Definition of a small core transcriptional circuit regulated by AML1-ETO.

Transcription factors regulate gene networks controlling normal hematopoiesis and are frequently deregulated in acute myeloid leukemia (AML). Critical to our understanding of the mechanism of cellular transformation by oncogenic transcription factors is the ability to define their direct gene targets. However, gene network cascades can change within minutes to hours, making it difficult to distinguish direct from secondary or compensatory transcriptional changes by traditional methodologies. To overcome this limitation, we devised cell models in which the AML1-ETO protein could be quickly degraded upon addition of a small molecule. The rapid kinetics of AML1-ETO removal, when combined with analysis of transcriptional output by nascent transcript analysis and genome-wide AML1-ETO binding by CUT&RUN, enabled the identification of direct gene targets that constitute a core AML1-ETO regulatory network. Moreover, derepression of this gene network was associated with RUNX1 DNA binding and triggered a transcription cascade ultimately resulting in myeloid differentiation.

PLCG1 is required for AML1-ETO leukemia stem cell self-renewal.

In an effort to identify novel drugs targeting fusion-oncogene-induced acute myeloid leukemia (AML), we performed high-resolution proteomic analysis. In AML1-ETO (AE)-driven AML, we uncovered a deregulation of phospholipase C (PLC) signaling. We identified PLCgamma 1 (PLCG1) as a specific target of the AE fusion protein that is induced after AE binding to intergenic regulatory DNA elements. Genetic inactivation of PLCG1 in murine and human AML inhibited AML1-ETO dependent self-renewal programs, leukemic proliferation, and leukemia maintenance in vivo. In contrast, PLCG1 was dispensable for normal hematopoietic stem and progenitor cell function. These findings are extended to and confirmed by pharmacologic perturbation of Ca++-signaling in AML1-ETO AML cells, indicating that the PLCG1 pathway poses an important therapeutic target for AML1-ETO+ leukemic stem cells.

Different roles of E proteins in t(8;21) leukemia: E2-2 compromises the function of AETFC and negatively regulates leukemogenesis.

The AML1-ETO fusion protein, generated by the t(8;21) chromosomal translocation, is causally involved in nearly 20% of acute myeloid leukemia (AML) cases. In leukemic cells, AML1-ETO resides in and functions through a stable protein complex, AML1-ETO-containing transcription factor complex (AETFC), that contains multiple transcription (co)factors. Among these AETFC components, HEB and E2A, two members of the ubiquitously expressed E proteins, directly interact with AML1-ETO, confer new DNA-binding capacity to AETFC, and are essential for leukemogenesis. However, the third E protein, E2-2, is specifically silenced in AML1-ETO-expressing leukemic cells, suggesting E2-2 as a negative factor of leukemogenesis. Indeed, ectopic expression of E2-2 selectively inhibits the growth of AML1-ETO-expressing leukemic cells, and this inhibition requires the bHLH DNA-binding domain. RNA-seq and ChIP-seq analyses reveal that, despite some overlap, the three E proteins differentially regulate many target genes. In particular, studies show that E2-2 both redistributes AETFC to, and activates, some genes associated with dendritic cell differentiation and represses MYC target genes. In AML patients, the expression of E2-2 is relatively lower in the t(8;21) subtype, and an E2-2 target gene, THPO, is identified as a potential predictor of relapse. In a mouse model of human t(8;21) leukemia, E2-2 suppression accelerates leukemogenesis. Taken together, these results reveal that, in contrast to HEB and E2A, which facilitate AML1-ETO-mediated leukemogenesis, E2-2 compromises the function of AETFC and negatively regulates leukemogenesis. The three E proteins thus define a heterogeneity of AETFC, which improves our understanding of the precise mechanism of leukemogenesis and assists development of diagnostic/therapeutic strategies.

Leukemia associated RUNX1T1 gene reduced proliferation and invasiveness of glioblastoma cells.

RUNX1T1 has been found to be mutated in different cancers such as prostate, lung, colon, and breast cancer. A recent computational study involving the TCGA database of glioma patients found RUNX1T1 as one of the downregulated driver genes associated with poor overall survival of glioma patients. Hypoxia-inducible factor 1α (HIF1α) is upregulated in glioma and has been associated with the severity and drug resistance of glioma. Previously, we have shown that RUNX1T3 degrades HIF1α affecting the proliferation of leukemia cells. We hypothesize that RUNX1T1 might be associated with the growth and development of glioma through the regulation of HIF1α. We have evaluated the expression level of RUNX1T1 at different stages of glioma and the effect of RUNX1T1 on the proliferation and invasiveness of glioblastoma cells in vitro. We further looked at the effect of RUNX1T1 on the expression and stability of HIF1α in vitro. Expression of RUNX1T1 was significantly downregulated, both at RNA and protein levels in glioma samples as studied by quantitative real-time polymerase chain reaction and immunohistochemistry. While expression of HIF1α was higher in glioma tissues compared with its level in the normal brain. In vitro studies demonstrated that RUNX1T1 interacted with HIF1α and recruited HIF1α modification factor such as PHD2 and GSK3ß causing hydroxylation of HIF1α following ubiquitination by FBW7. RUNX1T1 led to the degradation of HIF1α and decreased proliferation/invasiveness of glioblastoma cell lines. Further, RUNX1T1 increased the effectiveness of temozolomide (TMZ), a conventional glioma drug toward glioblastoma cell lines. This study indicates that downregulation of RUNX1T1 might play an important role in the severity and development of glioma.

HDN-1 induces cell differentiation toward apoptosis in promyelocytic leukemia cells depending on its selective effect on client proteins of Hsp90.

Heat Shock Protein 90 (Hsp90) is frequently upregulated in many cancers, and its inhibition simultaneously blocks multiple signaling pathways, resulting in cell differentiation or apoptosis. However, the complexity of Hsp90 in differentiation and its relation with apoptosis have remained unsettled. In this study, we demonstrated that HDN-1, a C-terminal inhibitor of Hsp90, induced the differentiation of HL-60 cells toward apoptosis. HDN-1 induced the differentiation of cells containing mutant AML1-ETO into mature granulocytes, which was related to its selective effect on client proteins of Hsp90. HDN-1 destabilized AML1-ETO and preserved C/EBPß at the same time, thereby induced a total increase in C/EBPß levels because of AML1-ETO negative regulation to C/EBPß expression. Neither HDN-1 nor 17-AAG (an N-terminal inhibitor of Hsp90) led to the differentiation of NB4 cells because mutant PML-RARα was not affected as a client protein of Hsp90; thus, no additional expression of C/EBPß was induced. 17-AAG did not affect the differentiation of HL-60 cells due to decreased AML1-ETO and C/EBPß levels. These results indicate that HDN-1 drives cell differentiation toward apoptosis depending on its selective influence on client proteins of Hsp90, establishing the relationship between differentiation and apoptosis and uncovering the mechanism of HDN-1 in promyelocytic leukemia cell differentiation. Moreover, HDN-1 is very promising for the development of anticancer agents with the induction of differentiation.

RUNX1T1, a potential prognostic marker in breast cancer, is co-ordinately expressed with ERα, and regulated by estrogen receptor signalling in breast cancer cells.

BACKGROUND: RUNX1T1 is extensively studied in the context of AML1-RUNX1T1 fusion protein in acute myeloid leukemia. Little is known about the function of RUNX1T1 itself, although data on its function and regulation have begun to emerge from clinical, and in vitro studies. It is a putative tumor suppressor, whose expression is altered in a variety of solid tumors. Recently, reduced expression of RUNX1T1 in triple-negative breast tumors, and its influence on prognosis was reported. METHODS AND RESULTS: The Kaplan-Meier Plotter online tool was used to study the relationship between RUNX1T1 expression and survival of breast cancer patients. High RUNX1T1 expression was associated with longer overall survival (OS), relapse-free survival (RFS) and distant metastasis free survival (DMFS). RUNX1T1 expression positively and negatively influenced OS of patients with ERα-positive and ERα-negative breast tumors, respectively. It was also associated with prolonged RFS, and DMFS in tamoxifen-treated patients. Expression of RUNX1T1 and ERα mRNA was analyzed in 40 breast tumor samples, and breast cancer cell lines using RT-PCR. TCGA-BRCA data was mined to study the relationship between RUNX1T1 and ERα mRNA expression. ERα-positive breast tumors showed significantly higher RUNX1T1 mRNA expression compared to ERα-negative tumors. RUNX1T1 mRNA expression was analyzed by qRT-PCR in MCF-7 or T47D cells, which were treated with 17ß-estradiol, or the ERα agonist PPT, alone or in combination with 4-hydroxytamoxifen. Effect of ERα knockdown was also investigated. Results indicate that estrogen downmodulated RUNX1T1 mRNA expression via ERα. CONCLUSION: Higher expression of RUNX1T1 in breast tumors is associated with favourable prognosis. RUNX1T1 and ERα show co-ordinated expression in breast tumors, and breast cancer cell lines. Estrogen-ERα signalling downmodulates the expression of RUNX1T1 mRNA in ERα-positive breast cancer cells. In-depth investigations on the interaction between RUNX1T1 and ERα are warranted to unravel the role and relevance of RUNX1T1 in breast cancer.

Epigenetic silencing of miR564 contributes to the leukemogenesis of t(8;21) acute myeloid leukemia.

The AML1-ETO oncoprotein, which results from t(8;21) translocation, is considered an initial event of t(8;21) acute myeloid leukemia (AML). However, the precise mechanisms of the oncogenic activity of AML1-ETO is yet to be fully determined. The present study demonstrates that AML1-ETO triggers the heterochromatic silencing of microRNA-564 (miR564) by binding at the AML1 binding site along the miR564 promoter region and recruiting chromatin-remodeling enzymes. Suppression of miR564 enhances the oncogenic activity of the AML1-ETO oncoprotein by directly inhibiting the expression of CCND1 and the DNMT3A genes. Ectopic expression of miR564 can induce retardation of G1/S transition, reperform differentiation, promote apoptosis, as well as inhibit the proliferation and colony formation of AML1-ETO+ leukemia cells in vitro. Enhanced miR564 levels can significantly inhibit the tumor proliferation of t(8;21)AML in vivo. We first identify an unexpected and important epigenetic circuitry of AML1-ETO/miR564/CCND1/DNMT3A that contributes to the leukemogenesis in vitro/vivo of AML1-ETO+ leukemia, indicating that miR564 enhancement could provide a potential therapeutic method for AML1-ETO+ leukemia.

Cell-intrinsic depletion of Aml1-ETO-expressing pre-leukemic hematopoietic stem cells by K-Ras activating mutation.

Somatic mutations in acute myeloid leukemia are acquired sequentially and hierarchically. First, pre-leukemic mutations, such as t(8;21) that encodes AML1-ETO, are acquired within the hematopoietic stem cell (HSC) compartment, while signaling pathway mutations, including KRAS activating mutations, are late events acquired during transformation of leukemic progenitor cells and are rarely detectable in HSC. This raises the possibility that signaling pathway mutations are detrimental to clonal expansion of pre-leukemic HSC. To address this hypothesis, we used conditional genetics to introduce Aml1-ETO and K-RasG12D into murine HSC, either individually or in combination. In the absence of activated Ras, Aml1-ETO-expressing HSC conferred a competitive advantage. However, activated K-Ras had a marked detrimental effect on Aml1-ETO-expressing HSC, leading to loss of both phenotypic and functional HSC. Cell cycle analysis revealed a loss of quiescence in HSC co-expressing Aml1-ETO and K-RasG12D, accompanied by an enrichment in E2F and Myc target gene expression and depletion of HSC self-renewal-associated gene expression. These findings provide a mechanistic basis for the observed absence of KRAS signaling mutations in the pre-malignant HSC compartment.

Elucidation of Novel Therapeutic Targets for Acute Myeloid Leukemias with RUNX1-RUNX1T1 Fusion.

The RUNX1-RUNX1T1 fusion is a frequent chromosomal alteration in acute myeloid leukemias (AMLs). Although RUNX1-RUNX1T1 fusion protein has pivotal roles in the development of AMLs with the fusion, RUNX1-RUNX1T1, fusion protein is difficult to target, as it lacks kinase activities. Here, we used bioinformatic tools to elucidate targetable signaling pathways in AMLs with RUNX1-RUNX1T1 fusion. After analysis of 93 AML cases from The Cancer Genome Atlas (TCGA) database, we found expression of 293 genes that correlated to the expression of the RUNX1-RUNX1T1 fusion gene. Based on these 293 genes, the cyclooxygenase (COX), vascular endothelial growth factor receptor (VEGFR), platelet-derived growth factor receptor (PDGFR), and fibroblast growth factor receptor (FGFR) pathways were predicted to be specifically activated in AMLs with RUNX1-RUNX1T1 fusion. Moreover, the in vitro proliferation of AML cells with RUNX1-RUNX1T1 fusion decreased significantly more than that of AML cells without the fusion, when the pathways were inhibited pharmacologically. The results indicate that novel targetable signaling pathways could be identified by the analysis of the gene expression features of AMLs with non-targetable genetic alterations. The elucidation of specific molecular targets for AMLs that have a specific genetic alteration would promote personalized treatment of AMLs and improve clinical outcomes.

AML1/ETO trans-activates c-KIT expression through the long range interaction between promoter and intronic enhancer.

The AML1/ETO onco-fusion protein is crucial for the genesis of t(8;21) acute myeloid leukemia (AML) and is well documented as a transcriptional repressor through dominant-negative effect. However, little is known about the transactivation mechanism of AML1/ETO. Through large cohort of patient's expression level data analysis and a series of experimental validation, we report here that AML1/ETO transactivates c-KIT expression through directly binding to and mediating the long-range interaction between the promoter and intronic enhancer regions of c-KIT. Gene expression analyses verify that c-KIT expression is significantly high in t(8;21) AML. Further ChIP-seq analysis and motif scanning identify two regulatory regions located in the promoter and intronic enhancer region of c-KIT, respectively. Both regions are enriched by co-factors of AML1/ETO, such as AML1, CEBPe, c-Jun, and c-Fos. Further luciferase reporter assays show that AML1/ETO trans-activates c-KIT promoter activity through directly recognizing the AML1 motif and the co-existence of co-factors. The induction of c-KIT promoter activity is reinforced with the existence of intronic enhancer region. Furthermore, ChIP-3C-qPCR assays verify that AML1/ETO mediates the formation of DNA-looping between the c-KIT promoter and intronic enhancer region through the long-range interaction. Collectively, our data uncover a novel transcriptional activity mechanism of AML1/ETO and enrich our knowledge of the onco-fusion protein mediated transcription regulation.

RUNX-mediated growth arrest and senescence are attenuated by diverse mechanisms in cells expressing RUNX1 fusion oncoproteins.

RUNX gene over-expression inhibits growth of primary cells but transforms cells with tumor suppressor defects, consistent with reported associations with tumor progression. In contrast, chromosomal translocations involving RUNX1 are detectable in utero, suggesting an initiating role in leukemias. How do cells expressing RUNX1 fusion oncoproteins evade RUNX-mediated growth suppression? Previous studies showed that the TEL-RUNX1 fusion from t(12;21) B-ALLs is unable to induce senescence-like growth arrest (SLGA) in primary fibroblasts while potent activity is displayed by the RUNX1-ETO fusion found in t(8;21) AMLs. We now show that SLGA potential is suppressed in TEL-RUNX1 but reactivated by deletion of the TEL HLH domain or mutation of a key residue (K99R). Attenuation of SLGA activity is also a feature of RUNX1-ETO9a, a minor product of t(8;21) translocations with increased leukemogenicity. Finally, while RUNX1-ETO induces SLGA it also drives a potent senescence-associated secretory phenotype (SASP), and promotes the immortalization of rare cells that escape SLGA. Moreover, the RUNX1-ETO SASP is not strictly linked to growth arrest as it is largely suppressed by RUNX1 and partially activated by RUNX1-ETO9a. These findings underline the heterogeneous nature of premature senescence and the multiple mechanisms by which this failsafe process is subverted in cells expressing RUNX1 oncoproteins.

Polyphyllin I Inhibits Proliferation and Induces Apoptosis by Downregulating AML1-ETO and Suppressing C-KIT/Akt Signaling in t(8;21) Acute Myeloid Leukemia.

Polyphyllin I (PPI), a bioactive constituent extracted from traditional medicinal herbs, is cytotoxic to several cancer types. However, whether PPI can be used to treat t(8;21) acute myeloid leukemia (AML) cells requires further investigation. Here, we determined the inhibitory effects of PPI on t(8;21) AML cells by Cell Counting Kit-8 (CCK-8) and the trypan blue dye exclusion assay. DAPI staining and Wright-Giemsa staining were performed to check for apoptosis. Detection of apoptotic protein and AML1-ETO signaling protein expression were conducted by Western blot analysis. Our results suggested that PPI decreased growth and induced apoptosis in a dosage-dependent manner in the t(8;21) AML cell line Kasumi-1. PPI significantly downregulated AML1-ETO expression in a dosage- and time-dependent manner. PPI also upregulated P21 and downregulated survivin expression by reducing AML1-ETO. Mechanistically, PPI significantly reduced the expression of C-KIT, another therapeutic target for AML with t(8;21), followed by inhibition of Akt signaling. These results suggest that PPI can suppress growth and induce apoptosis of t(8;21) AML by suppressing the AML1-ETO and C-KIT/Akt signaling pathways. Therefore, PPI may be an anticancer therapeutic to treat t(8;21) AML.

Characterization of RUNX1T1, an Adipogenesis Regulator in Ovine Preadipocyte Differentiation.

Runt-related transcription factor 1 translocation partner 1 (RUNX1T1), a potential novel regulator of adipogenesis, exists in two splice variants: a long (RUNX1T1-L) and a short (RUNX1T1-S) isoform. However, there is no data showing the existence of RUNX1T1 in ovine subcutaneous fat at different stages of developmental and its role on ovine adipogenesis. Therefore, the objectives of this study were to evaluate the presence of RUNX1T1 in subcutaneous fat of five-day-old to 24-month-old sheep and to investigate the role of RUNX1T1 in ovine adipogenesis. In this study, we detected a 1829 bp cDNA fragment of RUNX1T1 which contains a 1815 bp coding sequence that encodes 602-amino acid and 14 bp of 5' untranslated region, respectively. The amino acid sequence of RUNX1T1 has 31.18⁻94.21% homology with other species' protein sequences. During fat development, the RUNX1T1 protein expression was higher in subcutaneous fat of 24-month-old Hu sheep. In addition, the expression of RUNX1T1-L mRNA decreased first, then subsequently increased during ovine preadipocyte differentiation. Knockdown of RUNX1T1-L in ovine preadipocytes promoted preadipocyte differentiation and lipid accumulation. Taken together, our data suggests that RUNX1T1 is an important functional molecule in adipogenesis. Moreover, it showed for the first time that RUNX1T1-L was negatively correlated with the ovine preadipocyte differentiation.

CNS erythroblastic sarcoma: a potential emerging pediatric tumor type characterized by NFIA::RUNX1T1/3 fusions.

Erythroblastic sarcoma (ES) (previously called chloroma or granulocytic sarcoma) are rare hematological neoplams characterized by the proliferation of myeloid blasts at extramedullary sites, and primarily involve the skin and soft tissue of middle-aged adults. ES may be concomitant with or secondary to myeloid neoplasms (mostly acute myeloid leukemia (AML)) or in isolated cases (de novo) without infiltration of the bone marrow by blasts. ES share cytogenetic and molecular abnormalities with AML, including RUNX1T1 fusions. Some of these alterations seem to be correlated with particular sites of involvement. Herein, we report an isolated erythroblastic sarcoma with NFIA::RUNX1T1 located in the central nervous system (CNS) of a 3-year-old boy. Recently, two pediatric cases of CNS MS with complete molecular characterization have been documented. Like the current case, they concerned infants (2 and 3 years-old) presenting a brain tumor (pineal involvement) with leptomeningeal dissemination. Both cases also harbored a NFIA::RUNX1T3 fusion. ES constitutes a diagnostic challenge for neuropathologists because it does not express differentiation markers such as CD45, and may express CD99 which could be confused with CNS Ewing sarcoma. CD43 is the earliest pan-hematopoietic marker and CD45 is not expressed by erythroid lineage cells. E-cadherin (also a marker of erythroid precursors) and CD117 (expressed on the surface of erythroid lineage cells) constitute other immunhistochemical hallmarks of ES. The prognosis of patients with ES is similar to that of other patients with AML but de novo forms seem to have a poorer prognosis, like the current case. To conclude, pediatric ES with NFIA::RUNX1T1/3 fusions seem to have a tropism for the CNS and thus constitute a potential pitfall for neuropathologists. Due to the absence of circulating blasts and a DNA-methylation signature, the diagnosis must currently be made by highlighting the translocation and expression of erythroid markers.

Neratinib impairs function of m6A recognition on AML1-ETO pre-mRNA and induces differentiation of t (8;21) AML cells by targeting HNRNPA3.

Acute myeloid leukemia (AML) is frequently linked to genetic abnormalities, with the t (8; 21) translocation, resulting in the production of a fusion oncoprotein AML1-ETO (AE), being a prevalent occurrence. This protein plays a pivotal role in t (8; 21) AML's onset, advancement, and recurrence, making it a therapeutic target. However, the development of drug molecules targeting AML1-ETO are markedly insufficient, especially used in clinical treatment. In this study, it was uncovered that Neratinib could significantly downregulate AML1-ETO protein level, subsequently promoting differentiation of t (8; 21) AML cells. Based on "differentiated active" probes, Neratinib was identified as a functional inhibitor against HNRNPA3 through covalent binding. The further studies demonstrated that HNRNPA3 function as a putative m6A reader responsible for recognizing and regulating the alternative splicing of AML-ETO pre-mRNA. These findings not only contribute to a novel insight to the mechanism governing post-transcriptional modification of AML1-ETO transcript, but also suggest that Neratinib would be promising therapeutic potential for t (8; 21) AML treatment.

Protein-Nanocaged Selenium Induces t(8;21) Leukemia Cell Differentiation via Epigenetic Regulation.

The success of arsenic in degrading PML-RARα oncoprotein illustrates the great anti-leukemia value of inorganics. Inspired by this, the therapeutic effect of inorganic selenium on t(8; 21) leukemia is studied, which has shown promising anti-cancer effects on solid tumors. A leukemia-targeting selenium nanomedicine is rationally built with bioengineered protein nanocage and is demonstrated to be an effective epigenetic drug for inducing the differentiation of t(8;21) leukemia. The selenium drug significantly induces the differentiation of t(8;21) leukemia cells into more mature myeloid cells. Mechanistic analysis shows that the selenium is metabolized into bioactive forms in cells, which drives the degradation of the AML1-ETO oncoprotein by inhibiting histone deacetylases activity, resulting in the regulation of AML1-ETO target genes. The regulation results in a significant increase in the expression levels of myeloid differentiation transcription factors PU.1 and C/EBPα, and a significant decrease in the expression level of C-KIT protein, a member of the type III receptor tyrosine kinase family. This study demonstrates that this protein-nanocaged selenium is a potential therapeutic drug against t(8;21) leukemia through epigenetic regulation.

RUNX1T1 function in cell fate.

RUNX1T1 (Runt-related transcription factor 1, translocated to 1), a myeloid translocation gene (MTG) family member, is usually investigated as part of the fusion protein RUNX1-RUNX1T1 for its role in acute myeloid leukemia. In the main, by recruiting histone deacetylases, RUNX1T1 negatively influences transcription, enabling it to regulate the proliferation and differentiation of hematopoietic progenitors. Moreover, the formation of blood vessels, neuronal differentiation, microglial activation following injury, and intestinal development all relate closely to the expression of RUNX1T1. Furthermore, through alternative splicing of RUNX1T1, short and long isoforms have been noted to mediate adipogenesis by balancing the differentiation and proliferation of adipocytes. In addition, RUNX1T1 plays wide-ranging and diverse roles in carcinoma as a biomarker, suppressor, or positive regulator of carcinogenesis, closely correlated to specific organs and dominant signaling pathways. The aim of this work was to investigate the structure of RUNX1T1, which contains four conserved nervy homolog domains, and to demonstrate crosstalk with the Notch signaling pathway. Moreover, we endeavored to illustrate the effects of RUNX1T1 on cell fate from multiple aspects, including its influence on hematopoiesis, neuronal differentiation, microglial activation, intestinal development, adipogenesis, angiogenesis, and carcinogenesis.

Comprehensive Mutation Profile in Acute Myeloid Leukemia Patients with RUNX1-RUNX1T1 or CBFB-MYH11 Fusions

Objective: This study was undertaken with the aim of better understanding the genomic landscape of core-binding factor (CBF) acute myeloid leukemia (AML). Materials and Methods: We retrospectively analyzed 112 genes that were detected using next-generation sequencing in 134 patients with de novo CBF-AML. FLT3-ITD, NPM1, and CEBPA mutations were detected by DNA-PCR and Sanger sequencing. Results: In the whole cohort, the most commonly mutated genes were c-KIT (33.6%) and NRAS (33.6%), followed by FLT3 (18.7%), KRAS (13.4%), RELN (8.2%), and NOTCH1 (8.2%). The frequencies of mutated genes associated with epigenetic modification, such as IDH1, IDH2, DNMT3A, and TET2, were low, being present in 1.5%, 0.7%, 2.2%, and 7.5% of the total number of patients, respectively. Inv(16)/t(16;16) AML patients exhibited more mutations of NRAS and KRAS (p=0.001 and 0.0001, respectively) than t(8;21) AML patients. Functionally mutated genes involved in signaling pathways were observed more frequently in the inv(16)/t(16;16) AML group (p=0.016), while the mutations involved in cohesin were found more frequently in the t(8;21) AML group (p=0.011). Significantly higher white blood cell counts were found in inv(16)/t(16;16) AML patients with c-KIT (c-KITmut) or NRAS (NRASmut) mutations compared to the corresponding t(8;21) AML/c-KITmut and t(8;21) AML/NRASmut groups (p=0.001 and 0.009, respectively). Conclusion: The mutation profiles of t(8;21) AML patients showed evident differences from those of patients with inv(16)/t(16;16) AML. We have provided a comprehensive overview of the mutational landscape of CBF-AML.