p-Akt in both cell groups, while it augmented the intracellular content of FOXO1 and Numb suppressor proteins. In other words, PNA-antimiR-182-mediated upregulation of Numb was associated with downregulation of HIF-1α and Hes1. Consequently, downregulation of miR-182 might find therapeutical value for overcoming trastuzumab resistance. Graphical Abstract The crosstalk between HER2 and Notch1 signaling pathway is mediated by miR-182.
authors.affiliation: Institute of Biochemistry and Biophysics, University of Tehran, P. O. Box 13145-1384, Tehran, Iran.
authors.forename: Soraya
authors.initials: S
authors.lastname: Sajadimajd
authors.affiliation: Institute of Biochemistry and Biophysics, University of Tehran, P. O. Box 13145-1384, Tehran, Iran. ryazdan@ut.ac.ir.
authors.forename: Razieh
authors.initials: R
authors.lastname: Yazdanparast
authors.affiliation: Institute of Biochemistry and Biophysics, University of Tehran, P. O. Box 13145-1384, Tehran, Iran.
authors.forename: Sadeghirizi
authors.initials: S
authors.lastname: Akram
mesh_terms: D017209:Apoptosis / Q000187:drug effects; D001943:Breast Neoplasms / Q000188:drug therapy / Q000235:genetics* / Q000473:pathology; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D019008:Drug Resistance, Neoplasm / Q000235:genetics; D005260:Female; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects; D006801:Humans; D051795:Hypoxia-Inducible Factor 1, alpha Subunit / Q000096:biosynthesis / Q000235:genetics*; D008565:Membrane Proteins / Q000096:biosynthesis / Q000235:genetics*; D035683:MicroRNAs / Q000037:antagonists & inhibitors / Q000096:biosynthesis / Q000235:genetics*; D009419:Nerve Tissue Proteins / Q000096:biosynthesis / Q000235:genetics*; D012333:RNA, Messenger / Q000096:biosynthesis; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000235:genetics; D000072056:Transcription Factor HES-1 / Q000096:biosynthesis / Q000235:genetics*; D000068878:Trastuzumab / Q000008:administration & dosage / Q000235:genetics
chemical_list: D051795:Hypoxia-Inducible Factor 1, alpha Subunit; D008565:Membrane Proteins; D035683:MicroRNAs; D009419:Nerve Tissue Proteins; D012333:RNA, Messenger; D018719:Erb-b2 Receptor Tyrosine Kinases; D000072056:Transcription Factor HES-1; D000068878:Trastuzumab; C497442:HIF1A protein, human; C538984:Mirn182 microRNA, human; C113026:NUMB protein, human; C078493:HES1 protein, human
keywords: PNA-antimiR-182; Resistance; SKBR3 cells; Sensitization; Trastuzumab; miR-182