22 research outputs found

    Deregulated expression of Nucleophosmin 1 in gastric cancer and its clinicopathological implications

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    Background: the process of gastric carcinogenesis still remains to be elucidated. the identification of genes related to this process may help to reduce mortality rates through early diagnosis and the development of new anticancer therapies. Nucleophosmin 1 (NPM1) acts in ribosome biogenesis, centrosome duplication, maintenance of genomic stability, and embryonic development. Recently, NPM1 has been implicated in the tumorigenesis processes. Here, we evaluated NPM1 gene and protein expression in gastric tumors and in corresponding non-neoplastic gastric samples.Methods: NPM1 protein expression was determined by Western blot in 17 pairs of gastric tumors and corresponding non-neoplastic gastric tissue. the protein immunoreactivity was observed in 12 tumor samples. mRNA expression was evaluated by reverse transcription quantitative polymerase chain reaction (RT-qPCR) in 22 pairs of gastric tumors and in matched non-neoplastic gastric tissue.Results: NPM1 protein expression was significantly reduced in gastric cancer samples compared to matched non-neoplastic gastric samples (P = 0.019). the protein level of NPM1 was reduced at least 1.5-fold in 35% of tumors compared to paired non-neoplastic gastric tissue. However, NPM1 immunoreactivity was detected in neoplastic and non-neoplastic cells, including in intestinal metaplastic, gastritis and inflammatory cells. NPM1 was mainly expressed in nucleus and nucleolus subcellular compartments. the staining intensity and the percentage of immunoreactive cells varied among the studied cases. the NPM1 mRNA level was reduced at least 1.5-fold in 45.5% of samples and increased in 27.3% of samples. An inverse correlation between protein and mRNA expression was detected (r = -0.509, P = 0.037). Intestinal-type gastric cancer presented higher mRNA levels than diffuse-type (P = 0.026). However, reduced NPM1 protein expression was associated with intestinal-type gastric cancer compared to matched non-neoplastic gastric samples (P = 0.018). in addition, tumors from patients with known distant metastasis presented reduced NPM1 protein levels compared to tumors from patients without distant metastasis (P < 0.001).Conclusion: Although the expression of NPM1 is heterogeneous in gastric tumors, our results suggest that NPM1 down-regulation may have a role in gastric carcinogenesis and may help in the selection of anticancer treatment strategies.Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Universidade Federal de São Paulo, Dept Morphol & Genet, Div Genet, BR-04023900 São Paulo, BrazilUniversidade Federal de São Paulo, Dept Orthoped & Traumatol, BR-04038031 São Paulo, BrazilUniv São Paulo, Sch Med, Dept Radiol, Expt Oncol Lab, BR-01246903 São Paulo, BrazilSão Paulo State Canc Inst, Ctr Translat Oncol, BR-01246000 São Paulo, BrazilFed Univ Para, Joao de Barros Barreto Univ Hosp, Oncol Res Ctr, BR-60673000 Belem, Para, BrazilFed Univ Para, Inst Biol Sci, Human Cytogenet Lab, BR-66073000 Belem, Para, BrazilUniversidade Federal de São Paulo, Dept Morphol & Genet, Div Genet, BR-04023900 São Paulo, BrazilUniversidade Federal de São Paulo, Dept Orthoped & Traumatol, BR-04038031 São Paulo, BrazilWeb of Scienc

    Prohibitin Expression Deregulation in Gastric Cancer Is Associated with the 3 ' Untranslated Region 1630 C > T Polymorphism and Copy Number Variation

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    PHB is a reported oncogene and tumor suppressor in gastric cancer. Here, we evaluated whether the PHB copy number and the rs6917 polymorphism affect its expression in gastric cancer. Down-regulation and up-regulation of PHB were observed in the evaluated tumors. Reduced expression was associated with tumor dedifferentiation and cancer initiation. the T allele of the rs6917 polymorphism was associated with reduced PHB mRNA levels. Moreover, the up-regulation of PHB appeared to be regulated by the gain of additional gene copies. Thus, PHB copy number variation and differential expression of the rs6917 polymorphism may play a role in PHB transcriptional regulation.Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Universidade Federal de São Paulo, Disciplina Genet, Dept Morfol & Genet, São Paulo, BrazilUniversidade Federal de São Paulo, Dept Ortopedia & Traumatol, São Paulo, BrazilUniversidade Federal de São Paulo, Fac Med, Dept Radiol, Lab Oncol Expt, São Paulo, BrazilInst Canc Estado São Paulo, Ctr Invest Translat Oncol, São Paulo, BrazilFed Univ Para, Hosp Univ Joao Barros Barreto, BR-66059 Belem, Para, BrazilFed Univ Para, Inst Ciencias Biol, Lab Citogenet Humana, BR-66059 Belem, Para, BrazilUniversidade Federal de São Paulo, Disciplina Genet, Dept Morfol & Genet, São Paulo, BrazilUniversidade Federal de São Paulo, Dept Ortopedia & Traumatol, São Paulo, BrazilUniversidade Federal de São Paulo, Fac Med, Dept Radiol, Lab Oncol Expt, São Paulo, BrazilWeb of Scienc

    Alterações genômicas e perfil de expressão gênica global em leiomiomas uterinos

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    Os Leiomiomas Uterinos (LU) são os tumores benignos mais comuns do trato genital feminino afetando entre 25-30% das mulheres em idade reprodutiva. Embora com etiologia pouca conhecida, estes tumores constituem um importante problema de saúde pública, sendo a principal indicação para histerectomia. Aproximadamente 40- 50% dos LU apresentam anormalidades citogenéticas não randômicas, portanto, a outra metade pode conter alterações submicroscópicas, como as alterações no número de cópias de DNA (CNVs). Estudos de expressão gênica globais têm revelado o envolvimento de genes que participam das vias de proliferação e ciclo celular, do ácido retinóico, sinalização TGF-beta e IGF-1 em resposta ao estrógeno e a progesterona. Entretanto, poucos genes mapeados em regiões de CNVs foram diretamente associados com o desenvolvimento dos LU. O objetivo deste estudo foi investigar alterações no número de cópias de DNA em pacientes com LU múltiplos e únicos. Utilizando a técnica de CGH array, foram avaliadas 80 amostras de LU obtidas de 56 pacientes. O perfil de expressão gênica global foi investigado em 51 amostras com o objetivo de identificar genes diferencialmente expressos em relação ao miométrio adjacente (MM). Posteriormente, os dados genômicos e transcriptômicos foram integrados com o objetivo de identificar CNVs funcionais que possam estar associadas ao fenótipo tumoral, sendo esta análise importante para a descrição de novos marcadores moleculares e possíveis alvos terapêuticos. Amostras de DNA e RNA foram obtidas dos LU e MM de pacientes nas fases proliferativa e secretora do ciclo menstrual. As 80 amostras de DNA tumoral e DNA referência universal foram digeridas, marcadas e hibridadas em lâminas Agilent Human 4x44K CGH Microarrays. Os dados foram...Uterine leiomyomas (UL) are the most common benign tumors affecting between 25- 30% of women in reproductive age. Although little is known about its etiology, these tumors represent a major problem in public health being the main indication for hysterectomy. About 40-50% have nonrandom cytogenetic abnormalities, thus half of these tumors may have submicroscopic alterations, as well as copy number variations (CNVs). Global gene expression studies have shown genes that act in proliferation and cell cycle process, retinoic acid, TGF-beta and IGF-1 signaling in response to estrogen and progesterone. However, few genes mapped at CNVs regions were directly associated with the UL development. The aim of this study was to investigate DNA copy number alterations in patients with multiple and unique UL. For this, the CGH array technique was employed in 80 samples obtained from 56 patients. The global gene expression profile was investigated in 51 samples to identify differentially expressed genes in relation to adjacent myometrium (MM). In order to identify functional CNVs that might be associated with tumor phenotype, the genomic and transcriptomic data were evaluated using integrative analysis, which is crucial to describe new molecular markers and putative therapeutic targets. DNA and RNA samples were obtained from UL and MM of patients in the proliferative and secretory menstrual cycle phases. Eighty DNA samples and reference DNA were digested, labeled and hybridized in Agilent Human CGH Microarrays 4x44K slides. Data were analyzed by Nexus v5.0 with the Rank Segmentation algorithm and 1.00 E-4 threshold. The classification of nonrandom CNVs (P ≤ 0.05) was the presence in more than 10% cases and exclusion of CNVs detected in more than 5% of the population... (Complete abstract click electronic access below)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

    Genetic polymorphisms associated with steroids metabolism and insulin action in polycystic ovary syndrome

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    Polycystic ovary syndrome (PCOS) is an endocrinopathy associated with infertility, diabetes and cardiovascular events. This study aimed to correlate polymorphisms of genes involved in the biosynthesis and metabolism of steroids and insulin action (CYP17A1, CYP19A1, AR, ESR1, ESR2, INSR, IGF2 and PAI1) with clinical and biochemical parameters of PCOS. DNA was extracted from peripheral blood samples obtained from 117 PCOS and 105 healthy women. The PAI1 insertion/deletion (-675 ins/delG) polymorphism (rs1799768) was genotyped by PCR-SSCP. CYP19A1 [TTTA](n), AR [CAG](n), ESR1 [TA](n), and ESR2 [CA](n) genes were evaluated by PCR-based GeneScan analysis, while CYP17A1 5'UTR (rs743572), INSR 1058 CT (rs1799817), and IGF2 3'UTR GA (rs680) polymorphisms were evaluated by PCR-RFLP. The results showed a prevalence of PAI1 4G5G+4G4G genotypes in PCOS (p=0.025). Younger PCOS women showed a predominance of CT+TT, GA+AA and 4G5G+4G4G genotypes of INSR, IGF2, and PAI1 (p=0.0499, p=0.0300, p=0.0350, respectively). AR shorter alleles (<= 20 repeats) were significantly associated with higher serum levels of total testosterone (TT, p=0.0086). In conclusion, PAI1 polymorphism seems to be associated with the risk of PCOS development. Younger PCOS women had specific genotypes of INSR, IGF2 and PAI1 genes. AR shorter alleles can be associated with higher serum levels of TT in PCOS patients.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

    Polymorphisms of CYP17A1, CYP19, and androgen in Brazilian women with uterine leiomyomas

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    Background: Uterine leiomyomas are common, benign, smooth muscle tumors representing a significant public health problem. The aim of this study was to investigate CYP17A1, CYP19, and androgen (AR) polymorphisms, their relative risks for uterine leiomyomas and possible associations with clinical parameters.Methods: Uterine leiomyoma tissues and blood samples were obtained from 87 patients, as were peripheral blood samples from 68 control women. Clinical data were recorded in both groups. The CYP17A1 (rs743572) polymorphism was analyzed by PCR-RFLP, and the CYP19 [TTTA](n) repeat and AR [CAG](n) repeat were analyzed using PCR-based GeneScan analysis. AR loss of heterozygosity (LOH) and microsatellite instability were also evaluated, while samples exhibiting LOH were analyzed for X inactivation.Results: Clinical parameters related to disease development did not differ between cases and controls. CYP17A1 *A2/*A2 genotype was prevalent in non-white women. CYP17A1, CYP19, and AR genotypes and alleles did not differ between groups. However, alleles presenting [TTTA](7) repeats in intron 4 of CYP19 were more frequent in the control group (p=0.0550). Shorter and longer [CAG]n repeat alleles of AR were exclusive to the leiomyoma group. The LOH assay showed allele losses at AR locus in four informative tumors and X chromosome inactivation analysis revealed that these tumors retained the active allele.Conclusions: The overall lack of association between uterine leiomyomas with polymorphisms involved in steroidogenesis or steroid metabolism is consistent with the hypothesis that these polymorphisms do not substantially contribute to the development of these tumors

    MicroRNA-195 acts as an anti-proliferative miRNA in human melanoma cells by targeting Prohibitin 1

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    Abstract Background Melanoma is the most lethal type of skin cancer. Since chemoresistance is a significant barrier, identification of regulators affecting chemosensitivity is necessary in order to create new forms of intervention. Prohibitin 1 (PHB1) can act as anti-apoptotic or tumor suppressor molecule, depending on its subcellular localization. Our recent data shown that accumulation of PHB1 protects melanoma cells from chemotherapy-induced cell death. Lacking of post-transcriptional regulation of PHB1 could explain this accumulation. Interestingly, most of melanoma patients have down-regulation of microRNA-195. Here, we investigate the role of miR-195, its impact on PHB1 expression, and on chemosensitivity in melanoma cells. Methods TCGA-RNAseq data obtained from 341 melanoma patient samples as well as a panel of melanoma cell lines were used in an expression correlation analysis between PHB1 and predicted miRNAs. miR-195 impact on PHB1 mRNA and protein levels and relevance of this regulation were investigated in UACC-62 and SK-MEL-5 melanoma lines by RT-qPCR and western blot, luciferase reporter and genetic rescue experiments. Cell proliferation, cell-cycle analysis and caspase 3/7 assay were performed to investigate the potential action of miR-195 as chemosensitizer in melanoma cells treated with cisplatin and temozolomide. Results Analysis of the TCGA-RNAseq revealed a significant negative correlation (Pearson) between miR-195 and PHB1 expression. Moreover, RT-qPCR data showed that miR-195 is down-regulated while PHB1 is up-regulated in a collection of melanoma cells. We demonstrated that miR-195 regulates PHB1 directly by RT-qPCR and western blot in melanoma cells and luciferase assays. To establish PHB1 as a relevant target of miR-195, we conducted rescue experiments in which we showed that PHB1 transgenic expression could antagonize the suppressive effect miR-195 on the proliferation of melanoma cells. Finally, transfection experiments combined with drug treatments performed in the UACC-62 and SK-MEL-5 melanoma cells corroborated miR-195 as potential anti-proliferative agent, with potential impact in sensitization of melanoma cell death. Conclusions This study support the role of miR-195 as anti-proliferative miRNA via targeting of PHB1 in melanoma cells

    An Integrative Genomic and Transcriptomic Analysis Reveals Potential Targets Associated with Cell Proliferation in Uterine Leiomyomas

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    <div><p>Background</p><p>Uterine Leiomyomas (ULs) are the most common benign tumours affecting women of reproductive age. ULs represent a major problem in public health, as they are the main indication for hysterectomy. Approximately 40–50% of ULs have non-random cytogenetic abnormalities, and half of ULs may have copy number alterations (CNAs). Gene expression microarrays studies have demonstrated that cell proliferation genes act in response to growth factors and steroids. However, only a few genes mapping to CNAs regions were found to be associated with ULs.</p> <p>Methodology</p><p>We applied an integrative analysis using genomic and transcriptomic data to identify the pathways and molecular markers associated with ULs. Fifty-one fresh frozen specimens were evaluated by array CGH (JISTIC) and gene expression microarrays (SAM). The CONEXIC algorithm was applied to integrate the data.</p> <p>Principal Findings</p><p>The integrated analysis identified the top 30 significant genes (<i>P</i><0.01), which comprised genes associated with cancer, whereas the protein-protein interaction analysis indicated a strong association between FANCA and BRCA1. Functional <i>in silico</i> analysis revealed target molecules for drugs involved in cell proliferation, including FGFR1 and IGFBP5. Transcriptional and protein analyses showed that FGFR1 (<i>P</i> = 0.006 and <i>P</i><0.01, respectively) and IGFBP5 (<i>P</i> = 0.0002 and <i>P</i> = 0.006, respectively) were up-regulated in the tumours when compared with the adjacent normal myometrium.</p> <p>Conclusions</p><p>The integrative genomic and transcriptomic approach indicated that <i>FGFR1</i> and <i>IGFBP5</i> amplification, as well as the consequent up-regulation of the protein products, plays an important role in the aetiology of ULs and thus provides data for potential drug therapies development to target genes associated with cellular proliferation in ULs.</p> </div
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