Real-life analysis on safety and efficacy of asciminib for ponatinib pretreated patients with chronic myeloid leukemia.

Failure of second-generation tyrosine kinase inhibitors (2GTKI) is a challenging situation in patients with chronic myeloid leukemia (CML). Asciminib, recently approved by the US Federal Drug Administration, has demonstrated in clinical trials a good efficacy and safety profile after failure of 2GTKI. However, no study has specifically addressed response rates to asciminib in ponatinib pretreated patients (PPT). Here, we present data on responses to asciminib from 52 patients in clinical practice, 20 of them (38%) with prior ponatinib exposure. We analyzed retrospectively responses and toxicities under asciminib and compared results between PPT and non-PPT patients.After a median follow-up of 30 months, 34 patients (65%) switched to asciminib due to intolerance and 18 (35%) due to resistance to prior TKIs. Forty-six patients (88%) had received at least 3 prior TKIs. Regarding responses, complete cytogenetic response was achieved or maintained in 74% and 53% for non-PPT and PPT patients, respectively. Deeper responses such as major molecular response and molecular response 4.5 were achieved in 65% and 19% in non-PPT versus 32% and 11% in PPT, respectively. Two patients (4%) harbored the T315I mutation, both PPT.In terms of toxicities, non-PPT displayed 22% grade 3-4 TEAE versus 20% in PPT. Four patients (20% of PPT) suffered from cross-intolerance with asciminib as they did under ponatinib.Our data supports asciminib as a promising alternative in resistant and intolerant non-PPT patients, as well as in intolerant PPT patients; the resistant PPT subset remains as a challenging group in need of further therapeutic options.

Primer consenso cubano sobre el uso de terapia convencional y biológica en pacientes con artritis reumatoide / First Cuban consensus on the use of conventional and biological therapy in patients with rheumatoid arthritis

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Introduction: The development of recommendations for the treatment of rheumatoid arthritis (RA) in the Cuban context may be one of the ways to achieve better control of this disease. Objective: To reach a consensus and update relevant aspects of conventional and biological RA modifier therapy in Cuba. Methods: 18 specialists from 8 Cuban provinces, experts in RA care, were summoned, according to the years of dedication to the specialty, the conferences on this topic and their publications. The first meeting took place in March 2016 in the provincial hospital of Villa Clara, Cuba, with the participation of all the experts. A review of the literature on conventional and biological therapy previously collected by the participants was developed, and two teams were formed: the first would address everything related to conventional therapy in RA (HRCT) and the other, biological therapy in RA (TBAR). Three questionnaires related to the use of corticosteroids, HRCT and TBAR, were prepared, answered by the participants via email. In a second meeting, held in October 2016 in Havana, the analysis of all the responses provided was carried out. Questions with a response of 90% or more votes were considered as recommendations. Results: The questionnaires were answered by 95% of the participants. 9 recommendations and 1 algorithm were established. The recommendations are as follows: methotrexate is the drug of choice in the treatment of RA after diagnosis; The administration of another conventional drug (DMARDc) (azathioprine, salazosulfapyridine, antimalarials and leflunomide) is recommended in patients with a diagnosis of active RA in whom methotrexate is contraindicated or there is a failure in response - consider the administration of low doses of prednisone or equivalent (<7.5 mg/d) associated with DMARDc in patients with active moderate to severe RA, for the shortest possible time; perform serological control including tests for hepatitis B and C viruses and screening for HIV in all patients diagnosed with RA before starting treatment with DMARDc and biologics; in patients in remission or, at least, with a DAS-28 below 3.2, consideration should be given to withdrawing one of the DMARDs or reducing, to the minimum possible expression, the dose of both disease modifiers; if methotrexate fails, tocilizumab in combination with methotrexate or as monotherapy will be indicated. Conclusions: Aspects related to conventional therapy with methotrexate, azathioprine, salazosulfapyridine, antimalarials and leflunomide were agreed. The value of early diagnosis and immediate initiation of DMARDc therapy and the use of glucocorticoids was analyzed. Treatment with tocilizumab, the only biological available in Cuba against RA, will be administered when there is a failure in the response to conventional therapy and combinations between these drugs. It is recommended to hold educational conferences through the mass media aimed at patientshttp(AU)

Defining MAP3 kinases required for MDA-MB-231 cell tumor growth and metastasis.

Analysis of patient tumors suggests that multiple MAP3 kinases (MAP3Ks) are critical for growth and metastasis of cancer cells. MAP3Ks selectively control the activation of extracellular signal-regulated kinase 1/2 (ERK1/2), Jun N-terminal kinase (JNK), p38 and ERK5 in response to receptor tyrosine kinases and GTPases. We used MDA-MB-231 cells because of their ability to metastasize from the breast fat pad to distant lymph nodes for an orthotopic xenograft model to screen the function of seven MAP3Ks in controlling tumor growth and metastasis. Stable short hairpin RNA (shRNA) knockdown was used to inhibit the expression of each of the seven MAP3Ks, which were selected for their differential regulation of the MAPK network. The screen identified two MAP3Ks, MEKK2 and MLK3, whose shRNA knockdown caused significant inhibition of both tumor growth and metastasis. Neither MEKK2 nor MLK3 have been previously shown to regulate tumor growth and metastasis in vivo. These results demonstrated that MAP3Ks, which differentially activate JNK, p38 and ERK5, are necessary for xenograft tumor growth and metastasis of MDA-MB-231 tumors. The requirement for MAP3Ks signaling through multiple MAPK pathways explains why several members of the MAPK network are activated in cancer. MEKK2 was required for epidermal growth factor receptor and Her2/Neu activation of ERK5, with ERK5 being required for metastasis. Loss of MLK3 expression increased mitotic infidelity and apoptosis in vitro. Knockdown of MEKK2 and MLK3 resulted in increased apoptosis in orthotopic xenografts relative to control tumors in mice, inhibiting both tumor growth and metastasis; MEKK2 and MLK3 represent untargeted kinases in tumor biology for potential therapeutic development.

Changes in visceral flow induced by laparoscopic and open living-donor nephrectomy: experimental model.

Increased intra-abdominal pressure during laparoscopy changes visceral flow. The objective of the present study was to analyze the changes in peripheral and intra-abdominal flow induced by laparoscopic living-donor nephrectomy in an experimental model. Twenty pigs underwent left-sided nephrectomy, 10 at laparoscopy and 10 in an open approach. Renal blood flow (RBF), hepatic arterial flow (HAF), portal flow (PF), and carotid flow (CF) were measured using an electromagnetic probe placed around these vessels. Comparative analysis between the groups demonstrated increased CF (mean [SD], 125.73 [41.69] vs 291.70 [51.52] mL/min; P < .001) and decreased PF (973.67 [131.70] vs 546.83 [217.53] mL/min; P = .001) and HAF (278.00 [94.71] vs 133.33 [112.32] mL/min; P = .03) in pigs that underwent laparoscopy compared with those who underwent open surgery; no significant differences were observed in RBF. In conclusion, laparoscopic nephrectomy induces increased CF and decreased total hepatic flow, at the expense of PF and HAF. With adequate intravascular volume expansion, no differences were observed in RBF between the laparoscopic and open approaches.

Mutations in rpoB and katG genes in Mycobacterium isolates from the Southeast of Mexico.

The most frequent mutations associated with rifampin and isoniazid resistance in Mycobacterium are the substitutions at codons 531 and 315 in the rpoB and katG genes, respectively. Hence, the aim of this study was to characterize these mutations in Mycobacterium isolates from patients suspected to be infected with drug-resistant (DR) pulmonary tuberculosis (TB) in Veracruz, Mexico. Drug susceptibility testing of 25 clinical isolates revealed that five were susceptible while 20 (80%) were DR (15% of the annual prevalence for Veracruz). Of the DR isolates, 15 (75%) were resistant to rifampin, 17 (85%) to isoniazid and 15 (75%) were resistant to both drugs (MDR). Sequencing analysis performed in the isolates showed that 14 (93%) had mutations in the rpoB gene; seven of these (47%) exhibited a mutation at 531 (S-->L). Ten (58%) of the 20 resistant isolates showed mutations in katG; nine (52%) of these 10 exhibited a mutation at 315 (S-->T). In conclusion, the DR profile of the isolates suggests a significant number of different DR-TB strains with a low frequency of mutation at codons 531 and 315 in rpoB and katG, respectively. This result leads us to consider different regions of the same genes, as well as other genes for further analysis, which is important if a genetic-based diagnosis of DR-TB is to be developed for this region.

Mutations in rpoB and katG genes in Mycobacterium isolates from the Southeast of Mexico

The most frequent mutations associated with rifampin and isoniazid resistance in Mycobacterium are the substitutions at codons 531 and 315 in the rpoB and katG genes, respectively. Hence, the aim of this study was to characterize these mutations in Mycobacterium isolates from patients suspected to be infected with drug-resistant (DR) pulmonary tuberculosis (TB) in Veracruz, Mexico. Drug susceptibility testing of 25 clinical isolates revealed that five were susceptible while 20 (80 percent) were DR (15 percent of the annual prevalence for Veracruz). Of the DR isolates, 15 (75 percent) were resistant to rifampin, 17 (85 percent) to isoniazid and 15 (75 percent) were resistant to both drugs (MDR). Sequencing analysis performed in the isolates showed that 14 (93 percent) had mutations in the rpoB gene; seven of these (47 percent) exhibited a mutation at 531 (S[L). Ten (58 percent) of the 20 resistant isolates showed mutations in katG; nine (52 percent) of these 10 exhibited a mutation at 315 (S[T). In conclusion, the DR profile of the isolates suggests a significant number of different DR-TB strains with a low frequency of mutation at codons 531 and 315 in rpoB and katG, respectively. This result leads us to consider different regions of the same genes, as well as other genes for further analysis, which is important if a genetic-based diagnosis of DR-TB is to be developed for this region.

[Immune response during laparoscopic and open living donor nephrectomy. An experimental pig model]. / Respuesta inmunohumoral durante la nefrectomía abierta y laparoscópica de donante vivo. Modelo porcino experimental.

INTRODUCTION: It's been demonstrated laparoscopic access determines a lower surgical stress, by measurement of several markers as different interleuquines (IL) or C-reactive protein (CRP). Endothelin 1 (ET-1) is a powerful vasoconstrictor produced in renal endothelium scarcely studied in laparoscopy. The objective of this study is to analyze immune response during laparoscopic and open donor nephrectomy, in a porcine experimental model by means of measuring IL-2, 10, tumoral necrosis factor alpha (TNFalpha), CRP and ET-1. METHODS: Twenty pigs underwent left nephrectomy, 10 by laparoscopy and 10 by open approach in an experimental model. Both groups were monitorized IL-2, 10, TNF alpha, ET-1 at basal, immediately post surgery, first, third, fifth and seventh days after procedure. RESULTS: The comparative analysis between groups demonstrated a significant increase in levels of CRP (1.44+/-0.88 vs 1.32+/-0.14 mg/dl, p=0.046), TNF alpha (131.14+/-41.37 vs 57.19+/-23.71 pg/ml, p>0.001) and ET-1 (0.91+/-0.49 vs 0.56+/-0.5 fmol/ml, p=0.001) of open nephrectomy group, as a higher levels of IL-2 in laparoscopic group. CONCLUSIONS: Open donor nephrectomy determines a higher immune response than laparoscopic approach. The importance of this fact over the ischemia-reperfusion syndrome or the immediate function of graft is not clearly established.

Persistent transactivation of EGFR and ErbB2/HER2 by protease-activated receptor-1 promotes breast carcinoma cell invasion.

Hyperactivation of ErbB signaling is implicated in metastatic breast cancer. However, the mechanisms that cause dysregulated ErbB signaling and promote breast carcinoma cell invasion remain poorly understood. One pathway leading to ErbB activation that remains unexplored in breast carcinoma cell invasion involves transactivation by G-protein-coupled receptors (GPCRs). Protease-activated receptor-1 (PAR1), a GPCR activated by extracellular proteases, is overexpressed in invasive breast cancer. PAR1 is also proposed to function in breast cancer invasion and metastasis, but how PAR1 contributes to these processes is not known. In this study, we report that proteolytic activation of PAR1 by thrombin induces persistent transactivation of EGFR and ErbB2/HER2 in invasive breast carcinoma, but not in normal mammary epithelial cells. PAR1-stimulated EGFR and ErbB2 transactivation leads to prolonged extracellular signal-regulated kinase-1 and -2 signaling and promotes breast carcinoma cell invasion. We also show that PAR1 signaling through Galpha(i/o) and metalloprotease activity is critical for ErbB transactivation and cellular invasion. Finally, we demonstrate that PAR1 expression in invasive breast carcinoma is essential for tumor growth in vivo assessed by mammary fat pad xenografts. These studies reveal a critical role for PAR1, a receptor activated by tumor-generated proteases, in hyperactivation of ErbB signaling that promotes breast carcinoma cell invasion.

[Experimental models for research and training in renal transplant]. / Modelos experimentales para la investigación y el entrenamiento en trasplante renal.

An update on aspects and use of different experimental models applied in kidney transplant research is presented . This paper includes qualities, as long as similarities between most frequently used animal models and human clinical standards. Contributions of those models based on microsurgical or laparoscopic techniques are revised. The physiological consequences (hemodynamic, immunologic) of surgical technique (laparoscopy), applied in experimental models as long as non-heart beating organ donor models and organ preservation methods are also reviewed. Finally, an update of those models applied in research in prothocols of either immunosupression or xenotransplant is done.

Respuesta inmunohumoral durante la nefrectomía abierta y laparoscópica de donante vivo. Modelo porcino experimental / Immune response during laparoscopic and open living donor nephrectomy. An experimental pig model

Introducción: Se ha demostrado la menor agresividad quirúrgica provocada por el abordaje laparoscópico, en base a la medición de diversos marcadores de estrés postquirúrgico, entre los que se encuentran distintas interleuquinas (IL) y la proteína C reactiva (PCR). La endotelina 1 (ET-1) es un vasoconstrictor potente producido en el endotelio renal escasamente analizado en el curso de la cirugía laparoscópica. El objetivo del trabajo es analizar comparativamente la respuesta inmunohumoral inducida por las nefrectomías laparoscópica y abierta en un modelo experimental porcino, en base a la cuantificación de la PCR, las IL-2, 10, el factor de necrosis tumoral alfa (TNF alfa), y la ET-1.Material y métodos: Se analizan comparativamente dos grupos de cerdos de 25-40 Kg, un grupo CONTROL (N=10) y grupo LAPAROSCÓPICO (N=10), a los que se les realiza una nefrectomía abierta o laparoscópica respectivamente. Se determinó en sangre venosa periférica los niveles de PCR, IL-2, IL-10, TNF α y ET-1. Las determinaciones analíticas se realizaron en los momentos: basal, postcirugía, 1, 3, 5, y 7 días postquirúrgico. Resultados: El análisis comparativo de ambos grupos demuestra un aumento estadísticamente significativo de la PCR(1,44+ 0,88 vs 1,32 + 0,14 mg/dl, p=0,046), TNF α (131,14 + 41,37 vs 57,19 + 23,71 pg/ml, p>0,001) y ET-1 (0,91 + 0,49vs 0,56 + 0,5 fmol/ml, p=0,001) del grupo abierto en comparación con el grupo control, así como una elevación de la IL-2 en el grupo laparoscópico. Conclusiones: La respuesta inmunohumoral inducida por la nefrectomía abierta es superior a la de la nefrectomía laparoscópica en el curso de la donación. La importancia de este hecho en el síndrome isquemia reperfusión o la función inmediata del injerto no está claramente establecida (AU)

Introduction: It’s been demonstrated laparoscopic access determines a lower surgical stress, by measurement of several markers as different interleuquines (IL) or C- reactive protein (CRP). Endothelin 1 (ET-1) is a powerful vasoconstrictor produced in renal endothelium scarcely studied in laparoscopy. The objective of this study is to analyze immune response during laparoscopic and open donor nephrectomy, in a porcine experimental model by means of measuring IL-2,10, tumoral necrosis factor α (TNFα), CRP and ET-1.Methods: Twenty pigs underwent left nephrectomy, 10 by laparoscopy and 10 by open approach in an experimental model. Both groups were monitorized IL-2, 10, TNF α, ET-1 at basal, immediately post surgery, first, third, fifth and seventh days after procedure. Results: The comparative analysis between groups demonstrated a significant increase in levels of CRP (1,44 + 0,88vs 1,32 + 0,14 mg/dl, p=0,046), TNF α (131,14 + 41,37 vs 57,19 + 23,71 pg/ml, p>0,001) and ET-1 (0,91 + 0,49 vs 0,56+ 0,5 fmol/ml, p=0,001) of open nephrectomy group, as a higher levels of IL-2 in laparoscopic group. Conclusions: Open donor nephrectomy determines a higher immune response than laparoscopic approach. The importance of this fact over the ischemia-reperfusion syndrome or the immediate function of graft is not clearly established (AU)

Modelos experimentales para la investigación y el entrenamiento en trasplante renal / Experimental models for research and training in renal transplant

Introducción y objetivos: Se presenta una revisión sobre las diferentes características y el uso de los distintos modelos experimentales utilizados para el trasplante renal (TR). Esta revisión incluye las cualidades, así como sus semejanzas a los humanos, de las especies más frecuentemente utilizadas. Se revisan las aportaciones de los diferentes modelos al entrenamiento de las diferentes técnicas quirúrgicas como la laparoscopia o la microcirugía. Se repasan sus contribuciones al estudio y la investigación en campos como los efectos hemodinámicos o inmunológicos del neumoperitoneo, las técnicas de donante a corazón parado o las diferentes formas de preservación de los injertos. Por último, se realiza una revisión de los diferentes modelos utilizados para la investigación de los distintos protocolos de inmunosupresión así como el xenotrasplante

Introduction and objetives: An update on aspects and use of different experimental models applied in kidney transplant research is presented . This paper includes qualities, as long as similarities between most frequently used animal models and human clinical standards. Contributions of those models based on microsurgical or laparoscopic techniques are revised. The physiological consequences (hemodynamic, immunologic) of surgical technique (laparoscopy), applied in experimental models as long as non-heart beating organ donor models and organ preservation methods are also reviewed. Finally, an update of those models applied in research in prothocols of either immunosupression or xenotransplant is done

Immunohumoral response during laparoscopic and open living donor nephrectomy: an experimental model.

Measurement of interleukins (IL) and C-reactive protein (CRP) have demonstrated that a laparoscopic approach may induce less surgical stress than an open approach. The potential influence of this observation in living donor nephrectomy has scarcely been analyzed. The aim of the study was to analyze the immunohumoral response induced by laparoscopic versus open donor nephrectomy in an experimental model. Twenty pigs underwent left nephrectomy, 10 by laparoscopy and 10 by an open approach. In both groups the following parameters were measured: CRP, IL-2, IL-10, tumour necrosis factor alpha (TNF alpha), and endothelin-1 (ET-1). The determinations were done at different times: basal, immediately as well as on the first, third, fifth, and seventh days after the procedure. A comparative analysis between groups demonstrated a significant increases among the open group in the following markers: CRP (1.44 +/- 0.88 vs 1.32 +/- 0.14 mg/dL, P = .046); TNF alpha (131.14 +/- 41.37 vs 57.19 +/- 23.71 pg/mL; P > .001); and ET-1 (0.91 +/- 0.49 vs 0.56 +/- 0.5 fmol/mL; P = .001). The laparoscopic group showed higher levels of IL-2 than the open group. In conclusion, open donor nephrectomy produced a greater immunohumoral response than a laparoscopic approach. The influence of these observations on ischemia-reperfusion injury or on immediate graft function after kidney transplantation has not been clearly established.

Comparative analysis of the hemodynamic and respiratory parameters during laparoscopic versus open living donor nephrectomy: an experimental model.

Increased intrabdominal pressure induced by pneumoperitoneum induces modifications in cardiovascular and respiratory systems. The aim of the study was to analyze the hemodynamic and respiratory modifications produced by pneumoperitoneum during living donor nephrectomy in a porcine experimental model. Twenty pigs underwent left nephrectomy, 10 by laparoscopy and 10 by an open approach. The following parameters were measured: mean arterial pressure (MAP), central venous pressure, cardiac output (CO), systemic vascular resistance (SVR), end tidal CO2 (ETCO2), minute volume (MV), respiratory airway pressure (RAP), and "compliance." Both groups were monitored for cardiac and respiratory systems at basal, 5, 30, and 60 minutes as well as postsurgery. The comparative analysis demonstrated increased CO with a higher difference at 30 minutes (4.33 +/- 0.73 vs 8.54 +/- 1.26 L/min, P < .001); decreased SVR (1118.81 +/- 302.52 vs 663.37 +/- 81.45 dinas x s x cm(-5), P < .001), and elevated MAP among the laparoscopic group (66.5 +/- 11.52 vs 80.25 +/- 2.49 mm Hg, P = .004). Analysis of respiratory modifications showed an initial increase in ETCO2 (44.3 +/- 2.6 vs 54.1 +/- 12.56 mm Hg, P < .035) and a higher MV administered (5.6 +/- 0.1 vs 7.01 +/- 0.96 L/min, P = .03) to the laparoscopy group. An increased RAP was observed at 5 minutes (22.11 +/- 2.76 vs 28.8 +/- 3.68 mm Hg, P < .001), in the laparoscopic group and lower levels of "compliance" at the same moment in that group (16 +/- 1.66 vs 14.9 +/- 4.07 cm H2O). Laparoscopic nephrectomy caused an increase in CO and MAP and decreased SVR. Likewise there were elevations of RAP, ETCO2, and MV and a slight decrease in the "compliance."

Role of mitogen-activated protein kinase kinase kinases in signal integration.

Mitogen-activated protein kinases (MAPKs) are members of a dynamic protein kinase network through which diverse stimuli regulate the spatio-temporal activities of complex biological systems. MAPKs regulate critical cellular functions required for homeostasis such as the expression of cytokines and proteases, cell cycle progression, cell adherence, motility and metabolism. MAPKs therefore influence cell proliferation, differentiation, survival, apoptosis and development. In vertebrates, five MAPK families are regulated by MAPK kinase kinase-MAPK kinase-MAPK (MKKK-MKK-MAPK) phosphorelay systems. There are at least 20 MKKKs that selectively phosphorylate and activate different combinations of the seven MKKs, resulting in a specific activation profile of members within the five MAPK families. MKKKs are differentially activated by upstream stimuli including cytokines, antigens, toxins and stress insults providing a mechanism to integrate the activation of different MAPKs with the cellular response to each stimulus. Thus, MKKKs can be considered as 'signaling hubs' that regulate the specificity of MAPK activation. In this review, we describe how the MKKK 'hub' function regulates the specificity of MAPK activation, highlighting MKKKs as targets for therapeutic intervention in cancer and other diseases.

Lack of subclinical myocardial ischaemia in Mexican patients with systemic lupus erythematosus without traditional risk factors for coronary artery disease.

The objective of this study was to analyse whether patients with systemic lupus erythematosus (SLE) without traditional risk factors for coronary artery disease (CAD) develop subclinical myocardial ischaemia in the first years after diagnosis. A cross-sectional analysis of a cohort of 200 female SLE patients was conducted. We selected those patients who fulfilled the American College of Rheumatology (ACR) SLE criteria and had no traditional risk factors for CAD, including diabetes mellitus, hypertension, obesity, hyperlipidemia, and smoking. After an initial clinical and laboratory examination, patients were evaluated using a baseline echocardiogram and a dobutamine and atropine stress echocardiogram to search for subclinical myocardial ischaemia. Forty-one patients were included in the study. The mean age at the time of the study was 34.5 +/- 9.56 years (mean +/- SD). The mean age at diagnosis was 30.3 +/- 9.39 years. The mean time from diagnosis was 3.9 +/- 3.3 years. Baseline disease activity index (MEX-SLEDAI score) showed that 92.6% of patients had disease activity, although most patients had mild activity. A dobutamine and atropine stress echocardiogram was performed in 40 patients. All 40 patients had negative tests for subclinical myocardial ischaemia. Patients without traditional risk factors for CAD do not have an increased risk for subclinical myocardial ischaemia in the first years after diagnosis. A longitudinal follow-up study of these patients is needed to confirm our findings and assess if additional non-traditional risk factors for CAD increase the risk for myocardial ischaemia.

Re-activation of a dormant tumor suppressor gene maspin by designed transcription factors.

The controlled and specific re-activation of endogenous tumor suppressors in cancer cells represents an important therapeutic strategy to block tumor growth and subsequent progression. Other than ectopic delivery of tumor suppressor-encoded cDNA, there are no therapeutic tools able to specifically re-activate tumor suppressor genes that are silenced in tumor cells. Herein, we describe a novel approach to specifically regulate dormant tumor suppressors in aggressive cancer cells. We have targeted the Mammary Serine Protease Inhibitor (maspin) (SERPINB5) tumor suppressor, which is silenced by transcriptional and aberrant promoter methylation in aggressive epithelial tumors. Maspin is a multifaceted protein, regulating tumor cell homeostasis through inhibition of cell growth, motility and invasion. We have constructed artificial transcription factors (ATFs) made of six zinc-finger (ZF) domains targeted against 18-base pair (bp) unique sequences in the maspin promoter. The ZFs were linked to the activator domain VP64 and delivered in breast tumor cells. We found that the designed ATFs specifically interact with their cognate targets in vitro with high affinity and selectivity. One ATF was able to re-activate maspin in cell lines that comprise a maspin promoter silenced by epigenetic mechanisms. Consistently, we found that this ATF was a powerful inducer of apoptosis and was able to knock down tumor cell invasion in vitro. Moreover, this ATF was able to suppress MDA-MB-231 growth in a xenograft breast cancer model in nude mice. Our work suggests that ATFs could be used in cancer therapeutics as novel molecular switches to re-activate dormant tumor suppressors.

Pancreas islet transplantation in the genitourinary tract associated with renal transplantation: an experimental study.

Conceptually, pancreas islet transplantation (PIT) associated with renal transplantation (RT) should resolve not only chronic renal failure but also diabetes. Although the most frequently used site for PIT is the portal vein, genitourinary locations could be technically feasible during RT. Seventeen pigs (age 3 to 4 months; mean weight 34.5 kg) underwent the following experimental steps: On day 1 a left nephrectomy was performed and the kidney was perfused with cold Wisconsin solution. This was followed by a caudal pancreatectomy and islet isolation by means of digestion with intraductal collagenase. Islets were stained with Dithizone and cultured overnight al 37 degrees C and 5% CO(2). On day 2 a right nephrectomy and orthotopic RT of the preserved left kidney were performed. The islets were transplanted into four different sites: subcapsular in the kidney graft, in the bladder submucosa, in the testis by puncture, and in the testis by infusion through the vas deferens. On day 7 the animals were sacrificed. Islet viability was determined by histological examination with insulin immunostaining and determination of insulin in the blood of the veins draining the implantation sites. The mean weight of the pancreatic specimens was 27.8 g (13 to 46). The mean number of islets was 536,000 (16,600 to 1,5000,000). Islets were shown in the bladder submucosa and the testes after vas deferens infusion. The number of viable islets in the other implantation sites was very scarce. The insulin levels of the venous effluents were: 15.1 microU/mL for bladder submucosa, 10.2 microU/mL for intradeferential injection in the testis, 7.3 microU/mL for intratesticular injection by puncture, and 2.6 microU/mL for subcapsular implantation in the graft. In conclusion, the bladder submucosa and testis via the vas deferens might represent alternative sites for PIT. The latter route may benefit from the immunoprivileged and special trophic conditions of the testis. For the first time, the feasibility of the bladder submucosa as an implantation site for pancreas islets was demonstrated.

MEKK1 controls matrix degradation and tumor cell dissemination during metastasis of polyoma middle-T driven mammary cancer.

Mammary tumor cells are required to degrade the surrounding matrix and disseminate in order to metastasize, and both of these processes are controlled by a tumor cell-signaling network that remains poorly defined. MEKK1 is a MAPKKK that regulates both the extracellular signal regulated kinase (ERK1/2) and the c-Jun amino terminal kinase (JNK) signaling pathways. MEKK1 signaling regulates migration through control of cell adhesion and is required for inducible expression of urokinase-type plasminogen activator (uPA). MEKK1-deficient mice with mammary gland-targeted expression of the polyoma middle T antigen (PyMT) transgene develop primary mammary tumors at a rate and frequency similar to wild-type littermates, indicating that MEKK1 deficiency does not affect PyMT-mediated transformation. However, MEKK1-/- mice display significantly delayed tumor cell dissemination and lung metastasis. Delayed MEKK1-dependent tumor dissemination is associated with markedly reduced tumor uPA expression, gelatinase activity, and prolonged tumor basement membrane integrity. siRNA-mediated MEKK1 knockdown inhibits uPA activity, cell migration and invasion in MDA-MB-231 human breast cancer cells. Thus MEKK1 controls tumor progression by regulating both the migration and proteolysis aspects of tumor cell invasiveness. To our knowledge, this is the first example of a MAPKKK that regulates metastasis through control of tumor invasiveness.

Angiogenic capacity of human omental stem cells.

OBJECTIVES: The goals of the present study are to obtain, expand and characterize a stem cell population from human omentum and to evaluate its in vivo angiogenic capacities. METHODS: Human omental CD34+ cells were obtained from samples of human omentum by density gradient centrifugation in Ficoll. Proliferative pattern, marker expression (by flow cytometry) and angiogenic growth factor synthesis by omental cell cultures were determined. In vivo angiogenic capacity of the cells was evaluated in rats. RESULTS: Omental stem cells showed a high rate of proliferation (Ki67 staining), expressed CD34 marker and synthesized bFGF and VEGF. When implanted in rats, omental cells promoted neovascularization. Human omental cells were localized in rat tissue, mainly forming the endothelium of neo-vessels. Implantation of omental cells also facilitated angiogenesis of rat origin. CONCLUSION: CD34+ cell population of human omentum could be responsible for the clinical benefit of omental transplantation by promoting angiogenesis and synthesizing angiogenic growth factors to facilitate revascularization of injured tissue.