Investigating the Effects of Chenopodium album and Caralluma tuberculata on High Aggressive Acute Myeloid Leukemia

Abstract

Background: Acute myeloid leukemia (AML) t (6;9), which is also called High Aggressive AML is a subtype of AML. This form of AML makes up only 1% of all cases. High Aggressive AML has an early onset, aggressive disease progression, poor prognosis, low complete remission rate along with low survival rates in patients. Non-specific chemotherapy followed by Bone marrow transplantation is the only treatment currently available for High Aggressive AML; however, this subtype of AML has been seen to be resistant to chemotherapy. C. album and C. tuberculata are plant species found commonly in Asia and other regions of the world and have been used in traditional medicine for hundreds of years. Recently, research has shown that extracts of these plants show anticancer effects against solid tumor cancers, but more investigation needs to be done to determine their anticancer potential against liquid tumors. Aim: Our aim was to evaluate the anti-proliferative role of C. album and C. tuberculata in High Aggressive AML cell line FKH1 having t (6:9), DEK-NUP214 fusion oncogene and ETV6-ABL1 mutation. We also aimed to evaluate the anti-proliferative role of C. album and C. tuberculata on the U937 cell line, which is a commonly used AML cell line having no DEK-NUP214 or ABL mutation. Methodology: Extracts of C. album and C. tuberculata were separately assessed for potential antiproliferative effects in FKH1 and U937 cells using MTT assays. In FKH1, the activities of each extract were also compared with those of imatinib. DNA fragmentation assay and gene expression analysis of c Myc, Eya3, p21 and p53 was conducted to assess the mechanism by which the two extracts interfered with proliferation. Results: C. album and C. tuberculata both decreased the proliferation of FKH1 and U937 cells in a dose dependent manner. In FKH1 cells, the recorded IC-50 values of C. album and C. tuberculata were found to be approximately 150ug/ml and 7.5ug/ml respectively with high significance of growth inhibition at these concentrations (p<0.0001). Upon comparing the effects of imatinib and C. album in FKH1 cells, comparable antiproliferative activity was observed near IC-50 values of both. Likewise, similar results were recorded in FKH1 cells when comparing C. tuberculata with imatinib. However, when comparing the effective concentrations of C. album and C. tuberculata, it is evident that C. tuberculata shows much stronger inhibition of proliferation. Abstract xx DNA fragmentation assay performed in FKH1 cells showed no apoptosis caused by either of the extracts. Gene expression analysis showed that both extracts downregulated the expression of the c-Myc and Eya3 genes, with C. tuberculata showing a stronger downregulation effect (p<0.001 for both c-Myc and eya3). Gene expression of p53 and p21 was upregulated in FKH1 cells upon treatment with the plant extracts. C. tuberculata showed a higher gene upregulation effect in both p53 and p21. Conclusion: Through this study, we found that both C. album and C. tuberculata extracts interfered with the proliferative potential in U937 and FKH1 with C. tuberculata showing much more potent activity. In FKH1 cells, this interference was in a manner that was comparable to that induced by a standard inhibitor of growth in ABL positive cell lines i.e. imatinib. Furthermore, in terms of the underlying mechanisms of the observed anti-proliferative effects, our results show that C. album and C. tuberculata exert these through cell cycle arrest. In order to corroborate these results, translational studies, cell cycle analysis and more sensitive experiments such as Taq-man PCR need to be conducted. A detailed GCMS analysis of C. album and C. tuberculata plant extract and further studies with focus on the molecular aspects are needed.