Treatment Of Chronic Myeloid Leukemia Research Articles

Cardiovascular complications associated with asciminib use: A retrospective analysis.

6563 Background: Asciminib, a newly developed drug, has shown promising results in the treatment of several diseases. It is a cellular tyrosine kinase inhibitor (TKI) that specifically targets ABL myristoyl pocket (STAMP) inhibitor, responsible for the malignant growth and proliferation of leukemia cells in chronic myeloid leukemia (CML) patients, assuring a positive treatment of CML. However, as with all medications, there are possible side effects that must be carefully monitored. In comparison to Ponatinib (tyrosine kinase inhibitor) which is extensively used to treat CML and exhibits a cardiovascular risk profile, cardiovascular side effects with the use of Asciminib are rarely reported in literature, prompting its use in patients at a higher risk of these events. Through this study, we aim to highlight the cardiovascular complications associated with the use of Asciminib by integrating patient experience and clinical research. Methods: A publicly available FDA Adverse Events Reporting System (FAERS) database was utilized to review cardiovascular events associated with the use of Asciminib in patients with Chronic Myeloid leukemia (CML) between 2018-2023. Cardiovascular events such as coronary artery disease (CAD), peripheral arterial disease (PAD), and cerebrovascular accidents (CVA) were reviewed. The study focused only on adverse events reported by healthcare providers and observed in adults (above 18 years old). Results: We identified a total of 563 adverse events pertaining to the use of Asciminib in patients with CML. Of which, 63 were cardiovascular events, contributing to 11.2% of the total adverse events. Out of the reported cardiovascular side effects, 29 (46%) were due to CAD, 6 (9.5%) were due to PAD, and 28 (44.45%) were due to CVA. The mortality rate amongst patients who experienced cardiovascular side effects was 11%. Moreover, cardiovascular events contributed to 7% of all mortality associated with the use of Asciminib, with CAD contributing to most of the deaths. Conclusions: It is imperative to consider the potential of cardiovascular events in patients initiated on Asciminib. This study emphasizes the importance of using patient records and medical research to obtain complete information. Patients with underlying risk factors for the development of cardiovascular diseases should be thoroughly evaluated before drug initiation. The minimum threshold for drug discontinuation should be considered in patients with suspected heart disease.

Derivatives of D(−) glutamine-based MMP-2 inhibitors as an effective remedy for the management of chronic myeloid leukemia-Part-I: Synthesis, biological screening and in silico binding interaction analysis

Chronic myeloid leukemia (CML) is a global issue and the available drugs such as tyrosine kinase inhibitors (TKIs) comprise various toxic effects as well as resistance and cross-resistance. Therefore, novel molecules targeting specific enzymes may unravel a new direction in antileukemic drug discovery. In this context, targeting gelatinases (MMP-2 and MMP-9) can be an alternative option for the development of novel molecules effective against CML. In this article, some D(−)glutamine derivatives were synthesized and evaluated through cell-based antileukemic assays and tested against gelatinases. The lead compounds, i.e., benzyl analogs exerted the most promising antileukemic potential showing nontoxicity in normal cell line including efficacious gelatinase inhibition. Both these lead molecules yielded effective apoptosis and displayed marked reductions in MMP-2 expression in the K562 cell line. Not only that, but both of them also revealed effective antiangiogenic efficacy. Importantly, the most potent MMP-2 inhibitor, i.e., benzyl derivative of p-tosyl D(−)glutamine disclosed stable binding interaction at the MMP-2 active site correlating with the highly effective MMP-2 inhibitory activity. Therefore, such D(−)glutamine derivatives might be explored further as promising MMP-2 inhibitors with efficacious antileukemic profiles for the treatment of CML in the future.

Quantifying the financial impact of treatment intolerance in chronic myeloid leukemia on oncology clinical practices: A mixed methods study.

e18520 Background: Tyrosine kinase inhibitors (TKIs) have changed the prognosis for patients with chronic myeloid leukemia (CML) to a chronic disease. However, adverse events related to TKI treatment intolerance frequently occur. While the impact of CML treatment intolerance on patient quality of life and cost to health insurers has previously been measured, the time and cost impact to oncology practices is unknown. This mixed methods study aimed to estimate the average time and cost to oncology practices per CML treatment intolerance episode. Methods: The study combined interviews of oncology practice staff with economic modeling. A convenience sample of oncology practice managers was interviewed between October 2023 - January 2024. Interviews aimed to identify and quantify the cost dimensions of addressing treatment intolerance in CML patients. Time impacts reported by respondents were converted into monetary terms using hourly compensation rates of staff needed to complete the identified task. Results: A total of 10 academic oncology practice managers participated in the study. Eight cost dimensions were identified including time spent on prior authorization for medication switch, patient communication, follow-up visits, and care coordination after inpatient stays. Estimated practice time and cost per treatment intolerance episode requiring hospitalization were 34 hours and $3,413 (Table), which were largely attributable to navigating payer prior authorization for medication switch (10 hours, $871), additional follow-up visits (8 hours, $858) and care coordination with inpatient team (9 hours, $782). Activities that could be coded for reimbursement represented only 31.9% of incurred cost. The time and cost per treatment intolerance episode requiring no hospitalization were 17 hours and $1,772. Other burdens not explicitly quantified included negative impact on patient satisfaction, staff morale and care continuity. Conclusions: CML treatment intolerance imposes additional resource and economic burden on oncology practices, and most of these activities are not reimbursed in the current healthcare system. [Table: see text]

Current Status and Management of Chronic Myeloid Leukemia in the Gulf Region: Survey Results and Expert Opinion.

Studies on chronic myeloid leukemia (CML) in the Gulf region are scarce, consisting of a survey and expert meeting that included 15 experts in 2023 which discussed CML diagnosis, testing, treatment objectives, toxicities, and discontinuation in the Gulf region. Most patients were reported to be in first-line therapy, and the most common treatments were imatinib/imatinib generic in first-line and dasatinib in second- and third-lines. Mutation analysis was not reported to be routinely performed at the time of diagnosis but rather in case of progression to accelerated/blast phase or any sign of loss of response. While all participants were aware that BCR-ABL should be monitored every three months during the first year of treatment, 10% reported monitoring BCR-ABL every six months in practice due to test cost and lab capability. The most important first-line therapy objective was "achievement of major molecular response" (MMR) in younger patients and "overall survival" in older ones. The most important treatment objectives were "MMR" and "early molecular response followed by prolongation of overall survival" in the short term and "treatment-free remission" in the long term. The current practices in CML in the Gulf region appear to be similar to global figures.

An association between Dasatinib, elevated left atrial pressure and pleural effusion

BackgroundTyrosine kinase inhibitors (TKI), such as Dasatinib, are effective in the treatment of chronic myeloid leukemia (CML) but associated with development of pleural effusions (PE). The relationship between haemodynamic parameters identified on transthoracic echocardiogram (TTE) such as elevated estimated left atrial pressure (LAP), and PE development is unknown. This study aims to describe associations between Dasatinib, elevated LAP and PE. MethodsThis was a retrospective study of 71 CML patients who underwent TTE during treatment with various TKIs. Descriptive analysis was performed to identify associations between TKI use, PE and elevated LAP on TTE. Multivariate logistic regression was performed to identify predictors of elevated LAP. ResultsThere were 36 patients treated with Dasatinib, 15 Nilotinib, and 20 Imatinib. Those treated with Dasatinib had higher rates of elevated LAP (44% vs 7% Nilotinib vs 10% Imatinib, p < 0.01) and PE (39% vs 7% vs 0%, p < 0.01). In the 15 patients who developed PE, 14 (93%) patients were treated with Dasatinib. Patients with PE had higher rates of elevated LAP (67% vs 16%, p < 0.01). Nineteen (26.8%) patients in the entire cohort had elevated LAP. After multivariate adjustment, Dasatinib (OR 33.50, 95% CI = 4.99–224.73, p < 0.01) and age (OR 1.12, 95% CI = 1.04–1.20, p < 0.01) were associated with elevated LAP. ConclusionsAmong patients with CML, there was an association between Dasatinib use, PE and elevated LAP on TTE. These findings are hypothesis generating and further studies are required to evaluate the utility of elevated LAP on TTE as a novel marker for prediction and surveillance of PE.

Analytical control of imatinib in bioanalytical samples using graphene quantum dots sensing.

An analytical method for the determination of imatinib (IMA, the primary treatment for chronic myeloid leukemia), based on the fluorescence properties of graphene quantum dots (GQDs), is reported in this work. The method is addressed to the analytical control of IMA in biological and pharmaceutical samples, due to the present interest in the control of the doses of this anticancer drug, as well as the therapeutic monitoring. The whole method involves the use of a solid-phase extraction (SPE) procedure, followed by an evaporation step, for the treatment of biological samples. For that, tC18 sorbent cartridges were used. After the sample treatment, the solution containing the analyte was mixed with an aqueous solution of GQDs at pH 7.2, and the fluorescent quenching of GQDs was measured. IMA was determined in the 10-250µgL-1 range, with a limit of detection of 21µgL-1 and a precision of 1.5% as relative standard deviation, measured in terms of reproducibility. The recovery for biological samples was in the 84-113% range.

Determination of the therapeutic effects of apigenin on chronic myeloid leukemia stem cells; a mechanistic approach

Aims: Chronic myeloid leukemia (CML) is a type of leukemia characterized by the Philadelphia (Ph) chromosome encoding the BCR-ABL protein. Significant success has been achieved in the treatment of CML with the development of agents that target this protein and inhibit its activity, but the resistance that develops in patients against these drugs limits absolute success. One of the main reasons for the resistance problem is the ineffectiveness of current therapies for CML stem cells. Apigenin (4',5,7- trihydroxyflavone) is a flavanoid found in various vegetables and fruits and has the effects of suppressing proliferation and inducing apoptosis in different cancer types. In this study, we aimed to determine the therapeutic potential of apigenin on K562 CML stem cells. Methods: The effects of apigenin on the proliferation of K562 CML stem cells were determined by an XTT cell proliferation assay. Apoptotic effects of apigenin on K562 CML stem cells were determined by changes in mitochondrial membrane potential (MZP), caspase-3 enzyme activity, and the Annexin-V method using flow cytometry. Results: The proliferation of K562 CML stem cells exposed to increasing doses of Apigenin (1-40 nM) for 48 hours decreased dose-dependently, and the IC50 value of Apigenin was calculated at 3 nM. Compared to the control group, an increase in caspase-3 enzyme activity was calculated in stem cells treated with apigenin at the same doses. Disruptions in the mitochondrial membrane potential of Apigenin-treated CML stem cells and Annexin-V assay results also showed that Apigenin dose-dependently induced apoptosis and caused significant increases in the apoptotic cell population. Conclusion: It was shown for the first time in this study that apigenin may have therapeutic effects on CML stem cells. It was determined that this effect of apigenin was achieved by triggering caspase-3 enzyme activity and disruptions in the mitochondrial membrane.

Global DNA Methylation analysis of imatinib resistant and sensitive K562 cells

OBJECTIVE: Chronic myeloid leukemia (CML) is a hematological disease which is known by the presence of Philadelphia chromosome (Ph+). BCR-ABL protein is expressed by Ph+ chromosome, represents constant increased tyrosine kinase activity. Imatinib (IMA) is a tyrosine kinase inhibitor (TKI) which is utilized as a first line treatment in CML. Emergence of IMA resistance at some point of therapy leads to treatment failure. DNA methylation is considered to be the most stable epigenetic change and several studies have shown that epigenetic changes may play a role in drug resistance. We investigated the global methylation profile of IMA-sensitive K562S, IMA-resistant K562R and IMA-resistant and adherent K562R (K562R-adh) cells to determine whether epigenetic reprogramming is involved in the resistance to IMA and the change in phenotype due to this resistance. MATERIAL AND METHODS: In this study, morphologically distinct, IMA-sensitive K562S and 5µM IMA-resistant K562R and K562R-adh in-vitro CML cell models were used to analyze the global DNA methylation profile. After DNA was isolated from the cells, global 5mC DNA methylation profiles were investigated by ELISA using equal amounts of DNA. RESULTS: Compared to K562S, the global methylation of K562R showed an increase in DNA methylation profile, but this increase in methylation was not statistically significant. Whereas, a slight hypermethylation was observed in the DNA of the K562R-adh vs K562S and K562R-adh vs K562R which is statistically significant. We observed slight hypermethylation in IMA-resistant cells lines versus to the IMA-sensitive cell line. CONCLUSION: Our observed differences in 5methyl-Cytosine on CpG islands (5mC) in K562S versus K562R and K562R-adh cell lines suggest that the DNA methylation alteration in resistant cells may partly contributed in phenotype switching.

Real World Outcomes with Treatment Free Remission in Chronic Myeloid Leukemia-Experience from a Tertiary Care Cancer Centre.

Chronic myeloid leukaemia (CML) is caused by balanced translocation t(9::22)(q34;q11) resulting in formation of pathogenic BCR-ABL fusion gene. Tyrosine kinase inhibitors (TKI) have revolutionised the treatment of CML. Ongoing treatment with TKI leads to side effects and has financial impact. Teratogenic potential of TKI and growth disturbance also represent an important challenge. Thus, TKI discontinuation in form of treatment free remission (TFR) has emerged as a new and important therapeutic goal. In this retrospective study, we reviewed CML patients who were kept on TFR. Inclusion criteria was patient age ≥ 18years diagnosed with CML in chronic phase who met the criteria for TFR and opted for same and who were in DMR but stopped TKI for any reason. We analysed the data for baseline characteristics, molecular relapse (MR), survival without molecular relapse (SWMR), TFR duration and factors affecting MR. We included 38 patients in this analysis. Thirty five (92%) patients were treated with imatinib at diagnosis. Median duration of TKI treatment was 135months. 37 patients (97.5%) achieved DMR on TKI and median time from TKI initiation to DMR was 96months. Median duration of DMR prior to TKI discontinuation was 41months. TKI was discontinued after counselling for TFR in 26 patients (68%) while it was discontinued due to intolerance in 10 patients (29%). At median molecular follow up of 25months, nine patients (23.7%) had molecular relapse. Median SWMR was not reached and 2year estimated SWMR was 65.2% (95%CI,47.2- 83.2). Of all relapses, 5/9 (55.5%) occurred in the first six months of TFR. On univariate analysis, duration of TKI and duration of DMR were predictive of molecular relapse. On multivariate analysis, none of these factors were found to be significant. This retrospective study suggests that for CML CP patients achieving deep molecular response, discontinuing TKI therapy in real-world settings may be feasible while potentially achieving comparable outcomes.

New Inhibitors of Bcr-Abl Based on 2,6,9-Trisubstituted Purine Scaffold Elicit Cytotoxicity in Chronic Myeloid Leukemia-Derived Cell Lines Sensitive and Resistant to TKIs.

Bcr-Abl is an oncoprotein with aberrant tyrosine kinase activity involved in the progression of chronic myeloid leukemia (CML) and has been targeted by inhibitors such as imatinib and nilotinib. However, despite their efficacy in the treatment of CML, a mechanism of resistance to these drugs associated with mutations in the kinase region has emerged. Therefore, in this work, we report the synthesis of 14 new 2,6,9-trisubstituted purines designed from our previous Bcr-Abl inhibitors. Here, we highlight 11b, which showed higher potency against Bcr-Abl (IC50 = 0.015 μM) than imatinib and nilotinib and exerted the most potent antiproliferative properties on three CML cells harboring the Bcr-Abl rearrangement (GI50 = 0.7-1.3 μM). In addition, these purines were able to inhibit the growth of KCL22 cell lines expressing Bcr-AblT315I, Bcr-AblE255K, and Bcr-AblY253H point mutants in micromolar concentrations. Imatinib and nilotinib were ineffective in inhibiting the growth of KCL22 cells expressing Bcr-AblT315I (GI50 > 20 μM) compared to 11b-f (GI50 = 6.4-11.5 μM). Molecular docking studies explained the structure-activity relationship of these purines in Bcr-AblWT and Bcr-AblT315I. Finally, cell cycle cytometry assays and immunodetection showed that 11b arrested the cells in G1 phase, and that 11b downregulated the protein levels downstream of Bcr-Abl in these cells.

Ponatinib-review of historical development, current status, and future research.

Ponatinib is a third-generation BCR::ABL1 tyrosine kinase inhibitor (TKI) with high potency against Philadelphia chromosome (Ph)-positive leukemias, including T315I-mutated disease, which is resistant to first- and second-generation TKIs. Ponatinib was approved for T315I-mutated chronic myeloid leukemia (CML), CML resistant/intolerant to ≥2 prior TKIs, advanced phase CML and Ph-positive acute lymphoblastic leukemia (ALL) where no other TKIs are indicated, and T315I-mutated CML and Ph-positive ALL. The response-based dosing of ponatinib in chronic phase CML (CP-CML) improved treatment tolerance and reduced the risk of toxicities, including cardiovascular risks. Ponatinib-based therapy also resulted in significantly better outcomes in frontline Ph-positive ALL compared with prior TKIs and is becoming a new standard of care in this setting. As the clinical development of third-generation TKIs and their rational combinations progresses, we envision further transformative changes in the treatment of CML and Ph-positive ALL.

Association between plasma imatinib levels and response to treatment of chronic myeloid leukemia in patients from Manaus, Brazil.

Imatinib mesylate (IM) is the drug of choice for the treatment of chronic myeloid leukemia (CML). However, despite most of the results obtained with this therapy being positive, some patients still present a suboptimal therapeutic response or still develop some type of resistance. Therefore, the aim of this study was to evaluate IM plasma levels in CML patients treated at a referral unit in Manaus and correlate them with variables that might interfere with these levels. Data from 52 patients were obtained through a standardized questionnaire containing clinical, sociodemographic, lifestyle, and use of other medication information, as well as an estimate of therapeutic adherence. Additionally, blood collection was performed to measure the plasma concentration of the drug using the HPLC-UV technique. Molecular studies were done to identify the presence of polymorphism in the ABCG2 C421A membrane transporter. Most patients were male with a mean age of 52 ± 12.3 years (95% CI 49.0-55.9). There was a high variation in drug concentrations in the range from 0 to 4694 ng/mL, with a mean of 1558.59 ± 989.79 ng/mL (95% CI 1283.0-1834.1). Approximately two-thirds of patients were classified in the drug-level range considered therapeutic, and there was a correlation between plasma concentration and higher molecular response. Additionally, most individuals had the normal genotype for the ABCG2 C421A polymorphism but further studies should be performed to reveal the role of this variable in the outcome of the disease in this population.

Allogeneic haematopoietic cell transplantation for chronic myeloid leukaemia in Switzerland in the face of rapid development of effective drugs.

Until the year 2000, allogeneic haematopoietic cell transplantation (HCT) was the standard treatment for young and fit chronic myeloid leukaemia (CML) patients. CML was the main indication for allogeneic HCT. The introduction of tyrosine kinase inhibitors changed the treatment of CML patients dramatically. Allogeneic HCT was rapidly replaced by tyrosine kinase inhibitors as first-line treatment for CML, and the indication shifted to the treatment of non-responders, patients intolerant to tyrosine kinase inhibitors and patients whose CML is transforming to the accelerated phase and blast crisis. This paper describes changes in the use of transplantation technology for CML patients in the face of rapid drug development. All patients receiving a transplant for CML between 1997 and 2021 in Switzerland were included in the study. For the purpose of this analysis, time periods were analysed in quinquennia, 1997-2001 (Q1), 2002-2006 (Q2), 2007-2011 (Q3), 2012-2016 (Q4) and 2017-2021 (Q5), as the observation period spanned 25 years. Overall, 239 patients received a transplant. These included 96 in Q1, 56 in Q2, 25 in Q3, 34 in Q4 and 28 in Q5. Patient characteristics changed over time: recent patients were older and had a longer interval from diagnosis to transplantation because of tyrosine kinase inhibitor treatment. However, the proportions of patients receiving transplants during an early versus advanced disease stage differed little. Transplant technology changed, as well. Patients received intensive conditioning regimens less often due to higher age and more commonly had peripheral blood as opposed to bone marrow transplants. However, the type of stem cell donor selected did not differ. In a univariable analysis, there were no significant differences in survival, progression-free survival, non-relapse mortality, relapse incidence or incidences of acute and chronic graft-versus-host disease among the five quinquennia. In a multivariable analysis, older age, donors other than HLA-identical siblings and more advanced disease stage, but not the quinquennium, were associated with higher risk of death. Since the introduction of tyrosine kinase inhibitors haematopoietic cell transplantation has been used less frequently to treat CML. Patients in recent cohorts received transplants at an older age and later in the disease course; despite these higher risks, the outcome of allogeneic HCT has not worsened over time but has not improved, either. As the outcome is worse in advanced phases, it is important to conduct transplants before disease progression. Therefore, patients with advanced disease should be monitored closely and receive transplants in time.

Myocardial Infarction in Chronic Myeloid Leukemia: Results from the Nationwide Readmission Database

Introduction: Chronic myeloid leukemia (CML) is a hematological malignancy with an excellent prognostic outcome. After the advancements in CML treatment and the introduction of different tyrosine kinase inhibitors (TKIs), the life expectancy of CML patients has become equivalent to that of the general population. As a result, coronary artery disease is anticipated to be the leading cause of death among CML patients. Moreover, TKI use is associated with a risk of endothelial dysfunction, thrombosis, and cardiovascular events, including myocardial infarction. In this study, we compare the outcomes of percutaneous coronary intervention (PCI) in patients with CML to their matched non-CML counterparts. Method: This is a retrospective cohort study using the Nationwide Readmission Database from January 2016 to December 2020. Adults with or without CML hospitalized for acute myocardial infarction and underwent PCI were included. The patients were identified using ICD-10 codes. The primary outcomes were in-hospital mortality and 30-day readmission rates. The secondary outcomes were PCI complications rates. Results: Out of 2,727,619 patients with myocardial infarction, 2,124 CML patients were identified. A total of 888 CML patients underwent PCI. CML patients were significantly older (mean age: 68.34 ± 11.14 vs. 64.40 ± 12.61 years, p < 0.001) than non-CML patients without a difference in sex distribution. Hypertension (85.45% vs. 78.64%), diabetes (45.48% vs. 37.29), stroke (11.84% vs. 7.78) at baseline were significantly higher in the CML group. Prior myocardial infarction events (20.51% vs. 15.17%) and prior PCI procedure (24.47% vs. 16.89%) were significantly higher in the CML group. CML patients had a significantly longer hospital stay (4.66 ± 4.40 vs. 3.75 ± 4.62 days, p = 0.001). The primary outcomes did not differ between the comparison groups. The risk of post-PCI complications did not differ between the comparison groups in the propensity matched analysis except for coronary artery dissection (odds ratio [OR]: 0.10; 95% confidence interval [CI]: 0.02–0.65, p = 0.016) and ischemic stroke (OR: 0.35; 95% CI: 0.14–0.93, p = 0.034) which were lower in the CML group. Conclusion: This analysis showed no statistically significant difference in mortality, 30-day readmission, and post PCI complications rates between CML and non-CML patients. However, interestingly, CML patients may experience lower coronary artery dissection and ischemic stroke events than those without CML diagnosis.

Treatment of chronic-phase chronic myeloid leukemia in patients randomized to dasatinib or imatinib after suboptimal responses to 3 months of imatinib therapy: final 5-year results from DASCERN.

Early molecular response at 3 months is predictive of improved overall survival and progression-free survival in patients with chronic myeloid leukemia in the chronic phase. Although about one-third of patients treated with first-line imatinib do not achieve an early molecular response, long-term overall survival and progression-free survival are still observed in most patients. DASCERN (NCT01593254) is a prospective, phase IIb, randomized trial evaluating a switch to dasatinib in patients who have not achieved an early molecular response after 3 months of treatment with first-line imatinib. Early analysis demonstrated an improved major molecular response (MMR) rate at 12 months with dasatinib versus imatinib (29% vs. 13%, P=0.005). Here, we report results from the final 5-year follow-up. In total, 174 patients were randomized to dasatinib and 86 to remain on imatinib. Forty-six (53%) patients who remained on imatinib but subsequently experienced failure were allowed to cross over to dasatinib per protocol. At a minimum follow-up of 60 months, the cumulative MMR rate was significantly higher in patients randomized to dasatinib than those randomized to imatinib (77% vs. 44%, P<0.001). The median time to MMR was 13.9 months with dasatinib versus 19.7 months with imatinib. The safety profile was consistent with previous reports. These results demonstrate that switching to dasatinib after a suboptimal response to imatinib at 3 months leads to faster MMR, provides earlier deep molecular responses, and improves some outcomes in patients with chronic myeloid leukemia in the chronic phase.

Efficacy and safety of flumatinib in the treatment of newly diagnosed chronic myeloid leukemia in the chronic phase: A real-world single-center retrospective study, with a focus on premature drug discontinuation

PurposeTo assess the real-world efficacy and safety of flumatinib as first-line and post-line treatments for chronic myeloid leukemia in the chronic phase (CML-CP). ResultsAmong 141 patients receiving flumatinib as first-line and post-line treatment, the 12-month major molecular response (MMR) rates were 69.4% and 67.6%, respectively. The median time to response was 6 and 10.5 months, respectively. In post-line treatment, the early molecular response (EMR) of flumatinib as second-line is significantly superior to that of third-line treatment (3-month EMR rate: 79.2% vs. 39.3%, P<0.001; 3-month MMR rate: 45.8% vs. 21.4%, P=0.033). Contrastively, patients who switched to flumatinib due to intolerance had significantly higher MMR rates at 3, 6, and 12 months compared to patients who switched due to inadequate response (60.6% vs. 24.2%, P=0.003; 66.7% vs. 36.0%, P=0.027; 84.2% vs. 50.0%, P=0.038). Premature drug discontinuation was observed in 28.4% of the patients. Grades 3–4 hematologic adverse events (AEs) were identified as independent risk factors for premature drug discontinuation. Patients who discontinued treatment and those who previously received only imatinib therapy had a poorer molecular response and failure-free survival. ConclusionsFlumatinib demonstrates favorable efficacy and safety. Treatment discontinuation can result in a poorer molecular response and long-term prognosis.

Proteomic Analysis Reveals Trilaciclib-Induced Senescence

Trilaciclib, a cyclin-dependent kinase 4/6 inhibitor, was approved as a myeloprotective agent for protecting bone marrow from chemotherapy-induced damage in extensive-stage small cell lung cancer. This is achieved through the induction of a temporary halt in the cell cycle of bone marrow cells. While it has been studied in various cancer types, its potential in hematological cancers remains unexplored. This research aimed to investigate the efficacy of trilaciclib in hematological cancers. Utilizing mass spectrometry-based proteomics, we examined the alterations induced by trilaciclib in the chronic myeloid leukemia cell line, K562. Interestingly, trilaciclib promoted senescence in these cells rather than cell death, as observed in acute myeloid leukemia, acute lymphoblastic leukemia, and myeloma cells. In K562 cells, trilaciclib hindered cell cycle progression and proliferation by stabilizing cyclin-dependent kinase 4/6 and downregulating cell cycle–related proteins, along with the concomitant activation of autophagy pathways. Additionally, trilaciclib-induced senescence was also observed in the nonsmall cell lung carcinoma cell line, A549. These findings highlight trilaciclib's potential as a therapeutic option for hematological cancers and underscore the need to carefully balance senescence induction and autophagy modulation in chronic myeloid leukemia treatment, as well as in nonsmall cell lung carcinoma cell line.

Integrated drug profiling and CRISPR screening identify BCR::ABL1-independent vulnerabilities in chronic myeloid leukemia

BCR::ABL1-independent pathways contribute to primary resistance to tyrosine kinase inhibitor (TKI) treatment in chronic myeloid leukemia (CML) and play a role in leukemic stem cell persistence. Here, we perform exvivodrug screening of CML CD34+ leukemic stem/progenitor cells using 100 single drugs and TKI-drugcombinations and identify sensitivities to Wee1, MDM2, and BCL2 inhibitors. These agents effectively inhibit primitive CD34+CD38- CML cells and demonstrate potent synergies when combined with TKIs. Flow-cytometry-baseddrug screening identifies mepacrine to induce differentiation of CD34+CD38- cells. We employ genome-wide CRISPR-Cas9 screening for six drugs, and mediator complex, apoptosis, and erythroid-lineage-related genes are identified as key resistance hits for TKIs, whereas the Wee1 inhibitor AZD1775 and mepacrine exhibit distinct resistance profiles. KCTD5, a consistent TKI-resistance-conferring gene, is found to mediate TKI-induced BCR::ABL1 ubiquitination. In summary, we delineate potential mechanismsfor primary TKI resistance and non-BCR::ABL1-targeting drugs, offering insights for optimizing CML treatment.

The Depth of the Molecular Response in Patients with Chronic Myeloid Leukemia Correlates with Changes in Humoral Immunity.

Background and Objectives: The effective treatment of chronic myeloid leukemia leads to the restoration of proper immune system function. We aimed to investigate fluctuations in circulating cytokines, angiogenic factors and complement components in patients with CML during the first year of treatment with TKI and correlate them with the degree of achieved molecular response. Material and Methods: We recruited 31 patients with newly diagnosed CML. Peripheral blood and bone marrow samples were obtained, and concentrations of serum proteins were measured using an immunology multiplex assay. Results: The study cohort was divided into two groups of optimal or non-optimal in accordance with the European Leukemia Net (ELN) guidelines. We found significantly higher concentrations of C1q, C4 and C5a in serum after 3 months of TKI treatment in patients who achieved optimal responses in the 6 months after diagnosis. The most alterations were observed during 12 months of therapy. Patients in the optimal response group were characterized by higher serum concentrations of TGF-β, EGF, VEGF, Angiopoietin 1, IFN-γ and IL-8. Conclusions: The later plasma concentrations of complement components were significantly increased in patients with optimal responses. The changes after 12 months of treatment were particularly significant. Similar changes in bone marrow samples were observed.

Discovery of a Meisoindigo-Derived PROTAC as the ATM Degrader: Revolutionizing Colorectal Cancer Therapy via Synthetic Lethality with ATR Inhibitors.

Meisoindigo (Mei) has long been recognized in chronic myeloid leukemia (CML) treatment. To elucidate its molecular target and mechanisms, we embarked on designing and synthesizing a series of Mei-derived PROTACs. Through this endeavor, VHL-type PROTAC 9b was identified to be highly cytotoxic against SW620, SW480, and K562 cells. Employing DiaPASEF-based quantitative proteomic analysis, in combination with extensive validation assays, we unveiled that 9b potently and selectively degraded ATM across SW620 and SW480 cells in a ubiquitin-proteasome-dependent manner. 9b-induced selective ATM degradation prompted DNA damage response cascades, thereby leading to the cell cycle arrest and cell apoptosis. This pioneering discovery renders the advent of ATM degradation for anti-cancer therapy. Notably, 9b-induced ATM degradation synergistically enhanced the efficacy of ATR inhibitor AZD6738 both in vitro and in vivo. This work establishes the synthetic lethality-inducing properties of ATR inhibitors in the ATM-deficient context, thereby providing new avenues to innovative therapies for colorectal cancer.