RESUMO
It has been shown that microRNA-215 (miR-215) is dysregulated in several human malignancies, and this correlates with tumor progression. However, its expression and function in pancreatic cancer is still unclear. The aim of this study was to explore the effects of miR-215 on pancreatic cancer formation and progression. Using quantitative RT-PCR, we detected miR-215 expression in pancreatic cancer cell lines and primary tumor tissues. The association of miR-215 expression with clinicopathological factors and prognosis was also analyzed. We then observed the effects of miR-215 on the biological behavior of pancreatic cancer cells. Lastly, the potential regulatory function of miR-215 on ZEB2 expression was investigated. miR-215 expression levels were significantly downregulated in pancreatic cancer samples and cell lines. Decreased miR-215 expression was significantly associated with large tumor size, advanced TNM stage, lymph node metastasis, vessel invasion, and lower overall survival. Multivariate regression analysis corroborated that downregulation of miR-215 was an independent unfavorable prognostic factor. Overexpression of miR-215 inhibited pancreatic cancer cell proliferation, invasion, and migration; promoted cell apoptosis in vitro; and suppressed tumorigenicity in vivo. Further, ZEB2 was confirmed as a direct target of miR-215 by using a luciferase reporter assay. These findings indicate that miR-215 may act as a tumor suppressor in pancreatic cancer cells, and could serve as a novel therapeutic target for miR-based therapy.
Assuntos
Genes Supressores de Tumor , Proteínas de Homeodomínio/genética , MicroRNAs/genética , Neoplasias Pancreáticas/genética , Interferência de RNA , Proteínas Repressoras/genética , Regiões 3' não Traduzidas , Adulto , Idoso , Animais , Apoptose/genética , Sequência de Bases , Sítios de Ligação , Linhagem Celular Tumoral , Proliferação de Células , Modelos Animais de Doenças , Regulação para Baixo , Feminino , Regulação Neoplásica da Expressão Gênica , Xenoenxertos , Proteínas de Homeodomínio/química , Humanos , Masculino , Camundongos , MicroRNAs/química , Pessoa de Meia-Idade , Gradação de Tumores , Metástase Neoplásica , Estadiamento de Neoplasias , Neoplasias Pancreáticas/mortalidade , Neoplasias Pancreáticas/patologia , Prognóstico , RNA Mensageiro/química , RNA Mensageiro/genética , Proteínas Repressoras/química , Carga Tumoral , Homeobox 2 de Ligação a E-box com Dedos de ZincoRESUMO
Forkhead box protein O1 (FOXO1) is an important transcriptional regulator of cell proliferation, and is considered essential for tumor growth and progression. However, the function of FOXO1 in human cervical cancer remains unclear. In this study, we investigated the role of FOXO1 in cervical cancer. Our results showed that FOXO1 expression was lower in cervical cancer than in cervical intraepithelial neoplasia and normal cervix by immunohistochemical analysis (P < 0.05). The level of FOXO1 in high-grade lesions was significantly lower than in low-grade lesion (P < 0.05), indicating that deficient expression of FOXO1 is involved in tumor progression and significantly associated with late-stage tumors (P < 0.05), which was further supported by clinicopathological, real-time polymerase chain reaction, and Western blotting analysis. Moreover, we confirmed that the overexpression of FOXO1 remarkably repressed cell growth and blocked cell proliferation, accompanied by cell-cycle arrest in the G2/M phase and upregulation of caspases-3 and -9 gene expression. Collectively, our data suggest that FOXO1 plays a vital role in inhibiting cervical cancer development by inducing cell-cycle arrest and apoptosis. FOXO1 expression is a favorable prognostic factor for human cervical cancer.
Assuntos
Ciclo Celular/genética , Fatores de Transcrição Forkhead/biossíntese , Genes Supressores de Tumor , Neoplasias do Colo do Útero/genética , Apoptose/genética , Linhagem Celular Tumoral , Proliferação de Células/genética , Feminino , Proteína Forkhead Box O1 , Fatores de Transcrição Forkhead/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias do Colo do Útero/patologiaRESUMO
Saccharum spontaneum is the most variable wild relative of sugarcane with potential for use in sugarcane improvement programs. In order to help preserve and exploit this species, 152 accessions from eight major geographical regions in China, including Hainan, Guangdong, Guangxi, Yunnan, Sichuan, Guizhou, Fujian, and Jiangxi provinces, were investigated by analyzing 20 simple sequence repeats (SSRs), including 11 genomic SSRs (gSSRs) and nine SSRs developed from expressed sequence tags (EST-SSRs). A total of 454 alleles were generated by the 20 SSRs, with 295 and 159 alleles detected by gSSRs and EST-SSRs respectively. The Mantel test showed significant correlation between genetic matrixes among the studied accessions revealed by gSSRs versus EST-SSRs, although the average polymorphism of EST-SSRs (17.7) was much lower than that of gSSRs (26.8). Among the eight provinces, collections from Guizhou were the most diverse and those from Guangdong were the most distinct. Clustering analysis and principal component analysis accordantly classified the accessions into four groups, which were "Southwest group", "Hainan group", "Guangdong group", and "Guangxi group", based on the geographical origin of the major accessions in each group, demonstrating that geographical factors play an important role in the pattern of genetic structure of Chinese S. spontaneum. As two (Guizhou and Yunnan) of the three provinces with highest genetic diversity are located in southwest China, we concluded that southwest China is the region with the highest genetic diversity of S. spontaneum.