KATIA RAMOS MOREIRA LEITE
Projetos de Pesquisa
Unidades Organizacionais
Departamento de Cirurgia, Faculdade de Medicina - Docente
LIM/55 - Laboratório de Urologia, Hospital das Clínicas, Faculdade de Medicina - Líder
LIM/26 - Laboratório de Pesquisa em Cirurgia Experimental, Hospital das Clínicas, Faculdade de Medicina
LIM/55 - Laboratório de Urologia, Hospital das Clínicas, Faculdade de Medicina - Líder
LIM/26 - Laboratório de Pesquisa em Cirurgia Experimental, Hospital das Clínicas, Faculdade de Medicina
7 resultados
Resultados de Busca
Agora exibindo 1 - 7 de 7
- Curcumin, but not Prima-1, decreased tumor cell proliferation in the syngeneic murine orthotopic bladder tumor model(2011) WATANABE, Fabio T.; CHADE, Daher C.; REIS, Sabrina T.; PIANTINO, Camila; OGLIO, Marcos Francisco Dall'; SROUGI, Miguel; LEITE, Katia R. M.OBJECTIVE: Cigarette smoking is the main risk factor for bladder cancer development. Among the mediators of this effect of smoking is nuclear factor-kappa B. Curcumin suppresses cellular transformation by downregulating the activity of nuclear factor-kappa B. Prima-1 is a compound that induces apoptosis in human tumor cells, restoring the function of mutant p53. Our study aimed to evaluate the effects of curcumin and prima-1 in an animal model of bladder cancer. METHODS: Tumor implantation was achieved in six-to eight-week-old female C57BL/6 mice by introducing MB49 bladder cancer cells into the bladder. Intravesical treatment with curcumin and Prima-1 was performed on days 2, 6, 10, and 14. On day 15, the animals were sacrificed. Immunohistochemistry was used to determine the expression of cyclin D1, Cox-2, and p21. Cell proliferation was examined using PCNA. RESULTS: Animals treated with curcumin exhibited a higher degree of necrosis than animals in other groups. Immunohistochemistry showed reduced expression of cyclin D1 in the curcumin-treated group. All of the cells in mice treated with curcumin were p21 positive, suggesting that the p53 pathway is induced by this compound. Prima-1 did not induce any change in tumor size, necrosis, cell proliferation, or the expression of proteins related to the p53 pathway in this animal model. CONCLUSION: Curcumin showed activity in this animal bladder cancer model and probably acted via the regulation of nuclear factor-kappa B and p53. Therefore, curcumin is a good choice for the use in clinical trials to treat superficial bladder cancer as an alternative to bacillus Calmette-Guerin. In contrast, Prima-1 does not seem to have an effect on bladder cancer.
- Detecting and grading prostate cancer in radical prostatectomy specimens through deep learning techniques(2021) MELO, Petronio Augusto de Souza; ESTIVALLET, Carmen Liane Neubarth; SROUGI, Miguel; NAHAS, William Carlos; LEITE, Katia Ramos MoreiraOBJECTIVES: This study aims to evaluate the ability of deep learning algorithms to detect and grade prostate cancer (PCa) in radical prostatectomy specimens. METHODS: We selected 12 whole-slide images of radical prostatectomy specimens. These images were divided into patches, and then, analyzed and annotated. The annotated areas were categorized as follows: stroma, normal glands, and Gleason patterns 3, 4, and 5. Two analyses were performed: i) a categorical image classification method that labels each image as benign or as Gleason 3, Gleason 4, or Gleason 5, and ii) a scanning method in which distinct areas representative of benign and different Gleason patterns are delineated and labeled separately by a pathologist. The Inception v3 Convolutional Neural Network architecture was used in categorical model training, and a Mask Region-based Convolutional Neural Network was used to train the scanning method. After training, we selected three new whole-slide images that were not used during the training to evaluate the model as our test dataset. The analysis results of the images using deep learning algorithms were compared with those obtained by the pathologists. RESULTS: In the categorical classification method, the trained model obtained a validation accuracy of 94.1% during training; however, the concordance with our expert uropathologists in the test dataset was only 44%. With the image-scanning method, our model demonstrated a validation accuracy of 91.2%. When the test images were used, the concordance between the deep learning method and uropathologists was 89%. CONCLUSION: Deep learning algorithms have a high potential for use in the diagnosis and grading of PCa. Scanning methods are likely to be superior to simple classification methods.
- Telomere Attrition and p53 Response 1 (TAPR1): a new player in cancer biology?(2021) SANTOS, Gabriel Arantes dos; REIS, Sabrina T.; LEITE, Katia Ramos Moreira; SROUGI, Miguel
- Prima-1 induces apoptosis in bladder cancer cell lines by activating p53(2013) PIANTINO, Camila B.; REIS, Sabrina T.; VIANA, Nayara I.; SILVA, Iran A.; MORAIS, Denis R.; ANTUNES, Alberto A.; DIP, Nelson; SROUGI, Miguel; LEITE, Katia R.OBJECTIVES: Bladder cancer represents 3% of all carcinomas in the Brazilian population and ranks second in incidence among urological tumors, after prostate cancer. The loss of p53 function is the main genetic alteration related to the development of high-grade muscle-invasive disease. Prima-1 is a small molecule that restores tumor suppressor function to mutant p53 and induces cancer cell death in various cancer types. Our aim was to investigate the ability of Prima-1 to induce apoptosis after DNA damage in bladder cancer cell lines. METHOD: The therapeutic effect of Prima-1 was studied in two bladder cancer cell lines: T24, which is characterized by a p53 mutation, and RT4, which is the wild-type for the p53 gene. Morphological features of apoptosis induced by p53, including mitochondrial membrane potential changes and the expression of thirteen genes involved in apoptosis, were assessed by microscopic observation and quantitative real-time PCR (qRT-PCR). RESULTS: Prima-1 was able to reactivate p53 function in the T24 (p53 mt) bladder cancer cell line and promote apoptosis via the induction of Bax and Puma expression, activation of the caspase cascade and disruption of the mitochondrial membrane in a BAK-independent manner. CONCLUSION: Prima-1 is able to restore the transcriptional activity of p53. Experimental studies in vivo may be conducted to test this molecule as a new therapeutic agent for urothelial carcinomas of the bladder, which characteristically harbor p53 mutations.
- Tgf-beta 1 expression as a biomarker of poor prognosis in prostate cancer(2011) REIS, Sabrina Thalita dos; PONTES-JUNIOR, Jose; ANTUNES, Alberto Azoubel; SOUSA-CANAVEZ, Juliana Moreira de; ABE, Daniel Kanda; CRUZ, Jose Arnaldo Shiomi da; DALL'OGLIO, Marcos Francisco; CRIPPA, Alexandre; PASSEROTTI, Carlo Camargo; RIBEIRO-FILHO, Leopoldo A.; VIANA, Nayara Izabel; SROUGI, Miguel; LEITE, Katia Ramos MoreiraOBJECTIVE: To evaluate the correlation between transforming growth factor beta (TGF-beta 1) expression and prognosis in prostate cancer. PATIENTS AND METHODS: TGF-beta 1 expression levels were analyzed using the quantitative real-time polymerase chain reaction to amplify RNA that had been isolated from fresh-frozen malignant and benign tissue specimens collected from 89 patients who had clinically localized prostate cancer and had been treated with radical prostatectomy. The control group consisted of 11 patients with benign prostate hyperplasia. The expression levels of TGF-beta 1 were compared between the groups in terms of Gleason scores, pathological staging, and prostate-specific antigen serum levels. RESULTS: In the majority of the tumor samples, TGF-beta 1 was underexpressed 67.0% of PCa patients. The same expression pattern was identified in benign tissues of patients with prostate cancer. Although most cases exhibited underexpression of TGF-beta 1, a higher expression level was found in patients with Gleason scores >= 7 when compared to patients with Gleason scores <7 (p = 0.002). Among the 26 cases of TGF-beta 1 overexpression, 92.3% had poor prognostic features. CONCLUSIONS: TGF-beta 1 was underexpressed in prostate cancers; however, higher expression was observed in tumors with higher Gleason scores, which suggests that TGF-beta 1 expression may be a useful prognostic marker for prostate cancer. Further studies of clinical specimens are needed to clarify the role of TGF-beta 1 in prostate carcinogenesis.
- The role of micro RNAs let7c, 100 and 218 expression and their target RAS, C-MYC, BUB1, RB, SMARCA5, LAMB3 and Ki-67 in prostate cancer(2013) REIS, Sabrina T.; TIMOSZCZUK, Luciana S.; PONTES-JUNIOR, Jose; VIANA, Nayara; SILVA, Iran A.; DIP, Nelson; SROUGI, Miguel; LEITE, Katia R. M.OBJECTIVE: The aim of this study is to verify the expression of proteins that are controlled by miR-let7c, 100 and 218 using immunohistochemistry in tissue microarray representative of localized and metastasized the lymph nodes and bone prostate cancer. METHODS: To verify the expression of proteins that are controlled by miR-let7c (C-MYC, BUB1, RAS) 100 (SMARCA5, RB) and 218 (LAMB3) and cell proliferation (Ki-67) we used immunohistochemistry and computerized image system ImageJ MacBiophotonics in three tissue microarrays representative of localized prostate cancer and lymph node and bone metastases. miRNA expression was evaluated by qRT-PCR using 60 paraffin blocks to construct the tissue microarray representative of localized disease. RESULTS: RAS expression was increased in localized prostate cancer and bone metastases compared to the lymph nodes (p = 0.017). RB showed an increase in expression from localized prostate cancer to lymph node and bone metastasis (p = 0.036). LAMB3 was highly expressed in localized and lymph node metastases (p<0.001). Cell proliferation evaluated by Ki-67 showed an increase from localized prostate cancer to metastases (p<0.001). We did not found any relationship between C-MYC (p = 0.253), BUB1 (p = 0.649) and SMARCA5 (p = 0.315) protein expression with prognosis or tumor behavior. CONCLUSION: We found that the expression of RAS, RB, LAMB3 and Ki-67 changed in the different stages of prostate cancer. Furthermore, we confirmed the overexpression of the miRNAs let7c, 100 and 218 in localized prostate cancer but failed to show the control of protein expression by the putative controller miRNAs using immunohistochemistry.
- MicroRNA 100: a context dependent miRNA in prostate cancer(2013) LEITE, Katia R. M.; MORAIS, Denis R.; REIS, Sabrina T.; VIANA, Nayara; MOURA, Caio; FLOREZ, Manuel Garcia; SILVA, Iran A.; DIP, Nelson; SROUGI, MiguelOBJECTIVE: MicroRNAs are noncoding RNA molecules involved in the development and progression of tumors. We have found that miRNA-100 is underexpressed in metastatic prostate cancer compared to localized disease. Conversely higher levels of miR-100 are related to biochemical recurrence after surgery. This suggests that miR-100 may be a context-dependent miRNA, acting as oncogene or tumor suppressor miRNA. Our aim is to demonstrate the role of miR-100 in the control of predicted target genes in prostate cancer cell lines. METHODS: Cell lines DU145 and PC3 were transfected with miR-100, antimiR-100 and after 24 h and 48 h of exposure, qRT-PCR and western blot were performed for mTOR, FGFR3, THAP2, SMARCA5 and BAZ2A. RESULTS: There was reduction in mTOR (p = 0.025), THAP2 (p = 0.038), SMARCA5 (p = 0.001) and BAZ2A (p = 0.006) mRNA expression in DU145 cells after exposure to miR-100. In PC3 cells, mTOR expression was decreased by miR-100 (p = 0.01). There was a reduction in the expression levels of proteins encoded by studied genes, ranging from 34% to 69%. CONCLUSIONS: We demonstrate that miR-100 is a context-dependent miRNA controlling BAZ2, mTOR, FGFR3, SMARCA5 and THAP2 that might be involved in PC progression. The elucidation of the roles of miRNAs in tumors is important because they can be used as therapeutic targets in the future.