976 resultados para FAD2.2 gene


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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Lysine-ketoglutaratc reductase catalyzes the first step of lysine catabolism in maize (Zea mays L.) endosperm. The enzyme condenses L-lysine and α-ketoglutarate into saccharopine using NADPH as cofactor. It is endosperm-specific and has a temporal pattern of activity, increasing with the onset of kernel development, reaching a peak 20 to 25 days after pollination, and thereafter decreasing as the kernel approaches maturity. The enzyme was extracted from the developing maize endosperm and partially purified by ammonium-sulfate precipitation, anion-exchange chromatography on DEAE-cellulose, and affinity chromatography on Blue-Sepharose CL-6B. The preparation obtained from affinity chromatography was enriched 275-fold and had a specific activity of 411 nanomoles per minute per milligram protein. The native and denaturated enzyme is a 140 kilodalton protein as determined by polyacrylamide gel electrophoresis. The enzyme showed specificity for its substrates and was not inhibited by either aminoethyl-cysteine or glutamate. Steady-state product-inhibition studies revealed that saccharopine was a noncompetitive inhibitor with respect to α-ketoglutarate and a competitive inhibitor with respect to lysine. This is suggestive of a rapid equilibriumordered binding mechanism with a binding order of lysine, α-ketoglutarate, NADPH. The enzyme activity was investigated in two maize inbred lines with homozygous normal and opaque-2 endosperms. The pattern of lysine-ketoglutarate reductase activity is coordinated with the rate of zein accumulation during endosperm development. A coordinated regulation of enzyme activity and zein accumulation was observed in the opaque-2 endosperm as the activity and zein levels were two to three times lower than in the normal endosperm. Enzyme extracted from L1038 normal and opaque-2 20 days after pollination was partially purified by DEAE-cellulose chromatography. Both genotypes showed a similar elution pattern with a single activity peak eluted at approximately 0.2 molar KCL. The molecular weight and physical properties of the normal and opaque-2 enzymes were essentially the same. We suggest that the Opaque-2 gene, which is a transactivator of the 22 kilodalton zein genes, may be involved in the regulation of the lysine-ketoglutarate reductase gene in maize endosperm. In addition, the decreased reductase activity caused by the opaque-2 mutation may explain, at least in part, the elevated concentration of lysine found in the opaque-2 endosperm.

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The American/Asian genotype of Dengue virus type 2 (DENV-2) was introduced into the Americas in the 80′s. Although there is no data showing when this genotype was first introduced into Brazil, it was first detected in Brazil in 1990. After which the virus spread throughout the country and major epidemics occurred in 1998, 2007/08 and 2010. In this study we sequenced 12 DENV-2 genomes obtained from serum samples of patients with dengue fever residing in São José do Rio Preto, São Paulo (SJRP/SP), Brazil, in 2008. The whole open reading frame or envelope sequences were used to perform phylogenetic, phylogeographic and evolutionary analyses. Isolates from SJRP/SP were grouped within one lineage (BR3) close to isolates from Rio de Janeiro, Brazil. Isolates from SJRP were probably introduced there at least in 2007, prior to its detection in the 2008 outbreak. DENV-2 circulation in Brazil is characterized by the introduction, displacement and circulation of three well-defined lineages in different times, most probably from the Caribbean. Thirty-seven unique amino acid substitutions were observed among the lineages, including seven amino acid differences in domains I to III of the envelope protein. Moreover, we dated here, for the first time, the introduction of American/Asian genotype into Brazil (lineage BR1) to 1988/89, followed by the introduction of lineages BR2 (1998-2000) and BR3 (2003-05). Our results show a delay between the introduction and detection of DENV-2 lineages in Brazil, reinforcing the importance and need for surveillance programs to detect and trace the evolution of these viruses. Additionally, Brazilian DENV-2 differed in genetic diversity, date of introduction and geographic origin and distribution in Brazil, and these are important factors for the evolution, dynamics and control of dengue. © 2013 Drumond et al.

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Patients infected with the human immunodeficiency virus (HIV) are at higher risk of developing Epstein-Barr Virus (EBV)-associated lymphomas. The usefulness of monitoring EBV in peripheral blood mononuclear cells (PBMCs) of patients infected with HIV has not been established. The aim of this study was to evaluate the EBV viral load in PBMCs, the frequency of viral genotypes, and the presence of the 30-bp deletion in the BNLF-1 gene. DNA samples from 156 patients attending the HIV/AIDS Day Clinic at Botucatu School of Medicine, Sao Paulo State University were evaluated. The EBV viral load was detectable by real time PCR in 123/156 (78.8%) cases and was higher in patients not receiving antiretroviral treatment or under therapeutic failure than in patients under successful highly active antiretroviral therapy (HAART) (P=0.0076). Overall, the profile of patients with high EBV viral load included elevated HIV viremia (P=0.0005), longer time of HIV diagnosis (P=0.0026), and increased levels of T CD8 + lymphocytes (P=0.0159). The successful amplification of the EBNA-2 gene by nested-PCR was achieved in 95 of 123 (77.2%) cases, of which 75.8% were EBV-1, 9.5% EBV-2, and 14.7% were co-infected with both EBV-1 and -2. The analysis of the BNLF-1 gene was possible in 99 of 123 (80.5%) cases, of which 50.5% had the 30-bp deletion. EBV-1 was more common than EBV-2, which may reflect the fact that the cohort was predominantly Caucasian and heterosexual. J. Med. Virol. 85:2110-2118, 2013. © 2013 Wiley Periodicals, Inc.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Because GABA(A) receptors containing alpha 2 subunits are highly represented in areas of the brain, such as nucleus accumbens (NAcc), frontal cortex, and amygdala, regions intimately involved in signaling motivation and reward, we hypothesized that manipulations of this receptor subtype would influence processing of rewards. Voltage-clamp recordings from NAcc medium spiny neurons of mice with alpha 2 gene deletion showed reduced synaptic GABA(A) receptor-mediated responses. Behaviorally, the deletion abolished cocaine`s ability to potentiate behaviors conditioned to rewards (conditioned reinforcement), and to support behavioral sensitization. In mice with a point mutation in the benzodiazepine binding pocket of alpha 2-GABA(A) receptors (alpha 2H101R), GABAergic neurotransmission in medium spiny neurons was identical to that of WT (i.e., the mutation was silent), but importantly, receptor function was now facilitated by the atypical benzodiazepine Ro 15-4513 (ethyl 8-amido-5,6-dihydro-5-methyl-6-oxo-4H-imidazo [1,5-a] [1,4] benzodiazepine-3-carboxylate). In alpha 2H101R, but not WT mice, Ro 15-4513 administered directly into the NAcc-stimulated locomotor activity, and when given systemically and repeatedly, induced behavioral sensitization. These data indicate that activation of alpha 2-GABA(A) receptors (most likely in NAcc) is both necessary and sufficient for behavioral sensitization. Consistent with a role of these receptors in addiction, we found specific markers and haplotypes of the GABRA2 gene to be associated with human cocaine addiction.

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Imbalanced matrix metalloproteinase (MMP) expression, including MMP-2, has been demonstrated in pre-eclampsia. However, little is known about the effect of polymorphisms in MMP-2 gene on hypertensive disorders of pregnancy. We examined whether two functional MMP-2 polymorphisms (g.-1306C>T and g.-735C>T) are associated with pre-eclampsia and/or gestational hypertension and whether these polymorphisms affect therapeutic responses in women with these conditions. We studied 216 healthy pregnant women (HP), 185 patients with gestational hypertension (GH) and 216 patients with pre-eclampsia (PE). They were stratified as responsive or non-responsive to antihypertensive therapy according to clinical and laboratorial parameters of therapeutic responsiveness. Genomic DNA was extracted from whole blood and genotypes for g-1306C>T and g.-735C>T polymorphisms were determined by real-time PCR using Taqman allele discrimination assays. Haplotype frequencies were inferred using the PHASE 2.1 program. The distributions of MMP-2 genotypes and haplotypes were similar in HP, GH and PE patients (p > 0.05). In addition, we found no significant differences in MMP-2 genotype or haplotype frequencies when GH or PE patients were classified as responsive or non-responsive to antihypertensive therapy (p > 0.05). Our results suggest that MMP-2 polymorphisms do not affect the susceptibility to hypertensive disorders of pregnancy. In parallel, MMP-2 polymorphisms apparently do not affect the responsiveness to antihypertensive therapy of women with these hypertensive disorders of pregnancy.

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Background: Matrix metalloproteinases (MMPs) play important roles in the pathophysiology of renal diseases, and imbalanced MMP-2 and its endogenous inhibitor (the tissue inhibitor of metalloproteinases-2; TIMP-2) are implicated in the vascular alterations of end-stage kidney disease (ESKD) patients. We have examined whether MMP-2 gene polymorphisms and haplotypes modify MMP-2 and TIMP-2 levels in ESKD patients as well as the effects of hemodialysis on the concentrations of these biomarkers. Methods: We determined MMP-2 and TIMP-2 plasma levels by gelatin zymography and ELISA, respectively, in 98 ESKD patients and in 38 healthy controls. Genotypes for two relevant MMP-2 polymorphisms (C-T-1306 and C-T-735 in the promoter region) were determined by TaqMan (R) allele discrimination assay and real-time polymerase chain reaction. The software program PHASE 2.1 was used to estimate the haplotype frequencies. Results: We found increased plasma MMP-2 and TIMP-2 levels in ESKD patients compared to controls (p<0.05), and hemodialysis decreased MMP-2 (but not TIMP-2) levels (p<0.05). The T allele for the C-T-735 polymorphism and the C-T haplotype were associated with higher MMP-2 (but not TIMP-2) levels (p<0.05), whereas the C-T-1306 had no effects. Hemodialysis decreased MMP-2 (but not TIMP-2) levels independently of MMP-2 genotypes or haplotypes (p<0.05). Conclusions: MMP-2 genotypes or haplotypes modify MMP-2 levels in ESKD patients, and may help to identify patients with increased MMP-2 activity in plasma. Hemodialysis reduces MMP-2 levels independently of MMP-2 genetic variants. Copyright (C) 2012 S. Karger AG, Basel

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Most of the patients with 5 alpha-RD 2 deficiency are reared in the female social sex due to their severely undervirilized external genitalia but similar to 60% who have not been submitted to orchiectomy in childhood undergo male social sex change at puberty. In our cohort of 30 cases from 18 families, all subjects were registered in the female social sex except for two children-one who had an affected uncle and the other who was diagnosed before being registered. The majority of the patients were satisfied with the long-term results of their treatment and surprisingly, penile length was not associated with satisfactory or unsatisfactory sexual activity. Steroid 5 alpha-RD2 deficiency should be included in the differential diagnosis of all newborns with 46,XY DSD with normal testosterone production before gender assignment or any surgical intervention because these patients should be considered males at birth.

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We examined whether two functional polymorphisms (g.-1306 C> T and g.-735 C>T) in matrix metalloproteinase (MMP)-2 gene are associated with preeclampsia (PE) or gestational hypertension (GH), and whether they modify MMP-2 or tissue inhibitor of metalloproteinase (TIMP)-2 plasma concentrations in these hypertensive disorders of pregnancy. We studied 130 healthy pregnant (HP), 130 pregnant with GH, and 133 pregnant with PE. Genomic DNA was extracted from whole blood and genotypes for g.-1306 C>T and g.-735 C>T polymorphisms were determined by Real Time-PCR, using Taqman allele discrimination assays. Haplotypes were inferred using the PHASE program. Plasma MMP-2 and TIMP-2 concentrations were measured by ELISA. The main findings were that pregnant with PE have higher plasma MMP-2 and TIMP-2 concentrations than HP (P<0.05), although the MMP-2/TIMP-2 ratios were similar (P>0.05). Moreover, pregnant with GH have elevated plasma MMP-2 levels and MMP-2/TIMP-2 ratios compared to HP (P<0.05). While MMP-2 genotypes and haplotypes are not linked with hypertensive disorders of pregnancy, MMP-2 genotypes and haplotypes are associated with significant alterations in plasma MMP-2 and TIMP-2 concentrations in preeclampsia (P<0.05). Our findings may help to understand the relevance of MMP-2 and its genetic polymorphisms to the pathophysiology of hypertensive disorders of pregnancy. It is possible that patients with PE and the MMP-2 haplotype combining the C and T alleles for the g.-1306 C>T and g.-735 C>T polymorphisms may benefit from the use of MMPs inhibitors such as doxycycline. However, this possibility remains to be determined. (C) 2012 Elsevier Inc. All rights reserved.

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Despite new methods and combined strategies, conventional cancer chemotherapy still lacks specificity and induces drug resistance. Gene therapy can offer the potential to obtain the success in the clinical treatment of cancer and this can be achieved by replacing mutated tumour suppressor genes, inhibiting gene transcription, introducing new genes encoding for therapeutic products, or specifically silencing any given target gene. Concerning gene silencing, attention has recently shifted onto the RNA interference (RNAi) phenomenon. Gene silencing mediated by RNAi machinery is based on short RNA molecules, small interfering RNAs (siRNAs) and microRNAs (miRNAs), that are fully o partially homologous to the mRNA of the genes being silenced, respectively. On one hand, synthetic siRNAs appear as an important research tool to understand the function of a gene and the prospect of using siRNAs as potent and specific inhibitors of any target gene provides a new therapeutical approach for many untreatable diseases, particularly cancer. On the other hand, the discovery of the gene regulatory pathways mediated by miRNAs, offered to the research community new important perspectives for the comprehension of the physiological and, above all, the pathological mechanisms underlying the gene regulation. Indeed, changes in miRNAs expression have been identified in several types of neoplasia and it has also been proposed that the overexpression of genes in cancer cells may be due to the disruption of a control network in which relevant miRNA are implicated. For these reasons, I focused my research on a possible link between RNAi and the enzyme cyclooxygenase-2 (COX-2) in the field of colorectal cancer (CRC), since it has been established that the transition adenoma-adenocarcinoma and the progression of CRC depend on aberrant constitutive expression of COX-2 gene. In fact, overexpressed COX-2 is involved in the block of apoptosis, the stimulation of tumor-angiogenesis and promotes cell invasion, tumour growth and metastatization. On the basis of data reported in the literature, the first aim of my research was to develop an innovative and effective tool, based on the RNAi mechanism, able to silence strongly and specifically COX-2 expression in human colorectal cancer cell lines. In this study, I firstly show that an siRNA sequence directed against COX-2 mRNA (siCOX-2), potently downregulated COX-2 gene expression in human umbilical vein endothelial cells (HUVEC) and inhibited PMA-induced angiogenesis in vitro in a specific, non-toxic manner. Moreover, I found that the insertion of a specific cassette carrying anti-COX-2 shRNA sequence (shCOX-2, the precursor of siCOX-2 previously tested) into a viral vector (pSUPER.retro) greatly increased silencing potency in a colon cancer cell line (HT-29) without activating any interferon response. Phenotypically, COX-2 deficient HT-29 cells showed a significant impairment of their in vitro malignant behaviour. Thus, results reported here indicate an easy-to-use, powerful and high selective virus-based method to knockdown COX-2 gene in a stable and long-lasting manner, in colon cancer cells. Furthermore, they open up the possibility of an in vivo application of this anti-COX-2 retroviral vector, as therapeutic agent for human cancers overexpressing COX-2. In order to improve the tumour selectivity, pSUPER.retro vector was modified for the shCOX-2 expression cassette. The aim was to obtain a strong, specific transcription of shCOX-2 followed by COX-2 silencing mediated by siCOX-2 only in cancer cells. For this reason, H1 promoter in basic pSUPER.retro vector [pS(H1)] was substituted with the human Cox-2 promoter [pS(COX2)] and with a promoter containing repeated copies of the TCF binding element (TBE) [pS(TBE)]. These promoters were choosen because they are partculary activated in colon cancer cells. COX-2 was effectively silenced in HT-29 and HCA-7 colon cancer cells by using enhanced pS(COX2) and pS(TBE) vectors. In particular, an higher siCOX-2 production followed by a stronger inhibition of Cox-2 gene were achieved by using pS(TBE) vector, that represents not only the most effective, but also the most specific system to downregulate COX-2 in colon cancer cells. Because of the many limits that a retroviral therapy could have in a possible in vivo treatment of CRC, the next goal was to render the enhanced RNAi-mediate COX-2 silencing more suitable for this kind of application. Xiang and et al. (2006) demonstrated that it is possible to induce RNAi in mammalian cells after infection with engineered E. Coli strains expressing Inv and HlyA genes, which encode for two bacterial factors needed for successful transfer of shRNA in mammalian cells. This system, called “trans-kingdom” RNAi (tkRNAi) could represent an optimal approach for the treatment of colorectal cancer, since E. Coli in normally resident in human intestinal flora and could easily vehicled to the tumor tissue. For this reason, I tested the improved COX-2 silencing mediated by pS(COX2) and pS(TBE) vectors by using tkRNAi system. Results obtained in HT-29 and HCA-7 cell lines were in high agreement with data previously collected after the transfection of pS(COX2) and pS(TBE) vectors in the same cell lines. These findings suggest that tkRNAi system for COX-2 silencing, in particular mediated by pS(TBE) vector, could represent a promising tool for the treatment of colorectal cancer. Flanking the studies addressed to the setting-up of a RNAi-mediated therapeutical strategy, I proposed to get ahead with the comprehension of new molecular basis of human colorectal cancer. In particular, it is known that components of the miRNA/RNAi pathway may be altered during the progressive development of colorectal cancer (CRC), and it has been already demonstrated that some miRNAs work as tumor suppressors or oncomiRs in colon cancer. Thus, my hypothesis was that overexpressed COX-2 protein in colon cancer could be the result of decreased levels of one or more tumor suppressor miRNAs. In this thesis, I clearly show an inverse correlation between COX-2 expression and the human miR- 101(1) levels in colon cancer cell lines, tissues and metastases. I also demonstrate that the in vitro modulating of miR-101(1) expression in colon cancer cell lines leads to significant variations in COX-2 expression, and this phenomenon is based on a direct interaction between miR-101(1) and COX-2 mRNA. Moreover, I started to investigate miR-101(1) regulation in the hypoxic environment since adaptation to hypoxia is critical for tumor cell growth and survival and it is known that COX-2 can be induced directly by hypoxia-inducible factor 1 (HIF-1). Surprisingly, I observed that COX-2 overexpression induced by hypoxia is always coupled to a significant decrease of miR-101(1) levels in colon cancer cell lines, suggesting that miR-101(1) regulation could be involved in the adaption of cancer cells to the hypoxic environment that strongly characterize CRC tissues.

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The cathepsin enzymes represent an important family of lysosomal proteinases with a broad spectrum of functions in many, if not in all, tissues and cell types. In addition to their primary role during the normal protein turnover, they possess highly specific proteolytic activities, including antigen processing in the immune response and a direct role in the development of obesity and tumours. In pigs, the involvement of cathepsin enzymes in proteolytic processes have important effects during the conversion of muscle to meat, due to their influence on meat texture and sensory characteristics, mainly in seasoned products. Their contribution is fundamental in flavour development of dry-curing hams. However, several authors have demonstrated that high cathepsin activity, in particular of cathepsin B, is correlated to defects of these products, such as an excessive meat softness together with abnormal free tyrosine content, astringent or metallic aftertastes and formation of a white film on the cut surface. Thus, investigation of their genetic variability could be useful to identify DNA markers associated with these dry cured hams parameters, but also with meat quality, production and carcass traits in Italian heavy pigs. Unfortunately, no association has been found between cathepsin markers and meat quality traits so far, in particular with cathepsin B activity, suggesting that other genes, besides these, affect meat quality parameters. Nevertheless, significant associations were observed with several carcass and production traits in pigs. A recent study has demonstrated that different single nucleotide polymorphisms (SNPs) localized in cathepsin D (CTSD), F (CTSF), H and Z genes were highly associated with growth, fat deposition and production traits in an Italian Large White pig population. The aim of this thesis was to confirm some of these results in other pig populations and identify new cathepsin markers in order to evaluate their effects on cathepsin activity and other production traits. Furthermore, starting from the data obtained in previous studies on CTSD gene, we also analyzed the known polymorphism located in the insulin-like growth factor 2 gene (IGF2 intron3-g.3072G>A). This marker is considered the causative mutation for the quantitative trait loci (QTL) affecting muscle mass and fat deposition in pigs. Since IGF2 maps very close to CTSD on porcine chromosome (SSC) 2, we wanted to clarify if the effects of the CTSD marker were due to linkage disequilibrium with the IGF2 intron3-g.3072G>A mutation or not. In the first chapter, we reported the results from these two SSC2 gene markers. First of all, we evaluated the effects of the IGF2 intron3-g.3072G>A polymorphism in the Italian Large White breed, for which no previous studies have analysed this marker. Highly significant associations were identified with all estimated breeding values for production and carcass traits (P<0.00001), while no effects were observed for meat quality traits. Instead, the IGF2 intron3-g.3072G>A mutation did not show any associations with the analyzed traits in the Italian Duroc pigs, probably due to the low level of variability at this polymorphic site for this breed. In the same Duroc pig population, significant associations were obtained for the CTSD marker for all production and carcass traits (P < 0.001), after excluding possible confounding effects of the IGF2 mutation. The effects of the CTSD g.70G>A polymorphism were also confirmed in a group of Italian Large White pigs homozygous for the IGF2 intron3-g.3072G allele G (IGF2 intron3-g.3072GG) and by haplotype analysis between the markers of the two considered genes. Taken together, all these data indicated that the IGF2 intron3-g.3072G>A mutation is not the only polymorphism affecting fatness and muscle deposition in pigs. In the second chapter, we reported the analysis of two new SNPs identified in cathepsin L (CTSL) and cathepsin S (CTSS) genes and the association results with meat quality parameters (including cathepsin B activity) and several production traits in an Italian Large White pig population. Allele frequencies of these two markers were evaluated in 7 different pig breeds. Furthermore, we mapped using a radiation hybrid panel the CTSS gene on SSC4. Association studies with several production traits, carried out in 268 Italian Large White pigs, indicated positive effects of the CTSL polymorphism on average daily gain, weight of lean cuts and backfat thickness (P<0.05). The results for these latter traits were also confirmed using a selective genotype approach in other Italian Large White pigs (P<0.01). In the 268 pig group, the CTSS polymorphism was associated with feed:gain ratio and average daily gain (P<0.05). Instead, no association was observed between the analysed markers and meat quality parameters. Finally, we wanted to verify if the positive results obtained for the cathepsin L and S markers and for other previous identified SNPs (cathepsin F, cathepsin Z and their inhibitor cystatin B) were confirmed in the Italian Duroc pig breed (third chapter). We analysed them in two groups of Duroc pigs: the first group was made of 218 performance-tested pigs not selected by any phenotypic criteria, the second group was made of 100 Italian Duroc pigs extreme and divergent for visible intermuscular fat trait. In the first group, the CTSL polymorphism was associated with weight of lean cuts (P<0.05), while suggestive associations were obtained for average daily gain and backfat thickness (P<0.10). Allele frequencies of the CTSL gene marker also differed positively among the visible intermuscular extreme tails. Instead, no positive effects were observed for the other DNA markers on the analysed traits. In conclusion, in agreement with the present data and for the biological role of these enzymes, the porcine CTSD and CTSL markers: a) may have a direct effect in the biological mechanisms involved in determining fat and lean meat content in pigs, or b) these markers could be very close to the putative functional mutation(s) present in other genes. These findings have important practical applications, in particular the CTSD and CTSL mutations could be applied in a marker assisted selection (MAS) both in the Italian Large White and Italian Duroc breeds. Marker assisted selection could also increase in efficiency by adding information from the cathepsin S genotype, but only in the Italian Large White breed.

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Cyclooxygenase-2/Carbonic anhydrase-IX up-regulation promotes invasive potential and hypoxia survival in colorectal cancer cells Purpose: Cyclooxygenase-2 (COX-2) is a major mediator of inflammation, playing a pivotal role in colorectal carcinogenesis. Hypoxia is an universal hallmark of solid tumour in vivo. This investigation was prompted by the observation that in colorectal cancer cells the expression of COX-2 protein is positively correlated with that of the hypoxia survival gene Carbonic Anhydrase-IX (CA-IX). Experimental Design: Since COX-2 gene expression and activity is increased in hypoxia, and that CA-IX is expressed also in normoxia in colorectal cancer cells, we tested the hypothesis that COX-2 activity in normoxia, as well as in hypoxia may be functionally linked to that of CA-IX gene. We investigated the role of COX-2 and CA-IX in colorectal cancer cell lines. In this regard, we performed RNA interference to knockdown COX-2 gene in vitro and immunohistochemistry to evaluate the protein expression of COX-2 and CA-IX in human colon cancer tissue specimens ex vivo. Results: We found that COX-2, by PGE2 production, controls CA-IX gene expression in an ERK dependent manner. In line with this finding, we also showed that the COX-2 inhibition by a specific short harpin COX-2 RNA (shCOX-2) or by a specific drug (SC-236), down-regulated CA-IX expression in colon cancer cells. We then exposed colon cancer cells to hypoxia stimuli and found that COX-2/CA-IX interplay promoted hypoxia survival. Moreover, we also report that COX-2/CA-IX interplay triggers Matrix Metalloproteinase 2/9 (MMP-2/9) activation and enhances the invasiveness of colorectal cancer cells. Thus given our above observations, we found that CA-IX and COX-2 protein expressions correlate with more aggressive stage colorectal cancer tissues ex vivo. Conclusions: Taken together these data indicate that COX-2/CA-IX interplay promotes an aggressive phenotype (hypoxia survival and invasiveness) which can be modulated in vitro by COX-2 selective inhibition and which may play a role in determining the biological aggressiveness of colorectal tumours. Moreover, in vitro and ex vivo data also suggest that the signatures of inflammation (COX-2) and hypoxia (CA-IX) may be difficult to be disentangled in colon cancer, being both responsible for the up-regulation of the same pathways.