RATIONALE AND OBJECTIVES

The burden of acute myeloid leukemia (AML) is felt worldwide with increasing number of diagnosed cases. A recommended treatment option for a longer remission is hematopoietic stem cell transplantation after chemotherapy with cytarabine and an anthracycline antibiotic, either Idarubicin or Daunorubicin. In the Philippines, Doxorubicin, a cheaper and more accessible option for chemotherapy among those who have financial incapabilities. It is no longer part of the National Comprehensive Cancer Network (NCCN) recommendation for use however; it remains to be part of the Philippine National Clinical Practice Guideline in the treatment of AML. This leads us to wonder what the difference in outcome of patients who have received doxorubicin compared to those who received Idarubicin as induction chemotherapy.

This is a retrospective cohort study. Data was collected through chart review of AML patients admitted for induction chemotherapy. Descriptive statistics was used to analyze the sociodemographic and clinical profile of patients. Survival analysis was done using the Kaplan-Meier computation. The t-test for two proportions was used to compare outcomes between the two groups.

This study included 65 participants, 55 received idarubicin and 10 received doxorubicin. The average age of diagnosis in the Idarubicin group is 41.38 years, and 34.9 years in the Doxorubicin group. Majority of participants are females (58.18% vs 80%) and married (67.27% vs 60%). They are predominantly nonsmokers (89.09% vs 80%), with no maintenance medications (61.82% vs 70%), and comorbidities (70.91% vs 90%). There was no significant difference in the median overall survival of both groups (507 days vs 428 days, logrank test = 0.74).

Outcomes of this study leads us to conclude that Doxorubicin is not inferior to Idarubicin in terms of survival.

Chronic Myeloid Leukemia, a chronic hematopoietic stem cell disorder, is uncommon among younger age group such as pregnant patients. Due to the rarity of this condition in pregnancy, there are no randomized controlled trials to address the optimal management of this condition. We are presented with a 26 year old patient, who had an unplanned pregnancy in the advanced phase of the disease. Due to the risk to the mother in delaying treatment, she was continued on Imatinib, a tyrosine kinase inhibitor, which is a known fetal teratogen. Her pregnancy was carried to term. The patient delivered via spontaneous vaginal delivery to a live, neonate, with findings of hydrocele and syndactyly on the 4" and 5™ digit of the right foot. Due to the maternal disease progression, she presented with postpartum hemorrhage, in contrast to an augmented procoagulant state among normal pregnancies. Obstetric adjunctive measures, such as intrauterine balloon tamponade and uterine artery ligation, were done. The patient was discharged stable.
Leukemia, Myelogenous, Chronic, BCR-ABL Positive ; Imatinib Mesylate ; Postpartum Hemorrhage ; Pregnancy

The treatment of chronic myeloid leukemia (CML) was revolutionized with the advent of the first-generation tyrosine kinase inhibitors (TKIs), but drug resistance developed during treatment, leading to the development of the second-generation (dasatinib, nilotinib, and bosutinib) and third-generation (ponatinib) TKI. Compared with previous treatment regimens, specific TKI can significantly improve the response rate, overall survival rate and prognosis of CML. Only a few patients with BCR-ABL mutation are insensitive to the second-generation TKIs, so it is suggested to select the second-generation TKIs for patients with specific mutations. For patients with other mutations and without mutations, the second-generation TKI should be selected according to the patient's medical history, while the third-generation TKIs should be selected for mutations that are insensitive to the second-generation TKIs, such as T315I mutation that is sensitive to ponatinib. Due to different BCR-ABL mutations in patients with different sensitivity to the second and third-generation TKIs, this paper will review the latest research progress of the efficacy of the second and third-generation TKIs in CML patients with BCR-ABL mutations.
Humans ; Antineoplastic Agents/pharmacology* ; Dasatinib/pharmacology* ; Drug Resistance, Neoplasm/genetics* ; Fusion Proteins, bcr-abl/genetics* ; Leukemia, Myelogenous, Chronic, BCR-ABL Positive/drug therapy* ; Mutation ; Protein Kinase Inhibitors/therapeutic use*

OBJECTIVE: To investigate the expression and significance of regulatory T cells (Tregs), FoxP3 and transforming growth factor-β (TGF-β) in different phase of chronic myeloid leukemia (CML). METHODS: Peripheral blood of 73 CML patients in Department of Hematology, Heze Municipal Hospital from March 2018 to March 2021 were collected. According to patient's period in CML, they were divided into ND CML group (newly diagnosed), CP CML group (chronic period), and BP CML group (blast phase). The percentage of Tregs, expression level of FoxP3 mRNA and TGF-β were detected by flow cytometry, RT-qPCR, and ELISA, respecitively. The roles of above indices in clinical pathogenesis of patients with CML were analyzed. RESULTS: The proportion of Treg in the ND CML group was slightly higher than the CP CML group, but the difference was not statistically significant (P =0.695), while the BP CML group was significantly higher than the other two groups (P =0.008, P <0.001). The expression levels of FoxP3 mRNA in ND CML group, CP CML group and BP CML group were 11.61±2.21, 6.46±1.35 and 8.54±2.13, respectively. Significant difference in FoxP3 mRNA levels was observed among patients in different phases of CML (F =55.199, P <0.001). The expression levels of FoxP3 mRNA both in ND CML group and BP CML group were significantly higher than that in CP CML group (P <0.001), and the ND CML group was the highest (P <0.001). However, the expression levels of TGF-β in different phases of CML showed no statistical differences (H =0.634, P =0.728). CONCLUSION The abnormal distribution of Treg subset in different phases of CML and the significant increase of the expression level of FoxP3 mRNA in the new onset and blast phase of CML suggest that Tregs may promote the occurrence and progression of CML through immune regulation.
Humans ; Blast Crisis/metabolism* ; Forkhead Transcription Factors/metabolism* ; Leukemia, Myelogenous, Chronic, BCR-ABL Positive/genetics* ; RNA, Messenger/metabolism* ; T-Lymphocytes, Regulatory/metabolism* ; Transforming Growth Factor beta/metabolism*

Objective: To explore the influencing covariates of severe neutrophils and/or thrombocytopenia and their effect on treatment response and outcome in patients with chronic-phase chronic myeloid leukemia (CP-CML) receiving initial second-generation tyrosine kinase inhibitors (2G-TKI) . Methods: Data from consecutive patients aged ≥18 years with newly diagnosed CP-CML who received initial 2G-TKI at Peking University People's Hospital from September 2008 to November 2021 were interrogated. Binary logistic regression models and Fine-Gray and Cox regression models were applied. Results: Data from 267 patients who received initial 2G-TKI, including nilotinib (n=239, 89.5% ) and dasatinib (n=28, 10.5% ) , were interrogated. The median age was 36 (range, 18-73) years, and 156 (58.4% ) patients were male. At a median treatment period of 1.0 (0.1-3.0) month, 43 (16.1% ) patients developed grade ≥3 neutrophils and/or thrombocytopenia and recovered within 1.0 (0.1-24.6) month. Male (OR=2.9, 95% CI 1.2-6.8; P=0.018) , age of ≥36 years (OR=3.2, 95% CI 1.4-7.2, P=0.005) , a spleen below a costal margin of ≥7 cm (OR=2.8, 95% CI 1.2-6.6, P=0.020) , and a hemoglobin (HGB) level of <100 g/L (OR=2.9, 95% CI 1.3-6.8, P=0.012) at diagnosis were significantly associated with grade ≥ 3 neutrophils and/or thrombocytopenia. Based on their regression coefficients, male, age of ≥36 years, a spleen below a costal margin of ≥7 cm, and an HGB level of <100 g/L were given 1 point to form a predictive system. All patients were divided into three risk subgroups, and the incidence of severe cytopenia significantly differed among the three groups (P < 0.001) . Grade ≥3 neutrophils and/or thrombocytopenia for >2 weeks was significantly associated with lower cumulative incidences of complete cytogenetic response (CCyR, HR=0.5, 95% CI 0.3-0.7, P<0.001) and major molecular response (MMR, HR=0.4, 95% CI 0.3-0.8, P=0.004) and was not significantly associated with failure, progression, and survival. Conclusion: Male, advanced age, a large spleen, and a low HGB level were significantly associated with severe cytopenia. The four covariates were used to establish a prediction model, in which the incidence of severe cytopenia among different risk groups was significantly different. Severe cytopenia for >2 weeks was a negative factor for responses but not for outcomes.
Humans ; Male ; Adolescent ; Adult ; Female ; Protein Kinase Inhibitors/therapeutic use* ; Tyrosine Protein Kinase Inhibitors ; Treatment Outcome ; Retrospective Studies ; Dasatinib/therapeutic use* ; Leukemia, Myelogenous, Chronic, BCR-ABL Positive/drug therapy* ; Leukemia, Myeloid, Chronic-Phase/drug therapy* ; Thrombocytopenia

OBJECTIVE: To investigate the effect of Cyr61 on imatinib (IM) resistance in chronic myeloid leukemia (CML) and its mechanism. METHODS: Cyr61 level in cell culture supernatant was determined by enzyme-linked immunosorbent assay. The expression of Cyr61 and Bcl-xL were measured by real-time PCR and Western blot. Cell apoptosis was analyzed using an Annexin V-APC Kit. Expression of signal pathways related proteins was determined by Western blot. RESULTS: The level of Cyr61 obviously increased in K562G cells (IM resistance to CML cell line K562). Down-regulating the expression of Cyr61 decreased the resistance of K562G cells to IM and promoted IM induced apoptosis. In CML mouse model, down-regulating the expression of Cyr61 could increase the sensitivity of K562G cells to IM. The mechanism studies showed that Cyr61 mediated IM resistance in CML cells was related to the regulation of ERK1/2 pathways and apoptosis related molecule Bcl-xL by Cyr61. CONCLUSION Cyr61 plays an important role in promoting IM resistance of CML cells. Targeting Cyr61 or its related effectors pathways may be one of the ways to overcome IM resistance of CML cells.
Animals ; Humans ; Mice ; Apoptosis ; Drug Resistance, Neoplasm ; Imatinib Mesylate/pharmacology* ; K562 Cells ; Leukemia, Myelogenous, Chronic, BCR-ABL Positive/metabolism* ; Signal Transduction

OBJECTIVE: To explore the expression pattern and clinical significance of Integral membrane protein 2A（ITM2A） in drug resistant patients with chronic myeloid leukemia (CML). METHODS: The expression of ITM2A in CML was evaluated by qRT-PCR, Western blot and immunocytochemistry. In order to understand the possible biological effects of ITM2A, apoptosis, cell cycle and myeloid differentiation antigen expression of CML cells were detected by flow cytometry after over-expression of ITM2A. The nuderlying molecular mechanism of its biological effect was explored. RESULTS: The expression of ITM2A in bone marrow of CML resistant patients was significantly lower than that of sensitive patients and healthy donors（P<0.05）. The CML resistant strain cell K562R was successfully constructed in vitro. The expression of ITM2A in the resistant strain was significantly lower than that in the sensitive strain(P<0.05). Overexpression of ITM2A in K562R cells increased the sensitivity of K562R cells to imatinib and blocked the cell cycle in G₂ phase(P<0.05), but did not affect myeloid differentiation. Mechanistically, up-regulation of ITM2A reduced phosphorylation in ERK signaling (P<0.05). CONCLUSION The expression of ITM2A was low in patients with drug resistance of CML, and the low expression of ITM2A may be the key factor of imatinib resistance in CML.
Humans ; Antineoplastic Agents/pharmacology* ; Apoptosis ; Drug Resistance, Neoplasm ; Imatinib Mesylate/therapeutic use* ; K562 Cells ; Leukemia, Myelogenous, Chronic, BCR-ABL Positive/drug therapy* ; Signal Transduction

Objective: To develop a scoring system to predict molecular responses in patients with chronic myeloid leukemia in the chronic phase (CML-CP) receiving initial imatinib therapy. Methods: Data from consecutive adults with newly diagnosed CML-CP treated by initial imatinib was interrogated and subjects were distributed randomly into training and validation cohort, in a ratio of 2∶1. Fine-gray models were applied in the training cohort to identify co-variates of predictive value for major molecular response (MMR) and MR4. A predictive system was built using significant co-variates. The predictive system was then tested in the validation cohort and the area under the receiver-operator characteristic curve (AUROC) was used to estimate accuracy of the predictive system. Results: 1 364 CML-CP subjects receiving initial imatinib were included in this study. Subjects were distributed randomly into training cohort (n=909) and validation cohort (n=455) . In the training cohort, the male gender, European Treatment and Outcome Study for CML (EUTOS) Long-Term Survival (ELTS) intermediate-risk, ELTS high-risk, high WBC (≥130×10(9)/L or 120×10(9)/L, MMR or MR4) and low HGB (<110 g/L) at diagnosis were significantly related with poor molecular responses and were given points based on their regression coefficients. For MMR, male gender, ELTS intermediate-risk and low HGB (<110 g/L) were given 1 point; ELTS high-risk and high WBC (≥130×10(9)/L) , 2 points. For MR4, male gender was given 1 point; ELTS intermediate-risk and low HGB (<110 g/L) were given 2 points; high WBC (≥120×10(9)/L) , 3 points; ELTS high-risk, 4 points. We divided all subjects into 3 risk subgroups according to the predictive system above. Cumulative incidence of achieving MMR and MR4 in 3 risk subgroups was significantly different in both training and validation cohort (all P values <0.001) . In the training and validation cohorts, the time-dependent AUROC ranges of MMR and MR4 predictive systems were 0.70-0.84 and 0.64-0.81, respectively. Conclusions: A scoring system combining gender, WBC, HGB level and ELTS risk was built to predict MMR and MR4 in CML-CP patients receiving initial imatinib therapy. This system had good discrimination and accuracy, which could help phsicians optimize the selsction of initial TKI-therapy.
Adult ; Humans ; Male ; Imatinib Mesylate/therapeutic use* ; Antineoplastic Agents/therapeutic use* ; Treatment Outcome ; Protein Kinase Inhibitors/therapeutic use* ; Retrospective Studies ; Leukemia, Myelogenous, Chronic, BCR-ABL Positive/drug therapy* ; Chronic Disease

Humans ; Child ; Tyrosine Protein Kinase Inhibitors ; Leukemia, Myelogenous, Chronic, BCR-ABL Positive/drug therapy* ; Protein Kinase Inhibitors/therapeutic use* ; Chronic Disease

BACKGROUND: Imatinib mesylate (IM) resistance is an emerging problem for chronic myeloid leukemia (CML). Previous studies found that connexin 43 (Cx43) deficiency in the hematopoietic microenvironment (HM) protects minimal residual disease (MRD), but the mechanism remains unknown. METHODS: Immunohistochemistry assays were employed to compare the expression of Cx43 and hypoxia-inducible factor 1α (HIF-1α) in bone marrow (BM) biopsies of CML patients and healthy donors. A coculture system of K562 cells and several Cx43-modified bone marrow stromal cells (BMSCs) was established under IM treatment. Proliferation, cell cycle, apoptosis, and other indicators of K562 cells in different groups were detected to investigate the function and possible mechanism of Cx43. We assessed the Ca 2+ -related pathway by Western blotting. Tumor-bearing models were also established to validate the causal role of Cx43 in reversing IM resistance. RESULTS: Low levels of Cx43 in BMs were observed in CML patients, and Cx43 expression was negatively correlated with HIF-1α. We also observed that K562 cells cocultured with BMSCs transfected with adenovirus-short hairpin RNA of Cx43 (BMSCs-shCx43) had a lower apoptosis rate and that their cell cycle was blocked in G0/G1 phase, while the result was the opposite in the Cx43-overexpression setting. Cx43 mediates gap junction intercellular communication (GJIC) through direct contact, and Ca 2+ is the key factor mediating the downstream apoptotic pathway. In animal experiments, mice bearing K562, and BMSCs-Cx43 had the smallest tumor volume and spleen, which was consistent with the in vitro experiments. CONCLUSIONS Cx43 deficiency exists in CML patients, promoting the generation of MRD and inducing drug resistance. Enhancing Cx43 expression and GJIC function in the HM may be a novel strategy to reverse drug resistance and promote IM efficacy.
Animals ; Humans ; Mice ; Apoptosis ; Bone Marrow Cells ; Cell Communication ; Connexin 43/genetics* ; Gap Junctions/metabolism* ; Imatinib Mesylate/therapeutic use* ; K562 Cells ; Leukemia, Myelogenous, Chronic, BCR-ABL Positive/pathology* ; Mesenchymal Stem Cells/metabolism* ; Tumor Microenvironment ; Calcium/metabolism*