Indirubin in Vitro Apoptotic Effect on Chronic Lymphocytic Leukemia Cells Publisher



Jaafarinejad H^{1, 2} ; Yarmohammadi R^{3, 4} ; Piccin A^{5, 6, 7} ; Aghaei A⁸ ; Rostami T⁹ ; Faranoush M¹⁰ ; Hemati M¹ ; Nikroo ND¹¹ ; Sadighimoghaddam B¹ ; Kokhaei P^{1, 12, 13}
Source: Middle East Journal of Rehabilitation and Health Studies Published:2025

Abstract

Background: Chronic lymphocytic leukemia (CLL) primarily affects the elderly, with its etiology largely unknown. It is hypothesized that hematopoietic stem cells may acquire mutations over time, such as the BCL-2 mutation, leading to disruptions in the apoptotic process. Dangui Luhui Wan, a mixture of 11 herbs used in Chinese Medicine, has shown antitumor activities across various cancer cell types. Indirubin-3'-monoxime (I3M), derived from Dangui Luhui Wan, functions as a selective inhibitor of cyclin-dependent kinases (CDKs) and can induce apoptosis in cells. Objectives: The objective of this study was to evaluate the effectiveness of I3M against CLL cells in vitro. Methods: Peripheral blood mononuclear cells (PBMCs) from 14 patients were treated with I3M at concentrations ranging from 0.1 μM to 80 μM over periods of 24, 48, and 72 hours. The optimal dose was determined using Annexin V and MTT assays. The expression of apoptotic genes Bcl-2/Bax and CDK1/2 was assessed using real-time PCR. Results: The results indicated that a 20 µM concentration of I3M exhibited the highest cytotoxicity after 48 hours compared to controls (P = 0.005). Post-treatment, a decrease in Bcl-2 gene expression was observed, while changes in the Bax gene were not significant. However, an increase in the Bax/Bcl-2 gene ratio was noted, suggesting involvement of the mitochondrial pathway in I3M's apoptotic mechanism. Notably, I3M inhibited the expression of the CDK2 gene but did not affect CDK1 gene expression. Conclusions: I3M appears to exert antitumor effects by inducing apoptosis and inhibiting the CDK2 gene. Further research is required to elucidate the precise mechanism of action of I3M in CLL and potentially other tumor cell lines. © 2024, Jaafarinejad et al.