Bone metastasis of lung adenocarcinoma (AC) is a frequent complication of advanced disease. The purpose of this study was to identify key mediators conferring robust prometastatic activity with clinical significance. We isolated highly metastatic subpopulations (HMS) using a previously described in vivo model of lung AC bone metastasis. We performed transcriptomic profiling of HMS and stringent bioinformatics filtering. Functional validation was assessed by overexpression and lentiviral silencing of single, double and triple combination in vivo and in vitro. We identified HDAC4, PITX1 and ROBO1 that decreased bone metastatic ability after their simultaneous abrogation. These effects were solely linked to defects in osseous colonization. The molecular mechanisms related to bone colonization were mediated by non-cell autonomous effects that include the following: (1) a marked decrease in osteoclastogenic activity in vitro and in vivo, an effect associated with reduced pro-osteoclastogenic cytokines IL-11 and PTHrP expression levels, as well as decreased in vitro expression of stromal rankl in conditions mimicking tumor–stromal interactions; (2) an abrogated response to TGF-β signaling by decreased phosphorylation and levels of Smad2/3 in tumor cells and (3) an impaired metalloproteolytic activity in vitro. Interestingly, coexpression of HDAC4 and PITX1 conferred high prometastatic activity in vivo. Further, levels of both genes correlated with patients at higher risk of metastasis in a clinical lung AC data set and with a poorer clinical outcome. These findings provide functional and clinical evidence that this metastatic subset is an important determinant of osseous colonization. These data suggest novel therapeutic targets to effectively block lung AC bone metastasis.

Fundamento: El objetivo de este estudio radica en la determinación de la validez del factor de crecimiento transformante β (TGF-β) como diana terapéutica en modelos de metástasis óseas derivadas de distintos tipos histopatológicos del cáncer de pulmón. Material y métodos: Ratones inmunodeprimidos de 4 semanas de edad inoculados con líneas de cáncer de pulmón y de mama fueron tratados con péptido inhibidor de la citoquina, péptido control o placebo. Se tomaron semanalmente medidas de bioluminiscencia y microrradiografías para determinar el efecto del tratamiento sobre la carga tumoral presente en los huesos largos y las lesiones metastásicas en los mismos. Resultados: El tratamiento con el péptido específico frente a TGF-β tiene un efecto protector en el hueso en los animales inoculados con la línea de cáncer de mama, a diferencia de lo ocurrido en los grupos de péptido control y placebo. Sin embargo, el tratamiento anti-TGF-β carece de efectos terapéuticos significativos sobre las metástasis óseas que se desarrollan en los animales inoculados con las líneas de cáncer de pulmón empleadas. Conclusiones: El carácter de TGF-β como posible diana terapéutica en metástasis en hueso es altamente dependiente del tipo y subtipos histopatológicos de tumor.

Las neoplasias mieloproliferativas cronicas (NMPC) BCR-ABL1 negativas engloban a un grupo heterogeneo de trastornos clonales de la hematopoyesis, poco frecuentes, caracterizadas por la proliferacion clonal excesiva de uno o mas linajes de la linea mieloide y por la ausencia de BCR-ABL1. La mutacion V617F de JAK2, presente en un 50-90% de las NMPCs BCR-ABL1 negativas clasicas, (PV, TE y MFI), afecta al dominio autoinhibitorio de dicha proteina y provoca un aumento de su actividad TK. Dicha mutacion, tambien ha sido descrita en el 20% de las NMPC atipicas (NMPCa). Ademas, se han descrito otras de menor prevalencia en el exon 12 que situan a JAK2, como uno de los principales genes candidatos en el estudio de la patogenesis de estas enfermedades.

Chronic myeloproliferative neoplasms (CMPNs) are clonal disorders of the hematopoietic stem cells, characterized by abnormal proliferation and survival of one or more cells of the myeloid lineage. BCR-ABL1 negative CMPNs are a heterogeneous group of diseases for which the molecular pathogenesis is not well understood. Over the last years some genetic alterations have been described, most of them activating some tyrosine kinase genes playing a role similar to ABL1 in CML. Tyrosine kinases (TK) have an important role in cell growth and oncogenesis. Deregulation of TK genes (mainly due to translocations, amplifications or point mutations) can result in constitutive activation of the signalling pathways in which they are involved, causing the abnormal proliferation and survival that characterize these pathologies. In this study, we have analysed all genes from the families Jak (JAK1, JAK2, JAK3 and TYK2), Abl (ABL1 and ABL2) and Syk (SYK and ZAP70) of TKs. All of them code for cytoplasmic tyrosine kinase proteins and some of them have been found mutated in CMPNs and in other tumor types. We have used FISH to detect cryptic rearrangements and dHPLC to detect sequence mutations on samples from 44 BCR-ABL1 negative and V617FJAK2 negative CMPN patients. Both analyses have shown that these genes are no frequently mutated in these diseases, implying that lesions in other genes must be involved in the pathogenesis of these diseases. Abstract #1496. Haematologica/The Hematology Journal 2009;94 (Suppl. 2): pp. 581. XIV Congress of1496. Haematologica/The Hematology Journal 2009;94 (Suppl. 2): pp. 581. XIV Congress of the European Haematology Association. Berlin Alemania. 4-7 Junio, 2009

Este trabajo ha sido financiado con ayudas del Fondo de Investigacion Sanitaria del Instituto Carlos III (FIS PI040037) del Ministerio de Ciencia e Innovacion (SAF2007-62473), del Plan de Investigacion de la Universidad de Navarra (Linea Especial) y de la Fundacion Caja Navarra a traves del Programa “Tu eliges, tu decides” (Proyecto 10.830) Material y metodos Se han incluido muestras de 27 pacientes con distintas NMPCs (2 con mielofibrosis idiopatica –MFI-, 6 con trombocitemia esencial –TEy 19 con NMPCs atipicas). Se ha descartado la presencia de BCR-ABL1 y V617FJAK2 mediante FISH/RT-PCR y ARMS-PCR respectivamente. Se ha llevado a cabo una busqueda de reordenamientos cromosomicos para todos los genes de las familias III (PDGFRA, PDGFRB, CSF1R, KIT y FLT3) y IV (FGFR1, FGFR2, FGFR3 and FGFR4) de las RTKs, asi como de genes de las familias Jak (JAK1, JAK2, JAK3 y TYK2), Abl (ABL1 y ABL2) y Syk (SYK y ZAP70) de las CTKs. Para ello, se han empleado sondas no comerciales flanqueantes a cada uno de los genes. Las sondas localizadas en el extremo 5 fueron marcadas con Spectrum Orange y las sondas del extremo 3 con Spectrum Green (Tabla 1)

BCR-ABL1 negative chronic myeloproliferative neoplasms (CMPNs) are a heterogeneous group of clonal haematological malignancies. Over the last years, some genetic alterations have been described to cause these diseases, most of them activating tyrosine kinase (TK) genes. Tyrosine kinases (TK) have an important role in cell growth and oncogenesis, as gain-of-function mutations can lead to the constitutive activation of the signalling pathways in which they are involved. In this study, we have analysed all genes from the families III (PDGFRA, PDGFRB, CSF1R, KIT and FLT3) and IV (FGFR1, FGFR2, FGFR3 and FGFR4) of RTKs. All of them code for receptors with tyrosine kinase activity and some of them have been found mutated in CMPNs and in other tumor types. We have used FISH to detect cryptic rearrangements and dHPLC to detect sequence mutations on samples from 44 BCR-ABL1 negative and V617FJAK2 negative CMPN patients. Both analyses have shown that these genes are no frequently mutated in these diseases, implying that molecular events or cryptic rearrangements causing these diseases, if they exist, must be located in other genes. Abstract #1495. Haematologica/The Hematology Journal 2009;94 (Suppl. 2): pp. 581. XIV Congress of the European Haematology Association. Berlin Alemania. 4-7 Junio, 20091495. Haematologica/The Hematology Journal 2009;94 (Suppl. 2): pp. 581. XIV Congress of the European Haematology Association. Berlin Alemania. 4-7 Junio, 2009