Downregulation of Rap1GAP Expression Activates the TGF-ß/Smad3 Pathway to Inhibit the Expression of Sodium/Iodine Transporter in Papillary Thyroid Carcinoma Cells.

OBJECTIVE: Rap1GAP is considered a tumor suppressor gene, but its regulatory mechanism in papillary thyroid cancer (PTC) has not been clearly elucidated. The aim of this study was to explore whether the regulation between Rap1GAP and sodium/iodine transporter (NIS) in tumorigenesis of PTC is mediated by TGF-ß1. METHODS: Western blotting (WB) and quantitative reverse-transcription polymerase chain reaction were performed to analyze the relationships between TGF-ß1 concentration and NIS expression. After transfecting BCPAP cells with siRNAs, the Rap1GAP interference model was successfully established. Then, the expression and nuclear localization of TGF-ß1 and pathway-related proteins were detected. Flow cytometry was applied to analyze cell apoptosis and cycle. WB was performed to detect apoptotic-related proteins. Wound healing and transwell assays were used to measure cell migration and invasion. EDU was performed to detect cell proliferative activity. RESULTS: The results suggested that TGF-ß1 could significantly inhibit the expression of NIS in both mRNA and protein levels. In BCPAP cells transfected with siRNA-Rap1GAP, the expression levels of TGF-ß1, Foxp3, and p-Smad3 were significantly increased. By applying immunofluorescence assay, the nuclear localizations of TßR-1 and p-Smad3 were found to be activated. Moreover, anti-TGF-ß1 can reverse the decrease in NIS expression caused by downregulation of Rap1GAP. Additionally, the knockdown of Rap1GAP could alter the cell apoptosis, cycle, migration, invasion, and proliferation of BCPAP. CONCLUSION: The downregulation of Rap1GAP expression can activate the TGF-ß/Smad3 pathway to inhibit NIS expression and alter the tumor cell functions of PTC.

Analysis of T lymphocyte-related biomarkers in pancreatic cancer.

BACKGROUND: Pancreatic cancer remains one of the most lethal cancers. OBJECTIVE: This study aimed to analyze T cell-related biomarkers and their molecular network in pancreatic cancer. METHODS: RNAseq sequencing data and clinical data of pancreatic cancer were obtained from TCGA database. The STromal and Immune cells in MAlignant Tumours using Expression data (ESTIMATE) algorithm was used to screen the DEGs related to the tumor immune cells. The pearson correlation analysis were used to analyze the relationships between DEGs and T cells. Additionally, the T cell-related DEGs were subjected to protein-protein interaction, competing endogenous RNA (ceRNA), and chemical small molecule-target network construction. Furthermore, the prognosis-associated DEGs were screened. RESULTS: A total of 412 stromal score-associated and 312 immune score-associated DEGs were obtained. From these DEGs, 50 CD4+ T cell-related genes and 13 CD8+ T cell-related genes were selected. The PPI networks associated with immune cell-related genes were constructed and found that CD22, SELL, and OLR1 had higher degrees in the PPI network. The number of ceRNA regulatory relation pairs obtained from CD4+ T cells and CD8+ T cells were 59 and 48, respectively. Additionally, both CD4+ T cell- and CD8+ T cell-related genes predicted 29 small molecules. CXCL9 and GIMAP7 were screened out from CD4+ T cell-related genes, which were related with the survival of pancreatic cancer. CONCLUSION: We mapped T cell-related gene profile in pancreatic cancer and constructed their potential regulatory network.

Nine Genes Mediate the Therapeutic Effects of Iodine-131 Radiotherapy in Thyroid Carcinoma Patients.

BACKGROUND: Thyroid carcinoma (THCA) is one of the most common malignancies of the endocrine system, which is usually treated by surgery combined with iodine-131 (I131) radiotherapy. AIMS: This study is aimed at exploring the potential targets of I131 radiotherapy in THCA. METHODS: The RNA-sequencing data of THCA in The Cancer Genome Atlas database (including 568 THCA samples) was downloaded. The differentially expressed genes (DEGs) between the tumour samples whether or not subjected to I131 radiotherapy were identified using edgeR package. Using the WGCNA package, the module that was relevant with I131 radiotherapy was selected. The intersection genes of the hub module nodes and the DEGs were obtained as hub genes, followed by the function and pathway enrichment analyses using the clusterProfiler package. Moreover, the protein-protein interaction (PPI) network for the hub genes was constructed using Cytoscape software. In addition, more important hub genes were analysed with function mining using the GenCLiP2 online tool. The qPCR analysis was used to verify the mRNA expression of more important hub genes in THCA tissues. RESULTS: There were 500 DEGs (167 upregulated and 333 downregulated) between the two groups. WGCNA analysis showed that the green module (428 nodes) exhibited the most significant correlation with I131 radiotherapy. A PPI network was built after the identification of 53 hub genes. In the PPI network, CDH5, KDR, CD34, FLT4, EMCN, FLT1, ROBO4, PTPRB, and CD93 exhibited higher degrees, which were mainly implicated in the vascular function. The relative expression of nine mRNAs in the THCA tissues treated with I131 was lower. CONCLUSION: I131 radiotherapy might exert therapeutic effects by targeting CDH5, KDR, CD34, FLT4, EMCN, FLT1, ROBO4, PTPRB, and CD93 in THCA patients.

BRAFV600E mutation and NIS expression in papillary thyroid carcinomas / 中华普通外科杂志

Objective To investigate BRAFV600E mutation and sodium iodide symporter (NIS) expression and its clinical significance in papillary thyroid carcinomas (PTC).Methods BRAFV600E mutation was evaluated by direct sequencing and BRAFV600E mutation was determined in 40 cases of PTC.NIS expression was examined by means of immunohistochemistry.The relationship between BRAFV600E mutation and the clinicopathologic features of PTC was analyzed.The relationship between NIS expression and BRAFV600E mutation in PTC was analyzed.Results Positive BRAFV600E mutation was determined in 23 of 40 cases of PTC (57.5％),whereas positive NIS expression was showed in 7 of 40 cases (12.5％).BRAFV600E mutation was associated with extrathyroid invasion and a high risk of disease recurrence in PTC (P ＜ 0.05).Positive NIS expression was found in only one of 23 cases of PTC with BRAFV600E mutation,and positive NIS expression was associated with a statistically significant lower BRAFV600E mutation in PTC (P =0.011).Conclusions BRAFV600E mutation might be associated with higher aggressiveness,higher disease recurrence and a poorer prognosis.Lower NIS expression may be responsible for poor 131I uptake in

Expression of Rap1GAP and its methylation status in papillary thyroid carcinoma / 中华内分泌代谢杂志

The expression of Rap1 GAP protein was detected in 69 cases of papillary thyroid carcinoma and adjacent normal thyroid tissues with immunohistochemistry method.Methylation of Rapl GAP gene was analyzed by methylation-specific-PCR (MSP) in these tissues.The immunohistochemistry results indicated that the Rap1GAP protein was down-regulated in tumor tissues of 54 ( 78％ ) cases compared with normal thyroid tissues.Statistical analysis demonstrated that the decreased level of Rap1 GAP protein expression was significantly correlated with the tumor stage T according to American Joint Committee on Cancer ( AJCC,P =0.043 ).The MSP results demonstrated that 46 cases of Rap1GAP gene methylation were detected in 54 cases with down-regulated expression of Rap1GAP (66.7％),but only 1 case of methylation was found in 15 cases without obvious change of Rap1GAP expression (6.67％),showing significant difference ( P＜0.01 ).There was no methylation in normal thyroid tissues.These results suggest that raised methylation of promoter region may contribute to the low expression of Rap1GAP protein in papillary thyroid carcinoma.