PATZ1 acts as a tumor suppressor in thyroid cancer via targeting p53-dependent genes involved in EMT and cell migration

PATZ1, a POZ-Zinc finger protein, is emerging as an important regulator of development and cancer, but its cancer-related function as oncogene or tumor-suppressor is still debated. Here, we investigated its possible role in thyroid carcinogenesis. We demonstrated PATZ1 is down-regulated in thyroid carcinomas compared to normal thyroid tissues, with an inverse correlation to the degree of cell differentiation. In fact, PATZ1 expression was significantly further down-regulated in poorly differentiated and anaplastic thyroid cancers compared to the papillary histotype, and it resulted increasingly delocalized from the nucleus to the cytoplasm proceeding from differentiated to undifferentiated thyroid carcinomas. Restoration of PATZ1 expression in three thyroid cancer-derived cell lines, all characterized by fully dedifferentiated cells, significantly inhibited their malignant behaviors, including in vitro proliferation, anchorage-independent growth, migration and invasion, as well as in vivo tumor growth. Consistent with recent studies showing a role for PATZ1 in the p53 pathway, we showed that ectopic expression of PATZ1 in thyroid cancer cells activates p53-dependent pathways opposing epithelial-mesenchymal transition and cell migration to prevent invasiveness. These results provide insights into a potential tumor-suppressor role of PATZ1 in thyroid cancer progression, and thus may have potential clinical relevance for the prognosis and therapy of thyroid cancer.

Interleukin-8 production by THP-1 cells stimulated by Salmonella enterica serovar Typhimurium porins is mediated by AP-1, NF-κB and MAPK pathways

Interleukin-8 (IL-8) is released in response to inflammatory stimuli, such as bacterial products. Either porins or lipopolysaccharide (LPS) stimulated THP-1 cells to release IL-8 after 24 h. We have previously reported that stimulation of monocytic cells with Salmonella enterica serovar Typhimurium porins led to the activation of mitogen-activated protein kinase cascades and of protein tyrosine kinases (PTKs). In this report, we demonstrate, using two potent and selective inhibitors of MEK activation by Raf-1 (PD-098059) and p38 (SB-203580), that both ERK1/2 and p38 pathways play a key role in the production of IL-8 by porins and LPS. Porin-stimulated expression of activating protein 1 (AP-1) and correlated IL-8 release is also inhibited by PD-098059 or SB-203580 indicating that the Raf-1/MEK1-MEK2/MAPK cascade is required for their activation. Also PTKs modulate the pathway that control IL-8 gene expression, in fact its expression is abolished by tyrphostin. By using N-acetyl-leucinyl-leucinyl-norleucinal-H (ALLN) an inhibitor of nuclear factor-kappaB (NF-kappaB) activity, we also observed IL-8 release modulation. Our results elucidate some of the molecular mechanisms by which AP-1 and NF-kappaB regulate IL-8 release and open new strategies for the design of specific molecules that will modulate IL-8 effects in various infectious diseases.

Role of Pasteurella multocida porin on cytokine expression and release by murine splenocytes

The aim of this study was to verify whether Pasteurella multocida porin can affect the expression and release of IL-1alpha, IL-6, TNF-alpha, IL-4, IFN-gamma, IL-10 and IL-12 by murine splenocytes in vitro. P. multocida porin and lipopolysaccharide (LPS) were able to induce the release of IL-1alpha, IL-6, TNF-alpha, IFN-gamma and IL-12 in a dose-dependent fashion. The greatest release of these cytokines was obtained using P. multocida porin at a concentration of 5 microg ml(-1) and LPS at a concentration of 1 microg ml(-1). The time-courses of release showed that P. multocida LPS was able to stimulate the production of IL-1alpha, IL-6, TNF-alpha, IFN-gamma and IL-12 earlier than porin and at a greater rate. No effect was observed on IL-4 and IL-10 release under the same experimental conditions. P. multocida porin and LPS were also able to up-regulate the mRNA expression of IL-1alpha, IL-6, TNF-alpha, IFN-gamma and IL-12 p40. Our findings suggest that P. multocida porin is able to modulate inflammatory and immunological responses by affecting the release of several cytokines and the expression of their genes.

Th1 and Th2 cell involvement in immune response to Salmonella typhimurium porins

In understanding the regulation of the specific immune response to Salmonella typhimurium, the role of a surface major component (porins) was studied. In this study we demonstrate that purified porins are able to induce a different response to that induced by the porins present on the S. typhimurium cell surface. Porin-treated or orally infected mice show anti-porin antibodies with bactericidal activity. The complete adoptive transfer of resistance to S. typhimurium is achieved only using splenic T cells from survivor mice after experimental infection. After stimulation with specific antigen in vitro CD4+ cells from porin-immunized mice released large amounts of interleukin-4 (IL-4), at a time when CD4+ cells from S. typhimurium-infected mice predominantly secreted interferon-gamma (IFN-gamma). Limiting dilution analysis showed that infection resulted in a higher precursor frequency of IFN-gamma-producing CD4+ T cells and a lower precursor frequency of IL-4-producing CD4+ T cells, while immunization with porins resulted in a higher precursor frequency of IL-4-producing cells and a low frequency of IFN-gamma-producing cells. Analysis of polymerase chain reaction-amplified cDNA from the spleens of infected mice revealed that IFN-gamma, IL-2 and IL-12 p40 mRNA were found 5 days after in vitro challenge and increased after 15 days; IL-10 expression was barely present after both 5 and 15 days, while IL-4 mRNA expression was not detected. In immunized mice, the IL-4 mRNA expression increased after 15 days, IFN-gamma mRNA expression disappeared entirely after 15 days, while IL-2, IL-10 and IL-12 mRNA remained relatively unchanged.

A polymorphism of HMGA1 protects against proliferative diabetic retinopathy by impairing HMGA1-induced VEGFA expression

Diabetic retinopathy (DR) is a major complication of diabetes mellitus, and is the leading cause of blindness in working-age people. Usually, DR progresses from the asymptomatic non-proliferative DR that does not significantly alter vision, to proliferative DR (PDR), which can result in aberrant retinal neovessel formation and blindness. The High-Mobility-Group A1 (HMGA1) protein is a transcriptional master regulator of numerous genes, including metabolic and inflammatory genes, which, by modulating the expression of angiogenic factors, may induce retinal neovascularization, a hallmark of PDR. Herein, we examined the relationship between HMGA1 rs139876191 variant and DR. Results revealed that patients with type 2 diabetes, who were carriers of the HMGA1 rs139876191 variant had a significantly lower risk of developing PDR, compared to non-carrier diabetic patients. From a mechanistic point of view, our findings indicated that, by adversely affecting HMGA1 protein expression and function, the HMGA1 rs139876191 variant played a key role in this protective mechanism by downregulating the expression of vascular endothelial growth factor A (VEGFA), a major activator of neovascularization in DR. These data provide new insights into the pathogenesis and progression of DR, and may offer opportunities for discovering novel biomarkers and therapeutic targets for diagnosis, prevention and treatment of PDR.

Prevalence and incidence of osteoporotic fractures in patients on long-term glucocorticoid treatment for rheumatic diseases: the Glucocorticoid Induced OsTeoporosis TOol (GIOTTO) study

Osteoporosis and fractures are common and invalidating consequences of chronic glucorticoid (GC) treatment. Reliable information regarding the epidemiology of GC induced osteoporosis (GIOP) comes exclusively from the placebo group of randomized clinical trials while observational studies are generally lacking data on the real prevalence of vertebral fractures, GC dosage and primary diagnosis. The objective of this study was to evaluate the prevalence and incidence of osteoporotic fractures and to identify their major determinants (primary disease, GC dosage, bone mineral density, risk factors, specific treatment for GIOP) in a large cohort of consecutive patients aged >21 years, on chronic treatment with GC (≥5 mg prednisone - PN - equivalent) and attending rheumatology centers located all over Italy. Glucocorticoid Induced OsTeoporosis TOol (GIOTTO) is a national multicenter cross-sectional and longitudinal observational study. 553 patients suffering from Rheumatoid Arthritis (RA), Polymyalgia Rheumatica (PMR) and Connective Tissue Diseases (CTDs) and in chronic treatment with GCs were enrolled. Osteoporotic BMD values (T score <-2.5) were observed in 28%, 38% and 35% of patients with CTDs, PMR or RA at the lumbar spine, and in 18%, 29% and 26% at the femoral neck, respectively. Before GC treatment, prevalent clinical fractures were reported by 12%, 37% and 17% of patients with CTDs, PMR, or RA, respectively. New clinical fragility fractures during GC treatment were reported by 12%, 10% and 23% of CTDs, PMR and RA patients, respectively. Vertebral fractures were the prevailing type of fragility fracture. More than 30% of patients had recurrence of fracture. An average of 80% of patients were in supplementation with calcium and/or vitamin D during treatment with GCs. Respectively, 64%, 80%, and 72% of the CTDs, PMR and RA patients were on pharmacological treatment for GIOP, almost exclusively with bisphosphonates. The GIOTTO study might provide relevant contributions to clinical practice, in particular by highlighting and quantifying in real life the prevalence of GIOP and relative fractures, the frequency of the main risk factors, and the currently sub-optimal prevention. Moreover, these results emphasize the importance of the underlying rheumatic disease on the risk of GIOP associated fractures.

Embryonic defects and growth alteration in mice with homozygous disruption of the Patz1 gene

PATZ1 is an emerging cancer-related gene coding for a POZ/AT-hook/kruppel Zinc finger transcription factor, which is lost or misexpressed in human neoplasias. Here, we investigated its role in development exploring wild-type and Patz1-knockout mice during embryogenesis. We report that the Patz1 gene is ubiquitously expressed at early stages of development and becomes more restricted at later stages, with high levels of expression in actively proliferating neuroblasts belonging to the ventricular zones of the central nervous system (CNS). The analysis of embryos in which Patz1 was disrupted revealed the presence of severe defects in the CNS and in the cardiac outflow tract, which eventually lead to a pre-mature in utero death during late gestation or soon after birth. Moreover, the Patz1-null mice showed a general growth retardation, which was consistent with the slower growth rate and the increased susceptibility to senescence of Patz1(-/-) mouse embryonic fibroblasts (MEFs) compared to wild-type controls. Therefore, these results indicate a critical role of PATZ1 in the control of cell growth and embryonic development.

PIT1 upregulation by HMGA proteins has a role in pituitary tumorigenesis

We have previously demonstrated that HMGA1B and HMGA2 overexpression in mice induces the development of GH and prolactin (PRL) pituitary adenomas mainly by increasing E2F1 transcriptional activity. Interestingly, these adenomas showed very high expression levels of PIT1, a transcriptional factor that regulates the gene expression of Gh, Prl, Ghrhr and Pit1 itself, playing a key role in pituitary gland development and physiology. Therefore, the aim of our study was to identify the role of Pit1 overexpression in pituitary tumour development induced by HMGA1B and HMGA2. First, we demonstrated that HMGA1B and HMGA2 directly interact with both PIT1 and its gene promoter in vivo, and that these proteins positively regulate Pit1 promoter activity, also co-operating with PIT1 itself. Subsequently, we showed, by colony-forming assays on two different pituitary adenoma cell lines, GH3 and αT3, that Pit1 overexpression increases pituitary cell proliferation. Finally, the expression analysis of HMGA1, HMGA2 and PIT1 in human pituitary adenomas of different histological types revealed a direct correlation between PIT1 and HMGA expression levels. Taken together, our data indicate a role of Pit1 upregulation by HMGA proteins in pituitary tumours.

Haemophilus influenzae porin contributes to signaling of the inflammatory cascade in rat brain

In the present study we observed that the Haemophilus influenzae type b (Hib) porin, among the different surface bacterial components, is involved in the pathophysiology of bacterial meningitis. This study demonstrates that inoculation of Hib porin into the fourth cerebral ventricle causes the simultaneous expression of interleukin-1alpha (IL-1alpha), tumor necrosis factor alpha (TNF-alpha), and macrophage inflammatory protein 2 (MIP-2) at 6 h after inoculation. At 24 h, the expression of MIP-2 decreases while the expression of IL-1alpha and TNF-alpha increases. The mRNA expression of IL-1alpha, TNF-alpha, and MIP-2 is correlated with injury to the blood-brain barrier as demonstrated by the appearance of serum proteins and leukocytes in cerebrospinal fluid and by the increase in brain water content.

Monocytic activation of protein tyrosine kinase, protein kinase A and protein kinase C induced by porins isolated from Salmonella enterica serovar Typhimurium

OBJECTIVES

In the present study a monocytic cell line, U937, was used to investigate the possible involvement of protein tyrosine kinases (NT-PTKs), protein kinase A (PKA) and protein kinase C (PKC) in cell signaling pathways following Salmonella enterica serovar Typhimurium porin stimulation.

METHODS

Different concentrations of porins and lipopolysaccharide (LPS) were analysed to evaluate changes in PTK activity by a non radioactive tyrosine kinase assay and in PKA and PKC phosphorylation by Western blotting analysis. The inhibitors of PTK, PKA and PKC activation used, were: 3,4-dihydroxybenzylidene-malononitrile (tyrphostin 23), inhibitor of epidermal growth factor (EGF) receptor tyrosine kinase activity; dihychloride (H-89), a selective inhibitor of PKA which is useful to discriminate between the effects of PKC and PKA; diacylglycerol kinase inhibitor II (R59949), which is useful for elucidating roles of PKC; calphostin C, a specific inhibitor of PKC.

RESULTS

Porins of the outer membrane of the ST were isolated to be used as a stimulus in the performed experiments. Following porin treatment, a dose-dependent increase in PTK, PKA and PKC activation was observed. U937 monocytes pretreated with inhibitors induced an evident decrease in PTK activity and PKA and PKC phosphorylation pattern in porin stimulated monocytes.

CONCLUSIONS

Our data support the important role played by NT-PTK, PKA and PKC in transducing the activating signal in macrophages stimulated with porins through the activation of the mitogen-activated protein kinase (MAPK) pathway that participate in the regulation of gene expression.

PATZ1 expression correlates positively with BAX and negatively with BCL6 and survival in human diffuse large B cell lymphomas

Non-Hodgkin lymphomas (NHLs) include a heterogeneous group of diseases, which differ in both cellular origin and clinical behavior. Among the aggressive malignancies of this group, the diffuse large B-cell lymphomas (DLBCLs) are the most frequently observed. They are themselves clinically and molecularly heterogeneous and have been further sub-divided in three sub-types according to different cell of origin, mechanisms of oncogenesis and clinical outcome. Among them, the germinal center B-cell-like (GCB) derives from the germinal center and expresses the BCL6 oncogene. We have previously shown that Patz1-knockout mice develop B-cell neoplasias, suggesting a tumor suppressor role for PATZ1 in human NHLs. Here, by immunohistochemical analysis of a tissue-microarray including 170 NHLs, we found that PATZ1 nuclear expression is down-regulated in follicular lymphomas and DLBCLs. Moreover, consistent with our previous results showing a PATZ1-dependent regulation of BCL6 and BAX transcription, we show that low PATZ1 nuclear expression significantly correlates with high BCL6 expression, mainly in DLBCLs, and with low BAX expression, also considering separately follicular lymphomas and DLBCLs. Finally, by analyzing overall and progression-free survival in DLBCL patients that underwent rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone chemotherapy, low levels of PATZ1 were significantly associated to a worst outcome and demonstrated an independent prognostic factor in multivariate analysis, including known prognostic factors of DLBCL, IPI score and cell of origin (GCB/non-GCB). Therefore, we propose PATZ1 as a new prognostic marker of DLBCLs, which may act as a tumor suppressor by enhancing apoptosis through inhibiting and enhancing transcription of BCL6 and BAX, respectively.

HMGA2 cooperates with either p27kip1 deficiency or Cdk4R24C mutation in pituitary tumorigenesis

We have previously reported a critical role of HMGA proteins in pituitary tumorigenesis since either the Hmga1 or Hmga2 gene overexpression/activation induces the development of mixed growth hormone/prolactin cell pituitary adenomas by activating the E2F transcription factor 1, and then enhancing the G1/S transition of the cell cycle. Consistently, amplification and overexpression of the HMGA2 gene was found in human pituitary prolactinomas. Since impairment of the cell cycle control represents a feature of experimental and human pituitary adenomas, we have investigated the possible synergism between the alterations of other cell cycle regulators, such as p27 deficiency or Cdk4^R24C mutation, with Hmga2 overexpression in pituitary tumorigenesis. Therefore, we crossed the Hmga2/T mice, overexpressing the truncated/active form of the Hmga2 gene, either with the knockout mice for p27^kip1, or with the knockin mice for the Cdk4^R24C mutation, both developing pituitary adenomas. Increased incidence and decreased latency in the development of pituitary lesions appeared in double mutant Hmga2/T;Cdk4^R24C mice, and increased features of invasiveness and atypia were observed in pituitary tumors of both Hmga2/T;p27-ko and Hmga2/T;Cdk4^R24C double mutant mice as compared with single mutant compounds. Interestingly, most of these mice develop pituitary adenomas with high Ki67 index, extrasellar expansion and brain tissue infiltration, representing good mouse models for human aggressive pituitary adenomas. Taken together, the results reported here indicate a cooperation between HMGA2 overexpression and either p27^kip1 or CDK4 impairment in promoting pituitary tumor development and progression.

Induction of tyrosine phosphorylated proteins in THP-1 cells by Salmonella typhimurium, Pasteurella haemolytica and Haemophilus influenzae porins

The effect of porins purified from Salmonella typhimurium, Pasteurella haemolytica and Haemophilus influenzae on induction of tyrosine phosphorylation in THP-1 cells and C3H/HeJ macrophage was investigated. Incubation of porins at concentration of 1.0-5.0 microg ml(-1) with either THP-1 or macrophage from C3H/HeJ mice resulted in tyrosine phosphorylation of specific host cell proteins. After porin stimulation a pattern of tyrosine phosphorylated proteins appeared in the soluble cytoplasmic fraction, in the membrane fraction and in the insoluble protein fraction. The observed effects were dependent on the porin concentrations; they reached a maximal expression at 3 min and declined at 60 min. Porin and lipopolysaccharide treatments induce a similar phosphorylation pattern in all of the three cellular fractions studied. A difference can be observed in the cytoplasmic fraction bands of 50-60 kDa, which are more evident after treatment with lipopolysaccharide, and in the insoluble fraction band of 80 kDa and the cytoplasmic fraction band of 250 kDa, which are more evident after treatment with porins. The events of tyrosine protein phosphorylation were present in macrophage from lipopolysaccaride-hyporesponsive C3H/HeJ mice stimulated with porins, while they were markedly reduced when the cells were stimulated with lipopolysaccharide. Staurosporine, genistein and cytochalasin D induced in the three cellular fractions a different inhibition pattern of tyrosine protein phosphorylation in porin stimulated cells. Porins extracted from the three bacterial species investigated behave in a similar way as stimuli more or less potent; Hib porin seems to be the most powerful stimulator and, moreover, it specifically induces phosphorylation of a 55 kDa band.

Growth hormone modulates IL-alpha and IFN-gamma release by murine splenocytes activated by LPS or porins of Salmonella typhimurium

The effect of growth hormone (GH) on the release of IL-1alpha and IFN-gamma from murine splenocytes was investigated. Their release from splenocytes activated by Salmonella enterica serovar Typhimurium lipopolysaccharide (LPS) 0.5 microg/ml was increased by c. 65% in the presence of GH 100 pg/ml. With splenocytes activated by S. Typhimurium porins 5 microg/ml, GH increased the production of both IL-1alpha and IFN-gamma by c. 56%. Polymyxin treatment abolished the cytokine-releasing activity of LPS but had no effect on the activity of the porin preparation.

Role of Pasteurella multocida, Pasteurella haemolytica and Salmonella typhimurium porins on inducible nitric oxide release by murine macrophages

The aim of this study was to verify whether Pasteurella haemolytica, P. multocida and Salmonella typhimurium porins could affect the inducible nitric oxide synthase (iNOS) expression and nitric oxide (NO) release by murine resident peritoneal macrophages in vitro. We also compared their effect with that elicited by P. haemolytica, P. multocida and S. typhimurium lipopolysaccharide (LPS) whose biological activity is well known. Variations in NO release and iNOS mRNA expression due to variable concentrations of porins were recorded and compared. We also investigated the synergism between bacterial products and interferon gamma (IFN-gamma). With this aim cells were incubated with porins together with murine rIFN-gamma prior to assessing the presence of NO in the supernatant and mRNA analysis. Porins in themselves were not able to induce NO release by resident peritoneal macrophages. Incubation of macrophages with IFN-gamma in the presence of porins increased NO release, whereas incubation in the presence of the arginine analog N(G)-monomethyl-L-arginine (NMA) inhibited NO release. The greatest NO release was obtained using porins at a concentration of 5 microg/mL. Porins, together with IFN-gamma, were also able to upregulate the mRNA expression of iNOS. Our findings suggest that gram-negative porins are able to modulate inflammatory and immunological responses by affecting the release of NO and the expression of iNOS gene in activated macrophages.

The Transcription Regulator Patz1 Is Essential for Neural Stem Cell Maintenance and Proliferation

Proper regulation of neurogenesis, the process by which new neurons are generated from neural stem and progenitor cells (NS/PCs), is essential for embryonic brain development and adult brain function. The transcription regulator Patz1 is ubiquitously expressed in early mouse embryos and has a key role in embryonic stem cell maintenance. At later stages, the detection of Patz1 expression mainly in the developing brain suggests a specific involvement of Patz1 in neurogenesis. To address this point, we first got insights in Patz1 expression profile in different brain territories at both embryonic and postnatal stages, evidencing a general decreasing trend with respect to time. Then, we performed in vivo and ex vivo analysis of Patz1-knockout mice, focusing on the ventricular and subventricular zone, where we confirmed Patz1 enrichment through the analysis of public RNA-seq datasets. Both embryos and adults showed a significant reduction in the number of Patz1-null NS/PCs, as well as of their self-renewal capability, compared to controls. Consistently, molecular analysis revealed the downregulation of stemness markers in NS/PCs derived from Patz1-null mice. Overall, these data demonstrate the requirement of Patz1 for NS/PC maintenance and proliferation, suggesting new roles for this key transcription factor specifically in brain development and plasticity, with possible implications for neurodegenerative disorders and glial brain tumors.

GJB5 association with BRAF mutation and survival in cutaneous malignant melanoma

BACKGROUND

Gap junctional intercellular communication is crucial for epidermal cellular homeostasis. Inability to establish melanocyte-keratinocytes contacts and loss of intercellular junction's integrity may contribute to melanoma development. Connexins, laminins and desmocollins have been implicated in the control of melanoma growth, where their reduced expression has been reported in metastatic lesions.

OBJECTIVES

The aim of this study was to investigate Connexin 31.1 (GJB5) expression and identify any association with BRAF mutational status, melanoma patient prognosis and MAPK inhibitors (MAPKi) treatment.

MATERIAL AND METHODS

GJB5 expression was measured at RNA and protein level in melanoma clinical samples and established cell lines treated or not with BRAF and MEK inhibitors, as well as in cell lines which developed MAPK inhibitors resistance. Findings were further validated and confirmed by analysis of independent datasets.

RESULTS

Our analysis reveals significant downregulation of GJB5 expression in metastatic melanoma lesions compared to primary ones and in BRAF mutated versus BRAF wild-type melanomas. Likewise, GJB5 expression is significantly lower in BRAF^V600E compared with BRAF^WT cell lines and increases upon MAPKi treatment. MAPKi-resistant melanoma cells display a similar expression pattern compared to BRAF^WT cells, with increased GJB5 expression associated with morphological changes. Enhancement of BRAF^V600E expression in BRAF^WT melanoma cells significantly upregulates miR-335-5p expression with consequent downregulation of GJB5, one of its targets. Furthermore, overexpression of miR-335-5p in two BRAF^WT cell lines confirms specific GJB5 protein downregulation. RT-qPCR analysis also revealed upregulation of miR-335 in BRAF^V600E melanoma cells, which is significantly downregulated in cells resistant to MEK inhibitors. Our data were further validated using the TCGA-SKCM dataset, where BRAF mutations associate with increased miR-335 expression and inversely correlate with GJB5 expression. In clinical samples, GJB5 underexpression is also associated with patient overall worse survival, especially at early stages.

CONCLUSION

We identified a significant association between metastases / BRAF mutation and low GJB5 expression in melanoma. Our results identify a novel mechanism of Gap-junctional protein regulation, suggesting a prognostic role for GJB5 in cutaneous melanoma.

Transcriptional and post-transcriptional regulation of transmembrane protein 132A

Transmembrane protein 132A (TMEM132A) was first isolated from rat brain using PCR-selected cDNA subtraction, and it was found to be predominantly expressed in the brain. However, the transcriptional regulation of the TMEM132A gene has not been fully characterized. In this study, we characterized the promoter activity of the 880-bp region upstream of the mouse TMEM132A, identifying several putative sites recognized by transcription factors, which are highly conserved between the mouse and human TMEM132A genes. Using four different mouse cell lines (Neuro2a, NSC-34, NIH3T3, and Raw264.7), we first evaluated the intrinsic levels of TMEM132A mRNA and protein expression. Interestingly, TMEM132A mRNA was expressed in all four cell lines, whereas the protein was negligible in Raw264.7 cells even by transfection of TMEM132A gene. Then, we analyzed the TMEM132A promoter activity using serial deleted constructs, finding it was nearly same pattern in all four cell lines. A mutational analysis of the TMEM132A promoter identified a critical region for its activation just upstream of the transcriptional start site. Finally, we investigated the levels of TMEM132A mRNA and protein after exposure to five different neurotoxic stimuli, including thapsigargin, tunicamycin, serum starvation, homocysteine, and hydrogen peroxide. Treatment with thapsigargin, a calcium modulating agent, markedly attenuated the levels of TMEM132A mRNA and protein in NSC-34 cells. These results give new insight into the mechanisms involved in regulating TMEM132A expression, and suggest that several transcriptional and post-transcriptional pathways regulate TMEM132A expression under developmental and pathophysiological conditions.

Dual Oncogenic/Anti-Oncogenic Role of PATZ1 in FRTL5 Rat Thyroid Cells Transformed by the Ha-RasV12 Oncogene

PATZ1 is a transcriptional factor downregulated in thyroid cancer whose re-expression in thyroid cancer cells leads to a partial reversion of the malignant phenotype, including the capacity to proliferate, migrate, and undergo epithelial-to-mesenchymal transition. We have recently shown that PATZ1 is specifically downregulated downstream of the Ras oncogenic signaling through miR-29b, and that restoration of PATZ1 in Ha-Ras transformed FRTL5 rat thyroid cells is able to inhibit their capacities to proliferate and migrate in vitro. Here, we analyzed the impact of PATZ1 expression on the in vivo tumorigenesis of these cells. Surprisingly, FRTL5-Ras-PATZ1 cells showed enhanced tumor initiation when engrafted in nude mice, even if their tumor growth rate was reduced compared to that of FRTL5-Ras control cells. To further investigate the cause of the enhanced tumor engraftment of FRTL5-Ras-PATZ1 cells, we analyzed the stem-like potential of these cells through their capacity to grow as thyrospheres. The results showed that restoration of PATZ1 expression in these cells increases stem cell markers’ expression and self-renewal ability of the thyrospheres while limiting their growth capacity. Therefore, we suggest that PATZ1 may play a role in enhancing the stem cell potential of thyroid cancer cells, but, at the same time, it impairs the proliferation of non-stem cells.

A Novel Multi-step Virtual Screening for the Identification of Human and Mouse mPGES-1 Inhibitors

We present here the development of a novel virtual screening protocol combining Structure-based and Ligand-based drug design approaches for the identification of mouse mPGES-1 inhibitors. We used the existing 3D structural data of the murine enzyme to hypothesize the inhibitors binding mode, which was the starting point for docking simulations, shape screening, and pharmacophore hypothesis screening. The protocol allowed the identification of 16 mouse mPGES-1 inhibitors with low micromolar activity, which, notably, also inhibit the human enzyme in the same concentration range. The inhibitors predicted binding mode is expected to be the base for the rational drug design of new potent dual species inhibitors of human and murine mPGES-1.

Articular and other Immune-Mediated Extra-Intestinal Manifestations in Inflammatory Bowel Diseases

The articular involvement in patients with inflammatory bowel diseases is included in the group of immune-mediated extra-intestinal manifestations, occurring approximately in a range from 6.2–36% of the patients. This group is also made up of the skin and eyes manifestations, that usually but not invariably are correlated with intestinal inflammatory disease activity. Rheumatic manifestations are the most frequent extra-intestinal findings of this group with a prevalence from 20–50%. They are divided into two different clinical subsets: peripheral and axial joint involvement (including sacroiliitis with or without spondylitis). Peripheral arthritis is the most frequent finding in both Crohn's disease and ulcerative colitis, occurring with a frequency ranging from 17–20%, and it is more common in Crohn's disease. Axial involvement is more common in Crohn's disease (5–22%) than in ulcerative colitis (2–6%) and generally the prevalence of sacroiliitis (asymptomatic and symptomatic) is between 12–20% and of spondylitis is between 2–16%. The IBD is also associated with other rheumatic diseases such as rheumatoid arthritis, Sjogren syndrome, Takayasu arteritis and fibromyalgia. The management of patients with EA requires an active cooperation between gastroenterologists and rheumatologists.

[Type I cryoglobulinemia with a fatal outcome]

Type I cryoglobulinemia, a condition associated with lymphoproliferative disorders, is caused by monoclonal immunoglobulins that precipitate at low temperatures. It mostly involves the skin and pathology study shows no signs of vasculitis. Management is usually based on immunosuppressive drugs associated with plasmapheresis for severe disease. The use of rituximab has recently been described for resistant cases. We present an unusual case of long-standing type I cryoglobulinemia associated with a monoclonal gammopathy of unknown significance. The patient developed extremely severe skin lesions with histological signs of vasculitis. The patient died due to the onset of noncutaneous manifestations of the cryoglobulinemia and complications of the immunosuppressive treatment.