RESUMO
Breast cancer (BC) is a highly aggressive tumour and one of the women's leading causes of cancer-related deaths in worldwide. MiR-375 overexpressed in BC cells, and its biological relevance is largely unknown. Here in, we explored the function of miR-375 in BC. MicroRNA-375 targets were predicted by online target prediction tools and found that HOXA5 is one of the potential targets. MTT assay was employed to assess the effect of miR-375 on cell proliferation, where migration and invasion transwell assays were applied to detect cell migratory and invasive ability. Besides, relative expression of miR-375 and HOXA5 was measured in BC and HEK-293 cells, and its downstream gene target expressions were evaluated by qRT-PCR and western blot. In this study, we found that miR-375 expression was higher in BC cell lines than in the HEK-293 cell line, whereas HOXA5 expression was significantly lower. Our study showed that exogenous inhibition of miR-375 promoted HOXA5 expression; on the contrary, miR-375 mimics down-regulated HOXA5 expression level. Knockdown of miR-375 expression in BC cells reduces cell proliferation, migration, and invasion by inverse correlation expression of HOXA5. Our findings associated that miR-375 accelerated apoptosis evasion, proliferation, migration, and invasion by targeting HOXA5. In addition, nucleolin interferes in miR-375 biogenesis while silencing of nucleolin significantly reduced miR-375 expression and increased HOXA5 expression in BC. Thus, miR-375/HOXA5 axis may represent a potential therapeutic target for BC treatment.
Assuntos
Neoplasias da Mama , MicroRNAs , Humanos , Feminino , MicroRNAs/metabolismo , Neoplasias da Mama/metabolismo , Células HEK293 , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismoRESUMO
Hepatocellular carcinoma (HCC) remains the third leading malignancy worldwide, causing high mortality in adults and children. The neuropathology-associated gene AEG-1 functions as a scaffold protein to correctly assemble the RNA-induced silencing complex (RISC) and optimize or increase its activity. The overexpression of oncogenic miRNAs periodically degrades the target tumor suppressor genes. Oncogenic miR-221 plays a seminal role in the carcinogenesis of HCC. Hence, the exact molecular and biological functions of the oncogene clusters miR-221/AEG-1 axis have not yet been examined widely in HCC. Here, we explored the expression of both miR-221 and AEG-1 and their target/associate genes by qRT-PCR and western blot. In addition, the role of the miR-221/AEG-1 axis was studied in the HCC by flow cytometry analysis. The expression level of the AEG-1 did not change in the miR-221 mimic, and miR-221-transfected HCC cells, on the other hand, decreased the miR-221 expression in AEG-1 siRNA-transfected HCC cells. The miR-221/AEG-1 axis silencing induces apoptosis and G2/M phase arrest and inhibits cellular proliferation and angiogenesis by upregulating p57, p53, RB, and PTEN and downregulating LSF, LC3A, Bcl-2, OPN, MMP9, PI3K, and Akt in HCC cells.
Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , MicroRNAs , Carcinoma Hepatocelular/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/genética , Criança , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Hepáticas/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , RNA Interferente Pequeno , Complexo de Inativação Induzido por RNA/genética , Transdução de Sinais , Proteína Supressora de Tumor p53/metabolismoRESUMO
[This corrects the article DOI: 10.3389/fonc.2019.00847.].
RESUMO
Hepatocellular carcinoma (HCC) is the third leading malignancy worldwide, causing mortality in children and adults. AEG-1 is functioned as a scaffold protein for the proper assembly of RNA-induced silencing complex (RISC) to optimize or increase its activity. The increased activity of oncogenic miRNAs leads to the degradation of target tumor suppressor genes. miR-221 is an oncogenic miRNA, that plays a seminal role in carcinogenesis regulation of HCC. However, the molecular mechanism and biological functions of the miR-221/AEG-1 axis have not been investigated extensively in HCC. Here, the expression of miR-221/AEG-1 and their target/associate genes was analyzed by qRT-PCR and Western blot. The role of the miR-221/AEG-1 axis in HCC was evaluated by proliferation assay, migration assay, invasion assay, and flow cytometry analysis. The expression level of miR-221 decreased in AEG-1 siRNA transfected HCC cells. On the other hand, there were no significant expression changes of AEG-1 in miR-221 mimic and miR-221 inhibitor transfected HCC cells and inhibition of miR-221/AEG-1 axis decreased cell proliferation, invasion, migration, and angiogenesis and induced apoptosis, cell cycle arrest by upregulating p57, p53, PTEN, and RB and downregulating LSF, MMP9, OPN, Bcl-2, PI3K, AKT, and LC3A in HCC cells. Furthermore, these findings suggest that the miR-221/AEG-1 axis plays a seminal oncogenic role by modulating PTEN/PI3K/AKT signaling pathway in HCC. In conclusion, the miR-221/AEG-1 axis may serve as a potential target for therapeutics, diagnostics, and prognostics of HCC.
Assuntos
Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Progressão da Doença , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Proteínas de Membrana/metabolismo , MicroRNAs/metabolismo , Proteínas de Ligação a RNA/metabolismo , Transdução de Sinais , Apoptose/genética , Autofagia/genética , Carcinoma Hepatocelular/irrigação sanguínea , Ciclo Celular/genética , Pontos de Checagem do Ciclo Celular/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Regulação para Baixo/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Hepáticas/irrigação sanguínea , MicroRNAs/genética , Invasividade Neoplásica , Neovascularização Patológica/genética , PTEN Fosfo-Hidrolase/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismoRESUMO
Cervical Cancer (CC) is a highly aggressive tumor and is one of the leading causes of cancer-related deaths in women. miR-375 was shown to be significantly down-regulated in cervical cancer cells. However, the precise biological functions of miR-375 and the molecular mechanisms underlying its action in CC are largely unknown. miR-375 targets were predicted by bioinformatics target prediction tools and validated using luciferase reporter assay. Herein, we investigated the functional significance of miR-375 and its target gene in CC to identify potential new therapeutic targets. We found that miR-375 expression was significantly downregulated in CC, and astrocyte elevated gene-1 (AEG-1) was identified as a target of miR-375. Our results also showed that ectopic expression of miR-375 suppressed CC cell proliferation, migration, invasion and angiogenesis, and increased the 5-fluorouracil-induced apoptosis and cell cycle arrest in vitro. In contrast, inhibition of miR-375 expression significantly enhanced these functions. Furthermore, HPV - 16 E6/E7 and HPV - 18 E6/E7 significantly down-regulates miR-375 expression in CC. HPV 16/18-E6/E7/miR-375/AEG-1 axis plays an important role in the regulation of cell proliferation, migration, and invasion in CC. Therefore, targeting miR-375/AEG-1 mediated axis could serve as a potential therapeutic target for CC.