RESUMO
The rs619586 polymorphism has been shown to alter the expression of MALAT1, which act as a competing endogenous RNA (ceRNA) against miR-145. And miR-145 was found to target COL5A1, the interaction between which was shown to be involved in the pathogenesis of invasive meningioma. In this study, we aimed to explore the effect of rs619586 polymorphism and its underlying molecular mechanism in invasive meningioma. Real-time PCR and Western Blot analysis were used to study the differentiated expression of miR-145, MALAT1 (metastasis-associated lung adenocarcinoma transcript 1) and COL5A1 (collagen alpha-1(V) chain) in tumour/serum samples genotyped as rs619586 AA, AG and GG. Computational analysis and luciferase reporter assay were also conducted to identify the regulatory relationship between miR-145 and MALAT1/COL5A1. Meanwhile, expression of miR-145 and COL5A1 in different cell treatment groups was measured to validate the results obtained from earlier experiments. As shown by the results and in tumour/serum samples genotyped as AA, AG and GG, the expression of both MALAT1 and COL5A1 was down-regulated in a stepwise fashion, while the expression of miR-145 was increased, suggesting a potential negative relationship between MALAT1/COL5A1 and miR-145. Meanwhile, miR-145 was shown to bind to MALAT1, while COL5A1 was identified as a virtual target gene of miR-145. As a consequence, a MALAT1/miR-145/COL5A1 molecular pathway was established based on the above results. In particular, with the presence of rs619586 A>G polymorphism, the expression of MALAT1 and COL5A1 was both reduced, leading to reduced invasiveness of meningioma.
Assuntos
Colágeno Tipo V/genética , Neoplasias Meníngeas/genética , Meningioma/genética , Invasividade Neoplásica/genética , Polimorfismo de Nucleotídeo Único/genética , RNA Longo não Codificante/genética , Alelos , Linhagem Celular Tumoral , Proliferação de Células/genética , Células Cultivadas , Regulação para Baixo/genética , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Genótipo , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
OBJECTIVE: The Notch signaling pathway has been well recognized as important adjuster in glioma tumorigenesis and could regulate the glioma cell proliferation through downstream factors such as epidermal growth factor receptor (EGFR). Our current study was aim to investigate the clinical association between Notch-1 gene and EGFR gene as well as cell survival rate in human glioblastoma multiforme (GBM) samples. PATIENTS AND METHODS: Samples from 90 patients with GBMs and 20 normal brain tissues were analyzed in our study. Western blot and immunohistochemistry was used to detect Notch and EGFR protein expression. RT-PCR was used to detect Notch and EGFR mRNA expression. Apoptosis was detected with flow cytometry. RESULTS: Results demonstrated that the Notch and EGFR gene mRNA and protein levels were dramatically higher in GBM tissues compared to normal brain. Further analysis found these increased mRNA levels were only associated with patient survival period, but not related to patient age, gender and tumor size. A positive correlation was observed between Notch and EGFR protein expression. The positive correlations were also exhibited between Notch-1, EGFR gene expression and apoptosis percentage. CONCLUSION: Our study verified both Notch-1 and EGFR involved in GBM tumorigenesis and may provide important information for GBM clinical treatment and prognosis.
