RESUMO
Chronic Myeloid Leukemia is a clonal disorder characterized by the presence of the Ph-chromosome and the BCR-ABL tyrosine-kinase (TK). Target-therapy with Imatinib has greatly improved its outcome. Deeper and faster responses are reported with the second-generation TKI Nilotinib. Sustained responses may enable TKI discontinuation. However, even in a complete molecular response, some patients experience disease recurrence possibly due to persistence of quiescent leukemic CD34+/lin-Ph+ stem cells (LSCs). Degree and mechanisms of LSCs clearance during TKI treatment are not clearly established. The PhilosoPhi34 study was designed to verify the in-vivo activity and timecourse of first-line Nilotinib therapy on BM CD34+/lin-Ph+ cells clearance. Eighty-seven CP-CML patients were enrolled. BM cells were collected and tested for Ph+ residual cells, at diagnosis, 3, 6 and 12 months of treatment. FISH analysis of unstimulated CD34+/lin- cells in CCyR patients were positive in 8/65 (12.3%), 5/71 (7%), 0/69 (0%) evaluable tests, respectively. Per-Protocol analysis response rates were as follows: CCyR 95% at 12 months, MR4.5 31% and 46% at 12 and 36 months, respectively. An exploratory Gene Expression Profiling (GEP) study of CD34+/lin- cells was performed on 30 patients at diagnosis and after, on 79 patients at diagnosis vs 12 months of nilotinib treatment vs 10 healthy subjects. Data demonstrated some genes significantly different expressed: NFKBIA, many cell cycle genes, ABC transporters, JAK-STAT signaling pathway (JAK2). In addition, a correlation between different expression of some genes (JAK2, OLFM4, ICAM1, NFKBIA) among patients at diagnosis and their achievement of an early and deeper MR was observed.
Assuntos
Antineoplásicos/uso terapêutico , Regulação Leucêmica da Expressão Gênica/efeitos dos fármacos , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Células-Tronco Neoplásicas/efeitos dos fármacos , Inibidores de Proteínas Quinases/uso terapêutico , Pirimidinas/uso terapêutico , Transportadores de Cassetes de Ligação de ATP/genética , Transportadores de Cassetes de Ligação de ATP/metabolismo , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Farmacológicos , Medula Óssea/efeitos dos fármacos , Medula Óssea/metabolismo , Medula Óssea/patologia , Estudos de Casos e Controles , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Feminino , Perfilação da Expressão Gênica , Fator Estimulador de Colônias de Granulócitos/genética , Fator Estimulador de Colônias de Granulócitos/metabolismo , Humanos , Molécula 1 de Adesão Intercelular/genética , Molécula 1 de Adesão Intercelular/metabolismo , Janus Quinase 2/genética , Janus Quinase 2/metabolismo , Leucemia Mielogênica Crônica BCR-ABL Positiva/diagnóstico , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Masculino , Pessoa de Meia-Idade , Inibidor de NF-kappaB alfa/genética , Inibidor de NF-kappaB alfa/metabolismo , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Cromossomo Filadélfia , Estudos Prospectivos , RecidivaRESUMO
Chronic myeloid leukemia (CML) is characterized by the constitutive tyrosine kinase activity of the oncoprotein BCR-ABL1 in myeloid progenitor cells that activates multiple signal transduction pathways leading to the leukemic phenotype. The tyrosine-kinase inhibitor (TKI) nilotinib inhibits the tyrosine kinase activity of BCR-ABL1 in CML patients. Despite the success of nilotinib treatment in patients with chronic-phase (CP) CML, a population of Philadelphia-positive (Ph+) quiescent stem cells escapes the drug activity and can lead to drug resistance. The molecular mechanism by which these quiescent cells remain insensitive is poorly understood. The aim of this study was to compare the gene expression profiling (GEP) of bone marrow (BM) CD34+/lin- cells from CP-CML patients at diagnosis and after 12 months of nilotinib treatment by microarray, in order to identify gene expression changes and the dysregulation of pathways due to nilotinib action. We selected BM CD34+/lin- cells from 78 CP-CML patients at diagnosis and after 12 months of first-line nilotinib therapy and microarray analysis was performed. GEP bioinformatic analyses identified 2,959 differently expressed probes and functional clustering determined some significantly enriched pathways between diagnosis and 12 months of nilotinib treatment. Among these pathways, we observed the under expression of 26 genes encoding proteins belonging to the cell cycle after 12 months of nilotinib treatment which led to the up-regulation of chromosome replication, cell proliferation, DNA replication, and DNA damage checkpoint at diagnosis. We demonstrated the under expression of the ATP-binding cassette (ABC) transporters ABCC4, ABCC5, and ABCD3 encoding proteins which pumped drugs out of the cells after 12 months of nilotinib. Moreover, GEP data demonstrated the deregulation of genes involved in the JAK-STAT signaling pathway. The down-regulation of JAK2, IL7, STAM, PIK3CA, PTPN11, RAF1, and SOS1 key genes after 12 months of nilotinib could demonstrate the up-regulation of cell cycle, proliferation and differentiation via MAPK and PI3K-AKT signaling pathways at diagnosis.
Assuntos
Transportadores de Cassetes de Ligação de ATP/sangue , Ciclo Celular/efeitos dos fármacos , Regulação Leucêmica da Expressão Gênica/efeitos dos fármacos , Janus Quinases/sangue , Leucemia Mielogênica Crônica BCR-ABL Positiva/sangue , Proteínas de Neoplasias/sangue , Pirimidinas/administração & dosagem , Fatores de Transcrição STAT/sangue , Transdução de Sinais/efeitos dos fármacos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de TempoAssuntos
Células da Medula Óssea/efeitos dos fármacos , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Pirimidinas/farmacologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antígenos CD34/análise , Células da Medula Óssea/patologia , Contagem de Células , Feminino , Humanos , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Células-Tronco Neoplásicas/patologia , Estudos Prospectivos , Inibidores de Proteínas Quinases/uso terapêutico , Adulto JovemRESUMO
BACKGROUND: Chronic myeloid leukemia (CML) is a clonal myeloproliferative disorder with heterogeneous biological and clinical features. The biomolecular mechanisms of CML response to tyrosine-kinase inhibitors are not fully defined. OBJECTIVE: We undertook a gene expression profiling (GEP) study of selected bone marrow (BM) CD34+/lin- cells of chronic-phase CML patients at diagnosis and after 12 months of TKI nilotinib to investigate molecular signatures characterizing both conditions.
