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KF1601, a dual inhibitor of BCR::ABL1 and FLT3, overcomes drug resistance in FLT3+ blast phase chronic myeloid leukemia

Molecular Cancer volume 24, Article number: 114 (2025) Cite this article

Abstract

Blast phase chronic myeloid leukemia (BP-CML) poses significant clinical challenges due to its drug resistance, resulting from BCR::ABL1-dependent mutations and BCR::ABL1-independent pathways. Previously, we reported that FLT3 pathway is activated in ~ 50% of BP-CML cases, indicating a potential avenue for therapeutic intervention via dual inhibition of BCR::ABL1 and FLT3. Here, we aimed to evaluate the efficacy of KF1601, a dual inhibitor of BCR::ABL1 and FLT3, in overcoming drug resistance in BP-CML while also comparing its thrombo-inflammatory responses with those of ponatinib, known to have severe cardiovascular adverse events in human. Our findings revealed that KF1601 effectively inhibited of BCR::ABL1 signaling pathway, even in the presence of the T315I mutation. KF1601 achieved complete tumor regression in K562 xenograft mouse models, and prolonged survival significantly in orthotopic mouse models. Furthermore, KF1601 effectively inhibited the FLT3 signaling pathway in imatinib-resistant K562 cells expressing FLT3 and TAZ, suppressing cell proliferation through dual inhibition of BCR::ABL1 and FLT3. These findings were corroborated using drug-resistant BP-CML cells from patients. In assessing thrombo-inflammatory responses using a murine thrombosis model, ponatinib induced severe responses, leading to carotid artery occlusion and extensive vessel wall damage. In contrast, in mice treated with KF1601, carotid arteries remained unoccluded, with vessel walls preserved intact. In summary, KF1601 demonstrated promising preclinical efficacy in overcoming resistance mechanisms, including the BCR::ABL1T315I mutation, while also addressing FLT3 signaling implicated in BP-CML progression. Unlike existing therapies such as ponatinib, KF1601 offers a favorable safety profile, potentially minimizing the risk of life-threatening adverse effects.

Introduction

Chronic myeloid leukemia (CML) is a myeloproliferative neoplasm, characterized by the fusion of the ABL1 gene on chromosome 9 with the BCR gene on chromosome 22 [1]. This fusion results in the constitutive activation of the BCR::ABL1 tyrosine kinase, which drives aberrant cellular proliferation through downstream signaling pathways including RAS, MYC and STAT [2, 3]. Imatinib, the first generation tyrosine kinase inhibitor (TKI) targeting BCR::ABL1, has revolutionized CML treatment by significantly improving patients’ outcome [4,5,6,7,8,9,10]. Nevertheless, there are two clinically important unmet needs.

Firstly, resistance to imatinib may arise from mutations in the BCR::ABL1 protein, hindering the binding of imatinib to its ATP-binding site [11, 12]. While second generation TKIs such as nilotinib, radotinib, dasatinib, and bosutinib have been developed to overcome imatinib resistance, certain mutations, such as BCR::ABL1T315I, remain refractory to these therapies [12,13,14,15,16,17]. Ponatinib, a third-generation TKI, is efficacious against BCR::ABL1T315I, but is associated with life-threatening side effects such as arterial obstruction (33%), thromboembolism (6%), and heart failure (9%) [18,19,20,21,22,23,24,25].

Secondly, blast phase (BP) CML presents a significant clinical challenge due to its resistance to TKIs and high relapse rates. BP-CML is an advanced stage of the disease, marked by the proliferation of immature, undifferentiated blast-like cells in the bone marrow and peripheral blood. While the advent of TKIs has reduced the progression rate to BP-CML from 5–20% to 1–5%, prognosis remains poor, with most patients succumbing within a year of onset [26]. For instance, in a BP-CML cohort treated with ponatinib, only 23% achieved a major cytological response within six months, and the median overall survival was just seven months, underscoring the limited efficacy of current therapies [18].

The progression to BP-CML involves multiple molecular mechanisms such as β-catenin and C-MYC upregulation, oxidative DNA damage leading to genomic instability, mutations such as T315I, and epigenetic reprogramming via the polycomb repressive complex [27]. Recently, we reported that FLT3-TAZ signaling is activated in approximately 50% of BP-CML cases conferring TKI resistance [28]. In acute myeloid leukemia, it has been reported that FLT3 increases β-catenin activity, contributing to self-renewal and leukemogenesis, and that FLT3-mediated STAT5 activation upregulates C-MYC, supporting malignant progression [29, 30]. Given that β-catenin and C-MYC are key players in BP-CML progression, FLT3 activation may contribute to disease advancement through these pathways, further supporting the rationale for targeting BCR::ABL1 and FLT3 together provides novel therapeutic opportunities for FLT3+ BP-CML patients.

In this study, we aimed to evaluate the efficacy of KF1601, a dual inhibitor of BCR::ABL1 and FLT3, in overcoming TKI resistance in BP-CML. Specifically, we investigated KF1601’s efficacy in inhibiting drug-resistant mutant forms of BCR::ABL1, including BCR::ABL1T315I, and its capacity to suppress FLT3 signaling and proliferation in drug-resistant BP-CML cells, expressing FLT3 and harboring BCR::ABL1. Additionally, we aimed to compare thrombo-inflammatory responses, associated with severe cardiovascular adverse events in human, of KF1601 and ponatinib.

Results

KF1601 forms stable complexes with both native BCR::ABL1 and BCR::ABL1T315I

KF1601 forms four hydrogen bonds with native BCR-ABL1 and three hydrogen bonds with BCR::ABL1T315I. Specifically, the pyrazole ring consistently forms a hydrogen bond with the hinge site residue M318, while the amide nitrogen of KF1601 interacts with the E286 side chain. Moreover, in the native BCR:ABL1, the nitrile moiety of KF1601 forms a hydrogen bond with R386, whereas in the BCR::ABL1T315I, the nitrogen atom of the indole ring forms a hydrogen bond with S385. Both interactions contribute to enhancing KF1601’s stabilization within the ATP-binding pocket. While a hydrogen bond is formed between the nitrogen of the pyridine ring and the T315 side chain of native BCR::ABL1, this bond is absent in BCR::ABL1T315I. The computational binding energy calculations revealed that BCR::ABL1T315I exhibits a relatively higher binding energy (native BCR::ABL1 = −83.15 kcal/mole, BCR::ABL1T315I = −62.43 kcal/mole). However, it is expected that KF1601’s robust binding to BCR::ABL1T315I with three hydrogen bonds will suffice for effective inhibition. In summary, molecular docking simulations demonstrated that KF1601 forms stable complexes with both native BCR::ABL1 and BCR::ABL1T315I (Fig. 1A and B).

Fig. 1
figure 1

KF1601 forms stable complexes with BCR::ABL1 and BCR::ABL1T315I, inhibiting downstream signaling pathways and demonstrating potent in vivo efficacy. A KF1601 forms four hydrogen bonds with native BCR::ABL1. B KF1601 forms three hydrogen bonds with BCR::ABL1T315I. The magenta dashed lines represent hydrogen bond interactions. C Immunoblotting results shown in three panels: the left panel displays results from Ba/F3 parental cells, the middle panel displays results from Ba/F3 cells expressing native BCR::ABL1, and the right panel displays results from Ba/F3 cells expressing BCR::ABL1T315I. Ponatinib served as a positive control for BCR::ABL1T315I, and nilotinib as a negative control. KF1601 demonstrated dose-dependent inhibition of the downstream signaling pathway of BCR::ABL1 in both Ba/F3 cells expressing native BCR::ABL1 and Ba/F3 cells expressing BCR::ABL1T315I. D Dose–response curves for KF1601 in Ba/F3 cell line and IC50 values of KF1601 and imatinib. Ba/F3: Ba/F3 parental cells; Ba/F3BCR::ABL1: Ba/F3 cells expressing native BCR::ABL1; Ba/F3T315I: Ba/F3 cells expressing BCR::ABL1T315I; K562, TCCS, KOPM28: patient-derived CML cell lines with native BCR::ABL1; TCCST315I and KOPM28T315I: sublines of TCCS and KOPM28 with BCR::ABL1T315I. E Tumor growth inhibition in a CML xenograft mouse model using K562 human CML cells. Following cessation of KF1601 treatment, complete tumor regression was maintained in 3 out of 10 mice treated with 5 mg/kg of KF1601, and in all mice treated with either 10 mg/kg or 30 mg/kg of KF1601 until the end of the study. Each KF1601 treatment group was compared to the vehicle group based on the treatment day using GraphPad prism 10, with statistical significance (p < 0.0001). F Reduction in tumor burden in an orthotopic CML mouse model mice. The tumor burden in KF1601-treated groups was reduced by over 99% compared to that in the vehicle-treated group. **** p < 0.0001. G Post-treatment survival of orthotopic CML mice. In the KF1601-treated groups, the median survival time increased to 31–35 days, compared to 21 days in the vehicle-treated group. Curves were compared by Log-rank Mantel-Cox test (KF1601 25 mg/kg p < 0.001, Ponatinib 25 mg/kg, KF1601 50 mg/kg and KF1601 100 mg/kg p < 0.0001)

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KF1601 inhibited the downstream signaling pathway of BCR::ABL1

We investigated the effects of KF1601 on the downstream signaling pathway of BCR::ABL1 in three different types of cells: 1) parental Ba/F3 cells; 2) Ba/F3 cells with native BCR::ABL1; and 3) Ba/F3 cells with BCR::ABL1T315I. Ponatinib served as a positive control for BCR::ABL1T315I, and nilotinib as a negative control [13, 24, 25]. KF1601 downregulated the phosphorylation of CRKL, an adaptor and the major substrate of BCR::ABL1 as well as that of STAT5 and ERK, critical mediators of oncogenic transcriptional events in CML, in Ba/F3 cells with either native BCR::ABL1 or BCR::ABL1T315I in a dosage-dependent manner. Nilotinib, a second-generation TKI, inhibited the downstream signaling pathway of native BCR::ABL1, but not that of BCR::ABL1T315I (Fig. 1C).

Since CRKL phosphorylation is directly associated with the kinase activity of BCR::ABL1, we further investigated the effect of KF1601 on CRKL phosphorylation in four different cell lines: Ba/F3 cells expressing BCR::ABL1T315I, and patient-derived CML cell lines including TCCS, TCCST315I and K562. Quantitative analysis of CRKL phosphorylation demonstrated that KF1601 is a potent inhibitor of both native BCR::ABL1 and BCR::ABL1T315I (Fig. S1).

KF1601 inhibited the kinase activity of native and mutant forms of BCR::ABL1

We quantitatively assessed the inhibitory effect of KF1601 on the kinase activity of native and mutant forms of BCR::ABL1 through in vitro biochemical kinase assay. KF1601 inhibited the kinase activity of clinically important mutants of BCR::ABL1, including BCR::ABL1T315I with IC50 values ranging between 0.76 and 10.9 nM (Table S1).

KF1601 inhibited the proliferation of murine Ba/F3 and human CML cell lines with either native BCR::ABL1 or BCR::ABL1 T315I

We investigated the inhibitory effect of KF1601 on cellular proliferation using three murine Ba/F3 cell lines (i.e., parental, Ba/F3 cells expressing either native BCR::ABL1 or BCR::ABL1T315I) and five human CML cell lines (i.e., K562, TCCS, TCCST315I, KOPM28, and KOPM28T315I). Figure 1D summarizes IC50 values of KF1601 and imatinib in these eight cell lines. Both KF1601 and imatinib strongly suppressed the proliferation of Ba/F3BCR::ABL1, K562, TCCS, and KOPM28 harboring native BCR::ABL1. KF1601 strongly suppressed the proliferation of Ba/F3T315I, TCCST315I and KOPM28T315I harboring BCR::ABL1T315I, while imatinib did not.

KF1601 achieved complete tumor regression and prolonged survival in a CML xenograft mouse model

We evaluated the efficacy of KF1601 in reducing tumor burden in a CML xenograft mouse model using K562 human CML cells. K562 tumor-bearing mice received oral doses of either vehicle (N = 10) or KF1601 (5, 10, or 30 mg/kg, N = 10 per group) once daily for 18 consecutive days. We measured tumor volume to assess tumor growth inhibition, and monitored survival for 8 weeks post-treatment. As depicted in Fig. 1F, tumor growth was entirely inhibited in all KF1601-treated groups. Following the cessation of KF1601 treatment, complete tumor regression was sustained in 3 out of 10 mice treated with 5 mg/kg of KF1601, and in all mice treated with either 10 mg/kg or 30 mg/kg of KF1601 for 8 weeks (i.e., until the end of the study).

KF1601 reduced tumor burden and prolonged survival in an orthotopic CML mouse model

We evaluated the efficacy of KF1601 in reducing tumor burden in an orthotopic CML mouse model. Ba/F3 cells, engineered to co-express BCR::ABL1T315I and firefly luciferase, were intravenously injected into BALB/c nude mice. Three days post-injection, mice were randomly assigned to one of five treatment groups: vehicle (negative control), ponatinib (positive control), and three groups treated with varying doses of KF1601 (25, 50 and 100 mg/kg (N = 10 per group). Proliferation of the Ba/F3 cells was monitored using in vivo bioluminescence imaging, revealing that the tumor burden in KF1601-treated groups was reduced by over 99% compared to that in the vehicle-treated group (Fig. 1F). A reduction of over 99% in tumor burden corresponds to complete cytogenetic response in human CML treatment [31].

Following the cessation of KF1601 treatment at day 12, we monitored the survival of the five treatment groups. As depicted in Fig. 1G, we observed a median survival time of 21 days for the vehicle-treated mice, while in the KF1601-treated groups, the median survival time increased to 31–35 days, demonstrating a significant survival benefit comparable to that of ponatinib.

KF1601 inhibited FLT3 and suppressed the proliferation of BP-CML cells

In our previous study, we established two CML cell line models to demonstrate the involvement of FLT3-TAZ signaling in TKI resistance in BP-CML: 1) K562 cells overexpressing FLT3 (K562-FLT3); 2) a subline of K562-FLT3 with imatinib resistance (K562-FLT3-IR). K562-FLT3 does not express TAZ and is not resistant to imatinib while K562-FLT3-IR expresses TAZ [28].

Utilizing the same cell line models (i.e., K562-FLT3 and K562-FLT3-IR), we investigated the efficacy of KF1601 in inhibiting FLT3 signaling, in comparison to that of ponatinib. KF1601 effectively suppressed FLT3-pSTAT3-TAZ signaling and BCR::ABL1 signaling in both K562-FLT3 and K562-FLT3-IR cells (Fig. 2A and B). Furthermore, KF1601 significantly suppressed the proliferation of both K562-FLT3 and K562-FLT3-IR cells (Fig. 2C-E).

Fig. 2
figure 2

Effects of KF1601 on FLT3 signaling pathway and thrombo-inflammatory responses. A Immunoblotting analysis of FLT3 signaling pathway in K562-FLT3 cells treated with KF1601, ponatinib (Pona) for 4h. B Immunoblotting analysis of FLT3 signaling pathway in K562-FLT3-IR cells treated with KF1601, ponatinib for 17h. C Cell images of K562-FLT3 cells at day 4 post-treatment with compounds, and images of K562-FLT3-IR cells at day 6 post-treatment with compounds. D and E Cell viability measurement of K562-FLT3 cells at day 4 post-treatment with compounds (D), and that of K562-FLT3-IR cells at day 6 post-treatment with compounds (E). F and G Immunoblotting analysis of FLT3 protein in BMMCs from BP CML patients (1588(BP) and 2084(BP)). BMMCs from CP CML patients (1588(CP) and 903(CP)) were used as negative controls for FLT3 expression. H and I Immunofluorescence images of FLT3 expression (green) on the cell surface in 1588(BP) and 2084(BP) cells. 1332(CP) and 2084(CP) were used as negative controls for FLT3 expression. DAPI (blue) was used as a nuclear marker. J and K Cell viability measurement of PBMCs from normal donors and BMMCs from BP CML patients. PBMCs and BMMCs were subjected to treatment with either imatinib (J) or KF1601 (K) for 4 days. 2084 (BP) harbors BCR::ABL1 T315I mutation with a distinct FLT3 expression pattern (F); 1588 (BP) harbors BCR::ABL1 E255V mutation with a distinct FLT3 expression pattern (G). n = 3 per group. L The left panel illustrates the pivotal role of FLT3 in BP-CML progression and TKI resistance. The right panel illustrates potential of KF1601 may overcome TKI resistance by targeting mutant forms of BCR::ABL1 while also addressing the FLT3-mediated signaling pathways. L Thrombo-inflammatory responses in carotid arteries. Ponatinib induced occlusion of carotid arteries with extensive vessel wall damage. Conversely, in mice treated with KF1601, carotid arteries remained unoccluded, with the vessel walls preserved intact. M Evaluation of thrombus size in testicular arteries. The size of thrombus induced by KF1601 was approximately one-tenth that induced by ponatinib. N KDR inhibition. Ponatinib exhibited a KDR inhibition potency tenfold greater than that of KF1601

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To further evaluate the clinical relevance of our findings, We investigated the efficacy of KF1601 in bone marrow mononuclear cells (BMMCs) isolated from CML patients. Initially, we confirmed the up-regulation of FLT3 protein expression in BMMCs from BP-CML patients (i.e., 1588(BP) and 2084(BP)) compared to those from chronic phase (CP) CML patients (2F-2I). As depicted in Fig. 2J and K, both imatinib and KF1601 exhibited minimal toxicity in PBMCs (PBMC1 and PBMC2) derived from healthy donors, even at high concentrations. However, while imatinib exhibited limited efficacy against BP-CML cells with FLT3 overexpression, KF1601 demonstrated dose-dependent inhibition of their proliferation. These results underscore the potential of KF1601 as a promising therapeutic agent for both prevention of resistance acquisition driven by FLT3 upregulation and treatment post-acquisition.

Evaluation of thrombo-inflammatory responses: KF1601 versus ponatinib in a murine thrombosis model

We compared the thrombo-inflammatory effects of KF1601 with ponatinib, a drug known for its potential to induce acute ischemic and other thrombo-inflammatory responses, using a murine thrombosis model. As illustrated in Fig. 2L, ponatinib triggered severe thrombo-inflammatory responses, leading to the occlusion of carotid arteries with extensive vessel wall damage. In contrast, in mice treated with KF1601, carotid arteries remained unoccluded, with the vessel walls preserved intact. To further evaluate thrombus size, thrombosis was induced in testicular arteries. The average size score of thrombi induced by KF1601 was 3.24, whereas that induced by ponatinib was 5.21. A size score of 3 indicates a medium-sized thrombus (measuring 75—150 × 75—150nm2), while a size score of 5 indicates an extra-large thrombus (measuring 300 – 400 × 300 – 400 nm2). In simpler terms, the size of thrombus induced by KF1601 was approximately one-tenth that induced by ponatinib (Fig. 2M).

Evaluation of KDR and platelet function inhibition: KF1601 versus ponatinib

KDR inhibition and platelet dysfunction are recognized contributors to thrombo-inflammatory responses. KDR inhibition triggers endothelial cell damage, culminating in thrombosis [32]. As depicted in Fig. 2N, ponatinib demonstrated a KDR inhibition potency tenfold greater than that of KF1601. In addition, we conducted kinome analyses to compare the overall selectivity of KF1601 and ponatinib. As summarized in Supplementary Table 2, KF1601 exhibited greater selectivity compared to ponatinib.

Platelet dysfunction in normal physiological conditions often results in platelet aggregation, promoting thrombosis. As summarized in Supplementary Table 3, ponatinib inhibited platelet function by more than 90% while KF1601 inhibited platelet function by approximately 25%, comparable to imatinib, a drug known for relatively low cardiovascular toxicity and arterial thrombotic event rate.

Discussion

In this study, we demonstrated the preclinical efficacy of KF1601, a novel dual inhibitor of BCR::ABL1 and FLT3, in addressing the unmet needs of CML treatment. KF1601 exhibited potent inhibitory activity against native BCR::ABL1 and clinically meaningful mutant forms, including BCR::ABL1T315I. This broad spectrum of activity holds promise for overcoming resistance associated with BCR::ABL1 mutations, offering a potential therapeutic option for patients with refractory disease.

Importantly, our study also highlights the role of FLT3 pathway activation in promoting TKI resistance in BP-CML. Activation of FLT3 signaling has been implicated in promoting leukemic cell proliferation and survival, particularly in the context of BP-CML [33]. By targeting both BCR::ABL1 and FLT3, KF1601 demonstrated synergistic anti-leukemic effects, as evidenced by its ability to induce cell death in FLT3 + BCR::ABL1 TKI-resistant CML cells. These findings underscore the potential clinical utility of KF1601 in addressing the therapeutic challenges associated with BP-CML, where conventional TKIs may fall short. Also, as Copland [27] emphasized, due to poor outcomes of BP-CML, we need to focus on preventing the progression to BP-CML. The ability of KF1601 to concurrently inhibit both BCR::ABL1 and FLT3 signaling pathways has the potential to mitigate the development of BP-CML cells, offering a novel therapeutic strategy for preventing disease progression and improving patient outcomes.

While ponatinib demonstrated efficacy in inhibiting both BCR::ABL1 and FLT3, thereby potentially addressing the therapeutic challenges associated with BP-CML, its clinical utility is hindered by significant limitations. The occurrence of life-threatening adverse effects, including arterial obstruction, thromboembolism, and heart failure, underscores the need for alternative treatment options [20]. In contrast, KF1601 presents a promising alternative with a favorable safety profile observed in preclinical studies. The ability of KF1601 to simultaneously target BCR::ABL1 and FLT3, coupled with its oral bioavailability and potential for reduced adverse effects, positions it as a compelling candidate for the management of BP-CML. Additionally, the development of KF1601 offers the possibility of addressing the unmet needs of CML patients resistant to first- and second-generation TKIs, including those harboring the BCR::ABL1T315I mutation, without compromising on safety or efficacy. Further clinical investigation is warranted to validate the therapeutic benefits of KF1601 in BP-CML and to delineate its comparative advantages over existing treatment modalities, including ponatinib.

Conclusion

The emergence of TKI resistance and the clinical complexities associated with BP-CML underscore the urgent need for novel therapeutic approaches. KF1601, a dual inhibitor targeting both BCR::ABL1 and FLT3, demonstrates promising preclinical efficacy in overcoming resistance mechanisms, including the notorious BCR::ABL1T315I mutation, while also addressing FLT3-mediated signaling implicated in BP-CML progression (Supplementary Fig. 2). Unlike existing therapies such as ponatinib, KF1601 offers a favorable safety profile, potentially minimizing the risk of life-threatening adverse effects. Future clinical studies are warranted to validate the therapeutic benefits of KF1601 in TKI-resistant chronic and blast phase CML.

Data availability

 All data associated with this study are present in the paper or the Supplementary Materials. 

Abbreviations

BCR::ABL1:

BCR::ABL1 Fusion gene (Breakpoint Cluster Region gene and ABL Proto-Oncogene 1)

FLT3:

Fms Related Receptor Tyrosine Kinase 3

TAZ:

Transcriptional coactivator with PDZ-binding motif

CML:

Chronic myeloid leukemia

AML:

Acute myeloid leukemia

TKI:

Tyrosine kinase inhibitor

BMMCs:

Bone marrow mononuclear cells

CP:

Chronic phase

AP:

Accelerated phase

BP:

Blast phase

TKD:

Tyrosine kinase domain

References

  1. Heisterkamp N, Stam K, Groffen J, de Klein A, Grosveld G. Structural organization of the bcr gene and its role in the Ph’ translocation. Nature. 1985Jul 27;315(6022):758–61.

    Article  CAS  PubMed  Google Scholar 

  2. Mandanas RA, Leibowitz DS, Gharehbaghi K, Tauchi T, Burgess GS, Miyazawa K, Jayaram HN, Boswell HS. Role of p21 RAS in p210 bcr-abl transformation of murine myeloid cells. Blood. 1993Sep 15;82(6):1838–47.

    Article  CAS  PubMed  Google Scholar 

  3. Raitano AB, Halpern JR, Hambuch TM, Sawyers CL. The Bcr-Abl leukemia oncogene activates Jun kinase and requires Jun for transformation. Proc Natl Acad Sci U S A. 1995Dec 5;92(25):11746–50.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  4. Capdeville R, Buchdunger E, Zimmermann J, Matter A. Glivec (STI571, imatinib), a rationally developed, targeted anticancer drug. Nat Rev Drug Discov. 2002Jul;1(7):493–502.

    Article  CAS  PubMed  Google Scholar 

  5. Mauro MJ, Druker BJ. STI571: targeting BCR-ABL as therapy for CML. Oncologist. 2001;6(3):233–8.

    Article  CAS  PubMed  Google Scholar 

  6. Bendit I, Sanabani SS, Conchon M, Serpa M, Novaes MMY, Nardinelli L, Pereira TDM, Tucunduva L, Ferreira P de B, Dorlhiac-Llacer PE, Chamone D de AF. Evaluation of Long-Term Outcomes, Cytogenetic and Molecular Responses with Imatinib Mesylate in Early and Late Chronic-Phase Chronic Myeloid Leukemia: A Report from a Single Institute. AHA. 2012;128(4):223–32.

  7. Druker BJ, Talpaz M, Resta DJ, Peng B, Buchdunger E, Ford JM, Lydon NB, Kantarjian H, Capdeville R, Ohno-Jones S, Sawyers CL. Efficacy and safety of a specific inhibitor of the BCR-ABL tyrosine kinase in chronic myeloid leukemia. N Engl J Med. 2001Apr 5;344(14):1031–7.

    Article  CAS  PubMed  Google Scholar 

  8. Druker BJ, Guilhot F, O’Brien SG, Gathmann I, Kantarjian H, Gattermann N, Deininger MWN, Silver RT, Goldman JM, Stone RM, Cervantes F, Hochhaus A, Powell BL, Gabrilove JL, Rousselot P, Reiffers J, Cornelissen JJ, Hughes T, Agis H, Fischer T, Verhoef G, Shepherd J, Saglio G, Gratwohl A, Nielsen JL, Radich JP, Simonsson B, Taylor K, Baccarani M, So C, Letvak L, Larson RA, IRIS Investigators. Five-year follow-up of patients receiving imatinib for chronic myeloid leukemia. N Engl J Med. 2006;355(23):2408–17.

  9. Kantarjian H, Sawyers C, Hochhaus A, Guilhot F, Schiffer C, Gambacorti-Passerini C, Niederwieser D, Resta D, Capdeville R, Zoellner U, Talpaz M, Druker B, Goldman J, O’Brien SG, Russell N, Fischer T, Ottmann O, Cony-Makhoul P, Facon T, Stone R, Miller C, Tallman M, Brown R, Schuster M, Loughran T, Gratwohl A, Mandelli F, Saglio G, Lazzarino M, Russo D, Baccarani M, Morra E, International STI571 CML Study Group. Hematologic and cytogenetic responses to imatinib mesylate in chronic myelogenous leukemia. N Engl J Med. 2002;346(9):645–52.

  10. Druker BJ. Imatinib as a Paradigm of Targeted Therapies. In: Advances in Cancer Research. Elsevier; 2004 [cited 2020 Sep 3]. p. 1–30. Available from: https://linkinghub.elsevier.com/retrieve/pii/S0065230X04910019.

  11. Shah NP, Nicoll JM, Nagar B, Gorre ME, Paquette RL, Kuriyan J, Sawyers CL. Multiple BCR-ABL kinase domain mutations confer polyclonal resistance to the tyrosine kinase inhibitor imatinib (STI571) in chronic phase and blast crisis chronic myeloid leukemia. Cancer Cell. 2002Aug;2(2):117–25.

    Article  CAS  PubMed  Google Scholar 

  12. O’Hare T, Eide CA, Deininger MWN. Bcr-Abl kinase domain mutations, drug resistance, and the road to a cure for chronic myeloid leukemia. Blood. 2007Oct 1;110(7):2242–9.

    Article  PubMed  Google Scholar 

  13. Weisberg E, Manley P, Mestan J, Cowan-Jacob S, Ray A, Griffin JD. AMN107 (nilotinib): a novel and selective inhibitor of BCR-ABL. Br J Cancer. 2006Jun 19;94(12):1765–9.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  14. Kim SH, Menon H, Jootar S, Saikia T, Kwak JY, Sohn SK, Park JS, Jeong SH, Kim HJ, Kim YK, Oh SJ, Kim H, Zang DY, Chung JS, Shin HJ, Do YR, Kim JA, Kim DY, Choi CW, Park S, Park HL, Lee GY, Cho DJ, Shin JS, Kim DW. Efficacy and safety of radotinib in chronic phase chronic myeloid leukemia patients with resistance or intolerance to BCR-ABL1 tyrosine kinase inhibitors. Haematologica. 2014Jul;99(7):1191–6.

    Article  PubMed  PubMed Central  Google Scholar 

  15. Imagawa J, Tanaka H, Okada M, Nakamae H, Hino M, Murai K, Ishida Y, Kumagai T, Sato S, Ohashi K, Sakamaki H, Wakita H, Uoshima N, Nakagawa Y, Minami Y, Ogasawara M, Takeoka T, Akasaka H, Utsumi T, Uike N, Sato T, Ando S, Usuki K, Morita S, Sakamoto J, Kimura S. Discontinuation of dasatinib in patients with chronic myeloid leukaemia who have maintained deep molecular response for longer than 1 year (DADI trial): a multicentre phase 2 trial. The Lancet Haematology. 2015Dec 1;2(12):e528–35.

    Article  PubMed  Google Scholar 

  16. Cortes JE, Kantarjian HM, Brümmendorf TH, Kim DW, Turkina AG, Shen ZX, Pasquini R, Khoury HJ, Arkin S, Volkert A, Besson N, Abbas R, Wang J, Leip E, Gambacorti-Passerini C. Safety and efficacy of bosutinib (SKI-606) in chronic phase Philadelphia chromosome-positive chronic myeloid leukemia patients with resistance or intolerance to imatinib. Blood. 2011Oct 27;118(17):4567–76.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  17. Eckart F, Tauer JT, Suttorp M, Knöfler R. Impact of Tyrosine Kinase Inhibitors Applied for First-Line Chronic Myeloid Leukemia Treatment on Platelet Function in Whole Blood of Healthy Volunteers In Vitro. Hamostaseologie. 2023Jun;43(3):179–87.

    Article  PubMed  Google Scholar 

  18. Cortes JE, Kim DW, Pinilla-Ibarz J, le Coutre PD, Paquette R, Chuah C, Nicolini FE, Apperley JF, Khoury HJ, Talpaz M, DeAngelo DJ, Abruzzese E, Rea D, Baccarani M, Müller MC, Gambacorti-Passerini C, Lustgarten S, Rivera VM, Haluska FG, Guilhot F, Deininger MW, Hochhaus A, Hughes TP, Shah NP, Kantarjian HM. Ponatinib efficacy and safety in Philadelphia chromosome–positive leukemia: final 5-year results of the phase 2 PACE trial. Blood. 2018Jul 26;132(4):393–404.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  19. Frankfurt O, Licht JD. Ponatinib—A Step Forward in Overcoming Resistance in Chronic Myeloid Leukemia. Clin Cancer Res. 2013Oct 31;19(21):5828–34.

    Article  CAS  PubMed  Google Scholar 

  20. Hamadi A, Grigg AP, Dobie G, Burbury KL, Schwarer AP, Kwa FA, Jackson DE. Ponatinib Tyrosine Kinase Inhibitor Induces a Thromboinflammatory Response. Thromb Haemost. 2019Jul;119(7):1112–23.

    Article  PubMed  Google Scholar 

  21. Latifi Y, Moccetti F, Wu M, Xie A, Packwood W, Qi Y, Ozawa K, Shentu W, Brown E, Shirai T, McCarty OJ, Ruggeri Z, Moslehi J, Chen J, Druker BJ, López JA, Lindner JR. Thrombotic microangiopathy as a cause of cardiovascular toxicity from the BCR-ABL1 tyrosine kinase inhibitor ponatinib. Blood. 2019;133(14):1597–606.

  22. Loren CP, Aslan JE, Rigg RA, Nowak MS, Healy LD, Gruber A, Druker BJ, McCarty OJT. The BCR-ABL inhibitor ponatinib inhibits platelet immunoreceptor tyrosine-based activation motif (ITAM) signaling, platelet activation and aggregate formation under shear. Thromb Res. 2015Jan;135(1):155–60.

    Article  CAS  PubMed  Google Scholar 

  23. Merkulova A, Mitchell SC, Stavrou EX, Forbes GL, Schmaier AH. Ponatinib treatment promotes arterial thrombosis and hyperactive platelets. Blood Adv. 2019Aug 13;3(15):2312–6.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  24. Hanley MJ, Diderichsen PM, Narasimhan N, Srivastava S, Gupta N, Venkatakrishnan K. Population Pharmacokinetics of Ponatinib in Healthy Adult Volunteers and Patients With Hematologic Malignancies and Model-Informed Dose Selection for Pediatric Development. J Clin Pharmacol. 2022Apr;62(4):555–67.

    Article  CAS  PubMed  Google Scholar 

  25. Cortes JE, Kantarjian H, Shah NP, Bixby D, Mauro MJ, Flinn I, O’Hare T, Hu S, Narasimhan NI, Rivera VM, Clackson T, Turner CD, Haluska FG, Druker BJ, Deininger MWN, Talpaz M. Ponatinib in refractory Philadelphia chromosome-positive leukemias. N Engl J Med. 2012Nov 29;367(22):2075–88.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  26. Bonifacio M, Stagno F, Scaffidi L, Krampera M, Di Raimondo F. Management of Chronic Myeloid Leukemia in Advanced Phase. Front Oncol. 2019 Oct 25 [cited 2025 Feb 6];9. Available from: https://www.frontiersin.org/journals/oncology/articles/10.3389/fonc.2019.01132/full.

  27. Copland M. Treatment of blast phase chronic myeloid leukaemia: A rare and challenging entity. Br J Haematol. 2022;199(5):665–78.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  28. Shin JE, Kim SH, Kong M, Kim HR, Yoon S, Kee KM, Kim JA, Kim DH, Park SY, Park JH, Kim H, No KT, Lee HW, Gee HY, Hong S, Guan KL, Roe JS, Lee H, Kim DW, Park HW. Targeting FLT3-TAZ signaling to suppress drug resistance in blast phase chronic myeloid leukemia. Mol Cancer. 2023Nov 6;22(1):177.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  29. Jiang X, Mak PY, Mu H, Tao W, Mak DH, Kornblau S, Zhang Q, Ruvolo P, Burks JK, Zhang W, McQueen T, Pan R, Zhou H, Konopleva M, Cortes J, Liu Q, Andreeff M, Carter BZ. Disruption of Wnt/β-Catenin Exerts Antileukemia Activity and Synergizes with FLT3 Inhibition in FLT3-Mutant Acute Myeloid Leukemia. Clin Cancer Res. 2018May 14;24(10):2417–29.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  30. Spiekermann K, Bagrintseva K, Schwab R, Schmieja K, Hiddemann W. Overexpression and Constitutive Activation of FLT3 Induces STAT5 Activation in Primary Acute Myeloid Leukemia Blast Cells1. Clin Cancer Res. 2003Jun 1;9(6):2140–50.

    CAS  PubMed  Google Scholar 

  31. Kantarjian H, Deisseroth A, Kurzrock R, Estrov Z, Talpaz M. Chronic myelogenous leukemia: a concise update. Blood. 1993Aug 1;82(3):691–703.

    Article  CAS  PubMed  Google Scholar 

  32. Izzedine H, Massard C, Spano JP, Goldwasser F, Khayat D, Soria JC. VEGF signalling inhibition-induced proteinuria: Mechanisms, significance and management. Eur J Cancer. 2010Jan 1;46(2):439–48.

    Article  CAS  PubMed  Google Scholar 

  33. Kazi JU, Rönnstrand L. FMS-like Tyrosine Kinase 3/FLT3: From Basic Science to Clinical Implications. Physiol Rev. 2019Jul;99(3):1433–66.

    Article  CAS  PubMed  Google Scholar 

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Funding

This work was supported by the National Research Foundation of Korea (NRF-2017M3A9G4052951 to S.M.A., and RS-2025-00556619, RS-2024-00509461 to H.W.P., and RS-2020-NR046179 to D.W.K.), and by grant of the Korea Health Technology R&D Project through the Korea Health Industry Development Institute (KHIDI), funded by the Ministry of Health & Welfare, Republic of Korea (Grant Number: HI19C0760 and HI22C2117 to S.M.A.).

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Author notes

  1. Hyun-Jin Kwon, Ji Eun Shin, Amir Khan and So Yeon Park contributed equally to this work.

Authors and Affiliations

  1. ImmunoForge, Co. Ltd, Seoul, 08591, Republic of Korea

    Hyun-Jin Kwon, Jiyoung Kim & Sung-Min Ahn

  2. Department of Biochemistry, College of Life Science and Biotechnology, Brain Korea 21 FOUR Program, Yonsei University, Seoul, 03722, Republic of Korea

    Ji Eun Shin, So Yeon Park & Hyun Woo Park

  3. Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA

    Amir Khan

  4. Daegu-Gyeongbuk Medical Innovation Foundation, New Drug Development Center, Daegu, 41061, Republic of Korea

    Jee-Young Lee, Doohyun Lee, Seungyeon Lee, Chun Young Im & Heegyum Moon

  5. Department of Chemistry, College of Science and Technology, Duksung Women’S University, Seoul, 01369, Republic of Korea

    Ye Ri Han

  6. Department of Pediatrics, University of Yamanashi, Chuo, Japan

    Minori Tamai, Koshi Akahane & Takeshi Inukai

  7. Department of Chemistry, Sungkyunkwan University, Suwon, 16419, Republic of Korea

    Wonhwa Lee

  8. Brain Science Institute, Korea, Institute of Science and Technology (KIST), Seoul, 02792, Republic of Korea

    Hyelim Kim & Hong Nam Kim

  9. Department of Genome Medicine and Science, College of Medicine, Gachon University, Incheon, 21565, Republic of Korea

    Sung-Min Ahn

  10. Hematology Department, Eulji Medical Center, Eulji University, Uijeongbu-Si, Gyeonggi-Do, Republic of Korea

    Dong-Wook Kim

  11. Leukemia Omics Research Institute, Eulji University, Uijeongbu‑si, Gyeonggi‑Do, Republic of Korea

    Dong-Wook Kim

  12. Department of Biotechnology, Yonsei University, Seoul, 03722, Republic of Korea

    Hyelim Kim

  13. Division of Bio-Medical Science and Technology (KIST School), Korea University of Science and Technology (UST), Seoul, 02792, Republic of Korea

    Hong Nam Kim

  14. School of Mechanical Engineering, Yonsei University, Seoul, 03722, Republic of Korea

    Hong Nam Kim

  15. Yonsei-KIST Convergence Research Institute, Yonsei University, Seoul, 03722, Republic of Korea

    Hong Nam Kim

  16. Global Leukemia Cell-Line Assembly Network, University of Yamanashi, Kofu City, Japan

    Koshi Akahane & Takeshi Inukai

Authors
  1. Hyun-Jin Kwon
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  2. Ji Eun Shin
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  3. Amir Khan
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Contributions

HJK performed most experiments related to BCR::ABL1; JES and SYP performed most experiments related to FLT3 signaling. AK performed bioinformatics analysis and wrote the manuscript. JYK designed the animal experiments. JYL performed molecular modeling study. DHL, SYL, CYI, and YRH synthesized chemical compounds. HGM established Ba/F3 cell lines and performed cell-based experiments. WHL performed experiments related to thrombo-inflammatory responses. MT, KA and TI established and provided human CML cell lines with T315I mutation. SMA, HWP, and DWK conceived the project, provided leadership, and wrote the manuscript. All authors reviewed and edited the manuscript.

Corresponding authors

Correspondence to Sung-Min Ahn, Hyun Woo Park or Dong-Wook Kim.

Ethics declarations

Ethics approval and consent to participate

All human samples were obtained from the Korea Leukemia Bank and the protocol was approved by the Institutional Review Board. Patient consent was obtained in accordance with the Declaration of Helsinki. Animal experiments were approved by Institutional Animal Care and Use Committee (IACUC), the preclinical research center, Daegu-Gyeongbuk Medical Innovation Foundation (Documentation KMEDI-22011801–01).

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Not applicable.

Competing interests

HJK, JYK, and SMA are employees of ImmunoForge, Inc., and KF1601 is a proprietary drug candidate of ImmunoForge, Inc. The remaining authors declare no conflict of interests.

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Kwon, HJ., Shin, J.E., Khan, A. et al. KF1601, a dual inhibitor of BCR::ABL1 and FLT3, overcomes drug resistance in FLT3+ blast phase chronic myeloid leukemia. Mol Cancer 24, 114 (2025). https://doiorg.publicaciones.saludcastillayleon.es/10.1186/s12943-025-02292-z

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Keywords

Molecular Cancer

ISSN: 1476-4598