ABSTRACT
Acute myeloid leukemia (AML) has a poor survival rate for both pediatric and adult patients due to its frequent relapse. To elucidate the bioenergetic principle underlying AML relapse, we investigated the transcriptional regulation of mitochondrial-nuclear dual genomes responsible for metabolic plasticity in treatment-resistant blasts. Both the gain and loss of function results demonstrated that NFκB2, a noncanonical transcription factor (TF) of the NFκB (nuclear factor kappa-light-chain-enhancer of activated B cells) family, can control the expression of TFAM (mitochondrial transcription factor A), which is known to be essential for metabolic biogenesis. Furthermore, genetic tracking and promoter assays revealed that NFκB2 is in the mitochondria and can bind the specific "TTGGGGGGTG" region of the regulatory D-loop domain to activate the light-strand promoter (LSP) and heavy-strand promoter 1 (HSP1), promoters of the mitochondrial genome. Based on our discovery of NFκB2's novel function of regulating mitochondrial-nuclear dual genomes, we explored a novel triplet therapy including inhibitors of NFκB2, tyrosine kinase, and mitochondrial ATP synthase that effectively eliminated primary AML blasts with mutations of the FMS-related receptor tyrosine kinase 3 (FLT3) and displayed minimum toxicity to control cells ex vivo. As such, effective treatments for AML must include strong inhibitory actions on the dual genomes mediating metabolic plasticity to improve leukemia prognosis.
Subject(s)
Genome, Mitochondrial , Leukemia, Myeloid, Acute , Humans , Leukemia, Myeloid, Acute/genetics , Cell Line, Tumor , Promoter Regions, Genetic , Transcription Factors/genetics , Transcription Factors/metabolism , Cell Nucleus/metabolism , Cell Nucleus/genetics , DNA-Binding Proteins/genetics , DNA-Binding Proteins/metabolism , Mitochondria/metabolism , Mitochondria/genetics , Mitochondrial Proteins/genetics , Mitochondrial Proteins/metabolism , Gene Expression Regulation, LeukemicABSTRACT
Acute myeloid leukemia (AML) is a hematological malignancy that is characterized by an expansion of immature myeloid precursors. Despite therapeutic advances, the prognosis of AML patients remains poor and there is a need for the evaluation of promising therapeutic candidates to treat the disease. The objective of this study was to evaluate the efficacy of duocarmycin Stable A (DSA) in AML cells in vitro. We hypothesized that DSA would induce DNA damage in the form of DNA double-strand breaks (DSBs) and exert cytotoxic effects on AML cells within the picomolar range. Human AML cell lines Molm-14 and HL-60 were used to perform 3-(4,5-dimethylthiazolyl-2)-2,5-diphenyltetrazolium bromide (MTT), DNA DSBs, cell cycle, 5-ethynyl-2-deoxyuridine (EdU), colony formation unit (CFU), Annexin V, RNA sequencing and other assays described in this study. Our results showed that DSA induced DNA DSBs, induced cell cycle arrest at the G2M phase, reduced proliferation and increased apoptosis in AML cells. Additionally, RNA sequencing results showed that DSA regulates genes that are associated with cellular processes such as DNA repair, G2M checkpoint and apoptosis. These results suggest that DSA is efficacious in AML cells and is therefore a promising potential therapeutic candidate that can be further evaluated for the treatment of AML.
Subject(s)
Apoptosis , Cell Proliferation , Duocarmycins , Leukemia, Myeloid, Acute , Humans , Apoptosis/drug effects , Leukemia, Myeloid, Acute/drug therapy , Leukemia, Myeloid, Acute/pathology , Leukemia, Myeloid, Acute/metabolism , Cell Proliferation/drug effects , Duocarmycins/pharmacology , Cell Line, Tumor , DNA Breaks, Double-Stranded/drug effects , HL-60 Cells , Antineoplastic Agents/pharmacology , Cell Cycle Checkpoints/drug effects , DNA Damage/drug effectsABSTRACT
This case-control study evaluates whether adjuvant radiotherapy is associated with overall survival among patients with surgically resected stage III Merkel cell carcinoma.