Cytogenetic Abnormalities In Acute Myeloid Leukemia Research Articles

C-Kit and Flt3 mutation status in acute myeloid leukaemia with cytogenetic correlation and prognosis: A series of 75 cases

Recent WHO classification (5 edition) has included Acute Myeloid Leukaemia (AML) with mutations in NPM1, CEBPA as separate entities along with AML with cytogenetic abnormalities in AML with recurrent genetic abnormalities. Even though C-kit and FLT3 mutations in AML have no diagnostic importance, prognostic significance in different subtypes of AML for the presence of these mutations are not the same.To assess the correlation between French American British (FAB) AML classification, specific cytogenetic abnormalities with C-kit, and FLT3 mutation in AML and to evaluate the prognosis and survival of AML patients with respect to cytogenetic abnormalities and C-kit and FLT3 mutation status. Retrospectively all AML cases in which C-kit and FLT3 mutation status was assessed were retrieved; C-kit D816V mutation status had been assessed by Real time PCR; For FLT3 mutation, both Internal tandem duplication (ITD) and D835V mutation status had been assessed using PCR and gel electrophoresis; The data regarding morphological with immunophenotypic diagnosis, conventional karyotyping, FISH for translocation 8;21 (t (8;21)) and inversion16 / translocation16;16 (t (16;16) were also retrieved in all these cases along with follow-up from hospital records. Total 75 cases were included; Male/ Female ratio was 1.21:1 (41/34); Median age was 31 (Range: 2 - 64); 18 cases had translocation 8;21 (t (8;21)); 3 cases showed inversion16 / translocation16;16 (t (16;16); Out of the 18 cases which showed t (8;21), 10 cases had associated loss of sex chromosome. Eight cases had C-kit D816V mutation; three of which had t (8;21) while two had inversion 16. 12 cases had FLT3 mutations among which nine were ITD while three had D835V mutation. On karyotyping, one of these cases showed hyperdiploidy while the majority had normal karyotype. A single case had both C-kit D816V mutation and FLT3 D835V mutation with inversion 16 on karyotyping; Most common type of AML in both cases with FLT3 mutation and C-kit mutation was AML-M2 (FAB); Commonest karyotyping abnormality for cases with C-kit mutation was t(8;21); while for FLT3 mutation, the majority had normal karyotype; The single case which had both C-kit D816V mutation and FLT3 D835V mutation was alive event-free at three-year follow-up. Both FLT3 ITD and TKD mutations had a worse prognosis in our study. However, AML cases with C-kit mutation had a similar prognosis comparable to C kit negative cases. A large-scale study is required to elucidate the significance of this.

Whole transcriptome sequencing reveals HOXD11-AGAP3, a novel fusion transcript in the Indian acute leukemia cohort.

Introduction: Acute leukemia is a heterogeneous disease with distinct genotypes and complex karyotypes leading to abnormal proliferation of hematopoietic cells. According to GLOBOCAN reports, Asia accounts for 48.6% of leukemia cases, and India reports ~10.2% of all leukemia cases worldwide. Previous studies have shown that the genetic landscape of AML in India is significantly different from that in the western population by WES. Methods: We have sequenced and analyzed 9 acute myeloid leukemia (AML) transcriptome samples in the present study. We performed fusion detection in all the samples and categorized the patients based on cytogenetic abnormalities, followed by a differential expression analysis and WGCNA analysis. Finally, Immune profiles were obtained using CIBERSORTx. Results: We found a novel fusion HOXD11-AGAP3 in 3 patients, BCR-ABL1 in 4, and KMT2A-MLLT3 in one patient. Categorizing the patients based on their cytogenetic abnormalities and performing a differential expression analysis, followed by WGCNA analysis, we observed that in the HOXD11-AGAP3 group, correlated co-expression modules were enriched with genes from pathways like Neutrophil degranulation, Innate Immune system, ECM degradation, and GTP hydrolysis. Additionally, we obtained HOXD11-AGAP3-specific overexpression of chemokines CCL28 and DOCK2. Immune profiling using CIBRSORTx revealed differences in the immune profiles across all the samples. We also observed HOXD11-AGAP3-specific elevated expression of lincRNA HOTAIRM1 and its interacting partner HOXA2. Discussion: The findings highlight population-specific HOXD11-AGAP3, a novel cytogenetic abnormality in AML. The fusion led to alterations in immune system represented by CCL28 and DOCK2 over-expression. Interestingly, in AML, CCL28 is known prognostic marker. Additionally, non-coding signatures (HOTAIRM1) were observed specific to the HOXD11-AGAP3 fusion transcript which are known to be implicated in AML.

Identification of a Novel Unbalanced t(4;8) (q12;q24) in Paediatric Acute Myeloid Leukemia M2 with AML-ETO Negative Patient by Fluorescence in Situ Hybridization Technique

Identification of chromosomal abnormalities in patients with Acute Myeloid Leukemia (AML) has contributed substantially to our current understanding of the molecular pathogenesis underlying leukemogenesis, and risk-stratification. Based on molecular abnormalities both influences treatment strategies and aids in determining prognosis. While over 300 established mutations have been documented in AML, the enhanced availability of genetic analysis and the increase in awareness of uncommon chromosomal translocations have made it possible for rare, apparently unique translocations to become recognized and to ultimately gain prognostic significance. Hence, we present a case of AML with a novel, t(4;8) involving breakpoints previously undescribed. Although the patient required second induction, first remission was ultimately achieved. While the prognostic significance of this translocation is not fully elucidated, it is our hope that documentation of this patient’s presentation will help to characterize the significance of a yet undefined cytogenetic abnormality in AML.

Evaluation of multiprobe fluoresence in-situ hybridization panel in the detection of common chromosomal abnormalities of acute myeloid leukemia

Background Numerous recurrent chromosomal aberrations have been identified in acute myeloid leukemia (AML), and their detection has become essential for accurate diagnosis, classification, and prognosis of the disease. Fluorescence in-situ hybridization (FISH) provides a powerful technique complementary and even alternative to chromosome banding studies for the identification of selected chromosome aberrations. Aim Evaluation of the multiprobe FISH panel in the detection of common cytogenetic abnormalities in AML and to investigate their association with clinical diagnosis, chemotherapy, and prognosis. Patients and methods This study was conducted on 20 newly diagnosed AML patients. All patients were subjected to full history taking, clinical examination, laboratory investigations including complete blood count, bone marrow aspiration, immunophenotyping, and interphase FISH using cytocell multiprobe AML/myelodysplastic syndrome panel designed to detect AML/Eight-twenty-one (ETO), Promyelocytic leukaemia- Retinoic acid receptor alpha (PML-RARA), and core-binding factor beta/Myosin, heavy chain 11, smooth muscle (CBFβ/MYH11) translocations, mixed-lineage leukaemia (MLL) break apart, P53, 5q, 7q, and 20q deletions. Results Interphase FISH analysis showed 5q deletion in 8/20 (40%) cases, positive PML/RARA in 3/20 (15%) cases p53 deletion in 15/20 (75%) cases, positive AML1/ETO in 1/20 (5%) cases, no MLL break apart cases (0%), 7q deletion in 4/20 (20%) cases, positive CBFβ/MYH11 fusion gene in 4/20 (20%) cases, 20q deletion in 9/20 (45%) cases, and trisomy 8 in 7/20 (35%) cases. There was a statistically significant relationship between 5q deletion and prognosis (P=0.028). Conclusion Multiprobe FISH is more cost effective and time effective compared with traditional FISH. It is an efficient technique for the detection of cytogenetic aberrations AML, providing critical information for diagnosis and prognosis, and for monitoring the course of the disease.

17p− Syndrome Arising from a Novel Dicentric Translocation in a Patient with Acute Myeloid Leukemia

The cytogenetic contribution to the poor prognosis when myelodysplastic syndrome (MDS) progresses to acute myeloid leukemia (AML) is not well understood. We present a 66-year-old male who had thrombocytopenia with dysplastic features in peripheral blood neutrophils (hypogranular, hyposegmented neutrophils) comprising the Pelger-Huet anomaly, increased blasts in the marrow, and markers consistent with AML. Diagnostic marrow cytogenetics showed a complex karyotype including del(5q), a novel unbalanced dicentric translocation, t(17;20), resulting in both del(20q) and del(17p). Fluorescence in situ hybridization (with probe TP53) showed deletion of 17p13 on the dicentric chromosome, completing the criteria for the 17p − syndrome. Fluorescence in situ hybridization with probes for two tumor suppressor genes on chromosome 5q also showed deletion ( CSF1R [at 5(q33.2–q33.4) and EGR-1 [5(q31–q32)]). Remission was difficult to achieve and cytogenetic relapse occurred 6 months postdiagnosis, and clinical relapse approximately one month later. Our case provides a novel mechanism for the 17p − syndrome, and highlights the difficulty of attributing prognostic significance to a particular cytogenetic abnormality in AML.