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Transcription termination in eukaryotic cells involves the recognition of polyadenylation signals (PAS) that signal the site of pre-mRNA cleavage and polyadenylation. Most eukaryotic genes contain multiple PAS that are used by alternative polyadenylation (APA), a co-transcriptional process that increases transcriptomic diversity and modulates the fate of the mRNA and protein produced. However, current tools to pinpoint the relationship between mRNAs in different subcellular fractions and the gene expression outcome are lacking, particularly in primary human immune cells, which, due to their nature, are challenging to study. Here, we describe an integrative approach using subcellular fractionation and RNA isolation, chromatin-bound and nucleoplasmic RNA-Sequencing, 3' RNA-Sequencing and bioinformatics, to identify accurate APA mRNA isoforms and to quantify gene expression in primary human macrophages. Our protocol includes macrophage differentiation and polarization, co-culture with cancer cells, and gene silencing by siRNA. This method allows the simultaneous identification of macrophage APA mRNA isoforms integrated with the characterization of nuclear APA events, the identification of the molecular mechanisms involved, as well as the gene expression alterations caused by the cancer-macrophage crosstalk. With this methodology we identified macrophage APA mRNA signatures driven by the cancer cells that alter the macrophage inflammatory and transcriptomic profiles, with consequences for macrophage physiology and tumor evasion.

Transcription termination in eukaryotic cells involves the recognition of polyadenylation signals (PAS) that signal the site of pre-mRNA cleavage and polyadenylation. Most eukaryotic genes contain multiple PAS that are used by alternative polyadenylation (APA), a co-transcriptional process that increases transcriptomic diversity and modulates the fate of the mRNA and protein produced. However, current tools to pinpoint the relationship between mRNAs in different subcellular fractions and the gene expression outcome are lacking, particularly in primary human immune cells, which, due to their nature, are challenging to study. Here, we describe an integrative approach using subcellular fractionation and RNA isolation, chromatin-bound and nucleoplasmic RNA-Sequencing, 3′ RNA-Sequencing and bioinformatics, to identify accurate APA mRNA isoforms and to quantify gene expression in primary human macrophages. Our protocol includes macrophage differentiation and polarization, co-culture with cancer cells, and gene silencing by siRNA. This method allows the simultaneous identification of macrophage APA mRNA isoforms integrated with the characterization of nuclear APA events, the identification of the molecular mechanisms involved, as well as the gene expression alterations caused by the cancer-macrophage crosstalk. With this methodology we identified macrophage APA mRNA signatures driven by the cancer cells that alter the macrophage inflammatory and transcriptomic profiles, with consequences for macrophage physiology and tumor evasion.

Background An automated method for 3D reconstruction of coronary sinus (CS) lead’s pacing cathode trajectory (3DTJ) was proposed to acutely predict long term left ventricular (LV) mechanic response to cardiac resynchronization therapy (CRT). Preliminary data showed that 3DTJ at biventricular pacing (BIV) start changed in CRT responders (R) to be, becoming less eccentric and more multi-directional, as described by the ratio between its two major axes (S1/S2). Purpose The TRAJECTORIES study (Trajectory Changes Of Coronary Sinus Lead Tip And Cardiac Resynchronization Therapy Outcome, NCT02340546) is an observational study by seven Italian centers about the prediction of CRT-induced LV reverse remodeling by means of the acute 3DTJ changes at CRT implant. Methods In CRT implants with standard indications, stable CHF and regular ventricular rhythm, a fluoroscopic sequence in two standard X-rays views of a few seconds was acquired immediately before (T-1) and after the start of BIV (T0). 3DTJ of CS lead cathode pole throughout the cardiac cycle at T-1 and T0 were reconstructed and analyzed. Changes of the ratio between its two major axes (S1/S2) between T-1 and T0 (ΔS1/S2), were compared with the volumetric response at six-month f.u: the percent negative variation of S1/S2 (ΔS1/S2 Results Out of 119 patients enrolled in 42 months, 74 pts ended f.u. (55 m; age 69 ± 10) and 30 dropped–out. Patients baseline features were: ischemic heart disease (IHD) 34 /74 pts; sinus rhythm 64/74 pts; upgrade from PM/ICD 13/74 pts; QRS morphology with LBBB 57/74, intraventricular aspecific delay 6 and RV pace 11 pts; LV ejection fraction (EF) 30 ± 9%; QRS duration 162 ± 25 ms. At f.u., volumetric R were 45/74 (60%). Concordance between ΔS1/S2 (as either ΔS1/S2 0) and volumetric response was 77% overall (57/74), 82% in R (37/45), 69% in non-R (20/29). Non-concordant patients were mostly non-R: 52% vs 35% of non-R in concordant group, but no other differences were found. The proposed 3DTJ metric showed sensitivity = 72%, specificity =80%; positive predictive value = 69%, negative predictive value = 82%. Conclusions Metrics of 3DTJ can be useful to acutely predict CS pacing site-specific response to CRT in long-term, above all in R. 3DTJ assessment might highlight aspects of CRT effects on LV mechanics.

Glioblastoma (GBM) is the most frequent and aggressive type of brain tumor. There are limited therapeutic options for GBM so that new and effective agents are urgently needed. Euphol is a tetracyclic triterpene alcohol, and it is the main constituent of the sap of the medicinal plant Euphorbia tirucalli. We previously identified anti-cancer activity in euphol based on the cytotoxicity screening of 73 human cancer cells. We now expand the toxicological screening of the inhibitory effect and bioactivity of euphol using two additional glioma primary cultures. Euphol exposure showed similar cytotoxicity against primary glioma cultures compared to commercial glioma cells. Euphol has concentration-dependent cytotoxic effects on cancer cell lines, with more than a five-fold difference in the IC50 values in some cell lines. Euphol treatment had a higher selective cytotoxicity index (0.64-3.36) than temozolomide (0.11-1.13) and reduced both proliferation and cell motility. However, no effect was found on cell cycle distribution, invasion and colony formation. Importantly, the expression of the autophagy-associated protein LC3-II and acidic vesicular organelle formation were markedly increased, with Bafilomycin A1 potentiating cytotoxicity. Finally, euphol also exhibited antitumoral and antiangiogenic activity in vivo, using the chicken chorioallantoic membrane assay, with synergistic temozolomide interactions in most cell lines. In conclusion, euphol exerted in vitro and in vivo cytotoxicity against glioma cells, through several cancer pathways, including the activation of autophagy-associated cell death. These findings provide experimental support for further development of euphol as a novel therapeutic agent for GBM, either alone or in combination chemotherapy., The work was supported by the Amazonia Fitomedicamentos (FITO05/2012) Ltda. and Barretos Cancer Hospital, all from Brazil.

In colon cancer, the prognostic value of macrophages is controversial, and it is still unknown how hypoxia modulates macrophage&ndash, cancer cell crosstalk. To unravel this, co-cultures of human primary macrophages and colon cancer cells were performed at 20% and 1% O2, followed by characterization of both cellular components. Different colon cancer patient cohorts were analyzed for hypoxia and immune markers, and their association with patient overall survival was established. A positive correlation between HIF1A and CD68 in colon cancer patients was identified but, unexpectedly, in cases with higher macrophage infiltration, HIF1A expression was associated with a better prognosis, in contrast to breast, gastric, and lung cancers. Under hypoxia, co-cultures&rsquo, secretome indicated a shift towards a pro-inflammatory phenotype. These alterations occurred along with increased macrophage phagocytic activity and decreased SIRP&alpha, expression. Cancer cells were more invasive and exhibited higher CD47 expression. We hypothesize that the better prognosis associated with HIF1AHighCD68High tumors could occur due to macrophagic pro-inflammatory pressure. Indeed, we found that tumors HIF1AHighCD68High expressed increased levels of CD8A, which is positively correlated with HIF1A. In conclusion, we show that in colon cancer, hypoxia drives macrophages into a pro-inflammatory phenotype, concomitant with increased infiltration of anti-tumor immune cells, favoring better disease outcome.

International audience; Multispecies biofilms represent the dominant mode of life for the vast majority of microorganisms. Bacterial spatial localization in such biostructures governs ecological interactions between different populations and triggers the overall community functions. Here, we discuss the pros and cons of fluorescence-based techniques used to decipher bacterial species patterns in biofilms at single cell level, including fluorescence in situ hybridization and the use of genetically modified bacteria that express fluorescent proteins, reporting the significant improvements of those techniques. The development of tools for spatial and temporal study of multispecies biofilms will allow live imaging and spatial localization of cells in naturally occurring biofilms coupled with metabolic information, increasing insight of microbial community and the relation between its structure and functions.

Inflammation, oxidative and nitrosative stress underlie depression being assessed in rodents by the systemic administration of lipopolysacharide (LPS). There is an increasing body of evidence of an involvement of nitric oxide (NO) pathway in depression, but this issue was not investigated in LPS-induced model. Thus, herein we evaluated the effects of NO-pathway-modulating drugs, named aminoguanidine, l-NAME, sildenafil and l-arginine, on the behavioral (forced swimming test [FST], sucrose preference [SPT] and prepulse inhibition [PPI] of the startle) and neurochemical (glutathione [GSH], lipid peroxidation, IL-1β) alterations in the prefrontal cortex, hippocampus and striatum as well as in BDNF levels in the hippocampus 24h after LPS (0.5mg/kg, i.p.) administration, a time-point related to depressive-like behavior. Twenty-four hours post LPS there was an increase in immobility time in the FST, decrease in sucrose preference and PPI levels accompanied by a decrease in GSH levels and an increase in lipid peroxidation, IL-1β and hippocampal BDNF levels suggestive of a depressive-like state. The pretreatment with the NOS inhibitors, l-NAME and aminoguanidine as well as sildenafil prevented the behavioral and neurochemical alterations induced by LPS, although sildenafil and l-NAME were not able to prevent the increase in hippocampal BDNF levels induced by LPS. The iNOS inhibitor, aminoguanidine, and imipramine prevented all behavioral and neurochemical alterations induced by LPS. l-arginine did not prevent the alterations in immobility time, sucrose preference and GSH induced by LPS. Taken together our results show that the NO-cGMP pathway is important in the modulation of the depressive-like alterations induced by LPS.

PURPOSE BRAF(V600E) mutation represents the most common oncogenic event in sporadic papillary thyroid cancer (PTC). There are, however, significant discrepancies regarding the overall frequency, its prevalence in PTC-variants, and its relationship with clinico-pathological parameters of poor outcome. Moreover, the impact of BRAF(V600E) mutants on tumour-related patient's death has not been evaluated. DESIGN We analysed, by PCR-SSCP and/or PCR-direct sequencing, exons 8, 10, 11 and 15 of BRAF in 113 tumour samples from 49 PTC-patients. Matched lymph node metastases and/or distant metastases (DMs) were screened in 35 patients. Focal changes in the growth pattern or microscopic grade within the primary tumour (Pt) or the metastases were separately genotyped. Mutations at H-, K-, N-ras and PIK3CA exons 9 and 20 were also investigated. For comparison with PTC cases, the BRAF and Ras mutational status was evaluated in 89 specimens obtained from 24 poorly differentiated thyroid carcinomas (PDCs) and 36 anaplastic thyroid carcinomas (ATCs). RESULTS BRAF(V600E) was found in 13/16 classical PTCs (CL-PTCs), 6/17 follicular variant PTCs (FV-PTCs) and 8/16 mixed (papillary/follicular) PTCs (Mx-PTCs), being significantly associated with CL-PTCs (P = 0.015). BRAF(V600E) segregated with metastatic PTC-cells in 43% of the patients, but only one DM disclosed the mutation. PTC-tumours featuring concurrent less-differentiated foci were BRAF wild-type in both components. Noteworthy, the frequency of BRAF mutations among PDCs and ATCs resulted considerably lower (16.6% and 25%, respectively) than in PTCs (55%). The prevalence of Ras mutations among PDCs and ATCs (46% and 36%, respectively) was, however, much higher than in PTCs (14%). Five (71%) of the patients who died of PTC displayed somatic mutations. Four of them had other gene alteration associated with BRAF(V600E) and the only one that did not, BRAF(V600E) was restricted to the Pt. The occurrence of BRAF(V600E) associated with other genetic events was an independent predictor of DMs during follow-up, recurrence and tumour-related death. Remarkably, two PDCs (8.3%) and five ATCs (14%) revealed concurrent BRAF and Ras mutations. CONCLUSION BRAF(V600E)'alone' does not represent a marker for poor outcome, however, when associated with alterations in other genes identifies a subset of PTCs with increased risk of recurrence and decreased survival.

International audience; Helicobacter pylori colonizes the human stomach and increases the risk for peptic ulcer disease and gastric carcinoma. H. pylori upregulates the expression and activity of several matrix metalloproteinases (MMPs) in cell lines and in the gastric mucosa. The aim of this study was to explore the mechanisms leading to upregulation of MMP10 in gastric epithelial cells induced by H. pylori. Infection of gastric cells with H. pylori led to an increase in levels of MMP-10 messenger RNA, protein secretion, and activity. cagA knockout mutants or CagA phosphorylation-defective mutants failed to increase MMP10 expression. These results were confirmed in infection experiments with clinical isolates with known cagA status and in human gastric biopsy specimens. Treatment of cells with chemical inhibitors of the receptor tyrosine kinase EGFR and the kinase Src abrogated H. pylori-induced MMP10 expression. Inhibitors of ERK1/2 and JNK kinases abolished and significantly decreased H. pylori-induced MMP10 expression, respectively, whereas inhibition of the kinase p38 had no effect. Finally, inhibition of MMP10 expression by small interfering RNA led to a decrease in the gastric cell-invasive phenotype mediated by the infection. In conclusion, CagA-positive H. pylori strains stimulate MMP10 expression. MMP-10 modulation occurs via EGFR activation in a process that involves Src, ERK, and JNK pathways. MMP-10 may be implicated in H. pylori-mediated extracellular matrix remodeling.

The phosphatidylinositol 3′-kinase (PI3K) pathway is frequently activated in thyroid carcinomas through the constitutive activation of stimulatory molecules (e.g., Ras) and/or the loss of expression and/or function of the inhibitory PTEN protein that results in Akt activation. Recently, it has been reported that somatic mutations within the PI3K catalytic subunit, PIK3CA, are common (25-40%) among colorectal, gastric, breast, ovarian cancers, and high-grade brain tumors. Moreover, PIK3CA mutations have a tendency to cluster within the helical (exon 9) and the kinase (exon 20) domains. In this study, 13 thyroid cancer cell lines, 80 well-differentiated thyroid carcinomas of follicular (WDFC) and papillary (WDPC) type, and 70 anaplastic thyroid carcinomas (ATC) were investigated, by PCR-direct sequencing, for activating PIK3CA mutations at exons 9 and 20. Nonsynonymous somatic mutations were found in 16 ATC (23%), two WDFC (8%), and one WDPC (2%). In 18 of the 20 ATC cases showing coexisting differentiated carcinoma, mutations, when present, were restricted to the ATC component and located primarily within the kinase domain. Three cell lines of papillary and follicular lineage (K1, K2, and K5) were also found mutated. In addition, activation of Akt was observed in most of the ATC harboring PIK3CA mutations. These findings indicate that mutant PIK3CA is likely to function as an oncogene among ATC and less frequently well-differentiated thyroid carcinomas. The data also argue for a role of PIK3CA targeting in the treatment of ATC patients.

Activating BRAF mutations are frequent in thyroid follicular cell carcinogenesis. The BRAFV600E point mutation represents the most common oncogenic event in sporadic papillary thyroid cancer (PTC). Although at a much lower frequency the BRAFV600E mutation is also present among less differentiated, more aggressive, I131 resistant forms of thyroid cancer as poorly differentiated carcinomas (PDCs) and undifferentiated carcinomas (UCs). Small molecule inhibitors targeting either the BRAF V600E protein or upstream or downstream kinases involved in MAPK signalling are currently under pre-clinical or clinical investigation in advanced, metastatic, I131 resistant thyroid cancers. Recently, immunohistochemical (IHC) studies on PTCs, using the VE1 mouse anti-human BRAF V600E antibody have shown to be a reliable means for detecting the BRAFV600E mutation in a clinical setting without molecular genotyping units. In this study we sought to determine the usefulness of the VE1 antibody for detecting the BRAF V600E mutant protein in a series of 103 aggressive thyroid cancers (59 PDCs and 44 UCs) previously characterized by PCR-SSCP for the presence of BRAF mutations in exons 11 and 15. The BRAFV600E mutation was present in 10/59 PDCs (17%) and 11/44 UCs (25%). Immunohistochemistry revealed 9 mutated PDCs (sensitivity 90%) and 9 mutated UCs (82% sensitivity). The staining intensity in BRAF V600E mutated samples ranged from weak to strong. Non valuable results were found in 3 PDCs and 4 UCs. Overall the results indicate that immunohistochemistry with VE1 antibody may be an alternative to molecular biology approaches for the routine detection of BRAFV600E point mutations in clinical settings without molecular genotyping facilities. It may help clinicians in targeted therapy decision making. Citation Format: Noa Feás-Rodríguez, Angela M. Costa, Tomás Alvarez Gago, Juan José Mateos Otero, Jose Manuel Cameselle Teijeiro, Raquel Muñoz, Ginesa Maria Garcia-Rostan. Usefulness of VE1 immunohistochemical detection of BRAFV600E in aggressive thyroid cancers (PDCs and UCs). [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 4222.

E-cadherin and P-cadherin are major contributors to cell-cell adhesion in epithelial tissues, playing pivotal roles in important morphogenetic and differentiation processes during development, and in maintaining integrity and homeostasis in adult tissues. It is now generally accepted that alterations in these two molecules are observed during tumour progression of most carcinomas. Genetic or epigenetic alterations in E- and P-cadherin-encoding genes (CDH1 and CDH3, respectively), or alterations in their proteins expression, often result in tissue disorder, cellular de-differentiation, increased invasiveness of tumour cells and ultimately in metastasis. In this review, we will discuss the major properties of E- and P-cadherin molecules, its regulation in normal tissue, and their alterations and role in cancer, with a specific focus on gastric and breast cancer models.

Helicobacter pylori interacts with gastric epithelial cells, activating signaling pathways important for carcinogenesis. In this study we examined the role of H. pylori on cell invasion and the molecular mechanisms underlying this process. The relevance of H. pylori cag pathogenicity island-encoded type IV secretion system (T4SS), CagA, and VacA for cell invasion was also investigated. We found that H. pylori induces AGS cell invasion in collagen type I and in Matrigel invasion assays. H. pylori-induced cell invasion requires the direct contact between bacteria and cancer cells. H. pylori-mediated cell invasion was dependent on the activation of the c-Met receptor and on increased MMP-2 and MMP-9 activity. The abrogation of the c-Met receptor using the specific NK4 inhibitor or the silencing of c-Met expression with small interference RNA suppressed both cell invasion and MMP activity. Studies with different H. pylori strains revealed that cell invasion, c-Met tyrosine phosphorylation, and increased MMP-2 and MMP-9 activity were all dependent on the presence of a functional bacterial T4SS, but not on VacA cytotoxicity. Our findings demonstrate that H. pylori strains with a functional T4SS stimulate gastric epithelial cell invasion through a c-Met-dependent signaling pathway that comprises an increase in MMP-2 and MMP-9 activity.

In the field of biomedical applications a special interest exists regarding the study of the physicochemical and mechanical behaviour of materials, with special focus on the electrochemical degradation of metal/ceramic interfaces. In fact, etal/ceramic interfaces may be present in several biomedical devices, ranging from external or implantable sensors, to dental implants. Diffusion bonding represents an important technique since, in opposition to other production technologies, such as active metal brazing, avoid the possible liberation of certain chemical components harmful to health. The aim of this work is to study the electrochemical degradation of the interface formed between commercially pure Ti and Al2O3 produced by diffusion bonding, in contact with a physiological solution. The present approach included the evaluation of the contribution of individual and pairs of interfacial layers on the global degradation processes. For this propose d.c. electrochemical techniques were used to monitor the open-circuit potential, and to perform potentiodynamic polarization and galvanic corrosion evaluation. Also, electrochemical impedance spectroscopy was used as a complementary technique of the corrosion behaviour of the interface. Chemical composition and morphology of samples and corrosion products were evaluated by SEM and EDS analysis. According to experimental results, two principal reaction layers were formed in the interface: TiAl and Ti3Al. The TiAl layer appears to be the responsible for the strong increase in corrosion rate of the interface., Fundação para a Ciência e Tecnologia -POCTI/CTM/33384/2000; SFRH/BPD/ 5518/2001.

The BRAFV600E mutation represents the most common oncogenic event in sporadic papillary thyroid cancer (PTC). Although at a much lower frequency, different missense point mutations (K601E, G474R, G469R) and complex genetic alterations, such as rearrangements (AKAP9-BRAF) or frameshift mutations (V600EK601del, V599ins, V600D-FLAGT601-605ins, T599I-VKSRdel), have also been reported in PTC. In contrast with PTC, no other alteration different from the V600E substitution has been shown in anaplastic thyroid carcinomas (ATC). In this study, we sought to determine the functional relevance of particular aminoacid residues, within the BRAF kinase domain, that we found mutated in some ATC. Fifty-four ATC were investigated for the existence of mutations at the activation loop, the glicine-rich phosphate-binding loop and the AKT binding sites of BRAF by means of PCR-SSCP and direct sequence. The structural-conformational changes behind punctual, unreported BRAF mutations and their effect on BRAF catalytic activity, substrate binding and downstream MAPK signalling were evaluated. Besides the V600E mutation, two additional point mutations (G615E and G474R) were detected within the BRAF kinase domain. The prevalence of both mutations, G615E (11% = 6 ATC) and G474R (7.4% = 4 ATC), was much lower than that of V600E (20% = 11 ATC). Interestingly, structural biology studies showed that G615E and G474R induced profound conformational changes within the BRAF kinase domain that resulted in reduced catalytic activity, decreased substrate binding and impaired downstream signalling. The G474R mutant, by preventing the N lobe from folding into a well ordered beta sheet structure, caused a broken or distorted phosphorylation-loop (P-loop). Because the P-loop is pivotal for ATP coordination and phosphotransfer reactions, the kinase activity of the BRAF G474R mutant was severely compromised and BRAF was unable to phosphorylate the downstream substrate. The G615E mutant by disrupting the structural integrity of the activation segment in the C lobe could in addition inhibit substrate binding. Significantly, none of the ATC bearing the G615E or the G474R mutation expressed the phospho-p44/42 MAPK (Thr202/Tyr204), which specifically recognizes the dually phosphorylated and active forms of ERK1 and ERK2. This observation not only supported the existence of impaired BRAF kinase activity in vivo but also suggested the abrogation of intracellular MEK/ERK signalling in those tumours. In summary, this study demonstrates that G615E and G474R behave similarly to D594V and the kinase-dead BRAFK483M mutant, knocking-down BRAF catalytic activity and downstream MEK/ERK signalling. Clinical trials involving the inhibitor of threonine/serine kinases Sorafenib or kinase specific inhibitors targeting constitutively active BRAF will prove inefficient therapeutic strategies in patients with G615E or G474R mutations. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 4171. doi:1538-7445.AM2012-4171

The MAPK and the PI3K pathways are viewed as therapeutic targets of the future due to their pivotal role in cellular proliferation, growth regulation, survival, adhesion, motility and spreading. While genetic alterations of effectors along the MAPK pathway are early events in thyroid follicular cell carcinogenesis, being some of them (oncogenic BRAF and RAS activation) also involved in tumour dedifferentiation and progression, the genetic alterations of effectors along the PI3K pathway are normally associated with late stage, advanced thyroid cancers. So far only one study has addressed the prevalence of PIK3CA mutations in poorly differentiated thyroid carcinomas (PDC). Because conventional treatment is clearly ineffective among late stage, advanced thyroid cancers in this study we focused on genotyping “druggable” oncogenes encoding effectors of both pathways. Mutations at BRAF, H-, K-, N-RAS and PIK3CA were investigated by PCR-SSCP-direct sequencing in 40 PDC and 55 anaplastic thyroid carcinomas (ATC). Focal changes in the growth pattern or microscopic grade within the primary tumour, recurrences and metastases were separately genotyped (144 samples). Mutational status was correlated with the expression of downstream effectors such as p-ERK and p-AKT. While the overall prevalence of PIK3CA mutations and BRAF mutations in ATC was almost twice that of PDC [PIK3CA: 29% and 20% respectively; BRAF: 22% and 12.5% respectively], the overall prevalence of RAS mutations in PDC resulted considerably higher than in ATC [45% and 36% respectively]. Concurrent BRAF and RAS mutations were present in 2 PDC (5%) and 5 ATC (9%). Concurrent RAS and PIK3CA mutations were found in 4 PDC (10%) and 4 ATC (7%). Concurrent BRAF and PIK3CA mutations or concurrent BRAF + RAS + PIK3CA mutations were only identified among ATC (2 cases, 4%). Activation of AKT was observed in most PDC and ATC harbouring PIK3CA mutations [86% and 90% respectively]. Phospho-p44/42 MAPK, which specifically recognizes the dually phosphorylated and active forms of ERK1 and ERK2 was present in 50% of the PDC and 55.5% of the ATC bearing the BRAFV600E mutation. PDC and ATC with RAS mutations were found to signal preferentially via PI3K. Among the RAS mutated PDC 69% demonstrated activation of AKT and 31% activation of ERK. Among RAS mutated ATC 85% exhibited AKT activation and 46% ERK activation. Co-activation of both pathways (p-AKT and p-ERK) was seen in 2 PDC (12.5%, both cases RAS +) and 5 ATC [38%; 4 cases RAS + plus 1 case RAS + and BRAF +]. Strikingly, all 4 PDC mutated at RAS and PIK3CA had distant metastases at diagnosis and died of disease. These findings may significantly impact on the rationale of future, tailored gene targeted therapies applied to patients with ATC and PDC. Our results suggest that activation of the PI3K pathway is pivotal in disease dedifferentiation and progression which has important implications in PDC and ATC management. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 3137.

Mucosal epithelia are targeted by several microorganisms as a way of adhesion, internalization, and/or exploitation of the host properties to induce disease. Helicobacter pylori are worldwide prevalent bacteria that colonize the human stomach. Persistent infection of the gastric mucosa with H. pylori and concurrent chronic gastritis are risk factors for ulcer disease and gastric carcinoma. Therefore, interactions at the H. pylori–epithelial interface are important to understand the pathogenesis of these bacteria and the host responses that contribute to disease development. Here, we provide an overview of the interactions between microorganisms and the adherens junctions with an emphasis on H. pylori.

Matrix metalloproteinases (MMPs) are proteolytic enzymes that degrade extracellular matrix (ECM), thus assisting invasion. Upregulation of MMPs, frequently reported in gliomas, is associated with aggressive behavior. WNK2 is a tumor suppressor gene expressed in normal brain, and silenced by promoter methylation in gliomas. Patients without WNK2 exhibited poor prognosis, and its downregulation was associated with increased glioma cell invasion. Here we showed that MMP2 expression and activity are increased in glioma cell lines that do not express WNK2. Also, WNK2 inhibited JNK, a process associated with decreasing levels of MMP2. Thus, WNK2 promoter methylation and silencing in gliomas is associated with increased JNK activation and MMP2 expression and activity, thus explaining in part tumor cell invasion potential., This work was supported by a Portuguese Foundation for Science and Technology (FCT) projects PTDC/SAU-TOX/114549/2009, and PTDC-SAU-ONC/112511/2009. AMC is a Post-doc Fellow (PTDC/SAU-TOX/114549/2009), and FP is a PhD Fellow (SFRH/BD/81369/2011) from FCT. OM is a Post-doc Fellow from QREN (UMINHO/BPD/32/2013). MJO is an Investigator FCT recipient.