[Treatment status of tyrosine kinase inhibitor for newly-diagnosed chronic myeloid leukemia: a domestic multi-centre retrospective real-world study].

Objective: To retrospectively analyze the treatment status of tyrosine kinase inhibitors (TKI) in newly diagnosed patients with chronic myeloid leukemia (CML) in China. Methods: Data of chronic phase (CP) and accelerated phase (AP) CML patients diagnosed from January 2006 to December 2022 from 77 centers, ≥18 years old, and receiving initial imatinib, nilotinib, dasatinib or flumatinib-therapy within 6 months after diagnosis in China with complete data were retrospectively interrogated. The choice of initial TKI, current TKI medications, treatment switch and reasons, treatment responses and outcomes as well as the variables associated with them were analyzed. Results: 6 893 patients in CP (n=6 453, 93.6%) or AP (n=440, 6.4%) receiving initial imatinib (n=4 906, 71.2%), nilotinib (n=1 157, 16.8%), dasatinib (n=298, 4.3%) or flumatinib (n=532, 7.2%) -therapy. With the median follow-up of 43 (IQR 22-75) months, 1 581 (22.9%) patients switched TKI due to resistance (n=1 055, 15.3%), intolerance (n=248, 3.6%), pursuit of better efficacy (n=168, 2.4%), economic or other reasons (n=110, 1.6%). The frequency of switching TKI in AP patients was significantly-higher than that in CP patients (44.1% vs 21.5%, P<0.001), and more AP patients switched TKI due to resistance than CP patients (75.3% vs 66.1%, P=0.011). Multi-variable analyses showed that male, lower HGB concentration and ELTS intermediate/high-risk cohort were associated with lower cytogenetic and molecular responses rate and poor outcomes in CP patients; higher WBC count and initial the second-generation TKI treatment, the higher response rates; Ph(+) ACA at diagnosis, poor PFS. However, Sokal intermediate/high-risk cohort was only significantly-associated with lower CCyR and MMR rates and the poor PFS. Lower HGB concentration and larger spleen size were significantly-associated with the lower cytogenetic and molecular response rates in AP patients; initial the second-generation TKI treatment, the higher treatment response rates; lower PLT count, higher blasts and Ph(+) ACA, poorer TFS; Ph(+) ACA, poorer OS. Conclusion: At present, the vast majority of newly-diagnosed CML-CP or AP patients could benefit from TKI treatment in the long term with the good treatment responses and survival outcomes.

Frontline combination of dasatinib and low-intensity chemotherapy in adults with de novo Philadelphia chromosome-positive acute lymphoblastic leukemia.

BACKGROUND: Studies on dasatinib-based low-intensity induction regimens and post-remission strategies are limited in China. Therefore, we conducted a single-center phase 2 trial in newly diagnosed adult patients with Philadelphia chromosome-positive (Ph+) acute lymphoblastic leukemia (ALL) to establish the efficacy and safety of this treatment approach. RESEARCH DESIGN AND METHODS: Patients received one month of dasatinib plus low-intensity chemotherapy and two months of dasatinib monotherapy for induction, followed by a single course of high-dose methotrexate for consolidation. Subsequently, they underwent allogeneic hematopoietic stem cell transplantation (allo-HSCT) or tyrosine kinase inhibitor (TKI)-based treatment for maintenance therapy between October 2015 and August 2022. RESULTS: Twenty-two patients were enrolled. Median age was 45 years (range, 20-71). The rates of major and complete molecular responses in the third month were 18.2% and 40.9% respectively. With a median follow-up of 15 months (range, 5-89), the estimated 3-year disease-free survival (DFS) and overall survival (OS) were 52.4% and 73.2%, respectively. The TKI-based cohort had a significantly poorer DFS (p = 0.014) and OS (p = 0.008) than the allo-HSCT cohort. CONCLUSIONS: Our results suggest that dasatinib-based low-intensity chemotherapy is safe and effective as an induction strategy in the Chinese population. Allo-HSCT plays a crucial role in the long-term outcomes of patients with Ph+ ALL. CLINICAL TRIAL REGISTRATION: The trial was registered at ClinicalTrials.gov as NCT02690922.

[The Effect and Safety of Flumatinib in Patients with Chronic Myelogenous Leukemia Failed First-and Second-line Treatment].

OBJECTIVE: To analyze the efficacy and safety of flumatinib, a second-generation tyrosine kinase inhibitor (TKI) independently developed in China, in patients with chronic myelogenous leukemia in chronic phase (CML-CP) who falied first-line and second-line treatment. METHODS: The clinical data of 30 CML-CP patients treated with flumatinib in Lianyungang First People's Hospital from January 2020 to September 2022 were collected retrospectively. Among them, 15 patients who received imatinib first-line treatment but failed treatment were included in the second-line group, and the other 15 patients who failed second-line treatment with nilotinib or dasatinib were included in the third-line group. The hematological and molecular responses of the patients in the two groups at 3, 6 and 12 months of treatment, and the event-free survival (EFS) and adverse reactions of patients at the end of follow-up were statistical analyzed. RESULTS: At 3, 6, and 12 months of treatment, 10, 11, and 12 patients in the second line group achieved major molecular response (MMR), which was higher than that of 3, 4, and 5 patients in the third line group (P =0.010, P =0.011, P =0.010). At 3 months of treatment, 12 and 13 patients achieved complete hematological response (CHR) and early molecular response (EMR) in the second-line group, which was higher than that of 9 and 13 patients in the third-line group, but the difference between the two groups was not statistically significant (P =0.232, P =1.000); At 6 and 12 months of treatment, 6 and 7 patients in the second-line group achieved MR4.5, which were higher than of 3 and 2 cases in the third-line group, but the difference was not statistically significant (P =0.427, P =0.713). The hematological adverse reactions of patients in the second-line group during treatment the period were mainly grade 1-2 thrombocytopenia and anemia, and no grade 3-4 of adverse reactions occurred. In the third-line group, there were 2 cases of grade 1-2 thrombocytopenia, grade 1-2 anemia and white blood cell 3 cases were reduced each, 1 case of grade 3-4 anemia, 2 cases of grade 3-4 neutropenia. The non-hematological adverse reactions in the second-line group were rash (2 cases), headache (1 case), diarrhea (1 case), fatigue (1 case), limb pain (1 case). There were 1 cases of diarrhea, 1 cases of nausea, and 1 cases of edema in the third-line group. There was no statistical significance in hematological and non-hematological adverse reactions between the two groups of patients (P >0.05). At the end of follow-up, the EFS rate of patients in the second-line group was higher than that in the third-line group (100% vs 93.3%), but the difference was not statistically significant (P =0.317). CONCLUSION: The second-generation TKI flumatinib independently developed in China, has good curative effect and safety for CML-CP patients who failed first-line and second-line treatment.

[Discontinuation of tyrosine kinase inhibitors before epiphyseal closure leading to improved short stature in pediatric chronic myelogenous leukemia].

A 3-year-old boy was referred to our hospital with splenomegaly. Blood tests revealed hyperleukocytosis and bone marrow examination showed major BCR::ABL1 fusion, leading to the diagnosis of chronic myelogenous leukemia (CML). Due to intolerance, the tyrosine kinase inhibitor (TKI) was changed from imatinib to dasatinib to nilotinib. The patient achieved molecular remission but became markedly short in stature, measuring 129.3 cm (height standard deviation score [SDS] -3.3) at the age of 12. TKI therapy was discontinued at age 12 years and 10 months, which was 9 years and 8 months after the start of TKI and 1 year and 6 months after achievement of MR4.0, as discontinuation before epiphyseal closure would not improve short stature. At 2 years and 6 months after discontinuation, the patient's height improved to 156.1 cm (SDS-2.0) without relapse. Growth suppression by TKIs is a problem in the management of pediatric CML. This case illustrates how improvement in severe short stature can be achieved by discontinuing TKI therapy before epiphyseal closure.

Incidence of pleural effusion with dasatinib and the effect of switching therapy to a different TKI in patients with chronic phase CML.

Dasatinib is one of the second generation tyrosine kinase inhibitors (TKI) which is approved for the treatment of patients with chronic phase CML (CP-CML) both in the front line and in the second line setting. Pleural effusion (PE) is a unique toxicity associated with dasatinib use. Our aim was to study the incidence of pleural effusion in our cohort of patients who were treated with dasatinib for CP-CML and the safety upon TKI switch. A total of 390 patients were treated with dasatinib during their course of treatment for CP-CML. A total of 69 patients (17.6%) developed any grade of PE. About 33 (48%) patients developed CTCAE grade 2 PE, 34 (49%) grade 3 and only 1 patient developed grade 4 PE. Recurrence of PE was observed in 34 (49%) patients. While only 12 patients (17.3%) continued using dasatinib after development of PE, dasatinib was discontinued in the other 57 patients. Therapy was switched to bosutinib in 13 patients out of which 6 (46%) patients re-developed PE. While only 12.5% patients developed re-accumulation of pleural fluid in patients switched to imatinib, none of the patients switched to nilotinib re-developed PE. A change in TKI to bosutinib was associated with a 46% risk of recurrence of PE in patients who develop PE on dasatinib for the treatment of CP-CML. The incidence of recurrent PE was markedly lower in patient switched to imatinib or nilotinib.

[Ovarian hyperstimulation syndrome with controlled ovarian stimulation after induction therapy for Philadelphia chromosome-positive acute lymphoblastic leukemia].

A 27-year-old woman with newly diagnosed Philadelphia chromosome-positive acute lymphoblastic leukemia received induction therapy with dasatinib and prednisolone. From the time of diagnosis, oocyte storage was planned in accordance with the patient's wishes. After progesterone administration for suppression of menstruation, and blood cell recovery, ovarian stimulation was performed and a sufficient number of eggs was collected. The patient was considered at high risk for ovarian stimulation syndrome (OHSS) and received cabergoline and letrozole. However, ovarian enlargement and ascites were observed on ultrasonography 2 days after egg collection, and a diagnosis of moderate OHSS was made. Circulatory management was performed and low-molecular-weight heparin was administered. Dasatinib was discontinued due to the appearance of pleural effusion. Fluid retention improved after menstruation resumed, and the patient was able to continue consolidation with dasatinib and cord blood transplantation. Although tyrosine kinase inhibitors are expected to simplify planning of oocyte storage, the risk of complicating OHSS should be noted.

Synergistic effect of cannabidiol with dasatinib on lung cancer by SRC/PI3K/AKT signal pathway.

Dasatinib-related resistance frequently occurs and may lead to the failure of chemotherapy; thus, dose interruptions are necessary. Cannabidiol (CBD) has potential for integration with orthodox cancer care. In this study, we explored the combination effect of CBD and dasatinib on A549 cells. CBD in combination with dasatinib could induce significant synergistic apoptosis in vitro (ZIP > 10) and in vivo. The combination of CBD and low-dose dasatinib exhibited antiproliferative and proapoptotic effects through up-regulation of caspase-3 and Bax, and down-regulation of Bcl-2 in A549 cells. The xenograft mouse model suggested that the combination was more efficient and safer. In short, CBD and low-dose dasatinib exhibited a synergistic effect on anticancer by targeting the SRC/PI3K/AKT signaling pathway, suggesting a potential therapeutic option for the treatment of lung cancer.

YES1 as a potential target to overcome drug resistance in EGFR-deregulated non-small cell lung cancer.

Epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitors (TKIs) such as gefitinib and osimertinib have primarily been used as first-line treatments for patients with EGFR-activating mutations in non-small cell lung cancer (NSCLC). Novel biomarkers are required to distinguish patients with lung cancer who are resistant to EGFR-TKIs. The aim of the study is to investigate the expression and functional role of YES1, one of the Src-family kinases, in EGFR-TKI-resistant NSCLC. YES1 expression was elevated in gefitinib-resistant HCC827 (HCC827/GR) cells, harboring EGFR mutations. Moreover, HCC827/GR cells exhibited increased reactive oxygen species (ROS) levels compared to those of the parent cells, resulting in the phosphorylation/activation of YES1 due to oxidation of the cysteine residue. HCC827/GR cells showed elevated expression levels of YES1-associated protein 1 (YAP1), NF-E2-related factor 2 (Nrf2), cancer stemness-related markers, and antioxidant proteins compared to those of the parent cells. Knockdown of YES1 in HCC827/GR cells suppressed YAP1 phosphorylation, leading to the inhibition of Bcl-2, Bcl-xL, and Cyclin D1 expression. Silencing YES1 markedly attenuated the proliferation, migration, and tumorigenicity of HCC827/GR cells. Dasatinib inhibited the proliferation of HCC827/GR cells by targeting YES1-mediated signaling pathways. Furthermore, the combination of gefitinib and dasatinib demonstrated a synergistic effect in suppressing the proliferation of HCC827/GR cells. Notably, YES1- and Nrf2-regulated genes showed a positive regulatory relationship in patients with lung cancer and in TKI-resistant NSCLC cell lines. Taken together, these findings suggest that modulation of YES1 expression and activity may be an attractive therapeutic strategy for the treatment of drug-resistant NSCLC.

NK92 cells and peripheral blood NK cells respond oppositely upon dasatinib treatment.

Natural killer (NK) cell is a valuable tool for immunotherapy in cancer treatment, both the cultured cell line NK92 and primary NK cells are widely studied and used in research and clinical trials. Clinical observations witnessed the improvement of patients' NK cells in terms of cell counts and cytotoxic activity upon dasatinib treatment, an approved drug for chronic myeloid leukaemia and Ph+ acute lymphocytic leukaemia. Several studies supported the clinical observations, yet others argued a detrimental effect of dasatinib on NK cells. Due to the complex conditions in different studies, the definite influence of dasatinib on NK92 and primary NK cells remains to be settled. Here, we used a well-defined in vitro system to evaluate the effects of dasatinib on NK92 cells and peripheral blood (PB)-NK cells. By co-culturing NK cells with dasatinib to test the cell counts and target cell-killing activities, we surprisingly found that the chemical influenced oppositely on these two types of NK cells. While dasatinib suppressed NK92 cell proliferation and cytotoxic activity, it improved PB-NK-killing tumour cells. RNA sequencing analysis further supported this finding, uncovering several proliferating and cytotoxic pathways responding invertedly between them. Our results highlighted an intrinsic difference between NK92 and PB-NK cells and may build clues to understand how dasatinib interacts with NK cells in vivo.

Pharmacological Targeting of Senescence with Senolytics as a New Therapeutic Strategy for Neurodegeneration.

Cellular senescence is a state of permanent cell-cycle arrest. Early in life, senescence has a physiologic role in tumor suppression and wound healing. However, gradually, as these senescent cells accumulate over the lifespan of an organism, they contribute to inflammation and the progression of age-related diseases, including neurodegeneration. Targeting senescent cells using a class of drugs known as "senolytics" holds great promise for the management of Alzheimer's and Parkinson's disease. Already, several senolytic compounds have been shown to ameliorate cognitive deficits across several preclinical models of neurodegeneration. Most of these senolytics (e.g., dasatinib) are repurposed clinical or experimental anticancer drugs, which trigger apoptosis of senescent cells by interfering with pro-survival pathways. However, outside of their senolytic function, many first-generation senolytics also have other less appreciated neuroprotective effects, such as potent antioxidant and anti-inflammatory activity. In addition, some senolytic drugs may also have negative dose-limiting toxicities, including thrombocytopenia. In this review, we discuss the various biologic pathways targeted by the leading senolytic drugs, namely dasatinib, quercetin, fisetin, and navitoclax. We further evaluate the clinical transability of these compounds for neurodegeneration, assessing their adverse effects, pharmacokinetic properties, and chemical structure. SIGNIFICANCE STATEMENT: Currently, there are no effective disease-modifying treatments for the most prevalent neurodegenerative disorders, including Alzheimer's and Parkinson's disease. Some of the drugs currently available for treating these diseases are associated with unwanted side-effects and/or become less efficacious with time. Therefore, researchers have begun to explore new innovative treatments for these belligerent diseases, including senolytic drugs. These agents lead to the apoptosis of senescent cells thereby preventing their deleterious role in neurodegeneration.

Philadelphia Chromosome Positive and Philadelphia-Like Acute Lymphoblastic Leukemia in Children and Adolescents: Current Management, Controversies and Emerging Concepts.

Philadelphia chromosome positive (Ph+) acute lymphoblastic lymphoma (ALL) is an uncommon subtype of ALL in children, seen in 2-5% cases. Diagnostic evaluation includes conventional karyotyping and detection of BCR-ABL1 translocation by fluorescence in-situ hybridization (FISH) or reverse transcriptase polymerase chain reaction (RT-PCR). For children, the frontline management includes combination of intensive chemotherapy along with imatinib (300-340 mg/m2/d) or dasatinib (60-80 mg/m2/d). Imatinib/dasatinib should be introduced in induction as soon as results for BCR-ABL are available. Minimal residual disease (MRD) monitoring is essential; multi-parametric flowcytometry and immunoglobulin/T-cell receptor rearrangement PCR are the preferred methods. Intrathecal therapy with at least 12 doses of methotrexate is adequate for central nervous system (CNS) prophylaxis, but cranial radiation is necessary for CNS3 involvement. Allogeneic hematopoietic stem cell transplantation (HSCT) in first remission may be considered in high-risk cases (persistent MRD positivity/induction failure). Maintenance therapy with tyrosine kinase inhibitors (TKI) in children is debatable, with potential concerns for long term adverse effects. At relapse, the choice of TKI is guided by the presence of BCR-ABL tyrosine kinase domain resistance mutations, although the frequency of resistance mutations in children are lower. Allogeneic HSCT is essential for consolidation in second remission, if not done. Ph-like ALL is a newly recognized molecular entity, with gene expression profile similar to Ph+ALL and poor survival outcomes. In resource-constrained settings, a stepwise cost-effective diagnostic evaluation should be considered among high-risk patients without recurrent genetic abnormalities. Current treatment strategies remain similar to Ph-negative ALL. Enrolment in clinical trials is encouraged for such children to evaluate potential targeted agents in this subtype.

Human Rotator Cuff Tears Reveal an Age-Dependent Increase in Markers of Cellular Senescence and Selective Removal of Senescent Cells With Dasatinib + Quercetin Increases Genetic Expression of COL1A1 In Vitro.

PURPOSE: To quantify cellular senescence in supraspinatus tendon and subacromial bursa of humans with rotator cuff tears and to investigate the in vitro efficacy of the senolytic dasatinib + quercetin (D+Q) to eliminate senescent cells and alter tenogenic differentiation. METHODS: Tissue was harvested from 41 patients (mean age, 62 years) undergoing arthroscopic rotator cuff repairs. In part 1 (n = 35), senescence was quantified using immunohistochemistry and gene expression for senescent cell markers (p16 and p21) and the senescence-associated secretory phenotype (SASP) (interleukin [IL] 6, IL-8, matrix metalloproteinase [MMP] 3, monocyte chemoattractant protein [MCP] 1). Senescence was compared between patients <60 and ≥60 years old. In part 2 (n = 6) , an in vitro model of rotator cuff tears was treated with D+Q or control. D+Q, a chemotherapeutic and plant flavanol, respectively, kill senescent cells. Gene expression analysis assessed the ability of D+Q to kill senescent cells and alter markers of tenogenic differentiation. RESULTS: Part 1 revealed an age-dependent significant increase in the relative expression of p21, IL-6, and IL-8 in tendon and p21, p16, IL-6, IL-8, and MMP-3 in bursa (P < .05). A significant increase was seen in immunohistochemical staining of bursa p21 (P = .028). In part 2, D+Q significantly decreased expression of p21, IL-6, and IL-8 in tendon and p21 and IL-8 in bursa (P < .05). Enzyme-linked immunosorbent assay analysis showed decreased release of the SASP (IL-6, MMP-3, MCP-1; P = .002, P = .024, P < .001, respectively). Tendon (P = .022) and bursa (P = .027) treated with D+Q increased the expression of COL1A1. CONCLUSIONS: While there was an age-dependent increase in markers of cellular senescence, this relationship was not consistently seen across all markers and tissues. Dasatinib + quercetin had moderate efficacy in decreasing senescence in these tissues and increasing COL1A1 expression. CLINICAL RELEVANCE: This study reveals that cellular senescence may be a therapeutic target to alter the biological aging of rotator cuffs and identifies D+Q as a potential therapy.

Real-World Effectiveness of Dasatinib Versus Imatinib in Newly Diagnosed Patients With Chronic Myeloid Leukemia.

INTRODUCTION: Limited data exist comparing dasatinib with imatinib in clinical practice. This study assessed real-world outcomes associated with first-line (1L) dasatinib or imatinib treatment of chronic myeloid leukemia (CML). PATIENTS AND METHODS: This retrospective, observational, United States multisite cohort study analyzed electronic medical record data from adults with Philadelphia chromosome-positive (Ph+) CML in the chronic phase (CML-CP) after 1L dasatinib or imatinib between January 2014 and September 2018. Rates of and times to major molecular response (MMR) and deep molecular response (DMR) were assessed overall and in subgroups (low vs. intermediate/high risk, aged <65 vs. ≥65 years, low/normal vs. high body mass index [BMI]). RESULTS: The dasatinib cohort (n = 309) experienced higher rates of MMR (n = 304, 79% vs. 65%, P < .001) and DMR (44% vs. 25%, P < .001) vs. the imatinib cohort with shorter median times to MMR (11.9 vs. 14.7 months, P < .001) and DMR (30.3 vs. 66.1 months, P < .001). Patients with intermediate-/high-risk disease and those aged <65 years had higher MMR and DMR rates and achieved response earlier with dasatinib (P < .01). Patients with low-risk disease treated with dasatinib had higher rates of DMR (60% vs. 32%, P = .01). Across BMI strata, rates of MMR and DMR were higher with dasatinib (P < .05). CONCLUSIONS: Patients with CML-CP treated with 1L dasatinib achieved higher rates of, with shorter times to, MMR and DMR versus 1L imatinib. These clinically meaningful improvements were observed across subgroups.

A Case Report of Infant-Type Hemispheric Glioma with a Novel GAB1-ABL2 Kinase Fusion Treated with Dasatinib.

INTRODUCTION: Infant-type hemispheric glioma (IHG) is a rare form of cancer that affects newborns and infants. It is classified as a pediatric-type high-grade glioma and typically harbors receptor tyrosine kinase (RTK) gene fusions. Here, we present the finding of a novel gene fusion IHG treated with a targeted therapy that has yet to be implemented for any other IHG case to date. CASE PRESENTATION: We report the case of a 12-month-old boy with IHG who presented with obstructive hydrocephalus due to a large mass in the right frontal lobe. The patient initially underwent mass resection, but subsequent imaging showed rapid interval progression of the residual tumor. Comprehensive molecular analysis of the tumor tissue revealed a novel GAB1-ABL2 gene fusion, and the patient was started on dasatinib, an ABL kinase inhibitor. Shortly after initiation of dasatinib treatment, there was a significant reduction in tumor size and enhancement, followed by stabilization of disease. DISCUSSION: The patient's robust response to treatment suggests that dasatinib is an effective targeted therapy for IHG harboring a GAB1-ABL2 gene fusion. This finding may inform future investigations into the disease processes of IHG and help guide the diagnosis and treatment of IHG in the absence of previously identified gene fusions, improving clinical management of this vulnerable patient population.

Editorial Commentary: Dasatinib With Quercetin Shows Promise in Decreasing Age-Related Senescence in the Rotator Cuff Tendon-Can It Work Elsewhere?

Cellular senescence is a fundamental mechanism seen in all age-related diseases. Human supraspinatus tendon and adjacent bursal specimens evaluated for cellular senescence by immunohistochemistry and gene expression show more senescent cells in older patients. This confirms the observation that older patients are more likely to have rotator cuff pathology, and older age is associated with lower rates of rotator cuff healing and more frequent tendon retears. Senolytic drugs can selectively eliminate senescent cells without a localized or systemic impact. Tendon and bursal specimens co-cultured and then incubated with dasatinib and quercetin for 48 hours show a significant decrease in senescent cells. This suggests that these drugs may slow biological aging in rotator cuff tendons and offer the possibility of a clinically effective treatment for the aging rotator cuff tendon. Moreover, this concept is promising for the development of future effective therapies addressing tissue senescence.

[Sustaining molecular response with very low dose ponatinib and further response after hemodialysis initiation in a patient with chronic myeloid leukemia].

A 46-year-old man was diagnosed with chronic myeloid leukemia (CML) in chronic phase. He was treated with imatinib, nilotinib, and dasatinib, but failed to achieve a complete cytogenetic response (CCyR). After tyrosine kinase inhibitor therapy, F317L BCR-ABL1 kinase domain mutation was detected. At age 66, the patient started ponatinib (PON) at 45 mg/day, and achieved CCyR within three months. Subsequently, PON was tapered to 15 mg once weekly due to arterial-occlusive events. PON was discontinued after a 3-year deep molecular response (≥ MR4.5). However, the patient lost MR4.0 within two months, and PON (15 mg once weekly) was restarted. He achieved MR4.0 again within one month, and then a deeper molecular response (MR5.0) after starting dialysis therapy at the same PON dose. The trough value of PON (15 mg once weekly) was 5.8 ng/ml, which suppressed F317L mutation in the CML clone. Currently, the patient is 77 years old and is sustaining MR5.0. Chronic renal failure may cause hyperabsorption and metabolic retardation in patients receiving PON. Initiation of hemodialysis may improve homeostasis resulting in enhanced anti-tumor immunity against CML.

Comparison of cutaneous adverse events between second-generation tyrosine kinase inhibitors and imatinib for chronic myeloid leukemia: a systematic review and meta-analysis.

BACKGROUND: Patients with chronic myeloid leukemia (CML) treated with tyrosine kinase inhibitors (TKIs) often experience cutaneous adverse events, such as rashes and pruritus. In this study, we aimed to compare the risks of cutaneous adverse events between imatinib- and second-generation TKI-treated patients with CML. MATERIAL AND METHODS: Paired reviewers independently obtained studies from PubMed, Embase, and Cochrane Library published until 15 March 2022. The following terms were searched: (Leukemia, Myelogenous, Chronic and BCR-ABL Positive), chronic myeloid leukemia, tyrosine kinase inhibitor, TKI, imatinib, dasatinib, nilotinib, bosutinib, and radotinib. Two independent reviewers screened the results and selected articles on cutaneous adverse events. RevMan 5.4 and the Cochrane Collaboration tool were used to perform the meta-analysis and risk of bias assessment. RESULTS AND CONCLUSION: Eleven trials involving 4502 patients were analyzed in this study. Patients treated with second-generation TKIs were significantly more likely to experience cutaneous adverse events than those treated with imatinib with a relative risk (RR) of 1.62 (95% confidence interval [CI], [1.25-2.09]). Except dasatinib (RR [95% CI], 1.39 [0.75-2.56]), the risk of adverse events was more with second-generation TKIs than with imatinib as follows: nilotinib (2.11 [1.53-2.90]), bosutinib (1.41 [1.07-1.86]), and radotinib (1.87 [1.33-2.63]). Rash was the most common cutaneous adverse event that was observed in 21.6% of cases across all grades, followed by pruritus (5.7%) and alopecia (4.3%). In conclusion, our findings suggest that cutaneous adverse events occur more frequently with second-generation TKIs than with imatinib. Therefore, effective management of the cutaneous outcome is necessary to achieve high patient adherence to medication and successful treatment with TKIs.

PD-1 blockade in combination with dasatinib potentiates induction of anti-acute lymphocytic leukemia immunity.

Immunotherapy, in the form of hematopoietic stem cell transplantation (HSCT), has been part of the standard of care in the treatment of acute leukemia for over 40 years. Trials evaluating novel immunotherapeutic approaches, such as targeting the programmed death-1 (PD-1) pathway, have unfortunately not yielded comparable results to those seen in solid tumors. Major histocompatibility complex (MHC) proteins are cell surface proteins essential for the adaptive immune system to recognize self versus non-self. MHC typing is used to determine donor compatibility when evaluating patients for HSCT. Recently, loss of MHC class II (MHC II) was shown to be a mechanism of immune escape in patients with acute myeloid leukemia after HSCT. Here we report that treatment with the tyrosine kinase inhibitor, dasatinib, and an anti-PD-1 antibody in preclinical models of Philadelphia chromosome positive B-cell acute lymphoblastic leukemia is highly active. The dasatinib and anti-PD-1 combination reduces tumor burden, is efficacious, and extends survival. Mechanistically, we found that treatment with dasatinib significantly increased MHC II expression on the surface of antigen-presenting cells (APC) in a tumor microenvironment-independent fashion and caused influx of APC cells into the leukemic bone marrow. Finally, the induction of MHC II may potentiate immune memory by impairing leukemic engraftment in mice previously cured with dasatinib, after re-inoculation of leukemia cells. In summary, our data suggests that anti-PD-1 therapy may enhance the killing ability of dasatinib via dasatinib driven APC growth and expansion and upregulation of MHC II expression, leading to antileukemic immune rewiring.