Sex-Biased Transcription Expression of Vitellogenins Reveals Fusion Gene and MicroRNA Regulation in the Sea Louse Caligus rogercresseyi.

The caligid ectoparasite, Caligus rogercresseyi, is one of the main concerns in the Chilean salmon industry. The molecular mechanisms displayed by the parasite during the reproductive process represent an opportunity for developing novel control strategies. Vitellogenin is a multifunctional protein recognized as a critical player in several crustaceans' biological processes, including reproduction, embryonic development, and immune response. This study aimed to characterize the C. rogercresseyi vitellogenins, including discovering novel transcripts and regulatory mechanisms associated with microRNAs. Herein, vitellogenin genes were identified by homology analysis using the reference sea louse genome, transcriptome database, and arthropods vitellogenin-protein database. The validation of expression transcripts was conducted by RNA nanopore sequencing technology. Moreover, fusion gene profiling, miRNA target analysis, and functional validation were performed using luciferase assay. Six putative vitellogenin genes were identified in the C. rogercresseyi genome with high homology with other copepods vitellogenins. Furthermore, miR-996 showed a putative role in regulating the Cr_Vitellogenin1 gene, which is highly expressed in females. Moreover, vitellogenin-fusion genes were identified in adult stages and highly regulated in males, demonstrating sex-related expression patterns. In females, the identified fusion genes merged with several non-vitellogenin genes involved in biological processes of ribosome assembly, BMP signaling pathway, and biosynthetic processes. This study reports the genome array of vitellogenins in C. rogercresseyi for the first time, revealing the putative role of fusion genes and miRNA regulation in sea lice biology.

Fusion genes aiding the diagnosis of soft tissue tumours of the oral cavity: From bench to bedside.

Soft tissue tumours (STT) are a heterogeneous group of benign, malignant, and intermediate/borderline mesenchymal tumours. In the oral and maxillofacial region, less than 3% of all lesions correspond to benign STT and <1% are sarcomas. Overlapping microscopic features may lead to quite challenging diagnostic processes. Translocations and fusion genes are frequent, and type-specific genetic alterations are detected in these tumours. The detection of such alterations by classic cytogenetic, FISH, RT-PCR or NGS can help to define the diagnosis. This narrative review aims to review fusion genes reported for STT that affect the oral cavity and their use in diagnostic molecular pathology. Basic concepts regarding mechanisms of fusion genes formation are presented to clarify this information for surgical pathologists. The chromosomal rearrangements and fusion genes of adipocytic, fibroblastic and myofibroblastic, vascular, pericytic, smooth muscle, skeletal muscle, chondro-osseous, and uncertain origin STT are summarised. The advance in molecular pathology techniques has led not only to a better understanding of the molecular pathogenesis of STT, but also to the development of helpful diagnostic tools. Therefore, it is important for the oral and head and neck pathologists to familiarise with the signature rearrangements and fusion genes for each tumour.

Electrochemical DNA biosensor for chronic myelocytic leukemia based on hybrid nanostructure.

The present research refers to elaborating a new label-free electrochemical biosensor used to detect the BCR/ABL fusion gene. We used a hybrid nanocomposite composed of chitosan and zinc oxide nanoparticles (Chit-ZnONP) immobilized on a polypyrrole (PPy) film. DNA segments were covalently immobilized, allowing biomolecular recognition. Atomic force microscopy (AFM), cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS) were used to evaluate the assembly stages of the biosensor. The biosensor's analytical performance was investigated using recombinant plasmids containing the target oncogene and clinical samples from patients with chronic myeloid leukemia (CML). A limit of detection (LOD) of 1.34 fM, limit of quantification (LOQ) of 4.08 fM, and sensitivity of 34.03 µA fM-1 cm2 were calculated for the BCR/ABL fusion oncogene. The sensing system exhibited high specificity, selectivity, and reproducibility with a standard deviation (SD) of 4.21%. Additionally, a linear response range was observed between 138.80 aM to 13.88 pM with a regression coefficient of 0.96. Also, the biosensor shows easy operationalization and fast analytical response, contributing to the early cancer diagnosis. The proposed nanostructured device is an alternative for the genetic identification BCR/ABL fusion gene.

Low Prevalence of ETV6::RUNX1 Fusion Gene in a Hispanic Population.

ETV6::RUNX1 is a genetic rearrangement of good prognosis in children with acute lymphoblastic leukemia (ALL). In Mexico, its prevalence is low in comparison with Caucasian populations. We developed a novel TaqMan one-step RT-qPCR approach to assess the prevalence of four genetic rearrangements in a cohort of Hispanic children with ALL from Mexico City. The prevalence of common fusion gene transcripts was as follows: TCF3::PBX1 7.7%; BCR::ABL1p 190 3.3%; and KMT2A::AFF1 2.8%, and ETV6::RUNX1was observed with low prevalence (10.5%) in comparison to that reported for developed countries. This is consistent with previous findings on Mexican children with ALL and similar to those reported on children from Hispanic populations. The confirmation of a low prevalence of ETV6::RUNX1 in children of a Hispanic origin represents an advancement in the description of genetic factors of ALL in these populations.

A Recombinant Turkey Herpesvirus Expressing the F Protein of Newcastle Disease Virus Genotype XII Generated by NHEJ-CRISPR/Cas9 and Cre-LoxP Systems Confers Protection against Genotype XII Challenge in Chickens.

In this study, we developed a new recombinant virus rHVT-F using a Turkey herpesvirus (HVT) vector, expressing the fusion (F) protein of the genotype XII Newcastle disease virus (NDV) circulating in Peru. We evaluated the viral shedding and efficacy against the NDV genotype XII challenge in specific pathogen-free (SPF) chickens. The F protein expression cassette was inserted in the unique long (UL) UL45-UL46 intergenic locus of the HVT genome by utilizing a clustered regularly interspaced short palindromic repeat (CRISPR)/Cas9 gene-editing technology via a non-homologous end joining (NHEJ) repair pathway. The rHVT-F virus, which expressed the F protein stably in vitro and in vivo, showed similar growth kinetics to the wild-type HVT (wtHVT) virus. The F protein expression of the rHVT-F virus was detected by an indirect immunofluorescence assay (IFA), Western blotting, and a flow cytometry assay. The presence of an NDV-specific IgY antibody was detected in serum samples by an enzyme-linked immunosorbent assay (ELISA) in SPF chickens vaccinated with the rHVT-F virus. In the challenge experiment, the rHVT-F vaccine fully protects a high, and significantly reduced, virus shedding in oral at 5 days post-challenge (dpc). In conclusion, this new rHVT-F vaccine candidate is capable of fully protecting SPF chickens against the genotype XII challenge.

Molecular investigation of human metapneumovirus in children with acute respiratory infections in Chennai, South India, from 2016-2018.

Human metapneumovirus (hMPV) has emerged as a frequent cause of acute respiratory infections (ARI) among young children. The prevalence and genetic diversity of hMPV circulating in Chennai, Southern India, has not been studied yet. Hence, this study was aimed to investigate the prevalence, co-infection with other respiratory viruses like HRSV A and B, influenza A and B, hRV and HPIV 1-4 viruses, socio-demographic associations, and genotypes of hMPV among children in Chennai. A total of 350 nasal swab specimens were collected from children with ARI during April 2016 to August 2018 and tested for hMPV by real time PCR method. In this study, hMPV was detected in 4% (14/350) of the samples. One hMPV positive sample was found to be co-infected with influenza B virus. The mean and median ages of the children with hMPV infection were 61.5 months (5.1 years) and 83 months (6.9 years), respectively. Phylogenetic analysis of the partial F gene revealed the presence of A2c subcluster among the study strains as well as with B1 and B2 lineages. The prevalence data obtained in this study is important in evaluating the role of hMPV in childhood ARI and emphasizes the importance of routine viral diagnosis in hospitals. To the best of our knowledge, this is the first study to report the prevalence, seasonality, and genetic diversity of hMPV in Chennai as well as the first study to report A2c subcluster of hMPV among children in India.

Pediatric Acute Promyelocytic Leukemia: Epidemiology, Molecular Features, and Importance of GST-Theta 1 in Chemotherapy Response and Outcome.

Previous studies have suggested a variation in the incidence of acute promyelocytic leukemia (APL) among the geographic regions with relatively higher percentages in the Latin American population. We aimed to explore the population burden of pediatric APL, gathering information from the population-based cancer registry (PBCR) and the diagnosis of APL obtained through incident cases from a hospital-based cohort. The homozygous deletion in glutathione S-transferases (GSTs) leads to a loss of enzyme detoxification activity, possibly affecting the treatment response. Mutations in the RAS pathway genes are also considered to be a key component of the disease both in the pathogenesis and in the outcomes. We have assessed mutations in a RAS-MAP kinase pathway (FLT3, PTPN11, and K-/NRAS) and GST variant predisposition risk in the outcome. Out of the 805 children and adolescents with acute myeloid leukemia (AML) who are registered in the PBCR, 35 (4.3%) were APL cases. The age-adjusted incidence rate (AAIR) was 0.03 per 100,000 person-years. One-hundred and sixty-three patients with APL were studied out of 931 AML cases (17.5%) from a hospital-based cohort. Mutations in FLT3, KRAS, and NRAS accounted for 52.1% of the cases. Patients with APL presented a 5-year probability of the overall survival (OS) of 67.3 ± 5.8%. A GST-theta 1 (GSTT1) null genotype conferred adverse prognosis, with an estimated hazard ratio of 2.8, 95% confidence interval (CI) 1.2-6.9. We speculate that the GSTT1 polymorphism is associated with therapeutics and would allow better OS of patients with APL with a GSTT1 null genotype.

Casos atípicos e14a3 (b3a3) en el gen de fusión BCR-ABL de la leucemia mieloide crónica en Cuba / Rare cases of e14a3 (b3a3) BCR-ABL fusion in chronic myeloid leukemia in Cuba

Introducción: La leucemia mieloide crónica es un desorden clonal maligno de células madres hematopoyéticas pluripotentes que se caracteriza por la presencia del cromosoma Filadelfia, consecuencia de la traslocación cromosómica recíproca entre los brazos largos de los cromosomas 9 y 22. El resultado de esta alteración cromosómica es un gen de fusión que contiene las uniones b2a2 (e13a2) o b3a2 (e14a2). En la mayor parte de los casos, las células de la leucemia mieloide crónica expresan uno de los dos transcritos (b2a2 o b3a2); sin embargo, el 5 por ciento de los pacientes tienen ambos tipos de ARNm como resultado de empalmes alternativos. Se han encontrado otros transcriptos como e19a2, e2a2, e1a3, e6a2, e13a3(b2a3), y e14a3(b3a3), que ocurren con menos frecuencia. Objetivo: Describir el comportamiento de dos pacientes con leucemia mieloide crónica que presentan un trascripto BCR/ABL atípico. Casos clínicos: En el estudio molecular por reacción en cadena de la polimerasa cualitativo realizado a los dos pacientes, se observó un punto de ruptura del gen de fusión BCR/ABL poco frecuente, el cual se correspondía al transcripto e14a3 (b3a3). Estos pacientes iniciaron tratamiento con mesilato de imatinib a dosis de 400 mg diarios. Al primer paciente a los dos meses de tratamiento se le detectó crisis blástica, por lo que se le cambió el tratamiento a nilotinib 400 mg diarios que mantiene hasta la actualidad. La segunda paciente mantuvo igual tratamiento, aunque en ocasiones ha sido necesario incorporar tratamiento citorreductor con hidroxiurea por presentar leucocitosis. Conclusiones: Los pacientes con BCR/ABL a3 presentan un curso más benigno de la enfermedad. Aunque en los pacientes estudiados no se observó una respuesta satisfactoria al tratamiento pues presentaron diversas complicaciones(AU)

Introduction: Chronic myeloid leukemia is a malignant clonal disorder of pluripotent hematopoietic stem cells and characterized by the presence of the Philadelphia chromosome, which is the product of a reciprocal translocation between the long arms of chromosomes 9 and 22. The result of this chromosomal alteration is a fusion gene that contains the e13a2 (b2a2) and e14a2 (b3a2) junctions. In most cases, chronic myeloid leukemia cells express one of the two transcripts (b2a2 or b3a2); however, 5 percent of patients have both types of mRNA, as a result of alternative junctions. Other transcripts have been identified, such as e19a2, e2a2, e1a3, e6a2, e13a3 (b2a3), and e14a3 (b3a3), which occur less frequently. Objective: To describe the behavior of two patients with chronic myeloid leukemia who have an atypical BCR-ABL transcript. Clinical cases: In a qualitative molecular study of polymerase chain reaction carried out with two patients, a BCR-ABL fusion gene breakpoint was observed, which corresponded to the e14a3 (b3a3) transcript. These patients started treatment with imatinib mesylate at a dose of 400mg/d. At two months, the first patient had a diagnose of blast crisis, so the treatment was changed to nilotinib at a dose of 400mg/d, which the patient maintained to date. The second patient maintained the same treatment, although it was sometimes necessary to incorporate cytoreductive treatment with hydroxyurea due to leukocytosis. Conclusions: Patients with BCR-ABL a3 present a more benign evolution of the disease. However, a satisfactory response to treatment was not observed in the patients studied, as long as they presented various complications(AU)

Isolation and genetic characterization of virulent strains of avian paramyxovirus-1 from multiple avian species in Azad Jammu and Kashmir 2017-2018.

Despite intensive vaccination, endemicity of Avian paramyxoviruses-1 (APMV-1) is a significant problem in developing countries in Africa, Middle East, and Asia. Given the importance of APMV-1 in poultry and multiple non-poultry avian species, it is important to continue surveillance programs, routine monitoring and characterization of field isolates in the region where viruses are endemic. The purpose of this study was to pathotyped and genetically characterized 21 APMV-1s isolated from multiple avian species reared in different regions of Azad Jammu and Kashmir (AJK). Phylogenetic analysis based on complete fusion (F) gene sequences showed that 17 APMV-1 isolates obtained from commercial poultry and backyard birds belonged to sub-genotype VIIi. Though, one pigeon-origin APMV-1 isolate was clustered in sub-genotype VIg and three in recently designated new sub-genotype VIm of genotype VI. The pigeon-origin isolates had the following two motifs 113-RKKR↓F-117 and 113-RQRR↓F-117, while all other isolates had the polybasic amino acid sequence 113-RQKR↓F-117 at the F-cleavage site, which is characteristic of virulent APMV-1 strains. These results are consistent with the five viruses that had intracerebral pathogenicity indices (ICPIs) of between 1.50 and 1.73, corresponding to a velogenic pathotype. The APMV-1s isolated from commercial poultry and backyard birds in this study showed low nucleotide distance (0.3-0.9%) and genetically closely related (> 97%) to viruses repeatedly isolated (2011-2017) from multiple avian species in other states of Pakistan. Strengthened surveillance programs in both commercial poultry and backyard flocks are needed to better assess the commercial-backyard bird interface and form a basis for evidence-based measures to limit and prevent APMV-1 transmission.

Identification and Characterization of Novel Fusion Genes with Potential Clinical Applications in Mexican Children with Acute Lymphoblastic Leukemia.

Acute lymphoblastic leukemia is the most common type of childhood cancer worldwide. Mexico City has one of the highest incidences and mortality rates of this cancer. It has previously been recognized that chromosomal translocations are important in cancer etiology. Specific fusion genes have been considered as important treatment targets in childhood acute lymphoblastic leukemia (ALL). The present research aimed at the identification and characterization of novel fusion genes with potential clinical implications in Mexican children with acute lymphoblastic leukemia. The RNA-sequencing approach was used. Four fusion genes not previously reported were identified: CREBBP-SRGAP2B, DNAH14-IKZF1, ETV6-SNUPN, ETV6-NUFIP1. Although a fusion gene is not sufficient to cause leukemia, it could be involved in the pathogenesis of the disease. Notably, these new translocations were found in genes encoding for hematopoietic transcription factors which are known to play an important role in leukemogenesis and disease prognosis such as IKZF1, CREBBP, and ETV6. In addition, they may have an impact on the prognosis of Mexican pediatric patients with ALL, with the potential to be included in the current risk stratification schemes or used as therapeutic targets.

Caracterización del gen de fusión RUNX1-RUNX1T1 en pacientes cubanos con leucemia mieloide aguda, 2000-2016 / Characterization of RUNX1-RUNX1T1 fusion gene in Cuban patients with acute myeloid leukemia, 2000-2016

Introducción: el gen de fusión RUNX1-RUNX1T codifica para una proteína quimérica con múltiples efectos en la proliferación, diferenciación y viabilidad de las células leucémicas. Objetivo: describir el comportamiento del RUNX1-RUNX1T1 en pacientes cubanos con dicha enfermedad. Método: Para ello se estudió el gen de fusión RUNX1-RUNX1T1 en 251 pacientes con leucemia mieloide aguda, mediante la reacción en cadena de la polimerasa, en el Instituto de Hematología e Inmunología de La Habana, entre los años 2000 y 2016. Resultados: El 20,3 por ciento (51 pacientes) fue positivo para el gen de fusión RUNX1-RUNX1T1, con una edad comprendida entre los 11 meses y los 80 años, media de 26 años. En los pacientes pediátricos la frecuencia del transcrito fue casi el doble de la de los adultos (29,2 por ciento y 15,3 por ciento, respectivamente) (p= 0,009). Mayor cantidad de pacientes masculinos presentaron el gen quimérico. En menores de 25 años hubo una mayor frecuencia del transcrito (p=0,019) con predominio significativo de la mutación en los adolescentes (p=0,027). Cinco pacientes fueron positivos al RUNX1-RUNX1T1 y a la duplicación interna en tándem del gen FLT3 (12,2 por ciento). Ningún paciente positivo al RUNX1-RUNX1T1 presentó el gen de fusión CBFB-MYH11. La mayor asociación estuvo con la mutación A del gen NPM1 para un 25 por ciento. El debut de la enfermedad se caracterizó por anemia moderada (p= 0,024), trombocitopenia severa (p= 0,004) y gran infiltración medular. La mayor discrepancia entre diagnósticos se concentró entre las variantes morfológicas M2 y M3 (p= 0,000). Conclusiones: En pacientes cubanos la leucemia mieloide aguda con gen de fusión RUNX1-RUNX1T1 positivo, tiene un comportamiento similar a lo descrito internacionalmente con algunas particularidadesen las características hematológicas de presentación de la enfermedad. El estudio molecular es imprescindible para definir el diagnóstico, y la estrategia terapéutica en estos pacientes(AU)

Introduction: The RUNX1-RUNX1T fusion gene codes for a chimeric protein with multiple effects on the proliferation, differentiation and viability of leukemic cells. Objective: To describe the behavior of RUNX1-RUNX1T1 in Cuban patients with this disease. Method: The RUNX1-RUNX1T1 fusion gene was studied in 251 patients with acute myeloid leukemia, through the polymerase chain reaction, at the Institute of Hematology and Immunology of Havana, between 2000 and 2016. Results: The 20.3 percent (51 patients) were positive for the RUNX1-RUNX1T1 fusion gene, with an age between 11 months and 80 years, average of 26 years.In pediatric patients, the transcript frequency was almost twice that of adults (29.2 percent and 15.3 percent , respectively) (p= 0.009). More male patients presented the chimeric gene. There was a higher frequency of the transcript in children under 25 years of age (p= 0.019) with a significant predominance of the mutation in adolescents (p= 0.027).Five patients were positive for RUNX1-RUNX1T1 and for internal tandem duplication of the FLT3 gene (12.2 percent ).No patient positive for RUNX1-RUNX1T1 presented the CBFB-MYH11 fusion gene. The greatest association was with the A mutation of the NPM1 gene for 25 percent . The onset of the disease was characterized by moderate anemia (p= 0.024), severe thrombocytopenia (p= 0.004) and extensive bone marrow infiltration. The greatest discrepancy between diagnoses was concentrated between the morphological variants M2 and M3 (p= 0.000). Conclusions: In Cuban patients, acute myeloid leukemia with a positive RUNX1-RUNX1T1 fusion gene has a behavior similar to that described internationally with some peculiarities in the hematological characteristics of the disease presentation.The molecular study is essential to define the diagnosis, and the therapeutic strategy in these patients(AU)

Pathotyping and Phylogenetic Characterization of Newcastle Disease Viruses Isolated in Peru: Defining Two Novel Subgenotypes Within Genotype XII.

Infections of poultry with virulent strains of avian paramyxovirus 1 (APMV-1), also known as Newcastle disease viruses (NDVs), cause Newcastle disease (ND). This highly contagious disease affects poultry and many other species of birds worldwide. In countries where the disease is prevalent, constant monitoring and characterization of isolates causing outbreaks are necessary. In this study, we report the results of pathogenicity testing and phylogenetic analyses of seven NDVs isolated from several regions of Peru between 2004 and 2015. Six viruses had intracerebral pathogenicity indices (ICPIs) of between 1.75 and 1.88, corresponding to a velogenic pathotype. The remaining virus had an ICPI of 0.00, corresponding to a lentogenic pathotype. These results were consistent with amino acid sequences at the fusion protein (F) cleavage site. All velogenic isolates had the polybasic amino acid sequence 112RRQKR↓F117 at the F cleavage site. Phylogenetic analyses of complete F gene sequences showed that all isolates are classified in class II of APMV-1. The velogenic viruses are classified in genotype XII, while the lentogenic virus is classified in genotype II, closely related to the LaSota vaccine strain. Moreover, tree topology, bootstrap values, and genetic distances observed within genotype XII resulted in the identification of novel subgenotypes XIIa (in South America) and XIIb (in China) and possibly two clades within genotype XIIa. All velogenic Peruvian viruses belonged to subgenotype XIIa. Overall, our results confirm the presence of genotype XII in Peru and suggest that it is the prevalent genotype currently circulating in our country. The phylogenetic characterization of these isolates helps to characterize the evolution of NDV and may help with the development of vaccines specific to our regional necessities.

Attomolar electrochemical detection of the BCR/ABL fusion gene based on an amplifying self-signal metal nanoparticle-conducting polymer hybrid composite.

In the last ten years, conjugated polymers started to be used in the immobilization of nucleic acids via non-covalent interactions. In the present study, we describe the construction and use of an electrochemical DNA biosensor based on a nanostructured polyaniline-gold composite, specifically developed for the detection of the BCR/ABL chimeric oncogene. This chromosome translocation is used as a biomarker to confirm the clinical diagnosis of both chronic myelogenous leukemia (CML) and acute lymphocytic leukemia (ALL). The working principle of the biosensor rests on measuring the conductivity resulting from the non-covalent interactions between the hybrid nanocomposite and the DNA probe. The nanostructured platform exhibits a large surface area that enhances the conductivity. Positive cases, which result from the hybridization between DNA probe and targeted gene, induce changes in the amperometric current and in the charge transfer resistance (RCT) responses. Atomic force microscopy (AFM) images showed changes in the genosensor surface after exposure to cDNA sample of patient with leukemia, evidencing the hybridization process. This new hybrid sensing-platform displayed high specificity and selectivity, and its detection limit is estimated to be as low as 69.4 aM. The biosensor showed excellent analytical performance for the detection of the BCR/ABL oncogene in clinical samples of patients with leukemia. Hence, this electrochemical sensor appears as a simple and attractive tool for the molecular diagnosis of the BCR/ABL oncogene even in early-stage cases of leukemia and for the monitoring of minimum levels of residual disease.

Pulmonary extraskeletal myxoid chondrosarcoma: A case report and literature review.

BACKGROUND: Extraskeletal myxoid chondrosarcoma (EMC) accounts for the 3% of all soft tissue sarcomas and it's categorized as a tumour of uncertain differentiation. This entity has shown to have the recurrent balanced chromosomal translocation t(9;22) (q22;q12.2), which leads to the oncogenic fusion gene EWSR1-NR4A3. This sarcoma usually presents as a slow growing, palpable mass in the extremities. EMC arising from the lung is extremely infrequent. We report one case of pulmonary extraskeletal mixoid chondrosarcoma and a review of the world literature. CASE REPORT: A 69-year-old male patient presented with intermittent hemoptysis for the last 6 months. A PET/CT scan showed a hypermetabolic solid mass with lobulated borders of approximately 29×26mm in the inferior right lobe. We performed a right thoracotomy with inferior lobectomy and lymphadenectomy of levels VII, VIII, X, and XI levels. The neoplasm was constituted by cords of small cells with small round nucleus and scarce cytoplasm immerse in an abundant myxoid matrix. The immunophenotype was positive for MUM-1, CDK4, MDM2, and showed focal expression for S-100 protein and CD56. The final pathology report revealed a pulmonary extraskeletal mixoid chondrosarcoma. No further surgical interventions or adjuvant therapies were needed. CONCLUSION: EMC is an intermediate-grade neoplasm, characterized by a long clinical course with high potential for local recurrence and distant metastasis. Treatment for EMC is surgical and non-surgical treatment is reserved for recurrence or metastatic disease. Pulmonary extraskeletal myxoid chondrosarcoma is a rare neoplasm with only isolated case reports found in the literature.

Patrones de hibridación del gen de fusión BCR/ABL1 en pacientes cubanos con leucemia / Hybridization patterns of BCR / ABL1 gen in cuban patients with leukemia

Introducción: la leucemia mieloide crónica (LMC) se caracteriza por la presencia de la translocación t(9,22) que resulta en la formación del gen de fusión BCR/ABL1. En ocasiones esta alteración genética puede asociarse con deleciones en secuencias del cromosoma 9 derivativo y otras variantes que no se observan con la citogenética convencional, pero pueden ser detectadas mediante la técnica de hibridación in situ por fluorescencia (FISH). Objetivo: describir los patrones de hibridación en pacientes positivos a la t(9;22) a partir de la introducción de la técnica de FISH para el estudio de las leucemias en Cuba. Métodos: se estudiaron muestras de sangre medular de 36 pacientes con LMC y ocho con leucemia linfoblástica aguda (LLA), en el Instituto de Hematología e Inmunología. Se empleó la sonda LSI BCR/ABL1 Dual Color Dual Fusion. Resultados: entre los pacientes con LMC, dos muestras resultaron no útiles para el diagnóstico y 18 fueron positivas para el BCR-ABL1, una de ellas mostró un patrón de hibridación atípico. Todas las muestras de pacientes con LLA resultaron negativas. En un paciente con impresión diagnóstica de LMC BCR-ABL1 negativo, se observó un patrón de señales que sugiere trisomía del cromosoma 9. Conclusiones: la incorporación de la técnica de FISH para el estudio del transcripto BCR/ABL1 en pacientes con LMC y LLA permitió detectar su presencia y la existencia de patrones de señales atípicos, los que pudieran no ser detectables mediante la citogenética convencional y tener significación pronóstica(AU)

Introduction: Chronic myeloid leukemia (CML) is characterized by the t(9;22) translocation resulting in the formation of BCR/ABL1 fusion gen. Sometimes this genetic alteration can be associated to deletions in sequences of derivative chromosome 9 and other variants detected by fluorescence in situ hybridization (FISH) technique. Objective: To describe hybridization patterns in patients positive to t(9;22) after the introduction of FISH at the leukemia study in Cuba. Methods: The bone marrow samples of 36 patients with diagnosis of CML and eight patients with acute lymphoblastic leukemia (ALL) were studied at the Cytogenetics Laboratory of the Institute of Hematology and Immunology. The BCR/ABL Dual Color Dual Fusion probe was used. Results: The sample of two CML patients were non-useful for diagnosis and 18 were t(9;22) positive, one with an atypical pattern of signals. All the ALL patients were negative. In one negative CML patient was observed a pattern of signals suggestive of trisomy 9. Conclusions: Incorporation of FISH for the BCR/ABL1 transcript study in CML and ALL patients allowed us to detect its presence and the existence of different patterns of signals which could be no detectable by conventional cytogenetic and could have prognostic significance(AU)

Runx1-Runx1t1: comportamiento en pacientes con leucemia mieloide aguda en nuestro medio / Runx1-Runx1t1: behavior in patients with acute myeloid leukemia

El continuo desarrollo molecular ha restado protagonismo a otras clasificaciones de la leucemia mieloide aguda (LMA) basadas en la morfología e histoquímica general. En el caso de la LMA existe un subtipo donde el gen AML1 (RUNX1), esencial para la normal hematopoyesis, se fusiona con el gen co-represor transcripcional ETO (RUNX1T1) generando una proteína anormal con múltiples efectos en la mielopoyesis. Se analizó el comportamiento de este gen de fusión en 174 pacientes con LMA, estudiados por reacción en cadena de la polimerasa con reverso transcripción (RT-PCR) en el laboratorio de Biología Molecular del Instituto de Hematología e Inmunología (IHI) entre enero del 2000 y agosto del 2013. El 13,8 por ciento (24 pacientes) fue positivo al RUNX1-RUNX1T1. En dicho grupo la edad osciló entre los 3 y los 62 años, con una media de 20,9 años aunque la mayor incidencia fue en pacientes de edad pediátrica (1-19 años) con un 66,7 por ciento Predominó el sexo masculino y el color de la piel no blanca con 62,5 por ciento y 58,3 por ciento respectivamente. De estos pacientes, el 37,5 por ciento presentaron un diagnóstico morfológico de M2, el 12,5 por ciento de M4 y la mitad de los casos 50 por ciento habían tenido un diagnóstico al debut, sugestivo de leucemia promielocítica (LPM); a este último grupo se le determinó la presencia del gen quimérico PML/RARα, para los que fueron negativos, demostrándose posteriormente el RUNX1-RUNX1T1. En un solo paciente se encontró la asociación de la duplicación interna en tándem (DIT) del FLT3 con el RUNK1-RUNX1T1. La confirmación de la presencia del gen de fusión RUNX1-RUNX1T1 en pacientes con morfología M3, confirma una vez más que las técnicas moleculares son de vitales para el diagnóstico de la LMA y la morfología se va relegando a los casos donde la citogenética y la biología molecular a día de hoy no logren definir una alteración genética. Introducción: el continuo desarrollo molecular ha restado protagonismo a otras clasificaciones de la leucemia mieloide aguda (LMA) basadas en la morfología e histoquímica general. En el caso de la LMA existe un subtipo donde el gen AML1 (RUNX1), esencial para la hematopoyesis normal, se fusiona con el gen correpresor transcripcional ETO (RUNX1T1) nó el sexo masculino (62,5 por cientoy el color de la piel no blanca (58,3 por ciento). El 37,5 por ciento de los pacientes presentó diagnóstico morfológico de M2, el 12,5 por ciento de M4, y el 50 por ciento había tenido un diagnóstico al debut sugestivo de leucemia promielocítica; posteriormente se demostró el RUNX1 - RUNX1T1. En el 8,3 por ciento de los pacientes positivos al RUNX1 - RUNX1T1 se encontró asociación con la duplicación interna en tándem (DIT) del FLT3. Conclusiones: la presencia del gen de fusión RUNX1-RUNX1T1 en pacientes con morfología M3, confirma una vez más que las técnicas moleculares son de vital importancia para el diagnóstico de la LMA y la morfología se va relegando a los casos donde la citogenética y la biología molecular no logren definir una alteración genética(AU)

Introduction: the molecular development has reduced importance to other classifications of acute myeloid leukemia (AML) based on morphology and general histochemistry. When AML1 (RUNX1) gene, essential for normal hematopoiesis, is fused to the transcriptional co-repressor ETO (RUNX1T1) gene, an abnormal protein with multiple effects on myelopoiesis is synthesized. Objective: analyze the behavior of the fusion gene RUNX1 - RUNX1T1 in our patients. Methods: this fusion gene was evaluated in 174 patients with AML studied by polymerase chain reaction with reverse transcription (RT - PCR) at the laboratory of Molecular Biology of the Institute of Hematology and Immunology (IHI), between January 2002 and August 2013. Results: twenty four patients (13,8 percent) were positive to RUNX1-RUNX1T1. In this group age ranged from 3 to 62 years with a mean of 20.9 years, although the incidence was higher in pediatric patients (1 - 19 years), 66,7 percent. Males and non-white individuals were predominant with 62,5 percent and 58,3 percent respectively. Of these patients, 37,5 percent had a morphological diagnosis of AML M2; 12,5 percent of M4; and half of the patients (50 percent) had a diagnosis suggestive of promyelocytic leukemia (PML). In the latter group, the presence of the chimeric gene PML / RARα was determined; all these patients were negative for this fusion gene and later the RUNX1 - RUNX1T1 was demonstrated. The association of internal tandem duplication (ITD) - FLT3 with RUNK1 - RUNX1T1 was found in 8,3 percent. Conclusions: the fusion gene RUNX1 - RUNX1T1 in patients with morphological appearance of M3, once again confirms that molecular techniques are vital for the diagnosis of AML and morphology is relegated to cases where cytogenetic and molecular biology fails to define a genetic alteration(AU)

Gen de fusión AML-1/ETO y mutación NPM-1A en leucemia mieloide crónica en crisis blástica mieloide / AML-1/ETO fusion gene and mutation NPM-1A in myeloid chronic leukemia in myeloid blast crisis

La leucemia mieloide crónica es una neoplasia mieloproliferativa de naturaleza clonal que generalmente y de manera progresiva transita por tres fases: crónica, acelerada y crisis blástica. Alrededor del 80 por ciento de los enfermos con leucemia mieloide crónica son diagnosticados durante la fase crónica, 10 por ciento en fase acelerada y otro 10 por ciento durante la crisis blástica. A la presencia del cromosoma Filadelfia y la formación del gen de fusión BCR/ABL, que se traduce en la proteína quimérica pBCR/ABL, le sigue una gran inestabilidad genómica y la adquisición de alteraciones cromosómicas y moleculares adicionales. Algunas alteraciones moleculares, que suelen estar presentes en otras hemopatías malignas, pueden ser adquiridas durante la progresión de la leucemia mieloide crónica a crisis blástica. Se presenta el caso de un paciente que debutó con una leucemia mieloide crónica en crisis blástica, con positividad del gen de fusión BCR/ABL, el gen de fusión AML-1/ETO y la mutación NPM-1A(AU)

Chronic myeloid leukemia is a clonal myeloproliferative neoplasm which generally and progressively goes through three phases: chronic, accelerated and blast crisis. About 80 percent of patients with chronic myeloid leukemia are diagnosed in chronic phase, 10 % in accelerated phase and 10 percent in blast crisis. The presence of Philadelphia chromosome and the formation of BCR/ABL fusion gene, resulting in the chimeric protein pBCR/ABL, generates a large genomic instability and the acquisition of additional chromosomal and molecular alterations. Some molecular alterations, which are usually present in other hematological malignancies, could be acquired during the progression of chronic myeloid leukemia to blast crisis. This report presents the case of a patient with de novo chronic myeloid leukemia in blast crisis, with positivity of BCR/ABL fusion gene, AML-1/ETO fusion gene and mutation NPM-1A(AU)