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.