PRECLINICAL RATIONALE FOR THE USE OF THE AKT INHIBITOR PERIFOSINE IN COMBINATION WITH THE MULTIKINASE INHIBITOR SORAFENIB IN HODGKIN LYMPHOMA

INTRODUCTION: A significant proportion of Hodgkin lymphoma (HL) patients refractory to first-line chemotherapy or relapsing after autologous transplantation are not cured with currently available treatments and require new treatments. The PI3K/AKT and RAF/MEK/ERK pathways are constitutively activated in the majority of HL. These pathways can be targeted using the AKT inhibitor perifosine (\uc6terna Zentaris GmBH, Germany, EU), and the RAF/MEK/ERK inhibitor sorafenib (Nexavar\uae, Bayer, Germany, EU). We hypothesized that perifosine in combination with sorafenib might have a therapeutic activity in HL by overcoming the cytoprotective and anti-apoptotic effects of PI3K/Akt and RAF/MEK/ERK pathways. Since preclinical evidence supporting the anti-lymphoma effects of the perifosine/sorafenib combination are still lacking, the present study aimed at investigating in vitro and in vivo the activity and mechanism(s) of action of this two-drug combination. METHODS: Three HL cell lines (HD-MyZ, L-540 and HDLM-2) were used to investigate the effects of perifosine and sorafenib using in vitro assays analyzing cell growth, cell cycle distribution, gene expression profiling (GEP), and apoptosis. Western blotting (WB) experiments were performed to determine whether the two-drug combination affected MAPK and PI3K/AKT pathways as well as apoptosis. Additionally, the antitumor efficacy and mechanism of action of perifosine/sorafenib combination were investigated in vivo in nonobese diabetic/severe combined immune-deficient (NOD/SCID) mice using tumor growth rates and survival as endpoints. RESULTS: While perifosine and sorafenib as single agents exerted a limited activity against HL cells, exposure of HD-MyZ and L-540 cell lines, but not HDLM-2 cells, to perifosine/sorafenib combination resulted in synergistic cell growth inhibition (40% to 80%) and cell cycle arrest. Upon perifosine/sorafenib exposure, L-540 cell line showed significant levels of apoptosis (up to 70%, P 64.0001) associated with severe mitochondrial dysfunction (cytochrome c, apoptosis-inducing factor release and marked conformational change of Bax accompanied by membrane translocation). Apoptosis induced by perifosine/sorafenib combination did not result in processing of caspase-8, -9, -3, or cleavage of PARP, and was not reversed by the pan-caspase inhibitor Z-VADfmk, supporting a caspase-independent mechanism of apoptosis. In responsive cell lines, WB analysis showed that anti-proliferative events were associated with dephosphorylation of MAPK and PI3K/Akt pathways. GEP analysis of HD-MyZ and L-540 cell lines, but not HDLM-2 cells indicated that perifosine/sorafenib treatment induced upregulation of genes involved in amino acid metabolism and downregulation of genes regulating cell cycle, DNA replication and cell death. In addition, in responsive cell lines, perifosine/sorafenib combination strikingly induced the expression of tribbles homologues 3 (TRIB3) both in vitro and in vivo. Silencing of TRIB3 prevented cell growth reduction induced by perifosine/sorafenib treatment. In vivo, the combined perifosine/sorafenib treatment significantly increased the median survival of NOD/SCID mice xenografted with HD-MyZ cell line as compared to controls (81 vs 45 days, P 64.0001) as well as mice receiving perifosine alone (49 days, P 64.03) or sorafenib alone (54 days, P 64.007). In addition, perifosine/sorafenib treatment had no effect on HDLM-2 nodules, but significantly reduced L-540 nodules with 50% tumor growth inhibition (P 64.0001), compared to controls. In mice bearing subcutaneous nodules generated by HD-MyZ and L-540 cell lines but not HDLM-2 cell line, perifosine/sorafenib treatment induced significantly increased levels of apoptosis (2- to 2.5-fold, P 64.0001) and necrosis (2- to 8-fold, P 64.0001), as compared to controls or treatment with single agents. CONCLUSIONS: Perifosine/sorafenib combination resulted in potent anti-HL activity both in vitro and in vivo. These results warrant clinical evaluation in HL patients

A produção orgânica no município de Cacoal, RO: uma análise da dinâmica econômica e o desenvolvimento sustentável.

A preocupação com a segurança alimentar, qualidade de vida e a questão ambiental vem ao longo do tempo adquirindo uma dinâmica em escala global com novos hábitos alimentares e modos de produção. Com o objetivo verificar o desenvolvimento produtivo e sua viabilidade comercial diante da implantação de sistemas orgânicos na associação dos produtores do município de Cacoal, RO buscou-se analisar e caracterizar as relações comerciais e sociais que se estabelece entre o produtor e consumidor sendo identificados os diferentes cenários como: produção, distribuição e comercialização no município, através do método de pesquisa com a identificação dos principais meios e espaços de comercialização e, a realização de entrevistas com os principais membros da associação e feirante envolvidos no processo. Conclui-se que diante dos obstáculos a serem superados, a produção e a comercialização agroecológica apresenta possibilidades de expansão no município

Atributos químicos e físicos de um Latossolo e rendimento de milho em diferentes sistemas de manejo da capoeira.

Este trabalho teve como objetivo avaliar os atributos químicos e físicos de um Latossolo e o rendimento de milho em diferentes sistemas de manejo da capoeira. Os atributos de solo avaliados foram: resistência do solo ao penetrômetro, determinada no campo, densidade de solo, matéria orgânica do solo, pH-H2O, cálcio e magnésio trocáveis (KCl 1M), alumínio trocável (KCl 1M), acidez titulável (H+Al) e potássio extraíveis (Mehlich 1).bitstream/CPAF-RO-2010/14573/1/352-milho.pd

Burning magnesium, a sparkle in acute inflammation: gleams from experimental models

Magnesium contributes to the regulation of inflammatory responses. Here, we focus on the role of magnesium in acute inflammation. Although present knowledge is incomplete to delineate an accurate scenario and a schedule of the events occurring under magnesium deficiency, it emerges that low magnesium status favors the induction of acute inflammation by sensitizing sentinel cells to the noxious agent, and then by participating to the orchestration of the vascular and cellular events that characterize the process

Light filth method on semolina and pasta

Samples of semolina and pasta were collected from one mill and one pasta plant in Italy for six and four years respectively. They were analyzed by AOAC light filth method (225 g). Altogether, 195 semolina were collected from 2007 to 2012. The mean number of insect fragments detected during this period was 4.9, and each year, a mean of one first instar larva of Stegobium paniceum (L.) was found. A single mite was detected in only one sample. A total of 156 samples of pasta were analyzed during the period 2009 to 2012 and the mean number of fragments in these samples was 10.1. Mandibles of Sitophilus oryzae (L.) and Tribolium spp. were the most identified filths. Fragments were mainly derived from infestation prior to milling, both in semolina and pasta samples. In fact, fragment size was lower than the granulometry of semolina. Rodent hair was found in few samples

Shortest path with acceleration constraints: complexity and approximation algorithms

We introduce a variant of the Shortest Path Problem (SPP), in which we impose additional constraints on the acceleration over the arcs, and call it Bounded Acceleration SPP (BASP). This variant is inspired by an industrial application: a vehicle needs to travel from its current position to a target one in minimum-time, following pre-defined geometric paths connecting positions within a facility, while satisfying some speed and acceleration constraints depending on the vehicle position along the currently traveled path. We characterize the complexity of BASP, proving its NP-hardness. We also show that, under additional hypotheses on problem data, the problem admits a pseudo-polynomial time-complexity algorithm. Moreover, we present an approximation algorithm with polynomial time-complexity with respect to the data of the original problem and the inverse of the approximation factor ϵ. Finally, we present some computational experiments to evaluate the performance of the proposed approximation algorithm

Otimização das técnicas de PCR e RFLP para o gene tbpA de Haemophilus parasuis.

Projeto/Plano de Ação: 03.07.05.017

Caracterização visual de sintomas de deficiências em mudas de bandarra (Schizolobium parahyba var. amazonicum (Huber ex Ducke) Barneby).

Este estudo teve por objetivo caracterizar os sintomas visuais de deficiência de macronutrientes e micronutrientes em mudas de bandarra.bitstream/item/24800/1/ct89-bandarra.pd