microRNA-599 promotes apoptosis and represses proliferation and epithelial-mesenchymal transition of papillary thyroid carcinoma cells via downregulation of Hey2-depentent Notch signaling pathway.

Although papillary thyroid carcinoma (PTC) has a favorable prognosis after surgical or medical treatment, its survival rate is still very low. Therefore, finding more reliable therapy methods to limit PTC is a necessity. Compelling evidence has implicated the role of microRNAs (miRNAs or miRs) in PTC. This study aims at investigating the possible effect of microRNA-599 (miR-599) on proliferation, apoptosis, and epithelial-mesenchymal transition (EMT) of PTC cells by targeting Hey2 gene. Differentially expressed genes/miRNAs associated with PTC were screened based on microarray analysis. Then, the expression of the candidate gene, as well as, the regulatory miRNA were detected in PTC cells, the related signaling pathway was verified. Afterward, the relationship between the miR and the candidate gene was verified by dual-luciferase reporter gene assay. Subsequently, the effects of overexpressed miR and silenced candidate gene on cell proliferation, cell apoptosis, EMT, migration, and invasion were detected. In PTC tissues and cells, miR-599 was downregulated while Hey2 expressed highly. Hey2 is a target gene of miR-559. In addition, the expression of Bax and E-cadherin was elevated while that of Hey2, Notch1, Delta-like1, Hes1, N1ICD, Jagged1, Snail, Slug, N-cadherin and Vimentin, and Bcl-2 was reduced in cells treated with upregulated miR-599 or downregulated Hey2. Moreover, miR-599 overexpression or Hey2 silencing inhibited cell proliferation, migration, invasion, along with EMT but promoted apoptosis. This study verified that miR-599 promotes apoptosis and represses proliferation, EMT of PTC cells through inactivating the Notch signaling pathway by downregulating Hey2, which has great clinical significance for PTC treatment.

Overexpression of long noncoding RNA SLC26A4-AS1 inhibits the epithelial-mesenchymal transition via the MAPK pathway in papillary thyroid carcinoma.

Papillary thyroid carcinoma (PTC) is recognized as one of the most prevalent types of thyroid cancer with poor prognosis. Long noncoding RNA (lncRNA) has undergone an intensive study for their involvement in tumor treatment. This study intends to unravel the association of lncRNA SLC26A4-AS1 with PTC. Initially, PTC-related expression profiling data (GSE33630) was utilized to screen differentially expressed lncRNAs in PTC and the underlying mechanisms involved with the mitogen-activated protein kinase (MAPK) pathway. Moreover, PTC tumor tissues and paracancerous tissues were arranged to determine expressions of TP53, SLC26A4-AS1, and genes related to epithelial-mesenchymal transition (EMT) and the MAPK pathway. Furthermore, SLC26A4-AS1 was overexpressed or underexpressed and JNK was underexpressed through cell transfection to examine the effect of SLC26A4-AS1 on PTC via MAPK pathway. Besides, tumor formation in nude mice was used to verify the fore experiment. LncRNA SLC26A4-AS1 regulating TP53 had the potential to participate in PTC by regulating the MAPK pathway. SLC26A4-AS1 was expressed poorly in PTC. Notably, SLC26A4-AS1 elevated E-cadherin expression while it reduced that of ERK and Vimentin. In addition, the overexpression of SLC26A4-AS1 inactivated the MAPK pathway by promoting TP53 and decreased cell migration, proliferation, and invasion. In addition to all these effects, the overexpression of SLC26A4-AS1 promoted apoptosis of TPC-1 cells. Additionally, the overexpression of lncRNA SLC26A4-AS1 reduced xenograft tumor volume in nude mice. Furthermore, the effect of SLC26A4-AS1 overexpression was found to be promoted after the MAPK pathway inactivation. Taken together, the overexpression of lncRNA SLC26A4-AS1 coffered anti-oncogenic effects on PTC through the inactivation of the MAPK pathway.

Experimental chronic hepatitis B infection of neonatal tree shrews (Tupaia belangeri chinensis): a model to study molecular causes for susceptibility and disease progression to chronic hepatitis in humans.

BACKGROUND: Hepatitis B virus (HBV) infection continues to be an escalating global health problem. Feasible and effective animal models for HBV infection are the prerequisite for developing novel therapies for this disease. The tree shrew (Tupaia) is a small animal species evolutionary closely related to humans, and thus is permissive to certain human viral pathogens. Whether tree shrews could be chronically infected with HBV in vivo has been controversial for decades. Most published research has been reported on adult tree shrews, and only small numbers of HBV infected newborn tree shrews had been observed over short time periods. We investigated susceptibility of newborn tree shrews to experimental HBV infection as well as viral clearance over a protracted time period. RESULTS: Forty-six newborn tree shrews were inoculated with the sera from HBV-infected patients or tree shrews. Serum and liver samples of the inoculated animals were periodically collected and analyzed using fluorescence quantitative polymerase chain reaction, enzyme-linked immunosorbent assay, Southern blot, and immunohistochemistry. Six tree shrews were confirmed and four were suspected as chronically HBV-infected for more than 48 (up to 228) weeks after inoculation, including three that had been inoculated with serum from a confirmed HBV-infected tree shrew. CONCLUSIONS: Outbred neonatal tree shrews can be long-term chronically infected with HBV at a frequency comparable to humans. The model resembles human disease where also a smaller proportion of infected individuals develop chronic HBV related disease. This model might enable genetic and immunologic investigations which would allow determination of underlying molecular causes favoring susceptibility for chronic HBV infection and disease establishment vs. viral clearance.

[Expression of epidermal fatty acid-binding protein in cross-species hepatocellular carcinoma].

OBJECTIVE: To evaluate the utility of the cross-species screening strategy for investigating key molecule(s) involved in onset and progression of hepatocellular carcinoma (HCC). METHODS: HCC-related molecule data from our previous studies and in the literature were collected to establish a cross-species dataset. Tissue samples of HCC, non-HCC surrounding liver (para-HCC), and normal liver that were collected from humans, tree shrews and rats. The genes reported to have the most differential expression in HCC were verified by analyzing the mRNA and protein levels by reverse transcription-polymerase chain reaction (RT-PCR) and Western blotting, respectively. RESULTS: The cross-species dataset of HCC-related molecules included four genes: epidermal fatty acid-binding protein (E-FABP), liver (L)-FABP, tyrosine a-ketoglutarate transaminase (TKT), and cytokeratin (CK8). In humans, E-FABP mRNA expression was significantly higher (P less than 0.05) in HCC (0.87+/-0.14 vs. para-HCC: 0.64+/-0.12 and normal liver: 0.67+/-0.07; F=20.910). Similar results were obtained in tree shrew (HCC: 0.87 +/- 0.25 vs. para-HCC: 0.73 +/- 0.19 and normal liver: 0.68+/-0.19; F=3.807) and rat (HCC: 0.97+/-0.22 vs. para-HCC: 0.78+/-0.16 and normal liver: 0.80 +/- 0.13; F=4.482). The Western blotting analyses revealed a similar statistically significant trend. CONCLUSION: The cross-species screening strategy for tumor genes may represent a feasible and convenient process of identifying key molecule(s) for human HCC. E-FABP may be a particularly crucial molecule for hepatocarcinogenesis.

Genetically modified endothelial progenitor cells with hNotch1.ICN overexpression display facilitated angiogenesis.

BACKGROUND: This study focused on hNotch1.ICN overexpression and investigated how it affects the biological behavior of endothelial progenitor cells (EPC) in vitro. METHODS: CCK 8 assay was used to evaluate overexpressed hNotch1.ICN to determine how to influence EPCs' survivability. The Annexin V/PI method was used to detect overexpressed hNotch1.ICN and to influence EPC apoptosis. A flow cytometry instrument was used to assess the overexpression of hNotch1.ICN and determine how to influence the EPC cell cycle. Transwell was used to investigate how overexpressed hNotch1.ICN EPCs migrate using their endothelial ability and adhesive ability with activated endothelial cells and angiogenesis ability. After lentivirus gene transfection, qPCR and Western blot were used to detect a notch signaling pathway downstream of the signaling molecules Hes 1 and Hey 1 mRNA and protein expression. The role of the Notch.1 intracellular domain as a candidate EPC regulator with its differential expression and Hes 1 and Hey 1 expression of Notch downstream signaling molecules in separate groups was analyzed. RESULTS: A detailed analysis revealed an over-expressed hNotch1.ICN gene had no significant effect on canine EPC growth, strengthened EPC antiapoptotic ability, increased numbers of EPCs that underwent cell cycle arrest in the G2 phase, inhibited EPCs differentiation, and enhanced Hes 1 and Hey 1 expression. Moreover, an over-expressed hNotch1 ICN gene promotes EPCs to migrate across ECs, promotes EPCs to adhere to activating endothelial cells, and induces angiogenesis in vitro. CONCLUSIONS: Over-expressed hNotch1.ICN onto EPCs could be used as a potential candidate to treat many ischemic diseases.

[Long-term observation of hepatitis B virus (HBV) replication in new-born tree shrews inoculated with HBV].

OBJECTIVE: To observe the hepatitis B virus (HBV) replication in the tree shrews that were inoculated with HBV at neonatal period. METHODS: Six new-born tree shrews were inoculated with human HBV positive serum. Blood samples and liver biopsies were collected at different time points after inoculation. The HBV infection markers were tested by nested polymerase chain reaction (nPCR), fluorescence quantitative polymerase chain reaction (FQ-PCR), Southern blot, ELISA and immunohistochemistry staining. The liver tissues were observed under electron and light microscope. RESULTS: 48 weeks after inoculation, HBV DNA and HBV cccDNA were detected in the serum and liver samples of three animals (number 1, 2 and 6) by nPCR. The copy-numbers of HBV DNA detected by FQ-PCR in their serum and liver samples were 103 and-104/ml respectively,and the total DNA in 1microg liver tissue was 107-108. Southern blot indicated that HBV replication intermediates such as HBV cccDNA and HBV ssDNA was detectable in liver tissues. HBsAg was detected by ELISA, and immunohistochemical staining showed a gradual increase of HBsAg-positive liver cells. High copy number of HBV DNA and suspected HBV EM particles could be detected in the liver samples from one of the three animals that have survived more than 2 years after inoculation. The other three animals showed low HBV DNA copy number, and the rest of the signs of HBV infection were negative or transiently positive. CONCLUSIONS: Neonatal tree shrews can be infected with human HBV. HBV can replicate inside the liver cells of tree shrew.

Identifying gene modules of thyroid cancer associated with pathological stage by weighted gene co-expression network analysis.

Thyroid cancer is the most common type of endocrine tumor. The TNM classification remains a standard for treatment determination and predicting prognosis in thyroid cancer. The genes modules associated with the progression of papillary thyroid carcinoma (PTC) were not clear. We applied a weighted gene co-expression network analysis (WGCNA) and differential expression analysis to systematically identified co-expressed gene modules and hub genes associated with PTC progression based on The Cancer Genome Atlas (TCGA) PTC transcriptome sequencing data. An independent validation cohort, GSE27155, was used to evaluate the preservation of gene modules. We identified two co-expressed genes modules associated with progression of PTC. Enrichment analysis indicated that the two modules were enriched in angiogenesis and extracellular matrix organization. DCN, COL1A1, COL1A2, COL5A2 and COL3A1 were hub genes in the co-expressed network. We systematically identified co-expressed gene modules and hub genes associated with PTC progression for the first time, which provided insights into the mechanisms underlying PTC progression and some potential targets for the treatment of PTC.