The Long Noncoding RNA H19 Promotes Fibrotic Processes in Lens Epithelial Cells.

Purpose: The purpose of this study was to investigate the role of lncRNA H19 in epithelial-mesenchymal transition (EMT) and its molecular mechanism in fibrotic cataracts. Methods: TGF-ß2-induced EMT was induced in human lens epithelial cell line (HLECs) and rat lens explants to mimic posterior capsular opacification (PCO) in vitro and in vivo. Anterior subcapsular cataract (ASC) was induced in C57BL/6J mice. The long noncoding RNA (lncRNA) H19 (H19) expression was detected by RT-qPCR. Whole-mount staining of lens anterior capsule was used to detect α-SMA and vimentin. Lentiviruses carrying shRNA or H19 vector were transfected in HLECs to knockdown or overexpress H19. Cell migration and proliferation were characterized by EdU, Transwell, and scratch assay. EMT level was detected by Western blotting and immunofluorescence. The rAAV2 carrying mouse H19 shRNA was injected into ASC model mouse anterior chambers as a gene therapy to determine its therapeutic potential. Results: PCO and ASC models were built successfully. We found H19 upregulation in PCO and ASC models in vivo and in vitro. Overexpression of H19 by lentivirus transfection increased cell migration, proliferation, and EMT. In addition, H19 knockdown by lentivirus suppressed cell migration, proliferation, and EMT levels in HLECs. Moreover, transfection of rAAV2 H19 shRNA alleviated fibrotic area in ASC mouse lens anterior capsules. Conclusions: Excessive H19 participates in lens fibrosis. Overexpression of H19 increases, whereas knockdown of H19 ameliorates HLECs migration, proliferation, and EMT. These results demonstrate H19 might be a potential target for fibrotic cataracts.

Role of surface ectoderm-specific mitofusin 2 in the corneal morphologic development of mice.

Mitofusin 2 (Mfn2) mediates the mitochondrial fusion in dynamic balance between mitochondrial fission and fusion. This study aimed to investigate the role of Mfn2 in mice corneal dysplasia with conditional knockout (CKO) technique. The Mfn2 CKO mice model was established with the Cre-loxP system. Each offspring of Le-Cre +/-; Mfn2 fl/fl (Mfn2 CKO) mice and Mfn2fl/fl (Mfn2 WT) mice was identified by polymerase chain reaction (PCR). Macroscopic observation, immunohistostaining and HE staining were used to evaluate the corneal morphologic development in Mfn2 CKO mice and Mfn2 WT mice. The cells proliferation and apoptosis were detected by BrdU labeling and TUNEL assay. Real-time PCR was used to detect mRNA expression of corneal markers (K12, Col1α1, Pax6, keratocan and NSE). Results showed that Mfn2 CKO mice showed increased corneal thickness, small eyeball from E15.5 to P60 and small eye crack after birth. The corneal stromal thickness significantly increased in Mfn2 CKO mice, and the random arrangement fibers of the corneal stroma increased in Mfn2 CKO mice. The proliferative cells in the cornea of Mfn2 CKO mice were less than in Mfn2 WT mice while the apoptotic cells in the cornea of Mfn2 CKO mice were increased. K12 and Pax6 expression decreased in the cornea and the Col1α1 expression increased in Mfn2 CKO mice as compared to Mfn2 WT mice. The expression of corneal stromal marker Col1α1 in the Mfn2 CKO mice was significantly higher than that in the Mfn2 WT mice. Corneal thickness was mainly caused by corneal stroma collagen proliferation. In conclusion, Mfn2 deletion affects corneal development, especially because of collagen hyperplasia in the corneal stroma.

Overexpression of Nemo-like Kinase Promotes the Proliferation and Invasion of Lung Cancer Cells and Indicates Poor Prognosis.

BACKGROUND: Nemo-like kinase (NLK) is an evolutionarily conserved MAP kinaserelated kinase involved in the pathogenesis of several human cancers. OBJECTIVE: The aim of this study was to investigate the expression and role of NLK in lung cancers, and its underlying mechanisms. METHODS: We examined the expression of NLK in lung cancer tissues through western blot analysis. We enhanced or knocked down NLK expression by gene transfection or RNA interference, respectively, in lung cancer cells, and examined expression alterations of key proteins in the Wnt signaling pathway and in epithelial-mesenchymal transition (EMT). We also examined the roles of NLK in the proliferation and invasiveness of lung cancer cells by cell proliferation, colony formation, and Matrigel invasion assays. RESULTS: NLK expression was found to be significantly higher in lung cancer tissue samples than in corresponding healthy lung tissue samples. Overexpression of NLK correlated with poor prognosis of patients with lung cancer. Overexpression of NLK upregulated ß-catenin, TCF4, and Wnt target genes such as cyclin D1, c-Myc, and MMP7. N-cadherin and TWIST, the key proteins in EMT, were upregulated, while E-cadherin expression was reduced. Additionally, proliferation, colony formation, and invasion turned out to be enhanced in NLK-overexpressing cells. After NLK knockdown in lung cancer cells, we obtained the opposite results. CONCLUSION: NLK is overexpressed in lung cancers and indicates poor prognosis. Overexpression of NLK activates the Wnt signaling pathway and EMT and promotes the proliferation and invasiveness of lung cancer cells.

Odd-skipped related 1 inhibits lung cancer proliferation and invasion by reducing Wnt signaling through the suppression of SOX9 and ß-catenin.

The odd-skipped related 1 (OSR1) gene encodes a zinc-finger transcription factor. The expression and significance of OSR1 in human tumors remains unclear. We found that OSR1 was downregulated in lung cancers, and its expression was correlated with poor differentiation. Overexpression of OSR1 by OSR1 gene transfection into H1299 cells (H1299-OSR1) inhibited the proliferation and invasion of lung cancer cells. Knockdown of OSR1 with small interfering (si)RNA against OSR1 in A549 cells (A549-siOSR1) enhanced the proliferation and invasion of lung cancer cells. Western blot analysis showed that the expression level of GSK3ß increased, while that of p-GSK3ß, nuclear ß-catenin, cyclin D1, c-Myc and matrix metallopeptidase 7 significantly decreased in the H1299-OSR1 cells, and this pattern was reversed in the A549-siOSR1 cells compared to that in the control cells. Furthermore, upregulation of sex-determining region Y-box 9 (SOX9) by SOX9 gene transfection increased the expression of ß-catenin, which was inhibited by OSR1. The mRNA and protein expression levels of SOX9 and ß-catenin were reduced in H1299-OSR1 cells and increased in A549-siOSR1 cells. In conclusion, the expression of OSR1 was more reduced in lung cancer tissues than in normal lung tissues, and was correlated with poor differentiation. OSR1 downregulated the activity of the Wnt signaling pathway by suppressing the expression of SOX9 and ß-catenin.

Structures and Functions of the Envelope Glycoprotein in Flavivirus Infections.

Flaviviruses are enveloped, single-stranded RNA viruses that widely infect many animal species. The envelope protein, a structural protein of flavivirus, plays an important role in host cell viral infections. It is composed of three separate structural envelope domains I, II, and III (EDI, EDII, and EDIII). EDI is a structurally central domain of the envelope protein which stabilizes the overall orientation of the protein, and the glycosylation sites in EDI are related to virus production, pH sensitivity, and neuroinvasiveness. EDII plays an important role in membrane fusion because of the immunodominance of the fusion loop epitope and the envelope dimer epitope. Additionally, EDIII is the major target of neutralization antibodies. The envelope protein is an important target for research to develop vaccine candidates and antiviral therapeutics. This review summarizes the structures and functions of ED I/II/III, and provides practical applications for the three domains, with the ultimate goal of implementing strategies to utilize the envelope protein against flavivirus infections, thus achieving better diagnostics and developing potential flavivirus therapeutics and vaccines.