Noscapine Induces Apoptosis and Inhibits Invasion in Caco-2 Colon Cancer Cells via Overexpression of miR-218 As Well as Down-Regulation of lncRNA CCAT2, MYC, and GLI1

Abstract

Background: There are growing evidences related with critical role of non-coding RNAs (lncRNAs), oncogenes, and microRNAs (miRNAs) in pathogenesis and metastatic capacity of Colorectal Cancer (CRC). This study aimed to elucidate the pro-apoptotic and anti-metastatic effect of Noscapine as alkaloid compound in addition its effect on CCAT2, miR-218-5p, MYC, and GLI in Caco-2 CRC cells. 

Methods: Caco-2 cells were exposed to increasing concentrations of Noscapine (10–100 μM). The cytotoxicity, DNA damage, apoptosis recruitment, and cell cycle analysis were examined using MTT assay, comet assay, and fluorometric analysis. IC50 measured by GraphPad Prism software was used for anti-cancer analysis. To assess cell invasion, a scratch assay was performed. The quantitative changes in the expression of CCAT2, miR-218-5p, and MYC, GLI1 were evaluated by qRT-PCR. 

Results: The MTT assay showed the dose and time dependent attenuation of Caco-2 cells survival rate compared to the control. Comet assay demonstrated significant DNA damage in treated cells. The flow cytometry indicated cell cycle arrest at the G0/G1 phase and late apoptotic and necrotic cell increment. The scratch assay confirmed impaired migration, with markedly reduced wound closure in IC50 treated group. The qRT-PCR showed that in contrast to remarkable up-regulation of miRNA 218 (*p<0.05), the level of CCAT2 (*p<0.05), MYC (**p<0.01) and GLI1 (**p<0.01) was significantly diminished in Noscapine treated cells.  

Conclusion: Noscapine exhibited anti-proliferative and anti-migratory effects in Caco-2 CRC cells, which are associated with altered expression of CCAT2, miR-218, MYC, and GLI1.