RESUMO
OBJECTIVE: MiRNAs are small, noncoding RNA molecules that serve as important regulators of cancer-related processes. Abnormal expression of miR-577 has been found in several tumors. However, the expression pattern and biological function of miR-577 in progression of papillary thyroid cancer (PTC) remain unknown. This study is aimed to determine its expression pattern and explore the function underlying the mechanism of miR-577 in PTC. PATIENTS AND METHODS: Using quantitative RT-PCR, we detected miR-577 expression in PTC cell lines and primary tumor tissues. MTT assay and colony formation were performed to measure the viabilities of tumor cells. Transwell invasion and migration assays were used to test the invasion and migration of PTC cells transfected with miR-577 mimic. TargetScan, miRanda and PicTar were used to analyze whether sphingosine kinase 2 (SphK2) was a potential target gene. Next, the direct target gene of miR-577 was also identified by luciferase reporter assays and Western blot analysis. RESULTS: The results showed that miR-577 was significantly downregulated in PTC tissues and cell lines. The up-regulation of miR-577 inhibited the proliferation, migration and invasion of PTC cells in vitro. Furthermore, bioinformatics analysis indicated that SphK2 was a putative target of miR-577. A luciferase reporter assay further confirmed that SphK2 was a direct target of miR-577. The results of Western blot indicated that the expression level of miR-577 was negatively correlated with the expression level of SphK2 in PTC tissues. In addition, knockdown of SphK2 significantly suppressed PTC cells proliferation, migration and invasion. CONCLUSIONS: Our findings indicate that miR-577 is a potential tumor suppressor in PTC by targeting SphK2, and may be a potential therapeutic target in PTC.
Assuntos
Carcinoma Papilar/genética , Carcinoma Papilar/patologia , Movimento Celular , Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , Invasividade Neoplásica/genética , Fosfotransferases (Aceptor do Grupo Álcool)/genética , Neoplasias da Glândula Tireoide/genética , Neoplasias da Glândula Tireoide/patologia , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Células Cultivadas , Regulação para Baixo , Feminino , Técnicas de Silenciamento de Genes , Humanos , Fosfotransferases (Aceptor do Grupo Álcool)/biossíntese , Câncer Papilífero da Tireoide , Regulação para CimaRESUMO
OBJECTIVE: The objective of this study was to examine the correlation between the presence of primary iris-ciliary cysts and the intraocular pressure. PATIENTS AND METHODS: Sixty patients with short-sightedness undergoing routine examination for laser vision correction in our hospital in 2003 were enrolled. Patients with known high intraocular pressure and risk of glaucoma were excluded from the study. A total of 119 eyes were examined by the Ultrasound Biomicroscope (UBM), and the presence of the primary iris-ciliary cysts was confirmed. Intraocular pressure was measured by using a blowing tonometer for each eye in triplicate. Through Pentacam correction of intraocular pressure using the Ehlers formula, the influence of the thickness of central cornea on intraocular pressure was excluded. RESULTS: Among all participants, 62 eyes (52.1%) were with high myopia, 57 eyes (47.9%) with low and moderate myopia, 27 eyes (22.7%) with single cyst, 20 eyes (16.8%) with multiple cysts, and 72 eyes (60.5%) were free from cysts. Moreover, the intraocular pressure was found within the normal range in 72 eyes (60.5%), and abnormally high in 47 eyes (39.5%). CONCLUSIONS: Our results showed that the presence of primary iris-ciliary cysts and the intraocular pressure were positively correlated, with a correlation coefficient of 0.235 (p = 0.01). These findings may prove useful for prediction and screening of high intraocular pressure.