BETINA STIFELMAN KATZ
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
- 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.
conferenceObject The expression levels of microRNAs that have the androgen receptor in localized prostate cancer as a target(2014) LEITE, Katia Ramos Moreira; FLOREZ, Manuel Garcia; REIS, Sabrina Thalita; VIANA, Nayara; KATZ, Betina S.; DIP, Nelson; SILVA, Iran Amorin; PONTES JR., Jose; SROUGI, Miguel- 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.
- 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.
- Perineural invasion detection in prostate biopsy is related to recurrence-free survival in patients submitted to radical prostatectomy(2013) KATZ, Betina; SROUGI, Miguel; DALL'OGLIO, Marcos; NESRALLAH, Adrian J.; SANT'ANNA, Alexandre C.; PONTES JR., Jose; ANTUNES, Alberto A.; REIS, Sabritia T.; VIANA, Nayara; SANUDO, Adriana; CAMARA-LOPES, Luiz H.; LEITE, Katia R. M.Objective: Perineural invasion (PNI) is detected in almost 20% of prostate biopsies and has been related to worse prognostic factors in radical prostatectomy (RP) specimens and lower disease-free survival rates. The aim of this study was to evaluate the importance of PNI during periods of extended prostate biopsies and to determine the value of this preoperative parameter as a predictor of pathologic findings in surgical specimens and in biochemical recurrence. Materials and methods: Between 2001 and 2009, 599 prostate biopsies and their respective RP specimens were examined in our laboratory. The RP specimens were always examined completely. The mean age of the patients was 61 years, and the mean PSA was 6.4 ng/mL. The mean and median number of biopsy cores obtained was 14.4 and 14, respectively. PNI was identified in 105 biopsies (17.5%). We studied the ability of PNI in prostate biopsies to determine the tumor stage in surgical specimens and the relationship of PNI with biochemical recurrence during a mean follow-up time of 51.4 months. Results: The presence of PNI in prostate biopsies was observed in older patients (63 vs. 61 years old, P = 0.008). All of the prognostic factors determined for the RP specimens were significantly worse in patients with PNI compared with those without PNI. PNI was strongly associated with a higher pathologic stage (87% specificity, 40% sensitivity, odds ratio 4.8). Stage pT3 prostatic cancer was determined in 46 (43.8%) of 105 patients with PNI on biopsy compared to 69 (14%) of 494 patients without PNI (P = 0.01). Fifty-six (19.6%) patients had a biochemical recurrence, and PNI correlated significantly with PSA recurrence. A Kaplan-Meier analysis revealed a significant difference in recurrence-free survival between patients with and without PNI (45% vs. 53%, respectively, P = 0.021, log-rank test = 0.19). Conclusion: PNI is an important morphologic preoperative predictor of the pathologic stage as well as biochemical recurrence and must always be mentioned when adenocarcinoma is diagnosed on prostate biopsies.