Detection of TET2, KRAS and CBL variants by Next Generation Sequencing and analysis of their correlation with JAK2 and FLT3 in childhood AML

Background: Acute myeloid leukemia [AML] is a heterogeneous clonal disorder in terms of cytogenetic and molecular aberrations. Ten-Eleven-Translocation 2 [TET2], Kirsten rat sarcoma viral oncogene homolog [KRAS], and Casitas B-cell lymphoma [CBL] have an important role pathogenesis of acute myeloid leukemia [AML] and their activated mutations confer proliferative and survival signals

Aim: In this study, we aimed to find possible genetic markers for molecular analysis in childhood AML by screening hot-spot exons of TET2, KRAS, and CBL using Next Generation Sequencing [NGS] analysis. In addition, association between found variants and mutations of Januse Kinase-2 [JAK2] and Fms-Related Tyrosine Kinase [FLT3] were analyzed which are important prognostic risk factors for AML

Methods: Eight patients who were diagnosed with pediatric AML at Losante Pediatric Hematology- Oncology Hospital were included to the study. Hot-spot exons of TET2, KRAS and CBL genes were screened using the NGS method. Furthermore, FLT3-Internal Tandem Duplicate [FLT3-ITD] and JAK2-V617F were analyzed by Real Time Polymerase chain Reaction [Real Time-PCR]

Results: In total, we identified 20 variants in studied genes by NGS. In our patient group, 16 variants in the TET2 [seven novel, seven missense and two silent], two variants in the KRAS [one missense and one intronic] and two variants in the CBL [two novel] were found. All of AML patients were found negative for JAK V617 F. Three of the eight patients [37.5%] showed mutations of both FLT3-ITD and TET2, KRAS, CBL

Conclusion: We found novel mutations forTET2, KRAS, and CBL. The detected variants in this article seem to be the first screening results of genes studied by NGS in childhood AML patients. Our results also showed some degree of association between FLT3-ITD and TET2, KRAS, CBL mutations

Why are mini-implants lost: The value of the implantation technique!

The use of mini-implants have made a major contribution to orthodontic treatment. Demand has aroused scientific curiosity about implant placement procedures and techniques. However, the reasons for instability have not yet been made totally clear. The aim of this article is to establish a relationship between implant placement technique and mini-implant success rates by means of examining the following hypotheses: 1) Sites of poor alveolar bone and little space between roots lead to inadequate implant placement; 2) Different sites require mini-implants of different sizes! Implant size should respect alveolar bone diameter; 3) Properly determining mini-implant placement site provides ease for implant placement and contributes to stability; 4) The more precise the lancing procedures, the better the implant placement technique; 5) Self-drilling does not mean higher pressures; 6) Knowing where implant placement should end decreases the risk of complications and mini-implant loss.

O uso de mini-implantes trouxe grandes contribuições ao tratamento ortodôntico. Essa demanda gerou curiosidade científica sobre os procedimentos e técnicas de implantação. Entretanto, instabilidades desses dispositivos ocorrem por motivos ainda não totalmente esclarecidos. Objetiva-se, com esse trabalho, relacionar a técnica de implantação com a taxa de sucesso dos mini-implantes por meio das seguintes hipóteses: 1) áreas com osso alveolar pobre e com pouco espaço inter-radicular levam à inadequada implantação; 2) diferentes áreas requerem distintos tamanhos de mini-implantes! O tamanho do implante deve acompanhar o diâmetro do osso alveolar; 3) a correta determinação do local em que será colocado o mini-implante facilita a instalação e contribui para a estabilidade; 4) quanto mais precisa for a lancetagem, melhor será a técnica de implantação; 5) autoperfuração não significa alta pressão; 6) saber onde finalizar a implantação diminui a incidência de complicações e de perda dos mini-implantes.

Incidences and Prognostic Impact of c-KIT, WT1, CEBPA, and CBL Mutations, and Mutations Associated With Epigenetic Modification in Core Binding Factor Acute Myeloid Leukemia: A Multicenter Study in a Korean Population

BACKGROUND: To identify potential molecular prognostic markers in core binding factor (CBF) AML, we analyzed incidences and prognostic impacts of mutations in c-KIT, WT1, CEBPA, CBL, and a number of epigenetic genes in CBF AML. METHODS: Seventy one and 21 AML patients with t(8;21) and inv(16) were enrolled in this study, respectively. NPM1, CEBPA, c-KIT, IDH1/2, DNMT3A, EZH2, WT1, and CBL mutations were analyzed by direct sequencing. Patients were categorized with respect to c-KIT and WT1 mutation status, and both clinical features and prognoses were compared. RESULTS: The incidences of FLT3 internal tandem duplication (ITD), NPM1, CEBPA, IDH1/2, DNMT3A, EZH2, and CBL mutations were low (< or =5%) in CBF AML patients. However, c-KIT and WT1 mutations occurred frequently (10.9% and 13.8%, respectively). t(8;21) patients with c-KIT mutations showed significantly shorter overall survival (OS) and disease free survival (DFS) periods than those without mutations (P<0.001, for both); however, although the limited number of t(8;21) patients were analyzed, WT1 mutation status did not affect prognosis significantly. Relapse or death during follow-up occurred more frequently in t(8;21) patients carrying c-KIT mutations than in those without the mutation, although the difference was significant only in a specific patient subgroup with no WT1 mutations (P=0.014). CONCLUSIONS: The incidences of mutations in epigenetic genes are very low in CBF AML; however, c-KIT and WT1 mutations occur more frequently than others. The poor prognostic impact of c-KIT mutation in t(8;21) AML patients only applies in a specific patient subgroup without WT1 mutations. The prognostic impact of WT1 mutation in CBF AML is not evident and further investigation is required.