RESUMO
Prostate cancer (PCa) is a commonly diagnosed malignancy in men. The transcription factor p53, a well-known cancer suppressor, has been extensively analyzed in the progression of many tumor types, but its involvement in PCa remains not fully understood. Hence, this study aims to explore the possible molecular mechanism underlying p53 in the growth and metastasis of PCa. Based on bioinformatics analysis findings of GEPIA and starBase databases, p53 was demonstrated to be involved in the development of PCa by transcriptionally activating microRNA-519d-3p (miR-519d-3p) expression to suppress the expression of E2F transcription factor 1 (E2F1) and CD147. In order to verify this finding, clinically-obtained PCa tumor tissues were enrolled and commercially-purchased PCa cell lines were used to detect the cell viability, cycle, and apoptosis, as well as invasion and migration by CCK-8, flow cytometry, and Transwell assays respectively. The results of clinical tissue experiments and in vitro cell experiments showed that miR-519d-3p and p53 were poorly-expressed in PCa tissues and cell lines, while E2F1 was highly-expressed. Overexpression of miR-519d-3p led to inhibited PCa cell proliferation, invasion and migration, and p53 overexpression was found to promote miR-519d-3p expression to suppress the malignant characteristics of PCa cells, while the additional E2F1 overexpression restored the malignant traits. Moreover, ChIP analysis and dual-luciferase reporter assay confirmed the interactions among p53, miR-519d-3p, and E2F1. Mechanistically, it was found that p53 transcriptionally activated miR-519d-3p to suppress E2F1 expression. Finally, the in vitro results were further validated by in vivo experiments, which showed that miR-519d-3p prevents tumorigenesis and lymph node metastasis of PCa in nude mice via negatively regulation of E2F1 and CD147. Taken together, the findings uncover that the transcription factor p53 could upregulate miR-519d-3p expression to directly suppress the expression of E2F1, thus inhibiting PCa growth and metastasis. It highlights a novel therapeutic strategy against PCa based on the p53/miR-519d-3p/E2F1 regulatory pathway.
Assuntos
Fator de Transcrição E2F1 , MicroRNAs , Neoplasias da Próstata , Proteína Supressora de Tumor p53 , Animais , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Regulação para Baixo , Fator de Transcrição E2F1/genética , Fator de Transcrição E2F1/metabolismo , Humanos , Masculino , Camundongos , Camundongos Nus , MicroRNAs/genética , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Fatores de Transcrição/metabolismo , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismoRESUMO
Acute myeloid leukemia (AML) is a kind of malignant hematological disease with high mortality. Patients 5-year survival rate is less than 25% and that of elderly patients is lower than 10%. Although the standardized chemotherapy or hematopoetic stem cell transplantation can significantly improve the therapeutic efficacy for AML, but disease recurrence is still a difficult problem in most patients. Chemotherapy combined with immunotherapy has been regarded as the most promising treatment for AML in recent years, but immunotherapy is prone to immune escape, which has become an important factor affecting the therapeutic efficacy. Therefore, understanding the mechanism of immune escape of AML and taking corresponding measures in time to improve the therapeutic effect and reduce the recurrence of AML are of great significance. In this review, the important cells that cause immune escape, such as myeloid-derived suppressor cells (MDSC), natural killer cells (NK), and cell surface inhibitory receptor PD-1 (programmed death 1), which mediate immune escape of AML cells are summarized, so as to provide valuable reference for research to improve the effect of AML immunotherapy.
Assuntos
Transplante de Células-Tronco Hematopoéticas , Leucemia Mieloide Aguda , Idoso , Humanos , Imunoterapia , Células Matadoras Naturais , Transplante de Células-TroncoRESUMO
Many studies have recognized that circular RNAs (circRNAs) can be promising targets for renal cell carcinoma (RCC) by acting as competing endogenous RNAs for miRNAs. This study intends to uncover the implication of a novel circRNA, circ_000926 in RCC, and how it affects tumorigenesis. Microarray-based circRNA/gene expression profiling of RCC was used to identify differentially expressed circRNAs/genes in RCC and normal tissues. miRNAs targeting the screened circRNAs/genes were predicted online, followed by analyzing circ_000926 expression in RCC. The crosstalk among circ_000926, miRNA-411 (miR-411), and CDH2 was then validated. The expression of circ_000926, miR-411, and cadherin 2 (CDH2) was up-regulated or down-regulated in RCC cells to unearth their effects on the biological behaviors of RCC cells. circ_000926 was highly expressed in RCC tissues and cell lines, whereas CDH2 was verified to be a target of miR-411. As a competing endogenous RNA, circ_000926 could directly bind to miR-411 to up-regulate CDH2. Down-regulation of circ_000926 resulted in inhibited growth, migration, and invasion abilities of RCC cells, as well as suppressed epithelial-mesenchymal transition and tumor growth. However, the inhibition of miR-411 or elevation of CDH2 reversed the antitumor effects induced by silencing circ_000926. Down-regulation of circ_000926 exerts an inhibitory effect on RCC progression through miR-411-dependent CDH2 inhibition, highlighting a potential target for RCC treatment.
Assuntos
Antígenos CD/metabolismo , Biomarcadores Tumorais/metabolismo , Caderinas/metabolismo , Carcinoma de Células Renais/patologia , Neoplasias Renais/patologia , MicroRNAs/genética , RNA Circular/genética , Animais , Antígenos CD/genética , Apoptose , Biomarcadores Tumorais/genética , Caderinas/genética , Carcinoma de Células Renais/genética , Carcinoma de Células Renais/metabolismo , Adesão Celular , Movimento Celular , Proliferação de Células , Progressão da Doença , Transição Epitelial-Mesenquimal , Feminino , Seguimentos , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Renais/genética , Neoplasias Renais/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Prognóstico , Taxa de Sobrevida , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
The enhancer of zeste 2 polycomb repressive complex 2 subunit (EZH2) gene has been recognized to be a protooncogene and to be linked to human malignancies. However, the additional functions of EZH2 in renal cell carcinoma (RCC) are not completely understood. In the present study, a possible role of EZH2 in RCC was identified. EZH2 was demonstrated to promote the cell proliferation and invasion potential of 769P cells, and inhibition of EZH2 was demonstrated to prevent these two processes in 786O cells. Mechanically, EZH2 was demonstrated to increase the phosphorylation of signal transducer and activator of transcription 3 (STAT3) and upregulate 72 kDa type IV collagenase (MMP2) expression. When cells were treated with small interfering RNA targeting STAT3 or Stattic, a specific inhibitor of STAT3, the invasive ability of the cells was decreased and downregulation of MMP2 was observed. Based on these results, in the present study it was hypothesized that EZH2 may serve a critical role in the progression of RCC. Its ability to facilitate invasion makes EZH2 a promising target for the management of advanced RCC.
