Subject(s)
Macula Lutea/pathology , Macular Edema/etiology , Pregnancy Complications , Retinal Vein Occlusion/complications , Adult , Female , Fluorescein Angiography , Follow-Up Studies , Fundus Oculi , Humans , Macular Edema/diagnosis , Pregnancy , Remission, Spontaneous , Retinal Vein Occlusion/diagnosis , Time Factors , Tomography, Optical CoherenceABSTRACT
Choroidal neovascularization (CNV) in age-related macular degeneration usually causes blindness. We established a novel targeted inhibitor for CNV in age-related macular degeneration. The inhibitor CR2-sFlt 1 comprises a CR2-targeting fragment and an anti-vascular endothelial growth factor (VEGF) domain (sFlt 1). The targeting of CR2-sFlt 1 was studied using the transwell assay in vitro and frozen sections in vivo using green fluorescent labeling. Transwell assay results showed that CR2-sFlt 1 migrated to the interface of complement activation products and was present in the retinal tissue of the CR2-sFlt 1-treated CNV mice. Treatment effects were assessed by investigating the VEGF concentration in retinal pigmented epithelial cell medium and the thickness of the CNV complex in the mice treated with CR2-sFlt 1. CR2-sFlt 1 significantly reduced the VEGF secretion from retinal pigmented epithelial cells in vitro and retarded CNV progress in a mouse model. Expression analysis of VEGF and VEGFRs after CR2-sFlt 1 intervention indicated the existence of feedback mechanisms in exogenous CR2-sFlt 1, endogenous VEGF, and VEGFR interaction. In summary, we demonstrated for the first time that using CR2-sFlt 1 could inhibit CNV with clear targeting and high selectivity.
Subject(s)
Choroidal Neovascularization/drug therapy , Macular Degeneration/drug therapy , Retina/drug effects , Retinal Pigment Epithelium/drug effects , Vascular Endothelial Growth Factor A/chemistry , Vascular Endothelial Growth Factor Receptor-1/chemistry , Animals , Choroidal Neovascularization/physiopathology , Disease Models, Animal , Macular Degeneration/complications , Macular Degeneration/physiopathology , Mice , Retina/chemistry , Vascular Endothelial Growth Factor A/metabolism , Vascular Endothelial Growth Factor Receptor-1/metabolismABSTRACT
Melanoma is a malignant tumor of the melanocytes. microRNAs (miRNAs) are emerging as important regulators of cancer-related processes. A thorough understanding of miRNAs in melanoma progression is important for developing new therapeutic targets. miRNA expression was detected by quantitative PCR. In vitro, MTT assay, colony formation assay, invasion assay and flow cytometry analysis were performed to test the effect of miR-573 on melanoma cells. The effect of miR-573 in vivo was validated using a murine xenograft model. Using quantitative PCR, we found that the expression levels of miR-573 were lower in melanoma tissues and cell lines compared to normal skin tissues. miR-573 upregulation inhibited melanoma cell proliferation and invasion, and overexpression of melanoma cell adhesion molecule (MCAM) could alleviate the effect of miR-573 on melanoma cells. In vivo, miR-573 overexpression groups showed lower rates of tumor growth compared with the control group. In conclusion, our results demonstrate that the elevated MCAM expression due to miR-573 reduction is essential in melanoma initiation and progression.
Subject(s)
CD146 Antigen/metabolism , Melanoma/genetics , Melanoma/metabolism , MicroRNAs/metabolism , Animals , Apoptosis , CD146 Antigen/biosynthesis , Cell Line, Tumor , Cell Proliferation , Disease Progression , Gene Expression Regulation, Neoplastic , Humans , Mice , MicroRNAs/genetics , Neoplasm Invasiveness/genetics , Neoplasm Transplantation , Up-Regulation , Xenograft Model Antitumor AssaysABSTRACT
Aberrant expression of microRNAs (miRNAs) has been implicated in cancer initiation and progression. In this study, we found that microRNA-34a (miR-34a) is significantly downregulated in glioblastoma multiforme (GBM) specimens compared with normal brain tissues. Growth curve and colony formation assays revealed that miR-34a suppresses proliferation of U373MG and SHG44 glioblastoma cells. Overexpression of miR-34a could induce apoptosis of glioblastoma cells. Also, we identified notch1 as a direct target gene of miR-34a. Knockdown of notch1 showed similar cellular functions as overexpression of miR-34a both in vitro and in vivo. Collectively, our findings show that miR-34a is downregulated in GBM cells and inhibits GBM growth by targeting notch1.
Subject(s)
Cell Proliferation , Glioblastoma/genetics , MicroRNAs/genetics , Receptor, Notch1/genetics , 3' Untranslated Regions , Animals , Cell Line, Tumor , Female , Gene Expression Regulation, Neoplastic , Genes, Reporter , Glioblastoma/metabolism , Humans , Luciferases, Renilla/biosynthesis , Luciferases, Renilla/genetics , Mice , Mice, Nude , MicroRNAs/metabolism , Neoplasm Transplantation , RNA Interference , Receptor, Notch1/metabolism , Transcription, GeneticABSTRACT
BACKGROUND: Recent evidence shows that complements are closely related to the occurrence of choroidal neovascularization (CNV). We studied the effect of complement 5b-9 complex (C5b-9) on membrane permeability and molecular biological behavior in cultured human retinal pigment epithelium (RPE) cells and considered the role of C5b-9 in CNV. MATERIAL/METHODS: Human RPE cells were exposed to different concentrations of C5b-9 for 24 hours, then observed through light and electron microscopy. The dynamics of calcium ion change in cells exposed to sublysis C5b-9 were analyzed by confocal laser scanning microscope, and the amount of VEGF and TGF-beta2 mRNA was determined by reverse transcription polymerase chain reaction (RT-PCR) RESULTS: RPE cells were destroyed when exposed to 80 microg/ml and 40 microg/ml C5b-9. The structure of RPE cells was not obviously changed when exposed to 20 microg/ml or less C5b-9; however, pigment granules are released from the cell membrane when observed using electron microscopy. In most of the cells, calcium fluorescence intensity increased rapidly after the deposition of C5b-9, to a peak at 4 min, lasted for about 6 min, and then began to decrease. The expression of VEGF and TGF- beta2 mRNA in RPE cells with C5b-9 was increased at 4 h and decreased at 24 h, but they were higher than in the control group. CONCLUSIONS: These observations suggest C5b-9 can induce a change in membrane permeability, an increase in cytoplasmic calcium ion concentration, and significant up-regulation of angiogenic factors in cultured RPE cells, which may be one of many potential mechanisms of CNV formation.
