Dasatinib in chronic myeloid leukemia: a review

Deregulated BCR-ABL tyrosine kinase (TK) activity is the molecular marker for chronic myeloid leukemia (CML), which provides an identifiable target for developing therapeutic agents. Imatinib mesylate, a BCR-ABL TK inhibitor, is the frontline therapy for CML. Despite the stunning efficacy of this agent, a small number of patients develop a suboptimal response or resistance to imatinib. In newly diagnosed patients with chronic phase CML, the rate of resistance to imatinib at 4 years was up to 20%, increasing to 70% to 90% for patients in the accelerated/blastic phase. Resistance to imatinib led to the development of novel TK inhibitors such as dasatinib. Several clinical trials have reported more durable complete hematologic and cytogenetic responses with this agent in patients who are resistant or intolerant to imatinib. Dasatinib is well tolerated and has broad efficacy, resulting in durable responses in patients with any BCR-ABL mutation except for T3151 and mutations in codon 317 – most commonly F317L – including mutations that were highly resistant to imatinib, such as L248, Y253, E255, F359, and H396. Dasatinib is recommended for CML in chronic, blastic or accelerated phase that is resistant or intolerant to imatinib. Dasatinib was approved by the FDA at 100 mg once daily as the starting dose in patients with chronic phase CML and at 70 mg twice daily in patients with accelerated or blastic phase CML. Various clinical trial results provided evidence that resistance to one TK inhibitor can be reversed with the use of a different TK inhibitor (TKI). Other second-generation TKIs with activity in CML include nilotinib, bosutinib and INNO 406. New molecules, such as the inhibitor of Aurora family serine-threonine kinases, MK0457, which has antileukemic activity in CML associated with a T315I mutation, are being investigated. Allogeneic hematopoietic stem cell transplantation remains an option for selected patients

Outpatient and Home Chemotherapy with Novel Local Control Strategies in Desmoplastic Small Round Cell Tumor

Desmoplastic Small Round Cell Tumor (DSRCT) has a very poor prognosis. This report illustrates novel chemotherapy and local control interventions in a 5-year old patient. The patient was treated in the outpatient setting, achieved remission, with excellent quality of life. The patient presented with massive ascites and >1000 abdominal tumors. Neoadjuvant chemotherapy included vincristine (1.5 mg/m2), ifosfamide (3 g/m2/day × 3), dexrazoxane/doxorubicin (750/75 mg/m2), and etoposide (150 mg/m2). Continuous hyperthermic peritoneal perfusion (CHPP) with cisplatin (100 mg/m2) was given after extensive cytoreductive surgery. This was followed by irinotecan (10 mg/m2/day × 5 × 2 weeks) + temozolomide monthly × 2, then abdominal radiation 30 Gy with simultaneous temozolomide (100 mg/m2/day × 5). A total of 12 cycles of irinotecan and temozolamide were given. Except for initial chemotherapy, subsequent courses were in the outpatient setting. Focal retroperitoneal relapse at 18 months was treated with IMRT with bevacizumab (5 mg/kg) and 2 perihepatic metastases with radio frequency ablation/cryoablation followed by chronic outpatient maintenance chemotherapy (valproic acid, cyclophosphamide, and rapamycin). Almost 2 years from diagnosis, the patient maintained an excellent quality of life. This is a novel approach to the treatment of children with massive abdomino-pelvic DSRCT

Case report: ATIC-ALK fusion in infant-type hemispheric glioma and response to lorlatinib

IntroductionInfant type hemispheric gliomas are a rare tumor with unique molecular characteristics. In many cases these harbor mutations in receptor tyrosine kinase pathways and respond to targeted therapy. Here we describe the case of an infant with this type of tumor with a novel ATIC-ALK fusion that has responded dramatically to the ALK inhibitor lorlatinib, despite being refractory to standard chemotherapy.Case descriptionThe infant was initially treated with standard chemotherapy and found to have an ATIC-ALK fusion. When surveillance imaging revealed progressive disease, the patient was switched to the ALK-inhibitor lorlatinib at 47 mg/m2/day. The patient demonstrated a significant clinical and radiographic response to the ALK inhibitor lorlatinib after just 3 months of treatment and a near complete response by 6 months of therapy.ConclusionThe ALK inhibitor lorlatinib is an effective targeted therapy in infant type hemispheric glioma patients harboring ATIC-ALK fusion

Tetanus toxin Hc fragment induces the formation of ceramide platforms and protects neuronal cells against oxidative stress

Tetanus toxin (TeTx) is the protein, synthesized by the anaerobic bacteria Clostridium tetani, which causes tetanus disease. TeTx gains entry into target cells by means of its interaction with lipid rafts, which are membrane domains enriched in sphingomyelin and cholesterol. However, the exact mechanism of host membrane binding remains to be fully established. In the present study we used the recombinant carboxyl terminal fragment from TeTx (Hc-TeTx), the domain responsible for target neuron binding, showing that Hc-TeTx induces a moderate but rapid and sustained increase in the ceramide/sphingomyelin ratio in primary cultures of cerebellar granule neurons and in NGF-differentiated PC12 cells, as well as induces the formation of ceramide platforms in the plasma membrane. The mentioned increase is due to the promotion of neutral sphingomyelinase activity and not to the de novo synthesis, since GW4869, a specific neutral sphingomyelinase inhibitor, prevents neutral sphingomyelinase activity increase and formation of ceramide platforms. Moreover, neutral sphingomyelinase inhibition with GW4869 prevents Hc-TeTx-triggered signaling (Akt phosphorylation), as well as the protective effect of Hc-TeTx on PC12 cells subjected to oxidative stress, while siRNA directed against nSM2 prevents protection by Hc-TeTx of NSC-34 cells against oxidative insult. Finally, neutral sphingomyelinase activity seems not to be related with the internalization of Hc-TeTx into PC12 cells. Thus, the presented data shed light on the mechanisms triggered by TeTx after membrane binding, which could be related with the events leading to the neuroprotective action exerted by the Hc-TeTx fragment

EVA como herramienta para la toma de decisiones en portafolios estructurales en momentos de crisis

La bondad de la inversión en acciones de una empresa se mide en términos de la rentabilidad que el inversionista tiene respecto de dicha inversión, entendiendo como rentabilidad, el ingreso que recibe por medio de dividendos y/o por el aumento en el precio de sus accionesÍndice de Figuras. Índice de Tablas. Introducción. El Eva® Como Medida De Valoración. La Crisis Subprime. Reseña Sobre Los Sectores Económicos A Evaluar. Fundamentales Durante La Crisis En Las Empresas Seleccionadas. Modelo. Conclusiones. Referencias.Magíster en Fianzas Corporativas, CESA.Maestrí

Caracterización de cepas nativas colombianas de clostridios solventogénicos por perfiles de plásmidos

Este trabajo tuvo como objetivo caracterizar molecularmente trece cepas nativas de Clostridium solventogénicos aislados en suelos colombianos, con el propósito de establecer diferencias a través de sus perfiles plasmídicos. Se estandarizaron las condiciones para la extracción de plásmidos en estos microorganismos anaeróbicos y las condiciones para la digestión con enzimas de restricción. Todas las cepas nativas alojan al menos un plásmido que migra entre 20 y 34 kpb y 7 de ellas poseen un plásmido más, que migra entre 11 y 14 kpb. Los perfiles plasmídicos obtenidos con las enzimas empleadas fueron muy homogéneos y no permitieron diferenciar las cepas, lo cual muestra que estos marcadores moleculares no tienen poder discriminatorio para el estudio de los Clostridios.The objective of this work was the molecular characterisation of thirteen native Clostridium strains isolated from Colombian soils, with the purpose to establish differences between theirs plasmids profiles. A total plasmid extraction protocol was standardised for these anaerobic microorganisms during molecular characterisation and the conditions for endonucleases digestion also were standardised. A plasmid (molecular size between 20 and 34 kbp) was found in all of them. 7 possessed an extra plasmid ranging in size between 11 and 14 kbp. The plasmids profiles obtained with the endonucleases were very homogeneous and did not allow the differentiation between the strains

Drop metastases to the pediatric spine revealed with diffusion-weighted MR imaging

Identifying drop metastases to the spine from pediatric brain tumors is crucial to treatment and prognosis. MRI is currently the gold standard for identifying drop metastases, more sensitive than CSF cytology, but imaging is not uncommonly inconclusive. Although diffusion‐weighted imaging (DWI) of the brain is very useful in the evaluation of hypercellular tumors, DWI of the spine has not been clinically useful in children because of susceptibility artifacts and lack of spatial resolution. A new technique, readout-segmented echo planar imaging (EPI), has improved these images, allowing for identification of hypercellular drop metastases. We report a case that illustrates the utility of spine DWI in the detection of metastatic disease in children with primary central nervous system (CNS) tumors. This case suggests that DWI of the spine with readout-segmented EPI should be included in the evaluation for drop metastases