Therapeutic Effect of Thymoquinone on MAPK Signalling Pathway in K562 Chronic Myeloid Leukaemia Cells

Abstract

INTRODUCTION: Chronic Myeloid Leukaemia (CML) is a hematopoietic malignancy caused by the BCR-ABL1 fusion oncoprotein, originating from Philadelphia chromosome translocation that enhances leukemic cell survival and therapeutic resistance. Aberrant MAPK pathway activation promotes proliferation and inhibits apoptosis, contributing to CML progression and resistance to tyrosine kinase inhibitors like imatinib with prolonged use. Thymoquinone (TQ), a bioactive molecule, has attracted considerable interest Z for its anticancer characteristics that are worth investigating. MATERIALS AND METHODS: K562 CML cells were divided into an untreated group and a TQ-treated group and observed for 24 and 48 hours. Different TQ concentrations were administered to the TQ-treated group. Dose and time dependent effects on cell growth were assessed to evaluate cytotoxicity and determine the IC50 value in both groups. RNA was extracted from K562 CML cells based on the IC50 value and proceeded with RT-qPCR analysis on 7 genes involved, assigned as Raf1, B-Raf, ERK1, ERK2, K-Ras, H-Ras, and N-Ras genes, while the beta-actin gene was used as a housekeeping gene. Protein was extracted for the determination of protein and phosphorylation levels of Raf, MEK1/2, and ERK1/2, and assessed using the Jess Simple Western protocol. The Wilcoxon Signed-Rank test was performed using IBM SPSS, with p<0.05 considered statistically significant. Results: TQ treatment significantly reduced the expression of all genes analysed in K562 cells. It also decreased protein and phosphorylation levels of Raf, MEK1/2, and ERK1/2. Conclusion: These findings suggest that TQ effectively inhibits MAPK signalling in K562 CML cells, highlighting its potential as a future treatment for CML.