¿Es importante conocer el tipo de transcripto BCR-ABL en la leucemia mieloide crónica? / Is it important to know the type of BCR-ABL transcript in chronic myeloid leukemia?

La leucemia mieloide crónica se caracteriza por la ocurrencia de una translocación recíproca entre los cromosomas 9 y 22; que da origen a un cromosoma 22 derivativo conocido como Filadelfia. En el sitio de unión se forma el gen de fusión BCR-ABL que conlleva a la síntesis de una proteína híbridacon propiedades oncogénicas. El sitio de unión entre los cromosomas 9 y 22 es variable y da lugar a transcritos diferentes; los conocidos como e13a2 y e14a2 son los más frecuentes y estudiados. El análisis de las características clínico-hematológicas de presentación y la respuesta al tratamiento entre los pacientes portadores de e13a2 o e14a2 ha revelado diferencias que pueden ser útiles para la predicción del pronóstico. Se realizó una revisión de la literatura científica a través de PUBMED. Se analizó y resumió la información. Se evidencian diferentes características de presentación, pero no existe coincidencia entre todos los autores. Respecto al comportamiento de la respuesta al tratamiento con inhibidores de tirosina quinasa, algunos autores encuentran diferencias y algunos sugieren que puede tratarse de dos enfermedades diferentes. Puede ser importante conocer el tipo de transcripto BCR-ABL en la LMC ya que, al menos entre los dos más frecuentes, existen diferencias que pueden ser útiles en la predicción del pronóstico para el paciente, así como para el manejo del tratamiento(AU)

Chronic myeloid leukemia is characterized by the occurrence of a reciprocal translocation between chromosomes 9 and 22; which gives rise to a derivative chromosome 22 known as Philadelphia. At the binding site, the BCR-ABL fusion gene is formed, which leads to the synthesis of a hybrid protein with oncogenic properties. The binding site between chromosomes 9 and 22 is variable and gives rise to different transcripts; those known as e13a2 and e14a2 are the most frequent and studied. The analysis of the clinical-hematological characteristics of presentation and the response to treatment among patients with e13a2 or e14a2 has revealed differences that may be useful for the prediction of prognosis. To describe the different characteristics reported for one or another transcript and to know if it is important to know the type of transcript in the CML. A review of the scientific literature was carried out through PUBMED. The information was analyzed and summarized. Different presentation characteristics are evident but there is no coincidence between all the authors. Regarding the behavior of the response to treatment with tyrosine kinase inhibitors, some authors find differences and some suggest that it may be two different entities. It may be important to know the type of BCR-ABL transcript in CML cause, at least between the two most frequent, there are differences that may be useful in predicting the prognosis for the patient as well as for the management of treatment(AU)

Respuesta molecular profunda con ponatinib en leucemia mieloide crónica en fase crónica con resistencia a imatinib y dasatinib: Reporte de caso y revisión de la literatura / Profound molecular response with ponatinib in chronic phase of chronic myeloid leukemia with resistance to imatinib and dasatinib: Case report and review of the literature

RESUMEN Se reporta el caso de una mujer quien a la edad de 54 años fue diagnosticada de leucemia mieloide crónica en fase crónica; inició tratamiento con inhibidor de tirosina cinasa de primera generación, y evidenció falla por ausencia de respuesta hematológica y citogenética. A pesar del cambio de tratamiento a un inhibidor de tirosina cinasa de segunda generación (dasatinib), no fue posible alcanzar niveles óptimos de respuesta, documentándose la positividad para la mutación T315I en dominio ABL de la tirosina cinasa desregulada BCR/ABL, frente a la cual el único medicamento que muestra actividad es ponatinib. Luego de iniciar tratamiento con ponatinib, se evidenciaron niveles óptimos de respuesta citogenética y molecular, así como una adecuada calidad de vida de la paciente.

SUMMARY We report the case of a woman who at the age of 54 years was diagnosed with chronic myeloid leukemia in chronic phase; she began treatment with a first-generation tyrosine kinase inhibitor, and evidenced failure due to the absence of a hematological and cytogenetic response. Despite changing treatment to a second-generation tyrosine kinase inhibitor (dasatinib), it was not possible to achieve optimal levels of response, documenting positivity for the T315I mutation in the ABL domain of the deregulated BCR/ABL tyrosine kinase, compared to ponatinib, the only drug that shows activity. After starting treatment with ponatinib, optimal levels of cytogenetic and molecular response were evidenced, as well as an adequate quality of life for the patient.

Quimioterapia intensiva asociada a imatinib en leucemia linfoblástica aguda del adulto, Philadelphia positivo. Experiencia en un hospital público / Intensive chemotherapy with tyrosine kinase inhibitors in philadelphia-positive acute lymphoblastic leukemia

Background: Before the advent of tyrosine kinase inhibitors (TKIs), patients with Philadelphia-positive Acute Lymphoblastic Leukemia (Ph+ALL) had a poor prognosis. The association of TKIs to intensive chemotherapy (CT) improved outcome. Aim: To evaluate results of an intensive CT protocol including TKI in a public hospital in Santiago, Chile. Material and Methods: All patients with Ph+ALL diagnosed between January 2010 and February 2019, and who met inclusion criteria for intensive CT, received the Ph+ALL national protocol in association with imatinib and were included in this analysis. Results: Thirty-five patients aged 15 to 59 years received treatment. Complete response (CR) was obtained in 97%. Measurable residual disease (MRD) was negative in 61% (19/31 evaluable cases) during follow-up, and 55% (16/29) were MRD (-) before three months. Relapse was observed in 13 cases. Three patients underwent allogeneic hematopoietic stem cell transplant (HSCT), two in CR1. The overall survival (OS) and event-free survival (EFS) at three years were 52 and 34%, respectively. In patients who achieved MRD negativity before three months, no statistically significant differences in OS (64 and 42% respectively, p = 0.15) or EFS (35 and 32% respectively, p = 0.37) were observed. Conclusions: The prognosis of Ph+ALL improved with the association of imatinib to intensive CT. MRD-negative status before three months in this series was not significantly associated with better outcomes. Our series suggests that the Ph+ALL national protocol associated to TKI is a therapeutic alternative with high CR and aceptable MRD (-) rates.

Prognostic significance of a normal karyotype in adult patients with BCR-ABL1-positive acute lymphoblastic leukemia in the tyrosine kinase inhibitor era

OBJECTIVE: The occurrence of cryptic Philadelphia (Ph) chromosome translocation is rare in BCR-ABL1-positive acute lymphoblastic leukemia (BCR-ABL1+ ALL) and is of unknown significance in the tyrosine kinase inhibitor (TKI) era. METHODS: We retrospectively studied a series of adult patients receiving TKI-based therapy to evaluate the prognostic impact of the normal karyotype (NK) (n=22) in BCR-ABL1+ ALL by comparison with the isolated Ph+ karyotype (n=54). RESULTS: There were no statistically significant differences in clinical characteristics and complete remission rate between the two groups. Compared with the isolated Ph+ group, the NK/BCR-ABL1+ group had a higher relapse rate (55.0% versus 29.4%, p=0.044). Overall survival (OS) and disease-free survival (DFS) were significantly shorter in the NK/BCR-ABL1+ group than in the isolated Ph+ group [median OS: 24.5 versus 48.6 (months), p=0.013; median DFS: 11.0 (months) versus undefined, p=0.008]. The five-year OS and DFS for patients with NK/BCR-ABL1+ were 19.2% and 14.5%, respectively; those for patients with isolated Ph+ were 49.5% and 55.7%, respectively. Thirty-four (44.7%) patients underwent allogeneic hematopoietic stem cell transplantation (allo-HSCT) in this study. Among the patients who received allo-HSCT, the median OS and DFS in the NK/BCR-ABL+ group (n=9) were 35.5 and 27.5 months, respectively, while those in the isolated Ph+ group (n=25) were undefined. There was a trend of significant statistical difference in the OS between the two subgroups (p=0.066), but no significant difference in the DFS. Multivariate analysis revealed that NK was independently associated with worse OS and DFS in BCR-ABL1+ ALL patients [Hazard ratio (HR) 2.256 (95% confidence interval (CI), 1.005-5.066), p=0.049; HR 2.711 (95% CI, 1.319-5.573), p=0.007]. CONCLUSION: Our results suggest that the sub-classification of an NK could be applied in the prognostic assessments of BCR-ABL1+ ALL. In addition, allo-HSCT should be actively performed to improve prognosis in these patients.

Isocromosoma Filadelfia en dos pacientes con leucemia mieloide crónica / Philadelphia isochromosome in two patients with chronic myeloid leukemia

RESUMEN El cromosoma Filadelfia (Ph por su abreviatura del inglés "Philadelphia") se presenta en más del 90 % de los pacientes con leucemia mieloide crónica. Un cromosoma Ph extra es una de las alteraciones secundarias comúnmente observada como evolución clonal de la enfermedad y se puede presentar como un derivativo adicional o un isocromosoma del 22 derivativo. Es una alteración adquirida durante la progresión de la enfermedad con implicación pronóstica. Se presentan dos casos con diagnóstico de leucemia mieloide crónica, resistentes al tratamiento con mesilato de imatinib. En el estudio cromosómico con técnica de banda G se observaron en ambos pacientes líneas celulares con dos isocromosomas del derivativo del 22, 2ider (22) t (9; 22). El primer caso falleció en crisis blástica y el segundo luego de no responder al tratamiento de primera línea, se le indicó nilotinib pero su evolución fue no satisfactoria. Las alteraciones cromosómicas secundarias están asociadas con un impacto negativo en la supervivencia y progresión a fase acelerada y crisis blástica de la enfermedad.

ABSTRACT The Philadelphia chromosome (Ph) is present in more than 90% of patients with chronic myeloid leukemia. An extra Ph chromosome is one of the secondary alterations commonly observed in clonal evolution and it could be as na additional derivative or anisochromosome of the derivative. It is na alteration acquired during the progression of the disease with prognostic implications. We present two cases with a diagnosis of chronic myeloid leukemia, Who showed resistance to treatment with imatinib mesylate. In both patients,the chromosomal study with G-band technique, show cell lines with two isochromosomes from the derivative of 22, 2ider(22)t(9; 22). The first case died in blast crisis and to the second after not responding to the first line treatment, was precribed nilotinib but the evolution was unsatisfactory. Secondary chromosomal alterations are associated with a negative impact on survival and the progression to accelerated phase and blast crisis of the disease.

Caracterización biológica del marcador CD66c y su importancia clínica en la leucemia linfoide aguda / Biological characterization of the CD66c marker and its clinical importance in acute lymphoid leukemia

Las leucemias son un grupo heterogéneo de hemopatías con diversa etiología, patogenia, historia natural y pronóstico en las que se desencadena una proliferación clonal. La leucemia linfoblástica aguda (LLA) es el tipo de cáncer más común en los niños, se caracteriza por la infiltración de células neoplásicas del sistema hematopoyético a la médula ósea, sangre y otros tejidos. Fue considerada fatal hasta hace 30 años, hoy, la tasa de sobrevida a los 5 años supera el 70 por ciento, lo que implica que la mayoría de los pacientes puede curarse; sin embargo, la situación es diferente para la población infantil de los países en desarrollo. Se estima que la supervivencia al cáncer es entre 10 y 20 por ciento menor que para los infantes en países desarrollados. Uno de los marcadores de inmunofenotipo que ha cobrado mayor relevancia en los últimos años en el diagnóstico de LLA-B y seguimiento de la enfermedad mínima residual es el CD66c, este es una glicoproteína miembro de la familia del antígeno carcinoembrionario con función de adhesión celular y ampliamente utilizado como marcador tumoral que fue descubierto por SvenBerg a finales de los años 1970. Este antígeno se expresa en la superficie de los granulocitos y está implicado en varias funcionesbiológicas, que incluyen la adhesión celular, la migración, la transducción de señales y la regulación de la expresión génica. Este antígeno se presenta frecuentemente en varios tipos de cáncer y su sobrexpresión se asocia a menudo con pobre respuesta al tratamiento y disminución de la supervivencia de los pacientes. Diversos estudios evidencian que este marcador se relaciona con la presencia de diversas alteraciones cromosómicas como BCR-ABL, CRLF2, hiperdiploidía, que permiten orientar al pronóstico de la enfermedad(AU)

Leukemias are a heterogeneous group of blood diseases with a diverse etiology, pathogenesis, natural history and prognosis in which a clonal proliferation may be triggered. Acute lymphoid leukemia (ALL) is one of the most common types of cancer in children, it is characterized by the infiltration of neoplastic cells from the haematopoietic system to the bone marrow, blood and other tissues. Until 30 years ago, it was considered fatal; nowadays, the five-year survival rate exceeds 70 percent, which implies that most patients may heal. Nevertheless, in developing countries the situation might be different for pediatric population; it is estimated that cancer survival rate ranges between 10 and 20 percent less than those children living in developed countries. One of the immunophenotype markers that has been relevant in the last few years in the diagnosis of B-ALL and the follow-up of the minimal residual disease is CD66c. This is a member of the glycoprotein family from the carcinoembryonic antigen with a cellular adhesion function that has been widely used as a tumor marker as discovered by Sven Berg in the late 1970's. This antigen has been identified as a superficial protein expressed on the granulocytes and it is also involved in several biological functions, including cellular adhesion, migration, signal transduction and regulation of gene expression. This antigen is frequently presented in several types of cancer and its overexpression is often associated with a poor response to treatment and a decrease of survival rates for patients. Several studies have evidenced that this marker is relatedwith the presence of several chromosomal abnormalities, such as: BCR-ABL, CRLF2, and hyperdiploidy, which may help in the disease prognosis(AU)

The role of cytogenetics and molecular biology in the diagnosis, treatment and monitoring of patients with chronic myeloid leukemia / O papel da citogenética e da biologia molecular no diagnóstico, no tratamento e no monitoramento de pacientes com leucemia mieloide crônica

ABSTRACT Chronic myeloid leukemia (CML) is the most common myeloproliferative disorder among chronic neoplasms. The history of this disease joins with the development of cytogenetic analysis techniques in human. CML was the first cancer to be associated with a recurrent chromosomal alteration, a reciprocal translocation between the long arms of chromosomes 9 and 22 - Philadelphia chromosome. This work is an updated review on CML, which highlights the importance of cytogenetics analysis in the continuous monitoring and therapeutic orientation of this disease. The search for scientific articles was carried out in the PubMed electronic database, using the descriptors "leukemia", "chronic myeloid leukemia", "treatment", "diagnosis", "karyotype" and "cytogenetics". Specialized books and websites were also included. Detailed cytogenetic and molecular monitoring can assist in choosing the most effective drug for each patient, optimizing the treatment. Cytogenetics plays a key role in the detection of chromosomal abnormalities associated with malignancies, as well as the characterization of new alterations that allow more research and increase knowledge about the genetic aspects of these diseases. The development of new drugs, through the understanding of the molecular mechanisms involved, will allow a possible improvement in the survival of these patients.

RESUMO Leucemia mieloide crônica (LMC) é a desordem mieloproliferativa mais comum entre as neoplasias crônicas. A história dessa doença se alia ao desenvolvimento de técnicas de análise citogenética em humanos. Foi o primeiro câncer a ser associado a uma alteração cromossômica recorrente, uma translocação recíproca entre os braços longos do cromossomo 9 e 22 - o cromossomo Philadelphia. Este trabalho é uma revisão atualizada sobre LMC, o qual destaca a importância da análise citogenética no monitoramento contínuo e na orientação terapêutica dessa doença. A pesquisa de artigos científicos foi realizada no banco de dados PubMed, usando os descritores "leucemia", "leucemia mieloide crônica", "tratamento", "diagnóstico", "cariótipo" e "citogenética". Livros e sites especializados também foram incluídos. O monitoramento citogenético e molecular detalhado pode auxiliar na escolha do medicamento mais efetivo para cada paciente, otimizando seu tratamento. A citogenética desempenha um papel fundamental na detecção de anormalidades cromossômicas associadas a malignidades, bem como na caracterização de novas alterações que permitem mais pesquisas e ampliação do conhecimento sobre os aspectos genéticos dessas doenças. O desenvolvimento de novas drogas, através da compreensão dos mecanismos moleculares envolvidos, permitirá uma possível melhora na sobrevida desses pacientes.

Análisis de metilación en pacientes con leucemia mieloide crónica en diferentes instituciones médicas de Medellín / Methylation analysis in patients with chronic myeloid leukemia in different medical institutions in Medellín

Fundamento: la leucemia mieloide crónica es una neoplasia mieloproliferativa crónica que se caracteriza por la presencia del cromosoma filadelfia. Para esta se ha diseñado como tratamiento los inhibidores de tirosin kinasa, que genera en los pacientes una respuesta hematológica, citogenética y molecular. Esta enfermedad se caracteriza por presentar tres fases clínicas que son producto de la acumulación de daños tanto genéticos representados por mutaciones puntuales y alteraciones en el cariotipo; y cambios epigenéticos en genes tales como ABL-1, OSCP1, PDLIM4, NPM2, ER y p15. Objetivo: describir los patrones de metilación de seis genes en pacientes con leucemia mieloide crónica en distintas fases de la enfermedad tratados con algún ITK´s o en su defecto con hidroxiurea en dos hospitales de Medellín. Métodos: se realizó un estudio analítico trasversal, en el que se recolectaron 34 muestras a conveniencia de pacientes con leucemia mieloide crónica. Para hacer el análisis de estas muestras se usó una PCR específica de metilación. Los datos analizados no se distribuyeron de forma normal, por lo que se realizaron pruebas no paramétricas como U de Man Whitney y test exacto de Fischer, con una significancia de 0,05. Resultados: se encontró diferencias de estadísticas significativas en los datos del hemograma de ambas fases de la enfermedad, también se encontró una alta frecuencia de genes metilados en fase acelerada. La metilación de p15, ABL-1, ER son independiente de la fase de la enfermedad. En los pacientes tratados con hidroxiurea se observó una metilación del 100 % para los genes NPM2, OSCP1 y PDLIM4 este comportamiento no se observó en los individuos tratados con ITK´S, no obstante, para aquellos pacientes que desarrollaron resistencia a los ITK´s se observó un porcentaje de metilación mayor en los genes OSCP1, ABL-1 y PDLIM4. Conclusiones: la metilación en los genes PDLIM4 y OSCP1, puede asociarse con pronóstico desfavorable, ya que puede estar relacionado con la progresión de fase crónica a acelerada y el desarrollo de resistencia a los ITK´s.

Background: chronic myeloid leukemia (CML) is a chronic myeloproliferative neoplasm characterized by the presence of the Philadelphia chromosome. A specific treatment is designed as tyrosine kinase inhibitors (ITK's), which induces patients to have a hematologic, cytogenetic and molecular response. This disease is characterized by three clinical phases that result from the accumulation of genetic damage, both represented by point mutations and alterations in the karyotype; and epigenetic changes in genes such as ABL, OSCP1, PDLIM4, Npm2, ER and p15. Objective: to describe the schemes of six gens in patients with chronic myeloid leukemia in different stages of the disease and treated with some ITK in two hospitals in Medellín. Methods: a descriptive transversal study was conducted, in which 34 samples were collected at the convenience of patients with chronic myeloid leukemia (CML). To make the analysis of these samples methylation specific PCR was done. Results: statistical differences in blood count data from both phases of the disease was found, a high frequency of methylated genes in accelerated phase was also found. p15 methylation, ABL, ER are independent of the stage of the disease. In patients treated with hydroxyurea, methylation of 100 % for OSCP1 and PDLIM4 genes was observed and this behavior was not observed in individuals treated with ITK'S. In patients who developed resistance to ITK's however was observed a higher percentage of methylation in genes OSCP1 and PDLIM4. Conclusions: methylation in PDLIM4 and OSCP1 genes could be associated with poor prognosis possibly being associated with progression of chronic to accelerated phase and the development of resistance to ITK's.

Diversity of breakpoints of variant Philadelphia chromosomes in chronic myeloid leukemia in Brazilian patients

Background: Chronic myeloid leukemia is a myeloproliferative disorder characterized by the Philadelphia chromosome or t(9;22)(q34.1;q11.2), resulting in the break-point cluster regionAbelson tyrosine kinase fusion gene, which encodes a constitutively active tyrosine kinase protein. The Philadelphia chromosome is detected by karyotyping in around 90% of chronic myeloid leukemia patients, but 5-10% may have variant types. Variant Philadelphia chromosomes are characterized by the involvement of another chromosome in addition to chromosome 9 or 22. It can be a simple type of variant when one other chromosome is involved, or complex, in which two or more chromosomes take part in the translocation. Few studies have reported the incidence of variant Philadelphia chromosomes or the breakpoints involved among Brazilian chronic myeloid leukemia patients. Objective: The aim of this report is to describe the diversity of the variant Philadelphia chromosomes found and highlight some interesting breakpoint candidates for further studies. Methods: the Cytogenetics Section Database was searched for all cases with diagnoses of chronic myeloid leukemia during a 12-year period and all the variant Philadelphia chromosomes were listed. Results: Fifty (5.17%) cases out of 1071 Philadelphia-positive chronic myeloid leukemia were variants. The most frequently involved chromosome was 17, followed by chromosomes: 1, 20, 6, 11, 2, 10, 12 and 15. Conclusion: Among all the breakpoints seen in this survey, six had previously been described: 11p15, 14q32, 15q11.2, 16p13.1, 17p13 and 17q21. The fact that some regions get more fre- quently involved in such rare rearrangements calls attention to possible predisposition that should be further studied. Nevertheless, the pathological implication of these variants remains unclear. .

Evolución clonal en la leucemia mieloide crónica / Clonal evolution in chronic myeloid leukemia

Evolución clonal en la leucemia mieloide crónica se denomina a la presencia de alteraciones cromosómicas adicionales al cromosoma Filadelfia. Ocurre aproximadamente en el 30 por ciento de los pacientes en fase acelerada y en el 80 por ciento de los pacientes en crisis blástica. Es considerada un criterio de la fase acelerada de la enfermedad. Aunque se plantea que su presencia implica peor pronóstico, su significado es controversial y está en dependencia de la alteración citogenética específica, su frecuencia en el cariotipo, la asociación con otras alteraciones citogenéticas y clínicas de progresión, relación con el tiempo en que aparece en la evolución de la enfermedad y los tratamientos empleados

Clonal evolution in chronic myeloid leukemia is defined as the presence of a variety of additional, nonrandom chromosomal abnormalities besides the Philadelfia chromosome. It occurs in approximately 30 percent of patients in accelerated phase and 80 percent of patients in blastic phase. It is considered a criterion for accelerated phase. Although it is associated with a poor prognosis, its significance is controversial. It depends on the specific cytogenetic abnormality, its frequency in karyotype study, the association with other progression clinical and cytogenetic alterations, its relationship with the time of appearance during the course of the disease and the therapy used

Follow-up of the tumor load in patients with de novo chronic myeloid leukemia and in complete cytogenetic remission treated with imatinib in Colombia / Seguimiento de la carga tumoral en pacientes con leucemia mielode crónica de novo y en remisión citogenética completa tratados con imatinib en Colombia

ABSTRACT Objective: To evaluate the hematological, cytogenetic, and molecular responses in Colombian patients with CML chronic myeloid leukemia (CML) treated with imatinib. Methods: Two groups of patients, one with the novo diagnostic and another in state of complete cytogenetic remission were followed for 12 months with quantitative PCR evaluations every three months and with chromosomal analysis every 6 months. Results: The group with the novo diagnosis showed 50% of complete cytogenetic remission at 12 months while the other 50% were considered to have primary resistance. Respect the molecular analysis, 10.5% of the patients reached undetectable BCR-ABL transcripts at 12 months. In the complete cytogenetic remission group, 10.6% lost the state of complete cytogenetic remission at 12 months, 50% reached undetectable BCR-ABL transcripts but 10% showed levels higher than 10%, which in our standardization was equal to no molecular response. Conclusions: Despite having received the conventional dosages of 400 mg/day of imatinib, the cytogenetic and molecular responses obtained in our group of Colombian patients with CML, were lower than those in other international studies.

RESUMEN Objetivo. Evaluar las respuestas hematológica, citogenética y molecular en pacientes colombianos con leucemia mieloide crónica tratados con imatinib. Métodos. Dos grupos, uno con diagnóstico de novo y otro en el estado de remisión citogenética completa, se siguieron mediante estudios citogenéticos en médula ósea cada 6 meses y reacción en cadena de la polimerasa cuantitativa (Q-PCR) cada 3 meses. Resultados. En el grupo de novo, el 50% alcanzó el estado de remisión citogenética completa mientras el otro 50% se consideró con Resistencia primaria. Respecto al análisis molecular, 10.5% mostró transcriptos BCR-ABL indetectables. En el grupo de remisión citogenética completa, 10.6% perdió la condición de remisión citogenética completa, en el 50% los transcriptos BCR-ABL fueron indetectables mientras el 10% mostró niveles por encima del 10% considerado como no respuesta molecular, según nuestra estandarización. Conclusión. Aunque los pacientes recibieron las dosis convencionales de 400 mg/día de imatinib, las tasas de respuesta citogenética y molecular en los pacientes colombianos fueron menores que las obtenidas en estudios internacionales.

Philadelphia Brief Assessment of Cognition in healthy and clinical Brazilian sample / Avaliação Cognitiva Breve da Filadélfia numa amostra brasileira clínica e saudável

The Philadelphia Brief Assessment of Cognition (PBAC) is a neuropsychological screening instrument that assesses five cognitive domains: working memory, visuospatial functioning, language, episodic memory and comportment. The aim is to verify if PBAC can properly be used in the Brazilian sample. Participated in this study: (a) 200 healthy volunteers - 100 young [21.6(2.5) years old] and 100 older adults [70.1(7.3) years old]; >12 years of education; (b) 30 Alzheimer's patients (AD) [73.7(5.7) years old], 4-11 years in education. The PBAC scores: (a) 95.8(2.6), 90.0(4.4) and (b) 65.0(10.8) were correlated with the Mini-Mental State Examination (MMSE) for young 29.1(0.9), older adults 28.3(1.4) and AD 18.4(3.0) groups. A positive correlation between MMSE and PBAC (r=0.9, p<0.001) was found. Negative correlations were observed between PBAC domains [memory (-0.63), visuospatial abilities (-0.44) and working memory (-0.3) tasks]. MANOVA showed a better male performance in visuospatial functioning (F=8.5, p=0.004). The Brazilian version of PBAC proved to be a promising screening instrument for clinical purposes.

O instrumento de rastreio neuropsicológico Philadelphia Brief Assessment of Cognition (PBAC) avalia cinco domínios cognitivos: memória de trabalho, habilidade visuoespacial, linguagem, memória episódica e comportamento. O objetivo é verificar a viabilidade do PBAC em amostra brasileira. Participaram: (a) 200 voluntários - 100 jovens com 21,6(2,5) anos e 100 idosos com 70,1(7,3) anos, ambos com média de escolaridade maior que 12 anos; (b) 30 pacientes com Alzheimer, com 73,7(5,7) anos e escolaridade entre 4 e 11 anos. Os escores do PBAC para os respectivos grupos (a) 95,8(2,6), 90(4,4) e (b) 65(10,8) foram correlacionados com o Mini Exame do Estado Mental (MEEM). Houve correlação positiva (r=0,9; p<0,001) entre MEEM e PBAC, e negativas entre os domínios do PBAC [memória (-0,63), habilidades visuoespaciais (-0,44) e memória de trabalho (-0,3)]. Foi demonstrado pela MANOVA melhor desempenho no funcionamento visuoespacial em homens (F=8,5, p=0,004). A versão brasileira do PBAC provou ser promissora como um instrumento de rastreio para propósitos clínicos.

Association of HLA antigens and BCR-ABL transcripts in leukemia patients with the Philadelphia chromosome

OBJECTIVE: This study aimed to verify the association between human leukocyte antigens and the bcr-abl fusion protein resulting from t(9;22)(q34;q11) in chronic leukemia myeloid and acute lymphoblastic leukemia patients. METHODS: Forty-seven bcr-abl positive individuals were evaluated. Typing was performed bymicrolymphocytotoxicity and molecular biological methods (human leukocyte antigens Class I and Class II). A control group was obtained from the data of potential bone marrow donors registered in the Brazilian Bone Marrow Donor Registry (REDOME). RESULTS: Positive associations with HLA-A25 and HLA-B18 were found for the b2a2 transcript, as well as a tendency towards a positive association with HLA-B40 and a negative association with HLA-A68. The b3a2 transcript showed positive associations with HLA-B40 and HLA-DRB1*3. CONCLUSION: The negative association between human leukocyte antigens and the BCR-ABL transcript suggests that binding and presentation of peptides derived from the chimeric protein are effective to increase a cytotoxic T lymphocyte response appropriate for the destruction of leukemic cells.

Importância da adesão e monitorização terapêutica de imatinibe em pacientes portadores de LMC: revisão de estudos

A Leucemia Mielóide Crônica (LMC) é considerada uma desordem clonal das células precursoras hematopoéticas, caracterizada pela proliferação excessiva de células da série mielóide, associada a uma alteração citogenética específica conhecida por cromossomo “Philadelphia” (Ph). A LMC acomete ambos os sexos, com leve predomínio de doentes do sexo masculino. Pode ocorrer praticamente em todas as faixas etárias, tendo um pico de incidência entre a quarta e a sexta década de vida. Um número considerável de pacientes tem mostrado resistência ao Mesilato de Imatinibe, principal medicamento para o tratamento da LMC. Os fatores relacionados a esta resistência não são totalmente esclarecidos, mas entre os mais evidentes estão à baixa aderência ao tratamento. Em busca de dados publicados que evidenciam falhas na adesão ao Mesilato de Imatinibe, o presente trabalho reporta informações publicadas recentemente em estudos de revisão, ensaios clínicos e estudos observacionais. A base de dados PUBMED MEDLINE foi utilizada na busca de trabalhos publicados entre os anos de 2009 e abril de 2013. Seis artigos publicados no período citado e que estavam de acordo com o tema da revisão foram examinados e considerados. Todos os trabalhos analisados indicam que a adesão, bem como a monitarização são fundamentais para que o tratamento com Mesilato de Imatinibe seja bem sucedido. Quando considerados não aderentes, pacientes portadores de LMC mostram uma resposta clínica reduzida. Indicadores de baixa aderência e estratégias eficazes para melhorar taxas de adesão continuada necessitam de mais estudos. Os artigos utilizados nesta revisão de estudos mostram que fatores diversos contribuem para o sucesso terapêutico do Mesilato de Imatinibe. Uma avaliação contínua dos pacientes é uma ferramenta indispensável para a execução de estratégias que venham a contribuir para a melhora na aderência dos pacientes portadores de LMC.

Resultados citogéneticos en pacientes con leucemia mieloide crónica / Cytogenetic results in patients with chronic myeloid leukemia

Introducción: La leucemia mieloide crónica es una enfermedad mieloproliferativa caracterizada por 3 fases evolutivas. La evaluación citogenética de la enfermedad permite confirmar el diagnóstico y establecer el pronóstico. Objetivo: Reportar los resultados del estudio citogenético de 180 pacientes con diagnóstico clínico de leucemia mieloide crónica y correlacionarlos con las 3 fases de dicha neoplasia. Métodos: El análisis cromosómico de las muestras de médula ósea se realizó por las técnicas de bandas G y los cariotipos se clasificaron según los criterios del Sistema Internacional de Nomenclatura Cromosómica. Resultados: El 94 por ciento de los pacientes estudiados presentó la translocación t(9;22), que apareció con mayor frecuencia en los individuos en fase crónica (87,5 por ciento). En contraste, las anomalías cromosómicas secundarias al cromosoma Philadelphia resultaron las más frecuentes en los que estaban en fase acelerada y en crisis blástica (81,5 por ciento y 96 por ciento, respectivamente). Los resultados obtenidos confirman la relación que existe entre las alteraciones cromosómicas y las diferentes fases evolutivas de la leucemia mieloide crónica

Introduction: The chronic myeloid leukemia is a myeloproliferative disease characterized by three progressive phases. Its cytogenetic analysis assessment allows us to verify the diagnosis and to establish the prognosis. Objective: To report the cytogenetic results from 180 patients clinically diagnosed with chronic myeloid leukemia and correlate them with the three phases of such neoplasia. Methods: The chromosomal analysis of bone marrow samples was performed using the techniques of G bands and the karyotypes were classified according to the criteria of the International System of Chromosomal Nomenclature. Results: The 94 percent of study patients had the translocation t(9:22) more frequent in subjects in chronic phase (87,5 percent). In contrast, the chromosomal anomalies secondary to Philadelphia chromosome were the more frequent ones in those cases in accelerated phase and of blast crisis (81.5 percent and 96 percent), respectively. Results obtained confirm the relation existing among the chromosomal alterations and the different evolution phases of chronic myeloid leukemia

Leucemia meloide crónica: diagnóstico y tratamiento / Chronic myeloid leukemia: diagnosis and treatment

La Sociedad Americana de Cáncer estima que se diagnosticaron 5.050 nuevos casos de leucemia mieloide crónica (LMC) en Estados Unidos durante el 2009. Cerca de 470 personas en los Estados Unidos murieron a causa de la enfermedad en 2009, con un rango de edad de 45 a 55 años, y una razón hombre - mujer de 1,4:1. Este tipo de leucemias representa entre el 15-20% de todas las leucemias, con una incidencia de 1 a 2 casos por cada 100.000 adultos. Más del 50% de los pacientes con LMC serán asintomáticos al momento del diagnóstico y tendrán una esperanza de vida del 39% comparado con la población de adultos sanos. La LMC afecta principalmente a los adultos y se asocia a una anormalidad cromosómica llamada Cromosoma Filadelfia, el cual crea un gen anormal llamado BCR-ABL, que codifica una proteína anormal llamada tirosina kinasa, y se cree que ésto produce que las células afectadas por la leucemia crezcan y se desarrollen. La enfermedad presenta tres fases: crónica, acelerada y blástica. Cada una de estas fases difiere en su tiempo de duración, presentación clínica y respuesta al tratamiento. Tanto la fase acelerada, como la fase blástica son consideradas fases avanzadas, y el 15% de los pacientes con LMC se encontraran en una de estas fases en el momento de ser diagnosticados. El imatinib es el primer inhibidor sintético múltiple de tirosin-kinasa. La unión de este fármaco se logra en los sitios de unión de ATP, de la conformación BCR-ABL kinasa inactivos, logrando una inhibición del crecimiento e induciendo apoptosis de las células que expresan esta conformación. Un 20 a 30% de los pacientes a los que se les administra imatinib presentaran resistencia. El dasatinib® (BMS-354825) es la primera terapia autorizada por la FDA como tratamiento de la LMC resistente o intolerante a imatinib.

The American Cancer Society estimates that 5.050 new cases of chronic myeloid leukemia (CML) were diagnosed in United States in 2009. About 470 persons in the United States will die of chronic myeloid leukemia in 2009, with an age range going from 45 to 55, a mean from 53 to 55, with less than 10% under 20 years, with a male to female proportion of 1,4:1. This kind of leucemia represents between 15-20% of all leukemias, with an incidence of 1 to 2 cases per each 100,000 adults. More than 50% of the patients diagnosed with chronic myeloid leukemia will be asymptomatic at the time of the diagnosis and will have a life expectancy less than 39% if they compared to healthy adults. CML affects adults principally and it is associated to a chromosomal abnormality called the Philadelphia Chromosome, which generates an abnormal gene called BCR-ABL. This gene produces an abnormal protein called Tyrosine-Kinase, believed to cause growth and development in the cells affected by the leukemia. The disease has 3 phases: chronic, accelerated and blastic. Each phase has a differ different duration time, clinical presentation and response to treatment. The accelerated phase and blastic phase are considered advanced phases, and 15% of the total patients will have reached those phases at the time of the chronic mieloide leukemia diagnosis. Imanitib is the first multiple synthetic Tyrosine Kinase inhibitor. The union of this medication to the ATP binding sites of the inactive BCR-ABL Kinase conformation achieves the inhibition of the growth and induces apoptosis of the cells that express that conformation. Approximately 20 to 30% of the patients to whom Imatinib is administered will develop resistance. Dasatinib (BMS-354825) is the first therapy authorized by the FDA as a treatment of the CML which is resistant or intolerant to Imatinib.

Tratamiento con imatinib y el farmacogenotipo CYP3A4 en relación con la expansión clonal Ph(+) en leucemia mieloide crónica (LMC) / Imatinib treatment and pharmacogenotype CYP3A4 in relation with the clonal expansion Ph(+) in chronic myeloid leukemia (CML)

Introducción: imatinib es un inhibidor de la tirosina-kinasa BCR-ABL que revolucionó el tratamiento de pacientes con leucemia mieloide crónica (LMC) positivos para cromosoma Philadelphia (Ph+). Este medicamento se metaboliza principalmente por la enzima CYP3A4, cuyo gen presenta variaciones interindividuales tipo SNPs que pueden interferir con la efectividad del tratamiento, como son los polimorfismos CYP3A4*1B y CYP3A4*2 que han mostrado influencia significativa en la actividad metabólica de esta importante enzima farmacológica. Objetivos: Evaluar la frecuencia de polimorfismos de importancia farmacogenética en el gen CYP3A4 en una población de pacientes con LMC tratados con imatinib y en una población control de 164 personas. Correlacionar el genotipo con la evolución de la expansión clonal Ph(+) y la duración del tratamiento. Metodología: Genotipificación PCR-RFLP para los SNPs CYP3A4*1B y CYP3A4*2. Bandeo replicativo tipo RBHG para la evaluación citogenética de blastos espontßneos con o sin presencia del marcador Ph(+). Resultados: Los análisis citogenéticos revelaron una correlación directa entre el tiempo de tratamiento con imatinib y el porcentaje de reducción de blastos Philadelphia (+). Las genotipificaciones evidenciaron que la presencia del polimorfismo CYP3A4*1B no influye en la respuesta citogenética de los pacientes Ph+ tratados con imatinib, y que el polimorfismo fármaco relevante CYP3A4*2 estß ausente en esta población colombiana de controles y pacientes. Conclusiones: El farmacogenotipo CYP3A4*2 (exón 7) no afecta la respuesta citogenética positiva inducida por el imatinib en pacientes con LMC, en quienes la frecuencia de células Ph(+) por lo general se reduce en relación directa con la duración del tratamiento.

Introduction: Imatinib is an inhibitor of the BCR-ABL tyrosine-kinase that has dramatically changed the treatment of patient with Chronic myeloid leukemia (CML) positive for the Philadelphia chromosome (Ph+). This compound is mainly metabolized by the cytochrome CYP3A4 enzyme, coded by a gene with individual variations that could interfere with the effectiveness of the treatment, due to the fact that particular single nucleotide polymorphisms (SNPs), i.e., CYP3A4*1B y CYP3A4*2, have shown to exert a significant influence on the metabolic activity of this pharmacologically important enzyme.Objective: Evaluate the frequency of pharmacogenetically important polymorphisms in the CYP3A4 gen in a Colombian population of patients with CML being treated with this novel drug (Imatinib), in parallel with a control population of 164 healthy individuals. Correlate the evolution of the clonal expansion Ph(+) with the presence of these SNPs and the length of treatment.Methodology: PCR-RFLP genotyping for the CYP3A4* 1B y CYP3A4*2 SNPs. RBHG replication banding for the evaluation of the presence of the Ph(+) markers in spontaneous mitotic blasts.Results: A positive cytogenetic response and/or correlation was detected between the length of the imatinib treatment and a reduction in the percentage of Ph(+) blasts. Genotyping indicate that CYP3A4*1B polymorphism does no affect the cytogenetic response in imatinib treated Ph(+) patients, and that the pharmacorelevant CYP3A4*2 SNP is not present in this population of patients and controls (N=194). Conclusions: The pharmacogenotype CYP3A4*2 (exon 7) does not affect the induced positive cytogenetic response triggered by the imatinib treatment, that generally induces a reduction in Ph(+) blasts en relation with the duration of the treatment.

Análise citogenética e FISH no monitoramento da LMC em tratamento com inibidores da tirosino quinase / Cytogenetics and FISH monitoring CML during tyrosine kinase inhibitors treatment

O monitoramento de tratamento com inibidor da tirosinoquinase (TK) tem sido feito com os objetivos de avaliar o sucesso da terapia e de definircondutas específicas nos casos nos quais não se obtem a remissão da LMC; naqueles em que ocorre a perda da remissão previamente alcançada, na eventualidade ou não de suspensão da medicação; quando há a evolução clonal a despeito da terapia ou o aparecimento de alterações clonais nas células Philadelphia (Ph)-negativas. Recomenda-se a avaliação citogenética aos três ou seis meses de instituição da terapêutica e, a partir daí, a cada seis meses até a remissão citogenética completa. Uma vez alcançada a remissão citogenética, o monitoramento passa a ser porPCR quantitativo em tempo real (PCR em tempo real, porém o cariótipo deve ser realizado a cada ano para a detecção de perda de resposta, alterações clonais em células Ph-negativas ou evolução clonal. Com efeito, só o cariótipo pode monitorar a aquisição de alteração clonal associada à progressão da doença. No presente manuscrito são também discutidos: Ph-variantes, deleção no derivado 9q e aparecimento de alterações clonais nas células Ph-negativas, situações menos freqüentes, mas que merecem monitoração mais amiúde.

Tyrosine kinase inhibitor treatment monitoring is performed in order to evaluate the success of therapy and to allow specific changes in cases in which remission was not obtained, was lost after being achieved with or without drug interruption, when clonal evolution occurs despite therapy or when clonal abnormalities are detected in Ph-negative cells. It is recommended to perform marrow karyotyping at three or six months after starting therapy and then at six-month intervals until complete cytogenetic remission (CCR) is achieved. Once in CCR, quantitative real time PCR is the method of choice for monitoring, but karyotyping should be performed every year to detect loss of response, clonal evolution or clonal abnormalities in Ph-negative cells. In fact, only karyotyping can monitor the acquisition of clonal aberrations related to disease progression. In this article situations less frequently found, but deserving close monitoring, such as variant Ph, deletion on derivative chromosome 9q and clonal aberrations in Ph-negative cells are also discussed.

Leucemia Linfoblástica Aguda Filadélfia positiva / Phyladelphia positive Acute Lymphoblastic Leukemia

O cromossomo Filadélfia (Ph1) é a alteração citogenética mais comum da Leucemia Linfoblástica Aguda do adulto (LLA). Esta alteração citogenética predomina nos adultos com mais de 50 anos e na LLA de origem na célula B, principalmente CD10 positiva. O diagnóstico requer a análise citogenética e a pesquisa do mRNA do gene BCR-ABL no sangue periférico ou na medula óssea. A LLA Ph1 apresenta uma sobrevida global em cinco anos inferior a 20 por cento quando tratada com protocolos para LLA. Os poucos casos de cura ocorrem nos pacientes submetidos ao transplante alogênico de medula óssea (TMO). A adição do imatinibe à quimioterapia resultou em melhora na taxa de remissão completa, maior taxa de remissão molecular completa, maior número de pacientes aptos para realizar o TMO, uma maior sobrevida livre de eventos e maior sobrevida global, embora o tempo de seguimento seja ainda muito curto. Entretanto, a taxa de recaídas e o aparecimento de mutações do BCR-ABL resistentes ao imatinibe ainda são preocupantes. No futuro, novos inibidores de tirosina quinase poderão ser incorporados ao tratamento da LLA Ph1.

The Philadelphia chromosome (Ph1) is the most frequent abnormality in acute adult lymphoblastic leukemia (ALL). Ph1 positive ALL is more frequent in over 50-year-old adults, in B-cell ALL and CD10-positive ALL. Diagnosis is based on the identification of the BCR-ABL gene mRNA in peripheral blood or bone marrow. The 5-year overall survival of patients with Ph1 positive ALL treated with chemotherapy alone is less than 20 percent. A few cases may be cured by allogeneic stem cell transplantation. The addition of imatinib to the chemotherapeutic treatment has resulted in more complete remissions, more complete molecular responses, more patients able to perform stem cell transplantation, better event-free survival and better overall survival, although the study follow-up period is very short so far. High relapse rates and the emergence of BCR-ABL mutants resistant to imatinib are still significant. In the future, newer tyrosine-kinase inhibitors may be added to the chemotherapy.