NAYARA IZABEL VIANA MOURA
Projetos de Pesquisa
Unidades Organizacionais
LIM/55 - Laboratório de Urologia, Hospital das Clínicas, Faculdade de Medicina
5 resultados
Resultados de Busca
Agora exibindo 1 - 5 de 5
- Gene expression profile of renal cell carcinomas after neoadjuvant treatment with sunitinib: new pathways revealed(2017) DZIK, Carlos; REIS, Sabrina T.; VIANA, Nayara I.; BRITO, Glauber; PALOPPI, Isis; NAHAS, Willian; SROUGI, Miguel; LEITE, Katia R. M.Background: In renal cell carcinoma (RCC) of the clear cell type, inactivity of the VHL gene induces overexpression of HIF1 alpha and its targets, the tyrosine kinase receptors, promoting RCC development and progression. The discovery of tyrosine kinase inhibitors (TKIs) changed the treatment of these tumors. Other molecular pathways involved in the TKI mechanisms of action have not been described in the literature. The aim of our study was to elucidate alternative mechanisms of action of sunitinib in tumor tissue after neoadjuvant treatment of RCC. Methods: The gene expression profile was accessed using microarray (Affymetrix Human Genome U133 Plus 2.0 platform) and frozen RCC tissues collected from 5 patients with locally advanced non-metastatic tumors who underwent nephrectomy after being treated with 2 cycles of neoadjuvant sunitinib. The results were compared with matched controls comprising 6 patients with no neoadjuvant intervention. Results: There was underexpression of the majority of genes after sunitinib treatment. The lower expression levels of IGFBP1, CCL20, CXCL6 and FGB were confirmed by qRT-PCR in all cases. The downregulation of gene expression leads us to search for methylation as a mechanism of action of the TKI. IGFBP1 was shown to be methylated by methylation-sensitive high-resolution melting technique. Conclusions: The ultimate genetic effects of sunitinib may explain its actions as an antitumor drug that apparently suppresses the expression of important genes related to cell survival, adhesion, invasion and immunomodulation. The methylation of gene promoters was shown to be part of the mechanism of action of this class of drugs.
- MicroRNAs 143 and 145 may be involved in benign prostatic hyperplasia pathogenesis through regulation of target genes and proteins(2014) VIANA, Nayara I.; REIS, Sabrina T.; DIP, Nelson G.; MORAIS, Denis R.; MOURA, Caio M.; SILVA, Iran A.; KATZ, Betina; SROUGI, Miguel; LEITE, Katia R. M.; ANTUNES, Alberto A.Objectives: The aim of this study was to analyze the roles of miR-143 and miR-145, as well as the gene and protein expression of their targets (KRAS, ERK5, MAP3K3, and MAP4K4) in the pathogenesis of benign prostatic hyperplasia (BPH). Methods: We analyzed the specimens of 44 patients diagnosed with BPH who underwent surgical treatment. The control group consisted of prostate samples from 2 young patients who were organ donors. miRNAs and their target genes were assessed using real-time polymerase chain reaction (qRT-PCR), and protein levels were assessed by Western blotting. Results: miR-143 and miR-145 were overexpressed in, respectively, 62.5% and 73.8% of the cases. The ERK5 and MAP4K4 genes were underexpressed respectively in 59.4% and 100% of the BPH samples, whereas KRAS and MAP3K3 were overexpressed respectively in 79.4% and 61.5% of the samples. Increased protein expression was found for both KRAS (4,312.2 luminance/area) and MAP3K3 (7,461.7 luminance/area), while the ERK5 protein was more abundant in the samples from patients with prostate larger than 60 grams (p = 0.019). Conclusions: The overexpression of miR-143 and miR-145 in BPH samples suggests an association with the pathogenesis of the disease; additionally, the latter miRNA may act through the inhibition of MAP4K4. KRAS and MAP3K3 overexpression may also be associated with BPH pathogenesis. Further analyses are necessary to confirm these results.
- The role of single nucleotide polymorphisms of miRNAs 100 and 146a as prognostic factors for prostate cancer(2021) CAMARGO, Juliana Alves de; LOPES, Renan Eboli; FERREIRA, Gabriel Fernandes Dias; VIANA, Nayara Izabel; GUIMARAES, Vanessa; LEITE, Katia Ramos Moreira; NAHAS, William C.; SROUGI, Miguel; ANTUNES, Alberto A.; REIS, Sabrina T.Introduction: Prostate cancer has a high incidence in men and is the second cause of cancer death among americans male. microRNA (miR) is becoming a potential new prognostic factor for prostate cancer. Single nucleotide polymorphisms (SNPs) are common polymorphisms, characterized by a single exchange of nitrogen based in the DNA. This polymorphism is present in the miRs, altering their function. Objective: To evaluate the role of SNP rs1834306 of miR100 and rs2910164 of miR146a in the development and prognosis of prostate cancer. Methods: One hundred patients diagnosed with prostate cancer and 68 controls were selected. The identification of SNP was rated by quantitative polymerase chain reaction from blood samples, and the analysis was performed within the presence of SNP and the prognostic variables. Results: In the SNP rs1834306 (miR100), a smaller presence of the polymorphic homozygous genotype was identified in patients with PSA >10 ng/mL, (P=0.03); when evaluating only the presence of the polymorphic allele G (P=0.09) it was compared to the presence of the wild type allele A. Among the patients with prostate cancer, SNP rs2910164 (miR146A), the polymorphic allele was more frequent in patients with a Gleason score > 7 than in patients with a Gleason score <7, (P=0.043). In patients with prostate cancer, miR100 was overexpressed in those with pT3 staging compared to pT2 and among those who had biochemical recurrence (P = 0.004 and P = 0.011, respectively). Conclusions: SNP of miR146a acts as a poor prognostic factor (Gleason > 7), and the SNP of miR100 is linked to better prognostic data (PSA <10). MiR100 was overexpressed in prostate cancer with worse prognostic factors.
- Correlation between chromosome 9p21 locus deletion and prognosis in clinically localized prostate cancer(2017) BARROS, Erika Aparecida Felix de; PONTES-JUNIOR, Jose; REIS, Sabrina Thalita; LIMA, Amanda Eunice Ramos; SOUZA, Isida C.; SALGUEIRO, Jose Lucas; FONTES, Douglas; DELLE, Humberto; COELHO, Rafael Ferreira; VIANA, Nayara Izabel; LEITE, Katia Ramos Moreira; NAHAS, William C.; SROUGI, MiguelBackground: Some studies have reported that deletions at chromosome arm 9p occur frequently and represent a critical step in carcinogenesis of some neoplasms. Our aim was to evaluate the deletion of locus 9p21 and chromosomes 3, 7 and 17 in localized prostate cancer (PC) and correlate these alterations with prognostic factors and biochemical recurrence after surgery. Methods: We retrospectively evaluated surgical specimens from 111 patients with localized PC who underwent radical prostatectomy. Biochemical recurrence was defined as a prostate-specific antigen (PSA) >0.2 ng/mL and the mean postoperative follow-up was 123 months. The deletions were evaluated using fluorescence in situ hybridization with centromeric and locus-specific probes in a tissue microarray containing 2 samples from each patient. We correlated the occurrence of any deletion with pathological stage, Gleason score, ISUP grade group, PSA and biochemical recurrence. Results: We observed a loss of any probe in only 8 patients (7.2%). The most common deletion was the loss of locus 9p21, which occurred in 6.4% of cases. Deletions of chromosomes 3, 7 and 17 were observed in 2.3%, 1.2% and 1.8% patients, respectively. There was no correlation between chromosome loss and Gleason score, ISUP, PSA or stage. Biochemical recurrence occurred in 83% cases involving 9p21 deletions. Loss of 9p21 locus was significantly associated with time to recurrence (p = 0.038). Conclusions: We found low rates of deletion in chromosomes 3, 7 and 17 and 9p21 locus. We observed that 9p21 locus deletion was associated with worse prognosis in localized PC treated by radical prostatectomy.
- Expression profile of standard and variants forms of CD44 related to prostate cancer behavior(2015) MOURA, Caio M.; PONTES JR., Jose; REIS, Sabrina T.; VIANA, Nayara I.; MORAIS, Denis R.; DIP, Nelson; KATZ, Betina; SROUGI, Miguel; LEITE, Katia R. M.CD44 is a transmembrane glycoprotein and is regarded as a potential marker in various tumors. The aim of our study was to analyze the expression of the standard form of CD44 (CD44s) and its isoforms in localized prostate cancer (PCa), and to correlate these data with the classical prognostic factors and biochemical recurrence. Ninety-four surgical specimens were analyzed in this study. The expression levels of CD44s and all its 9 variants were analyzed by quantitative real time PCR (qRT-PCR). The control group consisted of 14 specimens from patients with benign prostatic hyperplasia. We correlated all the expression profiles with biochemical recurrence, as defined by a PSA > 0.4 ng/mL in a mean follow-up period of 53.3 months. In PCa, CD44s was underexpressed and all the other isoforms were overexpressed. The mean expression level of most variants was higher in patients who had not recurred, and a higher expression of CD44v2 independently correlated with a better recurrence-free survival rate (p=0.045). This variant was also underexpressed in metastatic PCa cell lines. There was no correlation between the expression levels of any of the CD44 isoforms and the classical prognostic factors. We here demonstrated that PCa cases are characterized by a change in the expression of CD44, with a loss of CD44s and an overexpression of all the other CD44 variants. However, during cancer progression we found a loss of expression of all CD44 variants, and a correlation between higher expression of CD44v2 and a better recurrence-free survival rate. The understanding of the CD44 expression patterns in PCa could contribute to its use as a new prognostic marker.