The effect of RAN inhibition on human colorectal cancer cells (CRC)

Abstract

Colorectal cancer (CRC) is the third most widespread and fourth most fatal malignancy disease. The CRC from a primary site can spread to other tissues, forming secondary tumours. CRC can metastasise to the liver through the effect of K-Ras and Pten mutation (Mt.) (Abbas et al. 2020). This study aimed to assess the hypothesis that the Ran inhibitor mebendazole MBZ reduces cell invasion and metastasis of CRC. I have investigated MBZ effect on the CRC isogenic human cell lines with specific mutations (HCT-116 K-Ras, DLD-1 K-Ras and Pten deletion and wild type HCT-116 and DKO-3. I used qRT-PCR and western blotting to identify expression levels of various genes and signalling molecules after treatment with 0.5 mM MBZ. In addition, several assays were performed to investigate MBZ effect on biological properties of the cells such as proliferation, migration, invasion, and colony formation. MBZ downregulated Ran and induced apoptosis through inhibition of Bcl-2 expression as well as inducing caspase -3, -7, -9 and PARP cleavage. Moreover, MBZ showed an effect on immune response by down regulating C5a, IL-1ß and IL-1α analysed at mRNA level. When treated with MBZ, the migration, invasion and colony formation abilities of HCT-116 K-Ras Mt., DLD-1 K-Ras Mt. and HCT-116 Pten-/- were significantly reduced compared to a control treated cell line. This was also the case with wild type cell lines such as HCT-116 and DKO-3. Furthermore, signalling molecules such as p- Erk 1/2 and p- Akt were upregulated after MBZ treatment and exert inhibition on Akt 1/2/3 and VEGFR1/2 mRNA levels. In conclusion; MBZ which is a Ran inhibitor, has significantly reduced proliferation, colony formation, and migration in colorectal cell lines with K-Ras and Pten gene deletion compared to wild type cells in a dose-dependent manner. This work paves the way to clinical validation of MBZ as a combination therapy for reducing the invasion of CRC cells.