IRAN AMORIM DA SILVA
Índice h a partir de 2011
10
Projetos de Pesquisa
Unidades Organizacionais
Instituto Central, Hospital das Clínicas, Faculdade de Medicina
LIM/55 - Laboratório de Urologia, Hospital das Clínicas, Faculdade de Medicina
LIM/55 - Laboratório de Urologia, Hospital das Clínicas, Faculdade de Medicina
2 resultados
Resultados de Busca
Agora exibindo 1 - 2 de 2
- The role of microRNAs 371 and 34a in androgen receptor control influencing prostate cancer behavior(2015) LEITE, Katia R. M.; MORAIS, Denis Reis; FLOREZ, Manuel Garcia; REIS, Sabrina T.; ISCAIFE, Alexandre; VIANA, Nayara; MOURA, Caio M.; SILVA, Iran A.; KATZ, Betina S.; PONTES JR., Jose; NESRALLAH, Adriano; SROUGI, MiguelBackground: The molecular mechanisms involved in androgen receptor (AR) signaling pathways are not completely understood, and deregulation of microRNAs (miRNAs) expression may play a role in prostate cancer (PC) development and progression. Methods: The expression levels of miRNA and AR were evaluated with quantitative real-time polymerase chain reaction using frozen tissue from the surgical specimens of 83 patients submitted to radical prostatectomy. The expression level of miRNAs was correlated with prognostic factors and biochemical recurrence during a follow-up period of 45 months. In vitro and in vivo experiments were performed to understand the effect of miRNAs over AR in the context of that seen in a PC model. Results: MiR-371 underexpression correlated with non-organ-confined (pT3) disease (P = 0.009). In vitro transfection of miR-371 reduced the levels of AR by 22% and 28% in LNCaP and PC3 cell lines, respectively, and in kallikrein 3, it was reduced by 51%. PC was induced in Balb/c mice using PC-3M-luc-C6 cells, and animals were treated with 3 local doses of miR-371. Tumor growth evaluated by in vivo imaging after luciferase injection was slower in animals treated with miR-371. To explore further the possible role of miRNAs in the AR pathway, LNCaP cell line was treated with 5 alpha-dihydrotestosterone and flutamide showing alteration in miRNAs expression, especially miR-34a, which was significantly underexpressed after treatment with high doses of 5 alpha-dihydrotestosterone. Conclusion: Our data support a role for miRNAs, especially miR-371 and miR-34a, in the complex disarrangement of AR signaling pathway and in the behavior of PC.
- Controlling RECK miR21 Promotes Tumor Cell Invasion and Is Related to Biochemical Recurrence in Prostate Cancer(2015) LEITE, Katia R. M.; REIS, Sabrina T.; VIANA, Nayara; MORAIS, Denis R.; MOURA, Caio M.; SILVA, Iran A.; PONTES JR., Jose; KATZ, Betina; SROUGI, MiguelThe search for biomarkers to characterize prostate cancer aggressiveness has been the objective for the majority of researchers involved with the most prevalent tumor in men. MiRNAs are important for the control of many cellular functions and their deregulation is involved with tumor development and progression. To find miRNAs differentially expressed in prostate cancer and their relation to prognostic factors and biochemical recurrence we studied 53 surgical specimens from men who underwent radical prostatectomy, through a microarray analysis using the microarray platform (GeneChip (R) miRNA Array - Affymetrix) with more than 46,000 probes and 847 mature human miRNAs and transcripts. We defined different as an expression level greater or less than 1.1 with p<0.05. The validation study using qRT-PCR had confirmed miR21 as overexpressed in tumor that have recurred with a risk of 2.5. Transfection of miR-21 using lipid based assay in DU145 cell line, showed decrease in expression of RECK resulting in increase in expression of MMP9. Invasion assay with Matrigel showed increase in tumor cell invasion after miR-21 transfection. We conclude that miR-21 overexpression is related to increased biochemical recurrence after surgical treatment of prostate cancer. And the negative control of RECK results in overexpression of MMP9 promotes increasing tumor cell invasion supporting miR-21 as an oncomiR related to aggressiveness in prostate cancer.