Examination of the FLT3 and NPM1 mutational status in patients with acute myeloid leukemia from southeastern Poland

Extended application of BACs-on-Beads technique in prenatal diagnosis

INTRODUCTION

This study explored the application of bacterial artificial chromosomes (BACs)-on-Beads (BoBs) technique, especially its ability to detect microdeletion/microduplication regions with a single probe.

METHODS

Both chromosome karyotyping and BoBs technique were applied on a total of 2218 pregnant women. Chromosome microarray analysis (CMA) was performed on patients whose cells were reported as being abnormal by BoBs technique with a single probe.

RESULTS

Twenty-two cases were detected as microdeletion/microduplication with a single probe, which was consistent with the CMA results.

CONCLUSIONS

We believe that the microdeletion/microduplication results detected by BoBs technique with a single probe provide comprehensive guidance for prenatal diagnosis.

Evaluation of FLT3-ITD Mutations and MDR1 Gene Expression in AML Patients

BACKGROUND & OBJECTIVE

Acute myeloid leukemia (AML) is a hematopoietic malignancy caused by genetic abnormalities. Currently, molecular and genetic factors are routinely used as diagnostic and prognostic markers. FLT-3 is one of the most known diagnostic factors in AML. MDR1 gene belongs to the ATP binding cassette family; it is known as one of the chemotherapy-resistant causes of AML. We aimed to study FLT-3ITD mutations and their association with MDR1 gene expression in AML individuals.

METHODS

For investigation, 80 AML individuals and 20 healthy controls were selected. This study was done in the Cancer molecular Pathology Research Center of Mashhad University of Medical Sciences (MUMS), Iran during 2017-2019. FLT3-ITD mutation was assessed by polymerase chain reaction (PCR); Real-time quantitative PCR was performed to measure the amount of MDR1 gene expression. Bone marrow and blood smears of patients were evaluated in terms of morphology. SPSS 16.0 was used for data analysis.

RESULTS

FLT3-ITD mutation and MDR1 overexpression were found in 18.8% and 23.8% of AML patients, respectively. Statistical analysis did not show any relationship or association between these two markers. Cuplike morphology was observed in blast cells in 21.25% of AML cases, which was associated with the presence of FLT3-ITD mutation.

CONCLUSION

FLT-3 and MDR1 function independently. Survival studies to determine the exact role of MDR1 overexpression in drug resistance issues would be suggested.

WT1 Gene Mutations, rs16754 Variant, and WT1 Overexpression as Prognostic Factors in Acute Myeloid Leukemia Patients

(1) Background: The aim of our study was the complex assessment of WT1 variants and their expression in relation to chromosomal changes and molecular prognostic markers in acute myeloid leukemia (AML). It is the first multidimensional study in Polish AML patients; (2) Methods: Bone marrow aspirates of 90 AML patients were used for cell cultures (banding techniques and fluorescence in situ hybridization), and to isolate DNA (WT1 genotyping, array comparative genomic hybridization), and RNA (WT1 expression). Peripheral blood samples from 100 healthy blood donors were used to analyze WT1 rs16754; (3) Results: Allele frequency and distribution of WT1 variant rs16754 (A;G) did not differ significantly among AML patients and controls. Higher expression of WT1 gene was observed in AA genotype (of rs16754) in comparison with GA or GG genotypes—10,556.7 vs. 25,836.5 copies (p = 0.01), respectively. WT1 mutations were more frequent in AML patients under 65 years of age (p < 0.0001) and affected relapse-free survival (RFS). The presence of NPM1 or CEBPA mutations decreased the risk of WT1 mutation presence, odds ratio (OR) = 0.11, 95% CI 0.02−0.46, p = 0.002 or OR = 0.05, 95% CI 0.006−0.46, p = 0.002, respectively. We observed significantly higher WT1 expression in AML CD34+ vs. CD34−, −20,985 vs. 8304 (p = 0.039), respectively. The difference in WT1 expression between patients with normal and abnormal karyotype was statistically insignificant; (4) Conclusions: WT1 gene expression and its rs16754 variant at diagnosis did not affect AML outcome. WT1 mutation may affect RFS in AML.

TERT rs2853669 as a predictor for overall survival in patients with acute myeloid leukaemia

INTRODUCTION

the aim of the study was to investigate the contribution of TERT rs2736100 and rs2853669 gene polymorphisms in defining the genetic predisposition to acute myeloid leukaemia (AML), their association with different prognostic markers, and their impact on survival, outcome, and the prognosis of affected patients. Also, we investigated the association of TERT SNPs in AML in the presence or absence of DNMT3A (R882), NPM1, and FLT3 mutations.

MATERIAL AND METHODS

A total of 509 participants were enrolled in our study, consisting of 146 AML patients and 363 healthy participants, with no history of malignancy. TERT rs2736100 and rs2853669 polymorphisms were genotyped by using TaqMan SNP genotyping assay FLT3 (ITD, D835), DNMT3A (R882), and NPM1 c.863_864insTCTG (type A) mutations were analised in each AML case.

RESULTS

TERT rs2736100 and rs2853669 were not associated with AML risk in the codominant, dominant, recessive, or allelic models. Multivariate Cox regression showed that TERT rs2853669 was a significant predictor for overall survival in AML patients. After adjusting for age, gender, cytogenetic risk group, ECOG status, FLT3, DNMT3A, NPM1 mutation, AML subtype, and treatment, the estimated adjusted hazard ratio (HR adjusted = 1.54, 95% CI: 1.01-2.35) showed that the TERT rs2853669 variant genotype had a negative influence on survival time.

CONCLUSIONS

TERT rs2853669 and rs2736100 polymorphisms were not risk factors for developing AML in the Romanian population, but the TERT rs2853669 variant genotype had a negative effect on AML patients' overall survival in the presence of other known prognostic factors.

Combined Expression of CD34 and FLT3-Internal Tandem Duplication Mutation Predicts Poor Response to Treatment in Acute Myeloid Leukemia

Background

Acute myeloid leukemia (AML) is a common hematological malignancy associated with different cytogenetic and genetic abnormalities.

Methods

FLT3-internal tandem duplication (FLT3/ITD) mutation and CD34 expression levels were assessed in the bone marrow (BM) aspirates of 153 de novo AML patients. Data were correlated with relevant clinic-pathological features of the patients, response to treatment, disease-free survival (DFS), and overall free survival (OS) rates.

Results

FLT3-ITD mutation was detected in 27/153 (17.6%) AML patients (P=0.001), and CD34 was expressed in 83/153 (54.2%) patients (P=0.293) compared to those with wild FLT3 and CD34⁻ expression, respectively. Patients with FLT3-ITD mutation showed increased peripheral blood and BM blast cells, abnormal cytogenetics, poor DFS and OS compared to those with wild FLT3 (P=0.013, P<0.001, P=0.010, P=0.008 and P=0.004, respectively), while there was no significant association with response to treatment (P=0.081). There was no significant association between CD34 expression and response to treatment, DFS, and OS (P>0.05). FLT3-ITD mutation and FAB subtypes were independent prognostic factors for DFS. Older age ≥39 years, HB <7 mg/dL PB blast ≥54%, and FLT3-ITD mutation were independent prognostic factors for poor OS in AML patients. The presence of both FLT3-ITD mutation and CD34 expression associated significantly with resistance to therapy (P=0.024), short DFS and OS rates (P=0.006, P=0.037, respectively).

Conclusion

Combined expression of both FLT3-ITD mutation and CD34 expression is an important prognostic and predictive factor for poor disease outcome in AML patients.

Prevalence and Clinical Significance of FLT3 and NPM1 Mutations in Acute Myeloid Leukaemia Patients of Assam, India

Acute Myeloid Leukaemia (AML) is one of the common forms of haematological malignancy in adults. We analysed the prevalence and clinical significance of FMS-like tyrosine kinase 3 (FLT3) and Nucleophosmin 1 (NPM1) mutations in AML patients of North East India. Co-prevalence and clinical significance of three recurrent chromosomal translocations namely t(15; 17), t(8; 21), t(16; 16) and expression of epidermal growth factor receptor (EGFR), flow markers were also documented and co-related with disease progress. We analysed bone marrow aspirates or peripheral blood samples from 165 newly diagnosed AML patients. All clinical samples were analysed by Real Time PCR and DNA sequencing based assays. NPM1 was the most frequently detected mutation in the study population (46/165 = 27.90%, 95% CI 20.75-35.05). FLT3 mutations were detected in 27/165 (16.40%, 95% CI 10.45-22.35) patients with internal tandem duplication (FLT3-ITD) in 24/165 (14.60%, 95% CI 8.91-20.29) and FLT3-D835 in 3/165 (1.80%, 95% CI 0-4.13) patients. NPM1 mutations were associated with a higher complete remission rate and longer overall survival (P < 0.01) compared to FLT3-ITD whereas FLT3-ITD showed adverse impact with poor survival rate (P < 0.01), leukocytosis (P < 0.01) and a packed bone marrow. EGFR expression was more in patients with NPM1 mutation compared to FLT3 mutation (P = 0.09). Patients with FLT3 and NPM1 mutations uniformly expressed CD13 and CD33 whereas CD34 was associated with poor prognosis (P ≤ 0.01) in patients with NPM1 mutation. FLT3-ITD was associated with inferior overall survival. However the clinical significance of FLT3-D835 was not clear due to small number of samples. NPM1 mutation showed better prognosis with increased response to treatment in the absence of FLT3-ITD.