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Abstract We describe the geographical variation in tree species composition across Amazonian forests and show how environmental conditions are associated with species turnover. Our analyses are based on 2023 forest inventory plots (1 ha) that provide abundance data for a total of 5188 tree species. Within-plot species composition reflected both local environmental conditions (especially soil nutrients and hydrology) and geographical regions. A broader-scale view of species turnover was obtained by interpolating the relative tree species abundances over Amazonia into 47,441 0.1-degree grid cells. Two main dimensions of spatial change in tree species composition were identified. The first was a gradient between western Amazonia at the Andean forelands (with young geology and relatively nutrient-rich soils) and central–eastern Amazonia associated with the Guiana and Brazilian Shields (with more ancient geology and poor soils). The second gradient was between the wet forests of the northwest and the drier forests in southern Amazonia. Isolines linking cells of similar composition crossed major Amazonian rivers, suggesting that tree species distributions are not limited by rivers. Even though some areas of relatively sharp species turnover were identified, mostly the tree species composition changed gradually over large extents, which does not support delimiting clear discrete biogeographic regions within Amazonia.

Abstract Neratinib is a tyrosine kinase inhibitor that is used for the therapy of patients with HER2+ breast tumors. However, despite its clinical benefit, resistance to the drug may arise. Here we have created cellular models of neratinib resistance to investigate the mechanisms underlying such resistance. Chronic neratinib exposure of BT474 human HER2+ breast cancer cells resulted in the selection of several clones resistant to the antiproliferative action of the drug. The clones were characterized biochemically and biologically using a variety of techniques. These clones retained HER2 levels similar to parental cells. Knockdown experiments showed that the neratinib-resistant clones retained oncogenic dependence on HER2. Moreover, the tyrosine phosphorylation status of BT474 and the resistant clones was equally sensitive to neratinib. Transcriptomic and Western analyses showed that peptidylarginine deiminase 3 was overexpressed in the three neratinib-resistant clones studied but was undetectable in BT474 cells. Experiments performed in the neratinib-resistant clones showed that reduction of PADI3 or inhibition of its function restored sensitivity to the antiproliferative action of neratinib. Moreover, overexpression of FLAG-tagged PADI3 in BT474 cells provoked resistance to the antiproliferative action of neratinib. Together, these results uncover a role of PADI3 in the regulation of sensitivity to neratinib in breast cancer cells overexpressing HER2 and open the possibility of using PADI3 inhibitors to fight resistance to neratinib.

Abstract Introduction Hotspots (HS) mutations in the PIK3CA gene may lead to poorer oncological outcomes and endocrine resistance in advanced breast cancer (BC), but their prognostic role in early‐stage disease remains controversial. The overall agreement within plasma and tissue methods has not been well explored. Our aim was to correlate tissue and plasma approaches and to analyze the prognostic impact of PIK3CA mutations (PIK3CAm) in HR+/HER2− BC. Methods A retrospective and unicentric analysis of PIK3CA mutational status in tissue and plasma samples by Cobas®PIK3CA Mutation Kit in patients with HR+/HER2− BC. Results We analyzed 225 samples from 161 patients with luminal BC. PIK3CA mutations were identified in 62 patients (38.5%), of which 39.6% were found in tissue and 11.8% in plasma. In advanced disease, plasma and tissue correlation rate was performed in 64 cases, with an overall agreement of 70.3%. Eighty patients were treated with CDK4/6 inhibitors + endocrine therapy. We observed a moderately worse progression‐free survival (PFS) in PIK3CAm versus wild‐type (WT) (24 m vs. 30 m; HR = 1.39, p = 0.26). A subanalysis was carried out based on exons 9 and 20, which showed a statistically poorer PFS in PIK3CAm exon 9 versus 20 population (9.7 m vs. 30.3 m; HR = 2.84; p = 0.024). Furthermore, detection of PIK3CAm in plasma was linked to a worse PFS vs PIK3CAm detection just in tissue (12.4 vs. 29.3; HR = 2.4; p = 0.08). Conclusions Our findings suggest the PIK3CA evaluation in tissue as the diagnostic method of choice, however, additional investigations are required to improve the role of liquid biopsy in the PIK3CA assessment. PIK3CAm show worse outcomes in advanced luminal BC, especially in exon 9 mutation carriers, despite visceral involvement, prior exposure to endocrine therapy or detection of PIK3CAm in plasma, with an unclear prognosis in early‐stage disease. Nonetheless, this should be validated in a prospective cohort study.

Antecedentes: Un ejemplar colectado en Yoloxóchitl (San Luis Acatlán, Guerrero, México) fue anteriormente revisado por Michael Nee, quien sugirió que podría tratarse de una nueva especie del género Cestrum, y concedió al primer autor su descripción. Preguntas: Las poblaciones de Cestrum de San Luis Acatlán, Guerrero, corresponden a una nueva especie para la ciencia? Especies de estudio: Cestrum sp. nov. Sitio y años de estudio: Yoloxóchitl, Municipio de San Luis Acatlán, Guerrero; 2023-2024. Métodos: Se examinó bibliografía especializada en el género, obteniendo una lista de especies con morfología similar a la especie en estudio, las cuales se examinaron por medio de fotografías digitales de alta resolución. Se realizó una exploración botánica, ubicando tres poblaciones. Se realizó un análisis morfológico con el material colectado. Resultados: Se define a Cestrum amithii como una especie nueva para la ciencia, endémica de la comunidad de Yoloxóchitl, Guerrero. La nueva especie presenta diversas diferencias en cuanto a caracteres florales y foliares respecto a las otras especies del género, la más destacada es el cáliz espatáceo, éste es marcadamente asimétrico, de grandes dimensiones, con costillas evidentes y dos o tres lóbulos. C. amithii es endémica de México, distribuida en vegetación de bosque tropical subcaducifolio, en elevación de 530-630 m snm, sobre arroyos y corrientes estacionales. Conclusiones: Con este nuevo descubrimiento, en la flora del estado de Guerrero se contabilizan 16 especies del género Cestrum.

Abstract Using 2.046 botanically-inventoried tree plots across the largest tropical forest on Earth, we mapped tree species-diversity and tree species-richness at 0.1-degree resolution, and investigated drivers for diversity and richness. Using only location, stratified by forest type, as predictor, our spatial model, to the best of our knowledge, provides the most accurate map of tree diversity in Amazonia to date, explaining approximately 70% of the tree diversity and species-richness. Large soil-forest combinations determine a significant percentage of the variation in tree species-richness and tree alpha-diversity in Amazonian forest-plots. We suggest that the size and fragmentation of these systems drive their large-scale diversity patterns and hence local diversity. A model not using location but cumulative water deficit, tree density, and temperature seasonality explains 47% of the tree species-richness in the terra-firme forest in Amazonia. Over large areas across Amazonia, residuals of this relationship are small and poorly spatially structured, suggesting that much of the residual variation may be local. The Guyana Shield area has consistently negative residuals, showing that this area has lower tree species-richness than expected by our models. We provide extensive plot meta-data, including tree density, tree alpha-diversity and tree species-richness results and gridded maps at 0.1-degree resolution.

Abstract Background Advanced colorectal cancer (CRC) is difficult to treat. For that reason, the development of novel therapeutics is necessary. Here we describe a potentially actionable plasma membrane target, the amino acid transporter protein subunit CD98hc. Methods Western blot and immunohistochemical analyses of CD98hc protein expression were carried out on paired normal and tumoral tissues from patients with CRC. Immunofluorescence and western studies were used to characterize the action of a DM1-based CD98hc-directed antibody–drug conjugate (ADC). MTT and Annexin V studies were performed to evaluate the effect of the anti-CD98hc-ADC on cell proliferation and apoptosis. CRISPR/Cas9 and shRNA were used to explore the specificity of the ADC. In vitro analyses of the antitumoral activity of the anti-CD98hc-ADC on 3D patient-derived normal as well as tumoral organoids were also carried out. Xenografted CRC cells and a PDX were used to analyze the antitumoral properties of the anti-CD98hc-ADC. Results Genomic as well proteomic analyses of paired normal and tumoral samples showed that CD98hc expression was significantly higher in tumoral tissues as compared to levels of CD98hc present in the normal colonic tissue. In human CRC cell lines, an ADC that recognized the CD98hc ectodomain, reached the lysosomes and exerted potent antitumoral activity. The specificity of the CD98hc-directed ADC was demonstrated using CRC cells in which CD98hc was decreased by shRNA or deleted using CRISPR/Cas9. Studies in patient-derived organoids verified the antitumoral action of the anti-CD98hc-ADC, which largely spared normal tissue-derived colon organoids. In vivo studies using xenografted CRC cells or patient-derived xenografts confirmed the antitumoral activity of the anti-CD98hc-ADC. Conclusions The studies herewith reported indicate that CD98hc may represent a novel ADC target that, upon well-designed clinical trials, could be used to increase the therapeutic armamentarium against CRC.

Abstract In a time of rapid global change, the question of what determines patterns in species abundance distribution remains a priority for understanding the complex dynamics of ecosystems. The constrained maximization of information entropy provides a framework for the understanding of such complex systems dynamics by a quantitative analysis of important constraints via predictions using least biased probability distributions. We apply it to over two thousand hectares of Amazonian tree inventories across seven forest types and thirteen functional traits, representing major global axes of plant strategies. Results show that constraints formed by regional relative abundances of genera explain eight times more of local relative abundances than constraints based on directional selection for specific functional traits, although the latter does show clear signals of environmental dependency. These results provide a quantitative insight by inference from large-scale data using cross-disciplinary methods, furthering our understanding of ecological dynamics.

Abstract Background The dismal prognosis of advanced ovarian cancer calls for the development of novel therapies to improve disease outcome. In this regard, we set out to discover new molecular entities and to assess the preclinical effectiveness of their targeting. Methods Cell lines, mice and human ovarian cancer samples were used. Proteome profiling of human phosphokinases, in silico genomic analyses, genetic (shRNA and CRISPR/Cas9) and pharmacological strategies as well as an ex vivo human preclinical model were performed. Results We identified WNK1 as a highly phosphorylated protein in ovarian cancer and found that its activation or high expression had a negative impact on patients’ survival. Genomic analyses showed amplification of WNK1 in human ovarian tumours. Mechanistically, we demonstrate that WNK1 exerted its action through the MEK5–ERK5 signalling module in ovarian cancer. Loss of function, genetic or pharmacological experiments, demonstrated anti‐proliferative and anti‐tumoural effects of the targeting of the WNK1–MEK5–ERK5 route. Additional studies showed that this pathway modulated the anti‐tumoural properties of the MEK1/2 inhibitor trametinib. Thus, treatment with trametinib activated the WNK1–MEK5–ERK5 route, raising the possibility that this effect may limit the therapeutic benefit of ERK1/2 targeting in ovarian cancer. Moreover, in different experimental settings, including an ex vivo patient‐derived model consisting of ovarian cancer cells cultured with autologous patient sera, we show that inhibition of WNK1 or MEK5 increased the anti‐proliferative and anti‐tumour efficacy of trametinib. Conclusions The present study uncovers the participation of WNK1–MEK5–ERK5 axis in ovarian cancer pathophysiology, opening the possibility of acting on this pathway with therapeutic purposes. Another important finding of the present study was the activation of that signalling axis by trametinib, bypassing the anti‐tumoural efficacy of this drug. That fact should be considered in the context of the use of trametinib in ovarian cancer.

Abstract Background Despite the incorporation of novel therapeutics, advanced triple negative breast cancer (TNBC) still represents a relevant clinical problem. Considering this, as well as the clinical efficacy of antibody-drug conjugates (ADCs), we aimed at identifying novel ADC targets that could be used to treat TNBC. Methods Transcriptomic analyses were performed on TNBC and normal samples from three different studies. Plasma membrane proteins of three cell lines representative of the TNBC subtype were identified by cell surface biotinylation or plasma membrane isolation, followed by analyses of cell surface proteins using the Surfaceome online tool. Immunofluorescence and western studies were used to characterize the action of a CD98hc-directed ADC, which was prepared by in house coupling of emtansine to an antibody that recognized the ectodomain of CD98hc. Xenografted TNBC cells were used to analyze the antitumoral properties of the anti-CD98hc ADC. Results Comparative genomic studies between normal breast and TNBC tissues, together with proteomic and bioinformatic analyses resulted in the elaboration of a catalog of potential ADC targets. One of them, the CD98hc transmembrane protein, was validated as an ADC target. An antibody recognizing the ectodomain of CD98hc efficiently internalized and reached the lysosomal compartment. An emtansine-based ADC derived from such antibody was prepared and showed antitumoral properties in TNBC in vitro and in vivo models. Mechanistically, the anti-CD98hc ADC blocked cell cycle progression, that was followed by cell death caused by mitotic catastrophe. Conclusions This work describes a list of potential ADC targets in TNBC and validates one of them, the transmembrane protein CD98hc. The studies presented here also demonstrate the robustness of the multiomic approach herewith described to identify novel potential ADC targets.

A seguinte revisão bibliográfica sistemática teve como objetivo identificar os diferentes aspectos técnicos das emulsões Pickering, a importância e aplicação desta técnica na indústria de alimentos, com base nas propriedades mecânicas, físico-químicas e de estabilidade conferidos aos produtos alimentares. Nesta revisão bibliográfica, foram utilizadas diversas bases de dados acadêmicas, como Science Direct, Google Scholar, Scielo, Scopus, Elibro, entre outras. Como critério de seleção, foram considerados artigos científicos, livros, resenhas e todo material acadêmico relacionado ao assunto, e que foram publicados desde o ano de 2000 até o presente. De acordo com as fontes consultadas, verificou-se que este tipo de emulsão tem grande potencial para ser utilizado na produção de laticínios, bebidas, condimentos e da indústria alimentícia. Além disso, há uma crescente demanda por produtos com componentes alimentícios biologicamente ativos, nos quais as referidas emulsões aplicadas como agentes encapsulantes, auxiliam na preservação desses componentes, o que pode trazer benefícios nutricionais e de saúde aos consumidores. Uma investigação mais aprofundada das emulsões Pickering, ainda é necessária para avaliar o mecanismo de entrega, liberação de bioativos e compatibilidade com outros componentes de sistemas alimentares reais.

Abstract Background Treatment of renal cancer has significantly improved with the arrival to the clinic of kinase inhibitors and immunotherapies. However, the disease is still incurable in advanced stages. The fact that several approved inhibitors for kidney cancer target receptor tyrosine kinases (RTKs) suggests that these proteins play a critical role in the pathophysiology of the disease. Based on these precedents, we decided to explore whether RTKs other than those targeted by approved drugs, contribute to the development of kidney cancer. Methods The activation status of 49 RTKs in 44 paired samples of normal and tumor kidney tissue was explored using antibody arrays, with validation by western blotting. Genetic and pharmacologic approaches were followed to study the biological implications of targeting the epidermal growth factor receptor (EGFR) and its ligand Transforming Growth Factor-α (TGFα). Results Activation of the EGFR was found in a substantial number of tumors. Moreover, kidney tumors expressed elevated levels of TGFα. Down-regulation of EGFR or TGFα using RNAi or their pharmacological targeting with blocking antibodies resulted in inhibition of the proliferation of in vitro cellular models of renal cancer. Importantly, differences in the molecular forms of TGFα expressed by tumors and normal tissues were found. In fact, tumor TGFα was membrane anchored, while that expressed by normal kidney tissue was proteolytically processed. Conclusions The EGFR-TGFα axis plays a relevant role in the pathophysiology of kidney cancer. This study unveils a distinctive feature in renal cell carcinomas, which is the presence of membrane-anchored TGFα. That characteristic could be exploited therapeutically to act on tumors expressing transmembrane TGFα, for example, with antibody drug conjugates that could recognize the extracellular region of that protein.

Abstract Background Although the anti-HER2 antibody trastuzumab augments patient survival in HER2+ breast cancer, a relevant number of patients progress to this treatment. In this context, novel drug combinations are needed to increase its antitumor activity. In this work, we have evaluated the efficacy of proteolysis targeting chimera (PROTAC) compounds based on BET inhibitors (BETi) to augment the activity of trastuzumab in HER2+ breast cancer models. Methods BT474 and SKBR3 HER2+ breast cancer cell lines were used. The effects of trastuzumab and the BET-PROTAC MZ1 either alone or in combination, were evaluated using MTT proliferation assays, three-dimensional invasion and adhesion cultures, flow cytometry, qPCR and Western blot. In vivo studies were carried out in a xenografted model in mice. Finally, a Clariom_S_Human transcriptomic array was applied to identify deregulated genes after treatments. Results MZ1 induced a higher antiproliferative effect compared to the BETi JQ1. The combination of MZ1 and -trastuzumab significantly decreased cell proliferation, the formation of three-dimensional structures and cellular invasion compared to either of the drugs alone. Evaluation of apoptosis resulted in an increase of cell death following treatment with the combination, and biochemical studies displayed modifications of apoptosis and DNA damage components. In vivo administration of agents alone or combined, to tumors orthotopically xenografted in mice, resulted in a decrease of the tumor volume only after MZ1-Trastuzumab combination treatment. Results from a transcriptomic array indicated a series of newly described transcription factors including HOXB7, MEIS2, TCERG1, and DNAJC2, that were associated to poor outcome in HER2+ breast cancer subtype and downregulated by the MZ1-trastuzumab combination. Conclusions We describe an active novel combination that includes the BET-PROTAC MZ1 and trastuzumab, in HER2+ tumors. Further studies should be performed to confirm these findings and pave the way for their future clinical development.

Chronic myelogenous leukemia (CML) is a hematological malignancy that highly depends on the BCR-ABL1/STAT5 signaling pathway for cell survival. First-line treatments for CML consist of tyrosine kinase inhibitors that efficiently target BCR-ABL1 activity. However, drug resistance and intolerance are still therapeutic limitations in Ph+ cells. Therefore, the development of new anti-CML drugs that exhibit alternative mechanisms to overcome these limitations is a desirable goal. In this work, the antitumoral activity of JKST6, a naphthoquinone-pyrone hybrid, was assessed in imatinib-sensitive and imatinib-resistant human CML cells. Live-cell imaging analysis revealed JKST6 potent antiproliferative activity in 2D and 3D CML cultures. JKST6 provoked cell increase in the subG1 phase along with a reduction in the G0/G1 phase and altered the expression of key proteins involved in the control of mitosis and DNA damage. Rapid increases in Annexin V staining and activation/cleavage of caspases 8, 9 and 3 were observed after JKST6 treatment in CML cells. Of interest, JKST6 inhibited BCR-ABL1/STAT5 signaling through oncokinase downregulation that was preceded by rapid polyubiquitination. In addition, JKST6 caused a transient increase in JNK and AKT phosphorylation, whereas the phosphorylation of P38-MAPK and Src was reduced. Combinatory treatment unveiled synergistic effects between imatinib and JKST6. Notably, JKST6 maintained its antitumor efficacy in BCR-ABL1-T315I-positive cells and CML cells that overexpress BCR-ABL and even restored imatinib efficacy after a short exposure time. These findings, together with the observed low toxicity of JKST6, reveal a novel multikinase modulator that might overcome the limitations of BCR-ABL1 inhibitors in CML therapy.

The evolutionary relationships of Salvia have been difficult to estimate. In this study, we used the Next Generation Sequencing method Hyb-Seq to evaluate relationships among 90 Lamiaceae samples, including representatives of Mentheae, Ocimeae, Salvia subgenera Audibertia, Leonia, Salvia, and 69 species of subgenus Calosphace, representing 32 of Epling's sections. A bait set was designed in MarkerMiner using available transcriptome data to enrich 119 variable nuclear loci. Nuclear and chloroplast loci were assembled with hybphylomaker (HPM), followed by coalescent approach analyses for nuclear data (ASTRAL, BEAST) and a concatenated Maximum Likelihood analysis of chloroplast loci. The HPM assembly had an average of 1,314,368 mapped reads for the sample and 527 putative exons. Phylogenetic inferences resolved strongly supported relationships for the deep-level nodes, agreeing with previous hypotheses which assumed that subgenus Audibertia is sister to subgenus Calosphace. Within subgenus Calosphace, we recovered eight monophyletic sections sensu Epling, Cardinalis, Hastatae, Incarnatae, and Uricae in all the analyses (nDNA and cpDNA), Biflorae, Lavanduloideae, and Sigmoideae in nuclear analyses (ASTRAL, BEAST) and Curtiflorae in ASTRAL trees. Network analysis supports deep node relationships, some of the main clades, and recovers reticulation within the core Calosphace. The chloroplast phylogeny resolved deep nodes and four monophyletic Calosphace sections. Placement of S. axillaris is distinct in nuclear evidence and chloroplast, as sister to the rest of the S. subg. Calosphace in chloroplast and a clade with “Hastatae clade” sister to the rest of the subgenus in nuclear evidence. We also tested the monophyly of S. hispanica, S. polystachia, S. purpurea, and S. tiliifolia, including two samples of each, and found that S. hispanica and S. purpurea are monophyletic. Our baits can be used in future studies of Lamiaceae phylogeny to estimate relationships between genera and among species. In this study, we presented a Hyb-Seq phylogeny for complex, recently diverged Salvia, which could be implemented in other Lamiaceae.

El Real Decreto 865/2003 para la prevención y control de la legionelosis menciona el método de cultivo de la norma ISO 11731 para el ensayo de Legionella spp., norma en torno a la cual, se definen límites paramétricos. Las debilidades observadas en esta ISO (falsos negativos y elevados tiempos de espera), han hecho necesario buscar métodos alternativos. Se estudia si el método de separación inmunomagnética y cuantificación por colorimetría de Legionella spp., Legipid ® Legionella Fast Detection, (SIM), es adecuado y eficiente en un laboratorio oficial de Salud Pública para muestras ambientales de agua. En ausencia de una metodología normalizada para verificar métodos alternativos, se ha diseñado un método para realizar esta verificación, teniendo en cuenta los criterios específicos para análisis microbiológicos y la guía para kits de ensayo de ENAC. Así, se han calculado los parámetros de precisión y recuperación en las muestras inoculadas y, además, la linealidad a partir de la pendiente y la ordenada en el origen de la relación entre absorbancia y unidades formadoras de colonias, comparando los datos experimentales obtenidos con los resultados de la validación del método. Los resultados fueron satisfactorios en todos los casos. Una dispersión inferior al 20 %, una recuperación del 4 - 71 % y una linealidad conforme con la validación a un nivel de significación superior al 95 %. En base a estos resultados se considera que el método SIM es un método válido para la detección y cuantificación de Legionella spp. en un laboratorio oficial de salud pública.

Abstract Background Triple negative breast cancer (TNBC) is an incurable disease where novel therapeutic strategies are needed. Proteolysis targeting chimeric (PROTAC) are novel compounds that promote protein degradation by binding to an ubiquitin ligase. In this work, we explored the antitumoral activity of two novel BET-PROTACs, MZ1 and ARV-825, in TNBC, ovarian cancer and in a BET inhibitor resistant model. Methods OVCAR3, SKOV3, BT549, MDA-MB-231 cell lines and the JQ1 resistant cell line MDA-MB-231R were evaluated. MTTs, colony-forming assay, three-dimensional cultures in matrigel, flow cytometry, and western blots were performed to explore the anti-proliferative effect and biochemical mechanism of action of MZ1 and ARV-825. In vivo studies included BALB/c nu/nu mice engrafted with MDA-MB-231R cells. Results The BET-PROTACs MZ1 and ARV-825 efficiently downregulated the protein expression levels of the BET protein BRD4, in MDA-MB-231 and MDA-MB-231R. MZ1 and ARV-825 also showed an antiproliferative effect on sensitive and resistant cells. This effect was corroborated in other triple negative (BT549) and ovarian cancer (SKOV3, OVCAR3) cell lines. MZ1 provoked G2/M arrest in MDA-MB-231. In addition, a profound effect on caspase-dependent apoptosis was observed in both sensitive and resistant cells. No synergistic activity was observed when it was combined with docetaxel, cisplatin or olaparib. Finally, in vivo administration of MZ1 rescued tumor growth in a JQ1-resistant xenograft model, reducing the expression levels of BRD4. Conclusions Using both in vitro and in vivo approaches, we describe the profound activity of BET-PROTACs in parental and BETi-resistant TNBC models. This data provides options for further clinical development of these agents in TNBC.

A ready-to-eat cereal processed by a twin-screw extrusion was formulated, using flour and bran from a quality protein maize (QPM) variety and a zinc biofortified rice. The effect of variation of the content of bran in the formulation on the physical quality of the extruded product was studied. The maize-rice meal mixtures contained rice and maize bran formulated at two levels, 25 and 30 % of the total; within the bran mixture the rice bran content was formulated at levels ranging from 0 to 10 %. Physical characteristics of the extrudates such as expansion ratio (ER) and crispness work indicator (WC), were determined. The treatments with lower content of rice bran showed a better behavior, in terms of the physical variables. The products with higher ER and lower WC had desirable sensorial characteristics. Analysis of the extrudates confirmed an increased content of Zn, lysine, tryptophan in relation to raw materials.

This research studied the prevention of hydrolytic rancidity during the storage of rice bran stabilized by an extrusion process. A double screw extruder was used, set at 130° C in the barrel and a rotational speed of the screws programmed at 200 RPM. The moisture content of the bran was adjusted at 20%. The treated bran was stored, using two packing methods (with and without vacuum), at two ambient conditions (18° C – 70 % RH and 30° C - 78% RH) for a period of 8 weeks. The content of free fatty acids (FFA) in the rice bran was observed during the storage time period. The extruded treated rice bran stored at 18° C - 70% RH resulted in lower values of FFA in comparison with the values in the bran kept at 30° C - 78% RH. Vacuum packaging showed a significant disadvantage as compared to packaging without vacuum.

The large flood pulse of the Amazon basin is a principal driver of environmental heterogeneity with important implications for ecosystem function and the assembly of natural communities. Understanding species ecological response to the flood pulse is thus a key question with implications for theories of species coexistence, resource management, and conservation. Yet these remain largely undescribed for most species, and in particular for trees. The large flood pulse and high tree diversity of the Negro River floodplain makes it an ideal system to begin filling this knowledge gap. We merged historical hydrologic data with 41 forest inventories under variable flooding conditions distributed across the Negro River basin, comprising a total area of 34 ha, to (i) assess the importance of flood duration as a driver of compositional variation, (ii) model the response curve shapes of 111 of the most frequent tree species in function of flood duration, and (iii) derive their niche properties (optima and tolerance). We found that flood duration is a strong driver of compositional turnover, although the majority site-to-site variation in forest composition still remains unexplained. About 73% of species responded to the flood duration gradient, exhibiting a diversity of shapes, but most frequently skewed. About 29% of species were clearly favored by flood durations >120 days year–1, and 44% of species favored by shorter floods. The median niche breadth was 85 flood days year–1, corresponding to approximately 30% of the flood duration gradient. A significant subset of species (27%) did not respond to flooding, but rather exhibited wide tolerance to the flood gradient. The response models provided here offer valuable information regarding tree species differential capacity to grow, survive, and regenerate along an ecologically important gradient and are spatially valid for the Amazon Negro basin. These attributes make them an appealing tool with wide applicability for field and experimental studies in the region, as well as for vegetation monitoring and simulation models of floodplain forest change in the face of hydrologic alteration.

Este artículo se propone identificar las ansiedades políticas, sociales y económicas que animaron a las élites seculares de Anglia Oriental —en los albores del siglo XIV— en la comisión de libros devocionales privados cuya marginalia incluía los novedosos y recurrentes temas del clérigo y el obispo monstruosos. Poniendo en diálogo las fuentes documentales producidas durante el período con la estrecha relación que se teje entre el texto de los salterios y la periferia visual que suele acompañarlos, este trabajo sugiere que el obispo y el clérigo monstruosos representaban el malestar de los señores de Anglia Oriental frente al Papado de Aviñón y las crisis disciplinares que enfrentó el clero inglés en los siglos XIII y XIV.

The neuregulins (NRGs) represent a large family of membrane‐anchored growth factors, whose deregulation may contribute to the pathogenesis of several tumors. In fact, targeting of NRG‐activated pathways has demonstrated clinical benefit. To improve the efficacy of anti‐NRG therapies, it is essential to gain insights into the regions of NRGs that favor their pro‐oncogenic properties. Here, we have addressed the protumorigenic impact of different NRG domains. To do this, deletion mutants affecting different NRG domains were expressed in 293 and MCF7 cells. Of the five forms studied, only the wild‐type and a mutant lacking the Ig‐like domain (NRGΔIg) were properly sorted to the plasma membrane. Both forms were released as soluble forms to the culture media. However, the mutant NRGΔIg failed to efficiently activate HER2 and HER3 receptors, signaling pathways, and cell proliferation when compared to wild‐type NRG. Treatment with trastuzumab, a humanized antibody used in the breast cancer clinic, inhibited the constitutive activation of HER2, HER3, and downstream signaling in MCF7 cells constitutively expressing wild‐type NRG. In contrast, this treatment had a marginal effect on MCF7‐NRGΔIg cells. This study demonstrates that the Ig‐like region of NRGs exerts an important role in their capability to activate ErbB/HER receptors and mitogenic responses. Strategies aimed at targeting NRGs should consider that fact to improve neutralization of the pro‐oncogenic properties of NRGs.

Metastatic dissemination of tumor cells is responsible for the fatal outcome of breast cancer. Therefore, understanding the mechanisms involved in dissemination is essential for the development of new therapeutic strategies to prevent metastasis. One mechanism involved in metastatic dissemination of breast cancer cells is dependent on control of the production of matrix metalloproteinases by the neuregulins (NRGs). The NRGs are polypeptide factors that act by binding to the ErbB/HER subfamily of receptor tyrosine kinases. NRG‐mediated activation of HER receptors causes an increase in the production of metalloprotease 13 (MMP13, also termed collagenase‐3), which facilitates metastatic dissemination of breast tumors. In this context, we aimed to explore whether the clinically approved tyrosine kinase inhibitor dasatinib was able to neutralize this mechanism of metastatic dissemination. Here, we show that dasatinib restricted NRG‐induced MMP13 upregulation, both in vitro and in vivo, and in vivo metastatic dissemination of breast cancer cells. Chemical proteomics studies showed that the main cellular targets of dasatinib were SRC family kinases (SFKs). Moreover, genetic studies showed that knockdown of SRC or YES strongly inhibited NRG‐induced MMP13 upregulation in vitro. Mechanistically, dasatinib treatment or knockdown of SRC also inhibited ERK1/2 kinases in vitro, which were required for NRG‐induced MMP13 upregulation. These results open the possibility of clinically exploring the antitumoral action of dasatinib in those tumors in which the NRG–MMP13 signaling axis may play a relevant role in the control of tumor cell dissemination.

The goal of this study was the identification of mycorrhizal fungi associated with three terrestrial orchids of the genus Bletia Ruiz & Pav.: B. roezlii Rchb. f., B. purpurata A.Rich., and B. punctata Lex., in Barranca del Cupatitzio Natural Reserve - Michoacán, México - . Thirty-nine strains were isolated and morphologically characterized. Nine strains were selected from the molecular analysis. Bletia punctata, an endemic species of Mexico, showed the lowest variability in mycorrhizal fungi. Morphological analysis showed that 39 isolated strains belong to the ‘Rhizoctonia-like fungal complex’. According with the tree of Euclidian distances generated by the analysis WARD, all isolates were included into four subgroups, all related to the genus Tulasnella J.Schröt - which belongs to the ‘Rhizoctonia-like fungal complex’?. Molecular and phylogenetic analysis of the nine selected strains corroborated the results of the morphological study: the sequences obtained were clustered in four subclades related to species of Tulasnella. Our results indicate that a single species of Bletia from a single locality can be associated with different species of mycorrhizal fungi, at least during the adult stage and that the combination of morphological and molecular analyses is a good tool to identify orchid mycorrhizal fungi.

Antecedentes: El ritmo de las estimaciones de riesgo de extinción es lento en relación con la magnitud del problema. En el caso de las plantas se han evaluado el 6 % de las especies. Por otro lado, se ha determinado que la extensión del área de distribución es un buen predictor del riesgo de extinción. Preguntas: ¿Se puede agilizar la estimación de riesgo de extinción de las especies vegetales? ¿Estimaciones de riesgo tomando en cuenta sólo el área de distribución, pueden convergir con estimaciones de métodos ya establecidos? Taxon: Peltogyne mexicana Sitio de estudio: Guerrero, México Métodos: Se implementó la Evaluación para Asignar Tentativamente Riesgo de Extinción (ETRE) comparando el área de ocupación (AOO) del árbol tropical maderable Peltogyne mexicana contra el AOO de otras leguminosas arbóreas con estatus de riesgo de extinción ya establecidos. Se implementó el Método de Evaluación de Especies en Riesgo (MER) y se compararon los resultados. Resultados: Con la implementación de la ETRE se determinó que el árbol tropical maderable Peltogyne mexicana se encuentra en peligro de extinción, lo cual se confirma con la implementación del MER. Discusión: La idoneidad de la ETRE se basa en que varios predictores del riesgo de extinción están supeditados al tamaño del área de distribución y a que la estimación de ésta última es ampliamente aceptada por medio del AOO. La ETRE es un procedimiento objetivo y fácilmente replicable, que se puede implementar previamente a evaluaciones más escrupulosas, como el MER. Se proponen acciones para evitar la pérdida de Peltogyne mexicana.

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Wetlands harbor an important compliment of regional plant diversity, but in many regions data on wetland diversity and composition is still lacking, thus hindering our understanding of the processes that control it. While patterns of broad-scale terrestrial diversity and composition typically correlate with contemporary climate it is not clear to what extent patterns in wetlands are complimentary, or conflicting. To elucidate this, we consolidate data from wetland forest inventories in Brazil and examine patterns of diversity and composition along temperature and rainfall gradients spanning five biomes. We collated 196 floristic inventories covering an area >220 ha and including >260,000 woody individuals. We detected a total of 2,453 tree species, with the Amazon alone accounting for nearly half. Compositional patterns indicated differences in freshwater wetland floras among Brazilian biomes, although biomes with drier, more seasonal climates tended to have a larger proportion of more widely distributed species. Maximal alpha diversity increased with annual temperature, rainfall, and decreasing seasonality, patterns broadly consistent with upland vegetation communities. However, alpha diversity-climate relationships were only revealed at higher diversity values associated with the uppermost quantiles, and in most sites diversity varied irrespective of climate. Likewise, mean biome-level differences in alpha-diversity were unexpectedly modest, even in comparisons of savanna-area wetlands to those of nearby forested regions. We describe attenuated wetland climate-diversity relationships as a shifting balance of local and regional effects on species recruitment. Locally, excessive waterlogging strongly filters species able to colonize from regional pools. On the other hand, increased water availability can accommodate a rich community of drought-sensitive immigrant species that are able to track buffered wetland microclimates. We argue that environmental conditions in many wetlands are not homogeneous with respect to regional climate, and that responses of wetland tree communities to future climate change may lag behind that of non-wetland, terrestrial habitat.

Fundamentos: en los últimos años se ha evidenciado la presencia de nuevos contaminantes en el agua, existiendo pocos estudios que analicen dicha presencia. Los objetivos fueron determinar drogas de abuso (DAs) y sus metabolitos en el influente y efluente de la Estación Depuradora de Aguas Residuales (EDAR) de Talavera de la Reina y en el río Tajo, evaluar el rendimiento de la EDAR en la eliminación de estas sustancias y estimar el consumo de drogas en la ciudad de Talavera. Métodos: el muestreo fue realizado, el día 28 de Junio de 2010. En todas las muestras se analizaron 5 grupos de drogas (10 DAs y 9 metabolitos). Se calculó el rendimiento a partir del porcentaje de reducción de la concentración a la entrada y salida de la EDAR y el consumo de drogas a partir de las concentraciones del influente y utilizando una metodología específica, basada en la asunción de que las drogas después de ser consumidas y metabolizadas en el cuerpo humano, son excretadas como compuestos principales o metabolitos, cuyas rutas metabólicas son conocidas; y que la cantidad de droga o metabolito cuantificado corresponde con la dosis consumida. Resultados: se detectaron 10 sustancias. La presencia de Benzoiclegonina (BE) (metabolito de la cocaína), efedrina, y metadona junto su metabolito EDDP fue hallada en todas las muestras. Las mayores concentraciones fueron de BE (239 ng/L), y de THC- COOH (35 ng/L), ambas en influente. En el río Tajo las concentraciones mas altas fueron de BE (5,38 ng/L) y EDDP (4,4 ng/L). El rendimiento de la EDAR fue mayor del 80% para todas las sustancias excepto para metadona (que fue nulo) y EDDP (con mayor concentración en el efluente de la EDAR). Las sustancias más consumidas fueron cannabis (THC) (1,88 g/día) y cocaína (0,46 g/día). Conclusiones: SSe detectó la presencia de DAs en el río Tajo a su paso por Talavera de la Reina, lo que evidencia que estas sustancias no son eliminadas totalmente por la EDAR. El consumo de drogas estimado indica que la población de Talavera consume principalmente cannabis y cocaína. Demostrando que esta metodología puede complementar las encuestas sobre consumo de drogas.

El punto de partida de este artículo es la consideración de que el concepto de seguridad trasciende a la seguridad pública. Con el objetivo de identificar su significado en la normatividad mexicana, que está restringido a la seguridad pública, aquí se analizan sus definiciones en el marco legal del gobierno federal y de las entidades federativas. En el primero, el significado se amplía al de seguridad nacional, pero limita la cooperación intergubernamental, en contraparte, las entidades carecen de un concepto equivalente, lo que impide incorporar en su agenda asuntos diversos relacionados con la materia. La propuesta aquí es incluir a la seguridad interior, de tal forma que permita tanto la colaboración dentro del gobierno como la intergubernamental, así como de otros temas en la agenda, que trasciendan a la seguridad pública.

Los bosques de pino-encino de la comunidad de Nuevo San Juan, Michoacán, están dominados por Pinus pseudostrobus, P. devoniana y P. leiophylla. Los patrones de variación genética de estas especies no se conocen lo suficiente, particularmente los de P. leiophylla, lo cual limita la creación de lineamientos para el movimiento de semillas y plántulas para reforestación y su adaptación al cambio climático. Las especies se recolectaron en cuatro o cinco procedencias a lo largo de un transecto altitudinal (1,650 a 2,500 m) para el establecimiento de un ensayo en vivero, con el objetivo de cuantificar la variación genética entre y dentro de las especies. La altura de la planta (tres y cinco meses de edad) fue significativamente diferente (P < 0.0001) entre especies. Entre procedencias hubo diferencias significativas para P. devoniana (P < 0.0001) y P. leiophylla (P = 0.0352). La especie P. devoniana mostró un pronunciado patrón de crecimiento asociado con la altitud de origen, donde las plantas con mayor crecimiento procedían de una menor altitud. Las poblaciones de P. leiophylla fueron diferentes sólo a los tres meses de edad, sin un patrón altitudinal estadísticamente significativo. No se encontraron diferencias significativas entre poblaciones de P. pseudostrobus.

El artículo constituye una propuesta para definir con claridad el significado de gobernabilidad. Para ello, se propone considerarla como una categoría conceptual para el análisis político incorporando elementos tanto del régimen político como del de políticas públicas. La propuesta relaciona y diferencia la definición de gobernabilidad con conceptos como estabilidad, orden, crisis, gobernanza y buen gobierno.

Se revisa la distribución de Cestrum mortonianum y se describe e ilustra una variedad de la Sierra de Manantlán. Se discuten las características que la diferencian de C. mortonianum var. mortonianum, C. tomentosum y C. pacificum, las cuales tienen en común la presencia de pubescencia ramificada. Se proporciona una clave para separar las especies de Cestrum de México con este tipo de indumento.

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Objetivos: Determinar la evolución y la distribución geográfica de la temperatura umbral de disparo de la mortalidad por extremos térmicos en Castilla-La Mancha entre 1975 y 2003. Métodos: El análisis se divide en tres periodos (1975-1984, 1985-1994 y 1995-2003) para cada provincia de la región. Se modeliza la mortalidad diaria por causas orgánicas (variable dependiente) utilizando procedimientos ARIMA. Los residuos diarios de mortalidad resultantes se relacionan con las temperaturas máximas diarias agrupadas en intervalos de 2ºC, obteniendo una temperatura umbral por frío o por calor si esos residuos aumentan de forma significativa (pObjectives: To determine time trends and the geographical distribution of mortality trigger temperature thresholds due to extreme temperatures in Castile-La Mancha (central Spain) between 1975 and 2003. Methods: The analysis was divided into three periods (1975-1984, 1985-1994 and 1995-2003) for each province of the region. Daily mortality due to organic causes (dependent variable) was modelled using autoregressive integrated moving average (ARIMA) procedures. The resulting residual series was related to the maximum temperature series grouped in 2ºC intervals to obtain a threshold temperature for cold or heat when the residuals rose significantly (p

En el verano de 2003 las temperaturas alcanzadas fueron responsables de un gran número de muertes en el continente europeo. Un año después muchos países habían implantado algún tipo de plan de prevención frente al exceso de temperaturas. Planes que ya habían mostrado su capacidad de prevenir una buena parte de la mortalidad evitable en otras latitudes. Desde entonces, son numerosos los estudios publicados ofreciendo nuevos datos sobre los efectos en salud pública de una ola de calor, que pueden contribuir a aumentar la eficiencia de estos planes de prevención. Conocer las situaciones meteorológicas de mayor riesgo, definir ola de calor o tener en cuenta el tiempo que el plan debe estar activo a partir del estudio de la relación entre la temperatura y sus efectos en salud, identificar las características meteorológicas que modulan la relación entre la temperatura y la mortalidad, localizar el perfil de las personas de mayor riesgo o diseñar protocolos de actuación con la mayor precisión posible y basado en el conocimiento científico son elementos extraídos de numerosos trabajos realizados en los últimos años que deben ser tenidos en cuenta.

Se presenta el caso clínico de una mujer de 33 años con una leiomiomatosis peritoneal diseminada (LPD) diagnosticada durante cirugía por tumor anexial. Al siguiente año se embaraza. Durante la cesárea efectuada a las 38 semanas, se observa una exacerbación de la enfermedad con sospecha de malignización por lo que se efectúa una histerectomía total más salpingooforectomía bilateral y resección de sólo algunos nodulos de la cavidad abdominal. La biopsia diferida confirma el diagnóstico de LPD. A la fecha completó 8 años de seguimiento sin evidencias clínicas ni imágenes de persistencia.We report the clinical case of 33 years-old woman with leiomyomatosis peritonealis disseminata (LPD) whose diagnosis becomes evident during a surgery for adnexal tumor. The next year she gets pregnant. During the cesarean section performed at 38 weeks' gestation, it is observed a disease exacerbation with malignant characteristics. Because of that, a total hysterectomy takes place. It is performed a bilateral salpingo-oophorectomy and resection of only some nodules of the abdominal cavity. The deferred biopsy confirms the LPD diagnosis. By this time she has completed 8 years of clinical follow-up without clinical evidences or images of persistence.

Fundamento: La relación no lineal temperatura- mortalidad varía según las características de la zona geográfica estudiada. En determinados lugares un incremento en el nivel de desarrollo ha conducido a una menor influencia de las variables ambientales sobre la mortalidad. Se analiza la evolución entre 1975 y 2003 de la asociación de las temperaturas máximas con la mortalidad por causas orgánicas en Castilla-La Mancha. Métodos: Los datos diarios de temperaturas máximas y de mortalidad por causas orgánicas se dividen en tres periodos: 1975-1984, 1985-1994 y 1995-2003. Tras un preblanqueo de los datos aplicando el modelo ARIMA ajustado para las series de temperaturas, se calculan las funciones de correlación cruzada entre los residuos de las series de temperaturas y de mortalidad con 7 desfases en verano y 15 en invierno, comparándose los coeficientes de correlación. Resultados: Se observa en los meses calurosos un incremento del número de retardos significativos (p

Fundamento:Numerosos trabajos relacionan variables atmos-féricas con indicadores sanitarios. En regiones extensas, como Cas-tilla- La Mancha, puede ser necesario dividirla en áreas en función delas variables atmosféricas disponibles, eligiendo una estación mete-orológica representativa para cada zona. El objetivo de este artículoes analizar los datos diarios de temperaturas de numerosos observa-torios de Castilla- La Mancha y su reducción a unas pocas estacionesrepresentativas para ser utilizadas en estudios que relacionen varia-bles atmosféricas con indicadores sanitarios de esta región. Métodos:Se seleccionaron estaciones meteorológicas de Casti-lla- La Mancha en función del número de años disponibles y de datosperdidos. Tras rellenar las lagunas de las series elegidas, detectarposibles discontinuidades y homogeneizar las series, los datos dia-rios de temperaturas se utilizan en análisis de conglomerados jerár-quico y factorial mediante componentes principales. Resultados:El análisis factorial extrae un solo factor utilizandolas series de temperaturas máximas, medias o mínimas. En las máxi-mas, ese factor explica el 93,45% de la varianza, con autovalor39,249. La estación Toledo «Compuesta» tiene coeficientes decorrelación en la matriz de componentes principales de 0,987; 0,991y 0,981 para las series de temperaturas máximas, medias y mínimasrespectivamente. Conclusiones: Castilla-La Mancha es una región isoclimática enfunción de la temperatura y la estación Toledo «Compuesta» la ele-gida como representativa regional para estudios en salud pública.Los resultados permiten la realización de estudios desagregados enunidades menores como las provincias, con las estaciones de lascapitales administrativas como referencia.

Se presenta un caso de embarazo cornual complicado; se hace énfasis en el diagnóstico y manejo quirúrgico oportuno e importancia del cuadro clínico. Se describe la complicación de tromboembolismo pulmonar bilateral durante el post operatorioA case is presented of a complicated interstitial pregnancy. It is emphasized in the opportune diagnosis and treatment and the relevance of the clinic. In addition it is described the appearance of pulmonary embolism during the postoperative period

Este artículo parte del reconocimiento de la amenaza que implica el crimen organizado para un régimen democrático y analiza la política que, para combatirlo, se ha adoptado en México durante la gestión del presidente Felipe Calderón. Asimismo, se cuestiona si el gobierno considera este asunto como de seguridad pública o de seguridad nacional. El hallazgo principal revela que el objetivo del gobierno federal no es combatir el crimen organizado sino la violencia que éste genera, y que para ello ha implementado una política basada principalmente en el uso de la fuerza pública, factor que no facilita la colaboración inter e intragubernamental por los conflictos que surgen cuando se articulan las políticas de seguridad pública con las de seguridad nacional. Abstract This paper is based on the assumption that the organized crime is a menace for democracy. The article develops an analysis on the fight against organized crime's policy design in the Felipe Calderon's government, questioning if the policy is managed as a police's issue or a national security's issue. The main finding is the identification of the Mexican's government objective in the "war against organized crime" switching the focus from organized crime to the violence created by criminal organizations. To fight violence the government implements a policy based on the use of public force that doesn't consider the cooperation between different governmental agencies.

BACKGROUND: Breast cancer is the most common neoplasia in women. Even though advances in its treatment have improved disease outcome, some patients relapse. Therefore, attempts to better define the molecular determinants that drive breast cancer cell proliferation may help in defining potential therapeutic targets. Mitogen-activated protein kinases (MAPK) play important roles in tumorigenesis. One of them, Erk5, has been linked to the proliferation of breast cancer cells in vitro. Here we have investigated the expression and prognostic value of Erk5 in human breast cancer. METHODOLOGY/PRINCIPAL FINDINGS: Animal and cellular models were used to study Erk5 expression and function in breast cancer. In 84 human breast tumours the expression of Erk5 was analyzed by immunohistochemistry. Active Erk5 (pErk5) was studied by Western blotting. Correlation of Erk5 with clinicopathological parameters and with disease-free survival in early stage breast cancer patients was analyzed. Expression of Erk5 was detected in most patients, and overexpression was found in 20%. Active Erk5 was present in a substantial number of samples, as well as in tumours from an animal breast cancer model. Overexpression of Erk5 was associated with a decrease in disease-free survival time, which was independent of other clinicopathological parameters of prognosis. Transient transfection of a short hairpin RNA (shRNA) targeting Erk5, and a stable cell line expressing a dominant negative form of Erk5 (Erk5(AEF)), were used to investigate the influence of Erk5 on drugs used in the clinic to treat breast tumours. We found that inhibition of Erk5 decreased cancer cell proliferation and also sensitized these cells to the action of anti-HER2 therapies. CONCLUSIONS/SIGNIFICANCE: Overexpression of Erk5 is an independent predictor of disease-free survival in breast cancer, and may represent a future therapeutic target.

Background c-Kit is expressed in the plasma cells from 30% of patients with multiple myeloma. Two different isoforms of c-Kit, characterized by the presence or absence of the tetrapeptide sequence GNNK in the extracellular domain, have been described. However, their expression and function in myeloma cells are unknown.We explored the function and expression of these c-Kit isoforms in myeloma cells.Design and Methods Expression of c-Kit isoforms was investigated by reverse transcriptase polymerase chain reaction in fresh plasma cells from patients and cell lines. The function of these c-Kit isoforms was analyzed upon expression in myeloma cells. Signaling was investigated by western blotting using antibodies specific for activated forms of several signaling proteins. The impact of c-Kit on the action of drugs commonly used in the treatment of multiple myeloma was investigated by MTT proliferation assays.Results Fresh plasma cells from patients as well as myeloma cell lines expressed the two isoforms of c-Kit. Retroviral infection of myeloma cells with vectors that code for c-Kit-GNNK+ or c-Kit-GNNK− forms demonstrated differences in the kinetics of phosphorylation between these isoforms. Stem cell factor-induced activation of the GNNK− form was faster and more pronounced than that of the GNNK+ form, whose activation, however, lasted for longer. The c-Kit receptors weakly activated the Erk1/2 and Erk5 pathways. Both receptors, however, efficiently coupled to the PI3K/Akt pathway, and stimulated p70S6K activation. The latter was sensitive to the mTOR inhibitor, rapamycin. Studies of drug sensitivity indicated that cells expressing the GNNK− form were more resistant to the anti-myeloma action of bortezomib and melphalan.Conclusions Our data indicate that c-Kit expression in multiple myeloma cells is functional, and coupled to survival pathways that may modulate cell death in response to therapeutic compounds used in the treatment of this disease.

Background Proteasome inhibition represents a promising novel anticancer therapy, and bortezomib is a highly selective reversible inhibitor of the proteasome complex. Acute myeloid leukemia (AML) is an immnunophenotypically heterogeneous group of diseases, with CD34+ cases being associated with drug resistance and poor outcome. We investigated the effects of bortezomib on the growth and survival of AML cells.Design and Methods We studied the in vitro activity and mechanism of action of bortezomib on both cell lines and fresh cells from 28 AML patients including CD34+ and CD34− cases.Results Bortezomib showed potent anti-AML activity (IC50 < 50 nM), which was greater than that of conventional agents (doxorubicin, cytarabine and fludarabine). Moreover, synergistic effects were observed when bortezomib was adminstered in combination with doxorubicin and cytarabine. Mechanistically, bortezomib induced accumulation of cells in the G2/M phase, with up-regulation of p27, together with cell death through an increase in the mitochondrial outer membrane permeability involving caspase-dependent and -independent pathways. The apoptotic activity of bortezomib on fresh CD34+ blast cells from patients was similar to that observed on CD34−blast cells. Importantly, bortezomib was significantly more active than doxorubicin in the immature CD34+ cells, while there were no differences in its action on CD34− cells.Conclusions Bortezomib induces apoptosis in acute myeloid leukemia cells in vitro. Whether this drug might be useful in the treatment of patients with acute myeloid leukemia can be established only in ad hoc clinical trials.