Impact of anemia on the outcomes of chronic phase chronic myeloid leukemia in TKI era

Small-molecule α-lipoic acid targets ELK1 to balance human neutrophil and erythrocyte differentiation

BACKGROUND

Erythroid and myeloid differentiation disorders are commonly occurred in leukemia. Given that the relationship between erythroid and myeloid lineages is still unclear. To find the co-regulators in erythroid and myeloid differentiation might help to find new target for therapy of myeloid leukemia. In hematopoiesis, ALA (alpha lipoic acid) is reported to inhibit neutrophil lineage determination by targeting transcription factor ELK1 in granulocyte-monocyte progenitors via splicing factor SF3B1. However, further exploration is needed to determine whether ELK1 is a common regulatory factor for erythroid and myeloid differentiation.

METHODS

In vitro culture of isolated CD34+, CMPs (common myeloid progenitors) and CD34+ CD371- HSPCs (hematopoietic stem progenitor cells) were performed to assay the differentiation potential of monocytes, neutrophils, and erythrocytes. Overexpression lentivirus of long isoform (L-ELK1) or the short isoform (S-ELK1) of ELK1 transduced CD34+ HSPCs were transplanted into NSG mice to assay the human lymphocyte and myeloid differentiation differences 3 months after transplantation. Knocking down of SRSF11, which was high expressed in CD371+GMPs (granulocyte-monocyte progenitors), upregulated by ALA and binding to ELK1-RNA splicing site, was performed to analyze the function in erythroid differentiation derived from CD34+ CD123mid CD38+ CD371- HPCs (hematopoietic progenitor cells). RNA sequencing of L-ELK1 and S-ELK1 overexpressed CD34+ CD123mid CD38+ CD371- HPCs were performed to assay the signals changed by ELK1.

RESULTS

Here, we presented new evidence that ALA promoted erythroid differentiation by targeting the transcription factor ELK1 in CD34+ CD371- hematopoietic stem progenitor cells (HSPCs). Overexpression of either the long isoform (L-ELK1) or the short isoform (S-ELK1) of ELK1 inhibited erythroid-cell differentiation, but knockdown of ELK1 did not affect erythroid-cell differentiation. RNAseq analysis of CD34+ CD123mid CD38+ CD371- HPCs showed that L-ELK1 upregulated the expression of genes related to neutrophil activity, phosphorylation, and hypoxia signals, while S-ELK1 mainly regulated hypoxia-related signals. However, most of the genes that were upregulated by L-ELK1 were only moderately upregulated by S-ELK1, which might be due to a lack of serum response factor interaction and regulation domains in S-ELK1 compared to L-ELK1. In summary, the differentiation of neutrophils and erythrocytes might need to rely on the dose of L-ELK1 and S-ELK1 to achieve precise regulation via RNA splicing signals at early lineage commitment.

CONCLUSIONS

ALA and ELK1 are found to regulate both human granulopoiesis and erythropoiesis via RNA spliceosome, and ALA-ELK1 signal might be the target of human leukemia therapy.

Clinical significance of prognostic nutritional index in myelodysplastic syndrome

BACKGROUND

Prognostic nutritional index has been found to be related to the clinical outcomes of patients with cancer. However, its role in myelodysplastic syndromes (MDS) patients is unclear. We aimed to assess the value of nutritional status in predicting the prognosis of MDS patients.

METHODS

Totally 121 MDS patients were analyzed retrospectively. The prognostic nutritional index (PNI) was used to assess nutritional status of the patients. The bio-informatics tool X-tile was used to define the threshold, and accordingly patients were divided into PNI^low and PNI^high groups, the characteristics were compared between two groups.

RESULTS

The PNI^high was associated with better OS (Overall Survival) than PNI^low in MDS patients (Median OS, 28.03 months versus 19.63 months, P = 0.0205). But there were no statistical differences in PFS (Progression-Free-Survival) between the two groups (P = 0.9373). The univariable and multivariable COX proportional hazard analysis adjusted for age, gender, platelet count, HB level and IPSS-R scores, and the results showed that PNI is a useful index in the evaluation of the OS of MDS (HR 0.588, 95%CI 0.374-0.926, P = 0.024).

CONCLUSION

PNI would be a simple and immediately available tool for predicting the prognosis of MDS.

Hematological Adverse Events with Tyrosine Kinase Inhibitors for Chronic Myeloid Leukemia: A Systematic Review with Meta-Analysis

Chronic myeloid leukemia (CML) is treated with tyrosine kinase inhibitors (TKI) that target the pathological BCR-ABL1 fusion oncogene. The objective of this statistical meta-analysis was to assess the prevalence of other hematological adverse events (AEs) that occur during or after predominantly first-line treatment with TKIs. Data from seventy peer-reviewed, published studies were included in the analysis. Hematological AEs were assessed as a function of TKI drug type (dasatinib, imatinib, bosutinib, nilotinib) and CML phase (chronic, accelerated, blast). AE prevalence aggregated across all severities and phases was significantly different between each TKI (p < 0.05) for anemia-dasatinib (54.5%), bosutinib (44.0%), imatinib (32.8%), nilotinib (11.2%); neutropenia-dasatinib (51.2%), imatinib (29.8%), bosutinib (14.1%), nilotinib (14.1%); thrombocytopenia-dasatinib (62.2%), imatinib (30.4%), bosutinib (35.3%), nilotinib (22.3%). AE prevalence aggregated across all severities and TKIs was significantly (p < 0.05) different between CML phases for anemia-chronic (28.4%), accelerated (66.9%), blast (55.8%); neutropenia-chronic (26.7%), accelerated (63.8%), blast (36.4%); thrombocytopenia-chronic (33.3%), accelerated (65.6%), blast (37.9%). An odds ratio (OR) with 95% confidence interval was used to compare hematological AE prevalence of each TKI compared to the most common first-line TKI therapy, imatinib. For anemia, dasatinib OR = 1.65, [1.51, 1.83]; bosutinib OR = 1.34, [1.16, 1.54]; nilotinib OR = 0.34, [0.30, 0.39]. For neutropenia, dasatinib OR = 1.72, [1.53, 1.92]; bosutinib OR = 0.47, [0.38, 0.58]; nilotinib OR = 0.47, [0.42, 0.54]. For thrombocytopenia, dasatinib OR = 2.04, [1.82, 2.30]; bosutinib OR = 1.16, [0.97, 1.39]; nilotinib OR = 0.73, [0.65, 0.82]. Nilotinib had the greatest fraction of severe (grade 3/4) hematological AEs (30%). In conclusion, the overall prevalence of hematological AEs by TKI type was: dasatinib > bosutinib > imatinib > nilotinib. Study limitations include inability to normalize for dosage and treatment duration.

Targeted Next-Generation Sequencing Identifies Additional Mutations Other than BCR∷ABL in Chronic Myeloid Leukemia Patients: A Chinese Monocentric Retrospective Study

A proportion of patients with somatic variants show resistance or intolerance to TKI therapy, indicating additional mutations other than BCR∷ABL1 may lead to TKI treatment failure or disease progression. We retrospectively evaluated 151 CML patients receiving TKI therapy and performed next-generation sequencing (NGS) analysis of 22 CML patients at diagnosis to explore the mutation spectrum other than BCR∷ABL1 affecting the achievement of molecular responses. The most frequently mutated gene was ASXL1 (40.9%). NOTCH3 and RELN mutations were only carried by subjects failing to achieve a major molecular response (MMR) at 12 months. The distribution frequency of ASXL1 mutations was higher in the group that did not achieve MR4.0 at 36 months (p = 0.023). The achievement of MR4.5 at 12 months was adversely impacted by the presence of >2 gene mutations (p = 0.024). In the analysis of clinical characteristics, hemoglobin concentration (HB) and MMR were independent factors for deep molecular response (DMR), and initial 2GTKI therapy was better than 1GTKI in the achievement of molecular response. For the scoring system, we found the ELTS score was the best for predicting the efficacy of TKI therapy and the Socal score was the best for predicting mutations other than BCR∷ABL.

Correlation of the transcription factors IRF4 and BACH2 with the abnormal NFATC1 expression in T cells from chronic myeloid leukemia patients

OBJECTIVE

T cell dysfunction is a common characteristic of patients with myeloid leukemia and is closely related to clinical efficacy and prognosis. In order to clarify the mechanisms leading to the T cell dysfunction, we characterized the gene expression profile of T cells from chronic myelogenous leukemia (CML) patients by microarray analysis and investigated the related regulating pathway.

METHODS

We employed gene expression profiling, bioinformatics and real-time quantitative reverse transcription PCR (RT-qPCR) to detect genes differentially expressed in CML patients versus healthy donors.

RESULTS

There were 1704 genes differentially expressed between CD3⁺ T cells from CML patients and healthy donors, including 868 up-regulated genes and 836 down-regulated genes, which mostly related to T cell functional pathways. In particular, lower expression of NFATC1, a member of the TCR signaling pathway, was detected in CD3⁺ T cells from CML patients. We further found that the expression of IRF4 and BACH2, transcription factors that potentially regulate NFATC1, in CD3⁺ T cells from CML patients was significantly lower than that in healthy donors.

CONCLUSION

We for the first time observed the altered gene expression profiles of CD3⁺ T cells from CML patients, and the results suggested that IRF4, BACH2 and NFATC1 may be involved in regulating T cell dysfunction in CML patients in the form of a transcriptional regulatory network. These findings may provide potential targets for tyrosine kinase inhibitors in combination with other targeted immunotherapies .

A predictive scoring system for therapy-failure in persons with chronic myeloid leukemia receiving initial imatinib therapy

Data from 1,364 consecutive subjects with chronic-phase chronic myeloid leukemia (CML) receiving initial imatinib-therapy were interrogated to identify co-variates predicting therapy failure. Subjects were randomly divided into training (n = 908) and validation datasets (n = 456). In the training dataset, WBC count ≥120 × 10E + 9/L, haemoglobin concentration <115 g/L, blood basophils ≥12% and European Treatment and Outcome Study for CML Long-Term Survival (ELTS) risk score were significantly-associated with failure-free survival (FFS). Each co-variate was assigned 1 point to develop the imatinib-therapy failure (IMTF) model except ELTS high-risk category which was assigned 2 points based on multi-variable regression coefficients. Area under receiver-operator characteristic curve values in the IMTF model for 1-, 3- and 5-year FFS were 0.79-0.84 in the training dataset and 0.78-0.85 in the validation dataset. Calibration plots showed high agreement between predicted and observed outcomes. Decision curve analyses indicated subjects benefited from clinical use of this model. Cumulative incidences of imatinib-therapy failure and probabilities of FFS among the 5 risk cohorts (very low-, low-, intermediate-, high- and very high-risk) using the IMTF model were significantly different (all p values < 0.001). The IMTF model also correlated with probabilities of progression-free survival and survival (all p values < 0.001). These data should help physicians optimize TKI-therapy strategy at diagnosis in persons with chronic phase CML.

[Combination of socio-demographic and clinical co-variates for predicting treatment responses and outcomes in patients with chronic myeloid leukemia in the chronic phase]

Objective: To explore the impacts of socio-demographic and clinical co-variates on treatment responses and outcomes in patients with chronic myeloid leukemia in the chronic phase (CML-CP) receiving tyrosine kinase inhibitor (TKI) and identified the predictive models for them. Methods: Data of newly diagnosed adult patients with CML-CP receiving first-line TKI and having complete socio-demographic data and clinical information were reviewed. Cox model was used to identify the independent variables associated with complete cytogenetic response (CCyR) , major molecular response (MMR) , molecular response 4 (MR(4)) and molecular response 4.5 (MR(4.5)) , as well as failure-free survival (FFS) , progression-free survival (PFS) , overall survival (OS) and CML-related OS. Results: A total of 1414 CML-CP patients treated with first-line imatinib (n=1176) , nilotinib (n=170) or dasatinib (n=68) were reviewed. Median age was 40 (18-83) years and 873 patients (61.7% ) were males. Result of the multivariate analysis showed that lower educational level (P<0.001-0.070) and EUTOS long-term survival intermediate or high-risk (P<0.001-0.009) were significantly associated with lower cumulative incidences of CCyR, MMR, MR(4) and MR(4.5), as well as the inferior FFS, PFS, OS and CML-related OS. In addition, those who were males, from rural households, had white blood cells (WBC) ≥120×10(9)/L, hemoglobin (HGB) <115 g/L and treated with first-line imatinib had significantly lower cumulative incidences of cytogenetic and/or molecular responses. Being single, divorced or widowed, having, rural household registration, WBC≥120×10(9)/L, HGB<15 g/L, and comorbidity (ies) was significantly associated with inferior FFS, PFS, OS, and/or CML-related OS. Thereafter, the patients were classified into several subgroups using the socio-demographic characteristics and clinical variables by cytogenetic and molecular responses, treatment failure and disease progression, as well as overall survival and CML-related OS, respectively. There were significant differences in treatment responses and outcomes among the subgroups (P<0.001) . Conclusion: Except for clinical co-variates, socio-demographic co-variates significantly correlated with TKI treatment responses and outcomes in CML-CP patients. Models established by the combination of independent socio-demographic and clinical co-variates could effectively predict the responses and outcome.

Prevalence of BCR-ABL T315I Mutation in Different Chronic Myeloid Leukemia patients Categories

&lt;b&gt;Background and Objective:&lt;/b&gt; Chronic Myelogenous Leukaemia (CML) is a clonal myeloproliferative tumor distinguished by the existence of the Philadelphia chromosome (Ph) resulting from the t (9, 22) (q34, q11) translocation. The BCR-ABL gene and the fusion protein, which has constitutive tyrosine kinase activity, are the outcome of this translocation. The purpose of this study is to determine the prevalence of the BCR-ABL T315I mutation in CML patients. &lt;b&gt;Materials and Methods:&lt;/b&gt; Descriptive cross-sectional studies were conducted on 100 CML patients who visited RICK hospital between May, 2018-2019. T315I mutation analysis was done on all patients utilizing (RT/PCR) followed by RLFP to quantify the prevalence of Kinase Domain Mutation analysis (KDM) in CML. &lt;b&gt;Results:&lt;/b&gt; The link between haematological parameters and ABL mutations in CML patients was shown to be a substantial positive correlation between T315I and haematological parameters (HB and WBC) but no correlation with PLT. The data revealed that 43 out of 99 CML had T315I, with highly prevalent gene express (43.4%) detected in all CML 56.6%. The correlation of T315I mutations with clinical status was positive significant (p-000). &lt;b&gt;Conclusion:&lt;/b&gt; It can be concluded that T315I mutation became significantly higher in CML patients than in other groups of mutations. The detection of ABL kinase domain mutations may be a proper and valuable strategy for optimizing therapeutic methods and preventing treatment delays.

Molecular response to imatinib in patients with chronic myeloid leukemia in Tanzania

Imatinib is the mainstay of treatment of patients with chronic myeloid leukemia (CML) in Tanzania. Monitoring molecular response to therapy by real-time polymerase chain reaction at defined milestones is necessary for early detection of treatment failure. However, this assay is not routinely performed in Tanzania; therefore, the depth of molecular response among patients with CML is not known. A total of 158 patients with previously diagnosed CML who received imatinib treatment were recruited from January 2019 and followed up through October 2020 at Ocean Road Cancer Institute. Information was obtained at the time of diagnosis and follow-up. Blood samples were collected in EDTA tubes to measure the BCR/ABL ratio on the Gene Xpert system for molecular response determination. The median age of the 158 adult patients was 45 years (range, 18-86). By reference to established treatment milestones, only 37 (23.4%) achieved optimal molecular response. Signs of advanced-stage disease, in particular the need for red cell transfusions before diagnosis (adjusted odds ratio [AOR], 3.4; 95% CI, 1.32-9.17) and cytopenias (AOR, 2.26; 95% CI, 1.03-4.96) necessitating drug interruptions were statistically validated predictors of treatment failure on multivariate, multinomial logistic regression. Patient survival at the 22-month follow-up was lowest, with 78.6% (95% CI, 69.4-85.4) in the failure-to-respond category and highest in patients achieving optimal response 97.0% (95% CI, 80.9-99.6). In summary, the majority of patients with CML treated with imatinib in Tanzania do not obtain deep molecular response. This outcome can be attributed to late diagnosis, the development of cytopenias requiring multiple drug interruptions, and poor adherence to treatment.

An aging mouse model of human chronic myeloid leukemia

Chronic myeloid leukemia (CML) is an age-dependent blood malignancy. Like many other age-dependent human diseases, laboratory animal research of CML uses young mice that do not factor in the influence of aging. To understand how aging may impact animal modeling of human age-dependent diseases, we established the first aging mouse model of human CML in BALB/c mice in the advanced age defined by 75% survival. This model was developed by noncytotoxic depletion of bone marrow lineage-positive cells followed by BCR-ABL retroviral transduction and transplantation. CML developed in aging mice shared many similarities to that in young mice, but had increased incidence of anemia that is often seen in human CML. Importantly, we showed that aging of both donor hematopoietic stem cells and recipient bone marrow niche impacted BCR-ABL mediated leukemogenesis and leukemia spectrum. Optimal CML induction relied on age-matching for donors and recipients, and cross-transplantation between young and old mice produced a mixture of different leukemia. Therefore, our model provides initial evidence of the feasibility and merit of CML modeling in aging mice and offers a new tool for future studies of CML stem cell drug resistance and therapeutic intervention in which aging would be taken into consideration as an influencing factor.