Dietary Turmeric Bisdemethoxycurcumin Suppresses Wilms’ Tumor 1 and CD34 Protein Expressions in KG-1a Leukemic Stem Cells

Abstract

Leukemic cells remaining in the body is the main problem for cancer patients, and these cells are called Leukemic Stem Cells (LSCs). Many studies have revealed that the overexpression of the Wilms’ tumor 1 (WT1) protein is related to leukemogenesis. Curcuminoids (curcumin, demethoxycurcumin, and bisdemethoxycurcumin) from Thai turmeric (Curcuma longa Linn.) are the focus of this study because they have been previously been reported to show potent antileukemic activity. This study aims to investigate the cytotoxic effect of in-house curcuminoids on the human leukemic stem cell line (KG-1a) when compared to other leukemic cell lines (KG-1 and K562). MTT assays were used to determine the cytotoxicity of curcuminoids at various concentrations. Curcumin exhibited the strongest cytotoxic activity on KG-1a cells with IC₅₀ values of 13.6 ± 1.9 µM. To determine the effect of curcuminoids on WT1 and CD34 protein expressions by Western blotting, KG-1a cells were treated with noncytotoxic concentrations (IC₂₀ value). Bisdemethoxycurcumin showed the strongest suppression of WT1 and CD34 protein expressions with 73.3 ± 1.4 and 82.9 ± 2.0%, respectively. In summary, curcuminoids, especially bisdemethoxycurcumin, could inhibit WT1 and CD34 protein expressions. Thus, bisdemethoxycurcumin is a compound that calls for further studies of its process in the inhibition of WT1 and CD34 expressions in LSCs for the leukemia treatment.

Author’s Contribution

S.A. devised the project and the main conceptual idea. S.T., S.C., and S.A. contributed to the design and implementation of the research. P.P. carried out the experiments and wrote the manuscript with input from all authors. All authors discussed the results and commented on the final manuscript.

Acknowledgment

We gratefully acknowledge Jordan Travis Cardwell for his critical reading of the manuscript for English usage.

Disclosure Statement

The authors declare that they have no conflict of interest.

Additional information

Funding

This work was supported by the National Research Council (NRC) and Chiang Mai University under Grant number 348438.