Browsing by Author "Kostic, Tatjana (57190702347)"

Acute lymphoblastic leukemia (ALL) is the most common cancer in children, whereas it is less common in adults. Identification of cytogenetic aberrations and a small number of molecular abnormalities are still the most important risk and therapy stratification methods in clinical practice today. Next generation sequencing (NGS) technology provides a large amount of data contributing to elucidation of mutational landscape of childhood (cALL) and adult ALL (aALL). We analyzed DNA samples from 34 cALL and aALL patients, using NGS targeted sequencing TruSeq Amplicon - Cancer Panel (TSACP) which targets mutational hotspots in 48 cancer related genes. We identified a total of 330 variants in the coding regions, out of which only 95 were potentially protein-changing. Observed in individual patients, detected mutations predominantly disrupted Ras/RTK pathway (STK11, KIT, MET, NRAS, KRAS, PTEN). Additionally, we identified 5 patients with the same mutation in HNF1A gene, disrupting both Wnt and Notch signaling pathway. In two patients we detected variants in NOTCH1 gene. HNF1A and NOTCH1 variants were mutually exclusive, while genes involved in Ras/RTK pathway exhibit a tendency of mutation accumulation. Our results showed that ALL contains low number of mutations, without significant differences between cALL and aALL (median per patient 2 and 3, respectively). Detected mutations affect few key signaling pathways, primarily Ras/RTK cascade. This study contributes to knowledge of ALL mutational landscape, leading to better understanding of molecular basis of this disease. © 2019 Dragana Janic, Jelena Peric, Teodora Karan-Djurasevic, Tatjana Kostic, Irena Marjanovic, Bojana Stanic, Nadja Pejanovic, Lidija Dokmanovic, Jelena Lazic, Nada Krstovski, Marijana Virijevic, Dragica Tomin, Ana Vidovic, Nada Suvajdzic Vukovic, Sonja Pavlovic, Natasa Tosic, published by Sciendo.

Acute lymphoblastic leukemia (ALL) is the most common cancer in children, whereas it is less common in adults. Identification of cytogenetic aberrations and a small number of molecular abnormalities are still the most important risk and therapy stratification methods in clinical practice today. Next generation sequencing (NGS) technology provides a large amount of data contributing to elucidation of mutational landscape of childhood (cALL) and adult ALL (aALL). We analyzed DNA samples from 34 cALL and aALL patients, using NGS targeted sequencing TruSeq Amplicon - Cancer Panel (TSACP) which targets mutational hotspots in 48 cancer related genes. We identified a total of 330 variants in the coding regions, out of which only 95 were potentially protein-changing. Observed in individual patients, detected mutations predominantly disrupted Ras/RTK pathway (STK11, KIT, MET, NRAS, KRAS, PTEN). Additionally, we identified 5 patients with the same mutation in HNF1A gene, disrupting both Wnt and Notch signaling pathway. In two patients we detected variants in NOTCH1 gene. HNF1A and NOTCH1 variants were mutually exclusive, while genes involved in Ras/RTK pathway exhibit a tendency of mutation accumulation. Our results showed that ALL contains low number of mutations, without significant differences between cALL and aALL (median per patient 2 and 3, respectively). Detected mutations affect few key signaling pathways, primarily Ras/RTK cascade. This study contributes to knowledge of ALL mutational landscape, leading to better understanding of molecular basis of this disease. © 2019 Dragana Janic, Jelena Peric, Teodora Karan-Djurasevic, Tatjana Kostic, Irena Marjanovic, Bojana Stanic, Nadja Pejanovic, Lidija Dokmanovic, Jelena Lazic, Nada Krstovski, Marijana Virijevic, Dragica Tomin, Ana Vidovic, Nada Suvajdzic Vukovic, Sonja Pavlovic, Natasa Tosic, published by Sciendo.

Background: In chronic lymphocytic leukemia (CLL), in vivo apoptotic resistance of malignant B lymphocytes results, in part, from the intrinsic defects of their apoptotic machinery. These include genetic alterations and aberrant expression of many apoptosis regulators, among which the Bcl2 family members play a central role. Aim: The aim of this study was to investigate the association of pro-apoptotic Bax gene expression and Bcl2/Bax ratio with the clinical features of CLL patients as well as with molecular prognostic markers, namely the mutational status of rearranged immunoglobulin heavy variable (IGHV) genes and lipoprotein lipase (LPL) gene expression. Methods: We analyzed the expression of Bax mRNA and Bcl2/Bax mRNA ratio in the peripheral blood mononuclear cells of 58 unselected CLL patients and 10 healthy controls by the quantitative reverse-transcriptase polymerase chain reaction. Results: We detected significant Bax gene overexpression in CLL samples compared to non-leukemic samples (p=0.003), as well as an elevated Bcl2/Bax ratio (p=<0.001). Regarding the association with prognostic markers, the Bcl2/Bax ratio showed a negative correlation to lymphocyte doubling time (r=-0.307; p=0.0451), while high-level Bax expression was associated with LPL-positive status (p=0.035). Both the expression of Bax and Bcl2/Bax ratio were higher in patients with unmutated vs. mutated IGHV rearrangements, but this difference did not reach statistical significance. Conclusions: Our results suggest that dysregulated expression of Bcl2 and Bax, which leads to a high Bcl2/Bax ratio in leukemic cells, contributes to the pathogenesis and clinical course of CLL.

Background: In chronic lymphocytic leukemia (CLL), in vivo apoptotic resistance of malignant B lymphocytes results, in part, from the intrinsic defects of their apoptotic machinery. These include genetic alterations and aberrant expression of many apoptosis regulators, among which the Bcl2 family members play a central role. Aim: The aim of this study was to investigate the association of pro-apoptotic Bax gene expression and Bcl2/Bax ratio with the clinical features of CLL patients as well as with molecular prognostic markers, namely the mutational status of rearranged immunoglobulin heavy variable (IGHV) genes and lipoprotein lipase (LPL) gene expression. Methods: We analyzed the expression of Bax mRNA and Bcl2/Bax mRNA ratio in the peripheral blood mononuclear cells of 58 unselected CLL patients and 10 healthy controls by the quantitative reverse-transcriptase polymerase chain reaction. Results: We detected significant Bax gene overexpression in CLL samples compared to non-leukemic samples (p=0.003), as well as an elevated Bcl2/Bax ratio (p=<0.001). Regarding the association with prognostic markers, the Bcl2/Bax ratio showed a negative correlation to lymphocyte doubling time (r=-0.307; p=0.0451), while high-level Bax expression was associated with LPL-positive status (p=0.035). Both the expression of Bax and Bcl2/Bax ratio were higher in patients with unmutated vs. mutated IGHV rearrangements, but this difference did not reach statistical significance. Conclusions: Our results suggest that dysregulated expression of Bcl2 and Bax, which leads to a high Bcl2/Bax ratio in leukemic cells, contributes to the pathogenesis and clinical course of CLL.

Fludarabine plus cyclophosphamide (FC) chemotherapy is the basis of treatment protocols used in management of chronic lymphocytic leukemia (CLL). In some patients, response to therapy may be affected by aberrant function of genes involved in pharmacokinetics and pharmacodynamics of the drugs. The aim of this research was to assess the impact of pharmacogenetic variability, namely expression of SLC28A3 gene and the presence of CYP2B6*6 variant allele, on the FC treatment efficacy. Forty-four CLL patients with functional TP53 gene at the time of FC initiation were enrolled in this study. CYP2B6 genotyping was performed by polymerase chain reaction and direct sequencing. SLC28A3 expression was measured by quantitative reverse-transcriptase polymerase chain reaction. Significantly higher pretreatment levels of SLC28A3 mRNA were detected in patients who failed to respond to FC in comparison to patients who achieved complete and partial response (p = 0.01). SLC28A3 high-expressing cases were almost ten times more likely not to respond to FC than low-expressing cases (OR = 9.8; p = 0.046). However, association of SLC28A3 expression with progression-free survival (PFS) and overall survival (OS) was not observed. CYP2B6*6 allele, detected in 24 patients (54.6%), exerted no association with the attainment of response to FC, as well as with PFS and OS. The results of this study demonstrate that SLC28A3 expression is a significant predictor of FC efficacy in CLL patients with intact TP53. Elevated SLC28A3 mRNA levels are associated with inferior short-term response to FC, suggesting that, if validated on larger cohorts, SLC28A3 expression may become a biomarker useful for pretreatment stratification of patients. © 2019, Arányi Lajos Foundation.

Fludarabine plus cyclophosphamide (FC) chemotherapy is the basis of treatment protocols used in management of chronic lymphocytic leukemia (CLL). In some patients, response to therapy may be affected by aberrant function of genes involved in pharmacokinetics and pharmacodynamics of the drugs. The aim of this research was to assess the impact of pharmacogenetic variability, namely expression of SLC28A3 gene and the presence of CYP2B6*6 variant allele, on the FC treatment efficacy. Forty-four CLL patients with functional TP53 gene at the time of FC initiation were enrolled in this study. CYP2B6 genotyping was performed by polymerase chain reaction and direct sequencing. SLC28A3 expression was measured by quantitative reverse-transcriptase polymerase chain reaction. Significantly higher pretreatment levels of SLC28A3 mRNA were detected in patients who failed to respond to FC in comparison to patients who achieved complete and partial response (p = 0.01). SLC28A3 high-expressing cases were almost ten times more likely not to respond to FC than low-expressing cases (OR = 9.8; p = 0.046). However, association of SLC28A3 expression with progression-free survival (PFS) and overall survival (OS) was not observed. CYP2B6*6 allele, detected in 24 patients (54.6%), exerted no association with the attainment of response to FC, as well as with PFS and OS. The results of this study demonstrate that SLC28A3 expression is a significant predictor of FC efficacy in CLL patients with intact TP53. Elevated SLC28A3 mRNA levels are associated with inferior short-term response to FC, suggesting that, if validated on larger cohorts, SLC28A3 expression may become a biomarker useful for pretreatment stratification of patients. © 2019, Arányi Lajos Foundation.

Introduction: The B-cell lymphoma/leukaemia 11A (BCL11A) gene encodes a Krüppel-like transcription factor involved in lymphocyte development during normal haematopoiesis. Aberrant expression of BCL11A has been observed in several haematological malignancies, including chronic lymphocytic leukaemia (CLL). However, its functions in the regulatory networks of malignant B lymphocytes are poorly understood, as are the relations to clinical course and outcome of B-cell malignancies, particularly CLL. Methods: The expression of BCL11A was analysed in peripheral blood mononuclear cells of 87 newly-diagnosed CLL patients by quantitative reverse-transcriptase polymerase chain reaction (qRT-PCR), and association with clinical and molecular variables was assessed. Results: BCL11A was significantly overexpressed in CLL samples compared to control samples (p < 0.001). BCL11A expression level exhibited no association with age, sex, leukocyte, lymphocyte and platelet counts, haemoglobin level, serum β2-microglobulin, CD38 status and cytogenetic abnormalities. On the other hand, high BCL11A expression was associated with low serum lactate dehydrogenase (p = 0.031), Binet A stage (p = 0.047) and mutated IGHV (p = 0.028). In addition, a positive correlation with BCL2/BAX mRNA ratio was observed (r = 0.36; p < 0.001). Regarding the association with the time to first treatment (TTFT), a trend towards longer median TTFT in BCL11A high- versus BCL11A low-expressing cases was detected (21 vs. 6 months; p = 0.164). Conclusion: The results of this study show that BCL11A is upregulated in CLL patients, and that high BCL11A expression at diagnosis may be associated with better prognosis. These data are consistent with the role of BCL11A expression in CLL biology, and imply its potential prognostic relevance. © 2022 John Wiley & Sons Ltd.

Introduction: The B-cell lymphoma/leukaemia 11A (BCL11A) gene encodes a Krüppel-like transcription factor involved in lymphocyte development during normal haematopoiesis. Aberrant expression of BCL11A has been observed in several haematological malignancies, including chronic lymphocytic leukaemia (CLL). However, its functions in the regulatory networks of malignant B lymphocytes are poorly understood, as are the relations to clinical course and outcome of B-cell malignancies, particularly CLL. Methods: The expression of BCL11A was analysed in peripheral blood mononuclear cells of 87 newly-diagnosed CLL patients by quantitative reverse-transcriptase polymerase chain reaction (qRT-PCR), and association with clinical and molecular variables was assessed. Results: BCL11A was significantly overexpressed in CLL samples compared to control samples (p < 0.001). BCL11A expression level exhibited no association with age, sex, leukocyte, lymphocyte and platelet counts, haemoglobin level, serum β2-microglobulin, CD38 status and cytogenetic abnormalities. On the other hand, high BCL11A expression was associated with low serum lactate dehydrogenase (p = 0.031), Binet A stage (p = 0.047) and mutated IGHV (p = 0.028). In addition, a positive correlation with BCL2/BAX mRNA ratio was observed (r = 0.36; p < 0.001). Regarding the association with the time to first treatment (TTFT), a trend towards longer median TTFT in BCL11A high- versus BCL11A low-expressing cases was detected (21 vs. 6 months; p = 0.164). Conclusion: The results of this study show that BCL11A is upregulated in CLL patients, and that high BCL11A expression at diagnosis may be associated with better prognosis. These data are consistent with the role of BCL11A expression in CLL biology, and imply its potential prognostic relevance. © 2022 John Wiley & Sons Ltd.

According to current criteria, patients with acute myeloid leukemia with normal karyotype (AML-NK) are classified as intermediate risk patients. There is a constant need for additional molecular markers that will help in substratification into more precise prognostic groups. One of the potential new markers is Ecotropic viral integration 1 site (EVI1) transcriptional factor, whose expression is dissregulated in abnormal hematopoietic process. The purpose of this study was to examine EVI1 gene expression in 104 adult AML-NK patients and on 10 healthy bone marrow donors using real-time polymerase chain reaction method, and to evaluate association between EVI1 expression level and other molecular and clinical features, and to examine its potential influence on the prognosis of the disease. Overexpression of EVI1 gene (EVI1+ status) was present in 17% of patients. Increased EVI1 expression was predominantly found in patients with lower WBC count (P = 0.003) and lower bone marrow blast percentage (P = 0.005). EVI1+ patients had lower WT1 expression level (P = 0.041), and were negative for FLT3-ITD and NPM1 mutations (P = 0.036 and P = 0.003). Patients with EVI1+ status had higher complete remission rate (P = 0.047), but EVI1 expression didn’t influence overall and disease free survival. EVI1 expression status alone, cannot be used as a new marker for more precise substratification of AML-NK patients. Further investigations conducted on larger number of patients may indicate how EVI1 expression could influence the prognosis and outcome of AML-NK patients, by itself, or in the context of other molecular and clinical parameters. © 2019, Indian Society of Hematology and Blood Transfusion.

Introduction: We evaluated a novel approach for investigation of lymphocyte dysregulation in Gaucher patients by including determination of IgH and TCR gene rearrangements together with levels of immunoglobulins, natural autoantibodies as well as presence of monoclonal protein. Materials and methods: Measurement of serum immunoglobulins, monoclonal immunoglobulins, selected autoantibodies, as well as analysis of immunoglobulin heavy chain and T cell receptor gene rearrangements. Results: Immunoglobulin disorder was detected in 29.6% patients, 40.7% demonstrated presence of B cell clonality and 44.4% demonstrated presence of autoantibodies. In five patients in our series, the presence of IgH gene rearrangement was the only detectable indicator of B cell dysfunction. TCR gene rearrangements were not found in any of the patients. Conclusion: Based on our results, we propose IgH gene rearrangements as a new biomarker for investigation of B cell dysfunction occurring as a complication of Gaucher disease. © 2012 Elsevier Inc.

Introduction: We evaluated a novel approach for investigation of lymphocyte dysregulation in Gaucher patients by including determination of IgH and TCR gene rearrangements together with levels of immunoglobulins, natural autoantibodies as well as presence of monoclonal protein. Materials and methods: Measurement of serum immunoglobulins, monoclonal immunoglobulins, selected autoantibodies, as well as analysis of immunoglobulin heavy chain and T cell receptor gene rearrangements. Results: Immunoglobulin disorder was detected in 29.6% patients, 40.7% demonstrated presence of B cell clonality and 44.4% demonstrated presence of autoantibodies. In five patients in our series, the presence of IgH gene rearrangement was the only detectable indicator of B cell dysfunction. TCR gene rearrangements were not found in any of the patients. Conclusion: Based on our results, we propose IgH gene rearrangements as a new biomarker for investigation of B cell dysfunction occurring as a complication of Gaucher disease. © 2012 Elsevier Inc.

Background: Several studies support the evidence of increased incidence of hematological complications in Gaucher disease including monoclonal and polyclonal gammopathies and blood malignancies, especially multiple myeloma. Methods: Serum concentrations of immunoglobulins and PCR analysis of the IGH gene rearrangements were performed. The clonal PCR products were directly sequenced and analyzed with the appropriate database and tools. Serum monoclonal proteins were detected and identified by electrophoresis. Results: Among 27 Gaucher patients, clonal IGH rearrangement was discovered in eight, with 5/8 having also serum monoclonal protein. Elevated immunoglobulins were detected in 9/27 patients. Follow-up data for 17 patients showed that the clonal rearrangement remained the same in four of them, however, in one patient it disappeared after the follow-up period. The remaining 12/17 patients were without previous IGH clonal rearrangement and remained so after the follow-up. Conclusions: Although clonal expansion may occur relatively early in the disease course, at least judging by the IGH gene rearrangements in Gaucher patients, the detected clones may be transient. A careful clinical follow-up in these patients is mandatory, including monitoring for lymphoid neoplasms, especially multiple myeloma. © 2018 Society of Medical Biochemists of Serbia and Montenegro. All rights reserved.

Background: Several studies support the evidence of increased incidence of hematological complications in Gaucher disease including monoclonal and polyclonal gammopathies and blood malignancies, especially multiple myeloma. Methods: Serum concentrations of immunoglobulins and PCR analysis of the IGH gene rearrangements were performed. The clonal PCR products were directly sequenced and analyzed with the appropriate database and tools. Serum monoclonal proteins were detected and identified by electrophoresis. Results: Among 27 Gaucher patients, clonal IGH rearrangement was discovered in eight, with 5/8 having also serum monoclonal protein. Elevated immunoglobulins were detected in 9/27 patients. Follow-up data for 17 patients showed that the clonal rearrangement remained the same in four of them, however, in one patient it disappeared after the follow-up period. The remaining 12/17 patients were without previous IGH clonal rearrangement and remained so after the follow-up. Conclusions: Although clonal expansion may occur relatively early in the disease course, at least judging by the IGH gene rearrangements in Gaucher patients, the detected clones may be transient. A careful clinical follow-up in these patients is mandatory, including monitoring for lymphoid neoplasms, especially multiple myeloma. © 2018 Society of Medical Biochemists of Serbia and Montenegro. All rights reserved.

Background: Chronic lymphocytic leukemia (CLL) results from the clonal expansion of mature B lymphocytes and is characterized by extreme clinical heterogeneity. One of the most reliable prognostic markers in chronic lymphocytic leukemia (CLL) is the mutational status of immunoglobulin heavy variable (IGHV) genes, which defines 2 subsets, mutated CLL (M-CLL) and unmutated CLL (U-CLL), with different clinical courses. Biased IGHV gene use between M-CLL and U-CLL clones, as well as population differences in the IGHV gene repertoire have been reported. Patients and Methods: In this study, mutational status and configuration of IGHV-IGHD-IGHJ rearrangements in 85 Serbian patients were analyzed using reverse transcriptase-polymerase chain reaction (RT-PCR) and sequencing methodology. Results: We found that 55.3% of cases belonged to M-CLL and 44.7% belonged to U-CLL, with progressive disease predominating in the unmutated subset. Most frequently expressed was the IGHV3 subgroup (55.7%), followed by IGHV1 (27.3%), IGHV4 (12.5%), IGHV5 (2.3%), IGHV2 (1.1%), and IGHV6 (1.1%). The distribution of IGHD subgroups was as follows: IGHD3, 39.1%; IGHD2, 21.8%; IGHD6, 12.6%; IGHD1, 10.3%; IGHD4, 8%; IGHD5, 6.9%; and IGHD7, 1.1%. The most frequent IGHJ gene was IGHJ4 (48.9%), followed by IGHJ6 (28.4%), IGHJ3 (11.4%), and IGHJ5 (11.4%). In 15.3% of cases, heavy complementarity-determining region 3 (VH CDR3) amino acid sequences could be assigned to previously defined stereotyped clusters. Conclusions: Our study showed a strong correlation between IGHV gene mutational status and clinical course of CLL. IGHV gene use was comparable to that obtained for Mediterranean countries, with the exception of the IGHV4 subgroup, which was underrepresented in our cohort. © 2012 Elsevier Inc. All rights reserved.

Background: Chronic lymphocytic leukemia (CLL) results from the clonal expansion of mature B lymphocytes and is characterized by extreme clinical heterogeneity. One of the most reliable prognostic markers in chronic lymphocytic leukemia (CLL) is the mutational status of immunoglobulin heavy variable (IGHV) genes, which defines 2 subsets, mutated CLL (M-CLL) and unmutated CLL (U-CLL), with different clinical courses. Biased IGHV gene use between M-CLL and U-CLL clones, as well as population differences in the IGHV gene repertoire have been reported. Patients and Methods: In this study, mutational status and configuration of IGHV-IGHD-IGHJ rearrangements in 85 Serbian patients were analyzed using reverse transcriptase-polymerase chain reaction (RT-PCR) and sequencing methodology. Results: We found that 55.3% of cases belonged to M-CLL and 44.7% belonged to U-CLL, with progressive disease predominating in the unmutated subset. Most frequently expressed was the IGHV3 subgroup (55.7%), followed by IGHV1 (27.3%), IGHV4 (12.5%), IGHV5 (2.3%), IGHV2 (1.1%), and IGHV6 (1.1%). The distribution of IGHD subgroups was as follows: IGHD3, 39.1%; IGHD2, 21.8%; IGHD6, 12.6%; IGHD1, 10.3%; IGHD4, 8%; IGHD5, 6.9%; and IGHD7, 1.1%. The most frequent IGHJ gene was IGHJ4 (48.9%), followed by IGHJ6 (28.4%), IGHJ3 (11.4%), and IGHJ5 (11.4%). In 15.3% of cases, heavy complementarity-determining region 3 (VH CDR3) amino acid sequences could be assigned to previously defined stereotyped clusters. Conclusions: Our study showed a strong correlation between IGHV gene mutational status and clinical course of CLL. IGHV gene use was comparable to that obtained for Mediterranean countries, with the exception of the IGHV4 subgroup, which was underrepresented in our cohort. © 2012 Elsevier Inc. All rights reserved.

Introduction: Acute myeloid leukemia with normal karyotype (AML-NK) is the largest group of AML patients with very heterogeneous disease outcome. In order to ensure more precise risk stratification new molecular markers have been introduced, like expression level for BAALC (Brain and Acute Leukemia, Cytoplasmic) and MN1 (Meningioma 1) genes. Methods: In this study, we investigated expression level of both genes in 111 adult AML-NK at diagnosis and examined their prognostic potential. Results: BAALC and MN1 expression were detected in about one third of the patients, and positive correlation between these two genes was found. The BAALC+/or MN1+ status was not associated with the presence of FLT3-ITD mutations, but exhibited strong correlation with NPM1wt status (P <.001). Therefore, among BAALC+/or MN1+ patients the most frequent ones were FLT3-ITD-/NPM1- double negative patients with intermediate prognosis. When BAALC+/or MN1+ patients were divided into BAALChigh/BAALClow (21/21) and MN1high/MN1low (21/22) groups, we detected that BAALChigh/or MN1high patients had a tendency toward lower complete remission rate. Also, survival analysis showed that BAALChigh/or MN1high patients had shorter disease-free survival and overall survival (OS). The most pronounced influence on prognosis was detected in FLT3-ITD-/NPM1- group of patients that are lacking reliable prognostic markers, where OS in BAALChigh/or MN1high was only 5 months vs 25 months in BAALClow/or MN1low. Conclusion: These findings indicate that BAALC and MN1 expression level could be used for more precise risk stratification of AML-NK patients and especially FLT3-ITD-/NPM1- patients, transforming this intermediate-risk group, into a group with an adverse prognosis. © 2020 John Wiley & Sons Ltd

Introduction: Acute myeloid leukemia with normal karyotype (AML-NK) is the largest group of AML patients with very heterogeneous disease outcome. In order to ensure more precise risk stratification new molecular markers have been introduced, like expression level for BAALC (Brain and Acute Leukemia, Cytoplasmic) and MN1 (Meningioma 1) genes. Methods: In this study, we investigated expression level of both genes in 111 adult AML-NK at diagnosis and examined their prognostic potential. Results: BAALC and MN1 expression were detected in about one third of the patients, and positive correlation between these two genes was found. The BAALC+/or MN1+ status was not associated with the presence of FLT3-ITD mutations, but exhibited strong correlation with NPM1wt status (P <.001). Therefore, among BAALC+/or MN1+ patients the most frequent ones were FLT3-ITD-/NPM1- double negative patients with intermediate prognosis. When BAALC+/or MN1+ patients were divided into BAALChigh/BAALClow (21/21) and MN1high/MN1low (21/22) groups, we detected that BAALChigh/or MN1high patients had a tendency toward lower complete remission rate. Also, survival analysis showed that BAALChigh/or MN1high patients had shorter disease-free survival and overall survival (OS). The most pronounced influence on prognosis was detected in FLT3-ITD-/NPM1- group of patients that are lacking reliable prognostic markers, where OS in BAALChigh/or MN1high was only 5 months vs 25 months in BAALClow/or MN1low. Conclusion: These findings indicate that BAALC and MN1 expression level could be used for more precise risk stratification of AML-NK patients and especially FLT3-ITD-/NPM1- patients, transforming this intermediate-risk group, into a group with an adverse prognosis. © 2020 John Wiley & Sons Ltd

Introduction: Patients with acute promyelocytic leukemia (APL) are characterized by the highest expression of Wilms' tumor 1 (WT1) gene compared with other subtypes of acute myeloid leukemia, and yet this molecular marker is almost never used for risk stratification and in therapy response monitoring. Methods: Quantitative assessment of Wilms' tumor 1 (WT1) gene transcripts was performed using real-time PCR method. The bone marrow samples were collected at the time of diagnosis for 47 APL patients, and for 31/47 patients during follow-up/relapse of the disease (129 samples in total). We examined how this molecular marker can be used for prognosis and minimal residual disease (MRD) monitoring. Results: Increased WT1 expression was found in 34% of patients. WT1high status was an independent unfavorable factor for early death occurrence and was associated with shorter overall survival (OS). Assessment of log reduction value of WT1 expression in paired diagnosis/complete remission samples did not reveal its impact on relapse rate, disease-free survival, and OS. Also, measurement of WT1 expression level at different time points during therapy was not a reliable method for MRD monitoring. Conclusion: Increased expression of WT1 gene detected in high proportion of APL patients could be considered as a marker for more precise risk stratification models in an attempt to further improve treatment and outcome of APL patients. © 2019 John Wiley & Sons Ltd

Introduction: Patients with acute promyelocytic leukemia (APL) are characterized by the highest expression of Wilms' tumor 1 (WT1) gene compared with other subtypes of acute myeloid leukemia, and yet this molecular marker is almost never used for risk stratification and in therapy response monitoring. Methods: Quantitative assessment of Wilms' tumor 1 (WT1) gene transcripts was performed using real-time PCR method. The bone marrow samples were collected at the time of diagnosis for 47 APL patients, and for 31/47 patients during follow-up/relapse of the disease (129 samples in total). We examined how this molecular marker can be used for prognosis and minimal residual disease (MRD) monitoring. Results: Increased WT1 expression was found in 34% of patients. WT1high status was an independent unfavorable factor for early death occurrence and was associated with shorter overall survival (OS). Assessment of log reduction value of WT1 expression in paired diagnosis/complete remission samples did not reveal its impact on relapse rate, disease-free survival, and OS. Also, measurement of WT1 expression level at different time points during therapy was not a reliable method for MRD monitoring. Conclusion: Increased expression of WT1 gene detected in high proportion of APL patients could be considered as a marker for more precise risk stratification models in an attempt to further improve treatment and outcome of APL patients. © 2019 John Wiley & Sons Ltd