Abstract 3833: Leonurine derivatives as a potential novel therapeutic approach to acute lymphoblastic leukemias (ALL)
Authors: Schramm Joseph W. , Ehudin Melanie , He Bing , Singh Chingakham , Bogush Daniel , Hengst Jeremy , Tukaramrao Diwakar Bastihalli , Sharma Arati , Desai Dhimant , Dovat Sinisa 
Published: April 2023

Background: Pre-B cell Acute lymphoblastic leukemia (B ALL) high risk (HR) subgroups continue to result in significant mortality and morbidity of pediatric oncology patients. T cell ALL is higher risk and therapy has made less improvement than B ALL with a higher rate of significant poor outcomes. Novel treatment strategies are required to overcome chemotherapy resistance and improve mortality/morbidity for HR B ALL. Leonurine is a bioactive alkaloid that is naturally occurring only in Herbra Leonuri which has been used in traditional herbal medicine. Traditionally, it has been used for menstrual disorders. Research has further described its ability to scavenge oxygen free radicals, anticoagulation properties, and other anti-inflammatory properties[1]. There are investigations in its role for myocardial infarction, stroke, chronic kidney disease, and other inflammatory disorders[2]. Our research data that suggests that leonurine and its derivatives have antileukemic effects.Methods/Results: We analyzed multiple derivatives of leonurine and selected a potent candidate based on cell viability assays use for further testing designated as investigational leonurine derivative (ILD). WST1 proliferation studies comparing ILD to vehicle were performed in cell lines Nalm6, 697, Molt4, CEM, and JM1 at multiple time points. The half maximal inhibitory concentration (IC50) values was variable depending on the treatment time and cell line although all values were consistently between 1.2-4.4 uM. Apoptosis activity was determined by flow cytometry Anexin/7AAD assays showed increased apoptosis in cell lines treated with ILD for Nalm6, Molt4, and 697 cell lines. Caspase 3/7 activity was increased in cells treated with ILD when compared to vehicle treatment. DNA damage assays were performed which revealed only an increased frequency in single strand breaks and not double strand breaks. Western blot was performed to determine levels of PI3K, p-AKT, BCL2/BCL-XL and caspases. The blots suggest that apoptosis may be a result of increased activation of PI3K/AKT signaling. We performed RNAseq on cells treated with ILD at the 24-hour time point and present gene ontology data for this analysis. Nalm6, 697, and Molt4 cell lines expressing GFP and Luciferase were injected into NRG mice as means for in vivo pharmacologic testing. NRG mice injected with these cell lines were treated with ILD five days a week for a total of 3 weeks. Nalm 6 leukemia cells showed minimal differences between treatment and control groups.Conclusion: In summary, leonurine derivatives have a promising impact on apoptosis and cell survival. Further investigation into mechanisms and pharmacokinetics/dynamics will be more revealing. Study of leonurine derivatives will result in further translational and therapeutic applications.

Citation Format: Joseph W. Schramm, Melanie Ehudin, Bing He, Chingakham Singh, Daniel Bogush, Jeremy Hengst, Diwakar Bastihalli Tukaramrao, Arati Sharma, Dhimant Desai, Sinisa Dovat. Leonurine derivatives as a potential novel therapeutic approach to acute lymphoblastic leukemias (ALL). [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 3833.