RESUMO
The acquisition of a castration-resistant prostate cancer phenotype by prostate cancer cells is the alteration that has the worst prognosis for patients. The aim of this study was to evaluate the role of the microRNAs-23b/-27b as well as the possible CCNG1 target gene in tissue samples from patients with localized prostate cancer that progressed to castration-resistant prostate cancer and in a castration-resistant prostate cancer cell line (PC-3). The microRNAs and target gene expression levels of the surgical specimens were analyzed by quantitative real-time polymerase chain reaction. The prostate cancer cell line, PC-3, was transfected with pre-miR-23b, pre-miR-27b, and their respective controls using Lipofectamine RNAiMAX and exposed or not to flutamide. After transfections, expression levels of both the microRNAs and the gene, CCNG1, were analyzed by quantitative real-time polymerase chain reaction. The apoptosis and cell cycle assays were performed on the mini MUSE cytometer. MicroRNAs-23b/-27b were underexpressed in surgical specimens of prostate cancer; however, their target gene, CCNG1, was overexpressed in 69% of the cases. After transfection with the microRNAs-23b/-27b and flutamide, we observed a reduction in gene expression compared with cells that were treated only with microRNAs or only with flutamide. In the apoptosis assay, we demonstrated cell sensitization following transfection with microRNAs-23b/-27b and potentiation when co-administered with flutamide. The number of cells in apoptosis was almost three times higher with the simultaneous treatments (miR + flutamide) compared with the control (p < 0.05). In the cell cycle assay, only flutamide treatment showed better results; a higher number of cells were found in the G0-G1 phase, and a lower percentage of cells completed the final phase of the cycle (p < 0.05). We conclude that microRNAs-23b/-27b are downexpressed in prostate cancer, and their target gene, CCNG1, is overexpressed. We postulated that microRNAs-23b/-27b sensitize the PC-3 cell line and that after the addition of flutamide in the apoptosis assay, we would observe synergism in the treatments between miR and flutamide. In the cell cycle assay, the use of flutamide was sufficient to decrease the number of cells in mitosis. Therefore, we postulate that microRNAs, along with other drugs, may become very useful therapeutic tools in the treatment of castration-resistant prostate cancer.
Assuntos
Apoptose/efeitos dos fármacos , Apoptose/genética , Ciclina G1/genética , Flutamida/metabolismo , MicroRNAs/genética , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Neoplasias de Próstata Resistentes à Castração/genética , Linhagem Celular Tumoral , Fase G1/efeitos dos fármacos , Fase G1/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Masculino , Pessoa de Meia-Idade , Mitose/efeitos dos fármacos , Mitose/genética , Próstata/efeitos dos fármacos , Fase de Repouso do Ciclo Celular/efeitos dos fármacos , Fase de Repouso do Ciclo Celular/genética , Transfecção/métodosRESUMO
INTRODUCTION: MicroRNAs (miRNA) are small non-coding RNAs that play an important role in the control of gene expression by inhibiting protein translation or promoting messenger RNA degradation. Today, miRNAs have been shown to be involved in various physiological and pathological cellular processes, including cancer, where they can act as oncogenes or tumor suppressor genes. Recently, lowered expression of miR-100, resulting in upregulation of FGFR3, has been correlated with low-grade, non-invasive bladder urothelial cancer, as an alternative oncogenesis pathway to the typical FGFR3 gene mutation. Our aim is to analyze the role of miR-100 in bladder cancer cell lines in controlling the expression of some of its possible target genes, including FGFR3 and its relationship with proliferation, apoptosis and DNA ploidy. METHODS: The bladder cancer cell lines RT4 and T24 were transfected with pre-miR 100, anti-miR 100 and their respective controls using a lipid-based formulation. After transfection mRNA and protein levels of its supposed target genes THAP2, BAZ2A, mTOR, SMARCA5 and FGFR3 were analyzed by quantitative real time polymerase chain reaction (qRT-PCR) and western blotting. Cell proliferation, apoptosis and DNA ploidy were analyzed by flow cytometry. For statistical analysis, a t-test was applied, p < 0.05 was considered significant. RESULTS: After miR-100 transfection, there was a significant reduction in the mRNA of mTOR (p = 0.006), SMARCA5 (p = 0.007) and BAZ2A (p = 0.029) in RT4, mTOR (p = 0.023) and SMARCA5 (p = 0.015) in T24. There was a reduction in the expression of all proteins, variable from 22.5% to 57.1% in both cell lines. In T24 miR-100 promoted an increase in cell proliferation and anti-miR 100 promoted apoptosis characterizing miR-100 as an oncomiR in this cell line representative of a high-grade urothelial carcinoma. CONCLUSION: miR-100 transfection reduces expression of BAZ2A, mTOR and SMARCA5 mRNA and protein in BC cell lines. miR-100 would be classified as an oncomiR in T24 cells representative of high grade urothelial carcinoma promoting increase in cell proliferation and reduction in apoptosis. The knowledge of miRNA role in tumors will allow their use as tumor markers and targets for new therapies.
RESUMO
Pathology training resources remain scarce in many parts of the world. With rapid economic development comes the need to educate new pathologists to meet the medical care demands. Our aim was to set up a cost-effective system for training and testing the diagnostic skills of pathologists. Pathologists in nine countries in Asia and South America were invited by the International Society of Urological Pathology (ISUP) to participate in a prostate pathology education course combining image-based tests with lectures and on-line tutorials. The tests and tutorials are available free of charge at the ISUP education website www.edu.isupweb.org . A total of 603 pathologists registered on the website. Of these, 224 completed pre- and post-lecture assessments (tests 1 and 2). Replies were classified as correct/acceptable, when a lesion was accurately classified into clinically relevant categories (benign, cancer, high-grade prostatic intraepithelial neoplasia, intraductal carcinoma of the prostate). The rate of correct/acceptable replies increased from 60.7 to 72.3% in Tests 1 and 2, respectively. In Test 1, pathologists from upper middle, lower middle, and low resource countries gave a correct/acceptable diagnosis in 65.8%, 61.0%, and 47.4%, respectively. Their results improved in Test 2 to 76.4%, 72.5%, and 62.8%, respectively. The greatest improvement in diagnostic ability was achieved in pathologists from the low resource group of countries. The use of web-based testing and training, combined with lectures, is an efficient method for improving diagnostic skills of pathologists in low to middle resource countries.
Assuntos
Carcinoma Intraductal não Infiltrante/patologia , Patologistas/educação , Próstata/patologia , Neoplasias da Próstata/patologia , Humanos , Internet , Masculino , Gradação de Tumores , Neoplasias da Próstata/diagnósticoRESUMO
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. .
Assuntos
Adulto , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Ósseas/secundário , MicroRNAs/metabolismo , Proteínas de Neoplasias/fisiologia , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Adenosina Trifosfatases/metabolismo , Moléculas de Adesão Celular/metabolismo , Proteínas Cromossômicas não Histona/metabolismo , Regulação Neoplásica da Expressão Gênica , Imuno-Histoquímica , /metabolismo , Metástase Linfática , MicroRNAs/genética , MicroRNAs/fisiologia , Proteínas de Neoplasias/metabolismo , Prognóstico , Neoplasias da Próstata/genética , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Proto-Oncogênicas c-myc/metabolismo , /metabolismo , Proteína do Retinoblastoma/metabolismoRESUMO
OBJECTIVE: 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. .