Many human genetic diseases, including Hutchinson-Gilford progeria syndrome (HGPS), are caused by single point mutations. HGPS is a rare disorder that causes premature aging and is usually caused by a de novo point mutation in the LMNA gene. Base editors (BEs) composed of a cytidine deaminase fused to CRISPR/Cas9 nickase are highly efficient at inducing C to T base conversions in a programmable manner and can be used to generate animal disease models with single amino-acid substitutions. Here, we generated the first HGPS monkey model by delivering a BE mRNA and guide RNA (gRNA) targeting the LMNA gene via microinjection into monkey zygotes. Five out of six newborn monkeys carried the mutation specifically at the target site. HGPS monkeys expressed the toxic form of lamin A, progerin, and recapitulated the typical HGPS phenotypes including growth retardation, bone alterations, and vascular abnormalities. Thus, this monkey model genetically and clinically mimics HGPS in humans, demonstrating that the BE system can efficiently and accurately generate patient-specific disease models in non-human primates.
Animals ; Disease Models, Animal ; Female ; Gene Editing ; Humans ; Lamin Type A/metabolism* ; Macaca fascicularis ; Progeria/pathology*

Hutchinson-Gilford progeria syndrome (HGPS) and Werner's syndrome are representative types of progeroid syndrome. LMNA (Lamin A/C) gene mutation with atypical Werner's syndrome have recently been reported. Atypical Werner's syndrome with the severe metabolic complications, the extent of the lipodystrophy is associated with A133L mutation in the LMNA gene and these patients present with phenotypically heterogeneous disorders. We experienced a 15-yr-old Korean female with progeroid features, generalized lipodystrophy, hypertriglyceridemia, fatty liver, steatohepatitis, and type 2 diabetes mellitus. Skin fibroblasts from the patient showed marked abnormal nuclear morphology, compared with that from normal persons. Gene analysis revealed that this patient had T506del of exon 2 in the LMNA gene. We report here the first case of atypical Werner's syndrome with frameshift mutation that was caused by T506del.
Adolescent ; DNA/*genetics ; Exons ; Female ; Genetic Predisposition to Disease ; Humans ; Lamin Type A/*genetics/metabolism ; Lipodystrophy ; *Mutation ; Sequence Analysis, DNA ; Skin/metabolism/pathology ; Werner Syndrome/diagnosis/*genetics/metabolism

BACKGROUNDLaminopathies are a group of rare genetic disorders characterized by multiple-tissue degeneration. We describe a new laminopathy with ovarian cystadenoma and explore its molecular etiology.

METHODSThe case is a 15-year-old girl who presents the prominent progeroid disorders, multiple system degeneration and early-onset cystadenoma of the ovary. Candidate genes including LMNA, ZMPSTE24, PPAR G, INSR and WRN were sequenced to screen for DNA variants. The mRNA and protein expression levels of LMNA were examined in primary fibroblasts. The pathophysiological events such as morphologic alterations, cell senescence, cell proliferation, apoptosis and pRb as well as p53 protein expressions were also investigated in primary fibroblasts.

RESULTSNo mutation was identified in the candidate genes screened. Nuclear abnormalities including nuclear blebs, mislocalization of lamin A/C were evident in the patient fibroblasts. Ultrastructurally, nucleus exhibited nuclear herniation and almost complete loss of peripheral heterochromatin. In addition, lamin C protein expression was markedly reduced whereas lamin A protein level was normal and no prelamin A was detected in the primary fibroblasts. Although the senescence-associated beta-galactosidase staining of patient' cells was negative, cells in S phase increased in accompany with a decrease in pRb protein expression. Furthermore, increases in apoptotic cell death and p53 expression were observed.

CONCLUSIONSOur data suggest that selective deficiency of lamin C protein is associated with a case of laminopathy with ovarian cystadenoma. The abnormalities in nuclear structure and alterations in gene expression such as the decrease in pRb and increase in p53 may be responsible for the multiple tissue degeneration.

Adolescent ; Apoptosis ; genetics ; physiology ; Blotting, Northern ; Blotting, Western ; Cell Cycle ; genetics ; physiology ; Cells, Cultured ; Cystadenoma ; genetics ; metabolism ; Female ; Fibroblasts ; cytology ; metabolism ; Humans ; Lamin Type A ; deficiency ; genetics ; metabolism ; Microscopy, Electron, Transmission ; Microscopy, Fluorescence ; Ovarian Neoplasms ; genetics ; metabolism ; Polymerase Chain Reaction

BACKGROUNDMutations in the lamin A/C gene (LMNA) may cause familial dilated cardiomyopathy (dilated cardiomyopathy) characterized by early onset atrio-ventricular block (A-V block) before the manifestation of dilated cardiomyopathy and high risk of sudden death due to ventricular arrhythmia, which is very similar to the phenotype of gap junction related heart disease. This study aimed to determine the expression and localization of connexins in neonatal myocytes transfected with wild-type (WT) or mutant LMNA to elucidate how these mutations cause heart diseases.

METHODSWe studied the connexin 43 (Cx43) and connexin 40 (Cx40) expression in cultured neonatal myocytes transfected with wild-type (WT) or mutant LMNA (Glu82Lys (E82K) and Arg644Cys (R644C)) using confocal imaging and Western blotting analysis.

RESULTSCx43 protein expression was reduced by 40% in cells transfected with LMNA E82K than that in cells transfected with WT LMNA cDNA. Confocal imaging showed that the Cx43 located inside the cells by LMNA E82K. By contrast, LMNA E82K mutation had no effect on expression and localization of Cx40. LMNA R644C transfection did not show any significant effects on gap junctions at all.

CONCLUSIONSOur findings suggest that LMNA E82K significantly reduced the Cx43 expression and altered its localization which may be one of the pathological mechanisms underlying LMNA-related heart disease.

Animals ; Atrioventricular Node ; pathology ; Blotting, Western ; Cardiomyopathy, Dilated ; metabolism ; pathology ; Cells, Cultured ; Connexin 43 ; metabolism ; Connexins ; metabolism ; Fluorescent Antibody Technique ; Gap Junctions ; metabolism ; Humans ; Lamin Type A ; genetics ; physiology ; Mutation ; Rats ; Transfection

Through advances in technology, the genetic basis of cancer has been investigated at the genomic level, and many fundamental questions have begun to be addressed. Among several key unresolved questions in cancer biology, the molecular basis for the link between nuclear deformation and malignancy has not been determined. Another hallmark of human cancer is aneuploidy; however, the causes and consequences of aneuploidy are unanswered and are hotly contested topics. We found that nuclear lamina proteins lamin A/C are absent in a significant fraction (38%) of human breast cancer tissues. Even in lamin A/C-positive breast cancer, lamin A/C expression is heterogeneous or aberrant (such as non-nuclear distribution) in the population of tumor cells, as determined by immunohistology and immunofluorescence microscopy. In most breast cancer cell lines, a significant fraction of the lamin A/C-negative population was observed. To determine the consequences of the loss of lamin A/C, we suppressed their expression by shRNA in non-cancerous primary breast epithelial cells. Down-regulation of lamin A/C in breast epithelial cells led to morphological deformation, resembling that of cancer cells, as observed by immunofluorescence microscopy. The lamin A/C-suppressed breast epithelial cells developed aneuploidy as determined by both flow cytometry and fluorescence in situ hybridization. We conclude that the loss of nuclear envelope structural proteins lamin A/C in breast cancer underlies the two hallmarks of cancer aberrations in nuclear morphology and aneuploidy.
Aneuploidy ; Breast Neoplasms ; genetics ; metabolism ; pathology ; Cell Proliferation ; Down-Regulation ; Epithelial Cells ; metabolism ; Female ; Humans ; Lamin Type A ; genetics ; metabolism ; Mitosis ; Nuclear Envelope ; metabolism ; pathology ; Polyploidy ; RNA, Small Interfering ; genetics

To investigate the effect ofgene down-regulation on early hematopoietic development of zebrafish.Phosphorodiamidate morpholino oligomer (PMO) technology was used to downregulategene expression in Zebrafish. Zebrafish embryos injected phosphorodiamidate morpholino antisense oligonucleotide ofgene mRNA by microinjection at unicellular stage were taken as the experimental group, and those injected meaningless phosphorodiamidate morpholino antisense oligonucleotide were taken as the control. The embryos were collected at 18, 24, 30 and 36 hpf after the fertilization. The real-time fluorescent quantitative PCR (RT-PCR) and whole embryohybridization methods were used to detect the expression of myeloid hematopoietic transcription factorand erythroid hematopoietic transcription factorin zebrafish.RT-PCR showed that the expressions ofanddecreased in the experimental group compared with the control group (all<0.05). Whole embryohybridization showed that the blue-black positive hybridization signals ofandin experimental group were shallow than those in the control group.Myeloid hematopoietic and erythroid hematopoietic of zebrafish are blocked with the downregulation ofgene.
Animals ; Down-Regulation ; genetics ; Embryo, Nonmammalian ; physiopathology ; GATA1 Transcription Factor ; genetics ; metabolism ; Gene Knockdown Techniques ; Hematopoiesis ; In Situ Hybridization ; Lamin Type A ; genetics ; physiology ; Proto-Oncogene Proteins ; genetics ; metabolism ; Trans-Activators ; genetics ; metabolism ; Zebrafish ; embryology ; genetics

Hutchinson-Gilford progeria syndrome (HGPS) and Werner syndrome (WS) are two of the best characterized human progeroid syndromes. HGPS is caused by a point mutation in lamin A (LMNA) gene, resulting in the production of a truncated protein product-progerin. WS is caused by mutations in WRN gene, encoding a loss-of-function RecQ DNA helicase. Here, by gene editing we created isogenic human embryonic stem cells (ESCs) with heterozygous (G608G/+) or homozygous (G608G/G608G) LMNA mutation and biallelic WRN knockout, for modeling HGPS and WS pathogenesis, respectively. While ESCs and endothelial cells (ECs) did not present any features of premature senescence, HGPS- and WS-mesenchymal stem cells (MSCs) showed aging-associated phenotypes with different kinetics. WS-MSCs had early-onset mild premature aging phenotypes while HGPS-MSCs exhibited late-onset acute premature aging characterisitcs. Taken together, our study compares and contrasts the distinct pathologies underpinning the two premature aging disorders, and provides reliable stem-cell based models to identify new therapeutic strategies for pathological and physiological aging.
Aging ; genetics ; physiology ; DNA Helicases ; genetics ; Human Embryonic Stem Cells ; metabolism ; physiology ; Humans ; Kinetics ; Lamin Type A ; genetics ; Mesenchymal Stem Cells ; metabolism ; physiology ; Mutation ; Progeria ; genetics ; physiopathology ; Werner Syndrome ; genetics ; physiopathology

OBJECTIVE: To analyze the expression of vascular endothelial growth factor (VEGF), miR-205, Ezrinand Lamin A/C in ovarian cancer tissues. METHODS: The expression of VEGF in the serum of epithelial ovarian cancer and that of healthy volunteers were detected by enzyme-linked immunosorbent assay; the expressions of vascular endothelial growth factor receptor 1 (VEGFR-1), VEGFR-2, Ezrin and Lamin A/C were detected by immunohistochemistry and the micro-vessel density (MVD) of CD31 was detected by immunohistochemistry in epithelial ovarian cancer, benign ovarian and normal ovarian specimens; and the expression of miR-205, Ezrin and Lamin A/C were detected by real-time PCR in epithelial ovarian cancer, benign ovarian and normal ovarian specimens. RESULTS: The expression of VEGF in the serum of epithelial ovarian cancer patients (116.10± 11.94) was significantly higher than that of healthy volunteers (40.04±4.97, P<0.05). The positive expression rates of VEGFR-1 and VEGFR-2 in the epithelial ovarian cancer specimens were 75.9% and 91.4% respectively, which were significantly higher than that in the benign ovarian and the normal ovarian specimens (P<0.05). No differences were observed in the positive expression rates of VEGFR-1 and VEGFR-2 between the benign ovarian and the normal ovarian specimens (P>0.05). The average length of MVD in the epithelial ovarian cancer specimens (7.56±0.51), was significantly higher than that in the normal ovarian specimens (1.22±0.56, P<0.05) and in the benign ovarian specimens (0.7±0.39, P<0.05). No differences were observed in the average length of MVD between the benign ovarian and the normal ovarian specimens (P>0.05). The relative expression level of miR-205 was 0.106±0.035 in the epithelial ovarian cancer specimens, which was significantly higher than that in the normal ovarian specimens (0.0007±0.0005, P<0.05); the relative expression level of miR-205 in the benign ovarian specimens was (0.0002±0.0002), higher than that in the normal ovarian specimens, but with no significance (P>0.05). The positive expression rates of Ezrin and Lamin A/C in the epithelial ovarian cancer specimens were 51.7% and 60.3%, respectively, which were significantly lower than those in the benign ovarian and the normal ovarian specimens (P<0.05). No differences were observed in the positive expression rates of Ezrin and Lamin A/C between the benign ovarian and the normal ovarian specimens (P>0.05). The relative expression levels of Ezrin and Lamin A/C mRNA in the epithelial ovarian cancer specimens were (0.026±0.003) and (0.060±0.007), respectively, which were significantly lower than those in the normal ovarian specimens (P<0.05). There was no statistical significance between the relative expression level of Ezrin and Lamin A/C mRNA in the epithelial ovarian cancer specimens and that in the benign ovarian specimens (0.029± 0.011, 0.089 ± 0.019; P>0.05) . CONCLUSION VEGF is significantly expressed in the serum of epithelial ovarian cancer patients; and miR-205 is up-regulated in the epithelial ovarian cancer specimens. Ezrin and Lamin A/C are down-regulated in the epithelial ovarian cancer samples. VEGF, miR-205 and target protein may be associated with the invasion and metastasis of epithelial ovarian cancer.
Carcinoma, Ovarian Epithelial ; Cytoskeletal Proteins ; genetics ; metabolism ; Down-Regulation ; Enzyme-Linked Immunosorbent Assay ; Female ; Humans ; Immunohistochemistry ; Lamin Type A ; genetics ; metabolism ; MicroRNAs ; genetics ; metabolism ; Neoplasms, Glandular and Epithelial ; genetics ; metabolism ; Ovarian Neoplasms ; genetics ; metabolism ; RNA, Messenger ; Real-Time Polymerase Chain Reaction ; Vascular Endothelial Growth Factor A ; blood ; Vascular Endothelial Growth Factor Receptor-1 ; metabolism ; Vascular Endothelial Growth Factor Receptor-2 ; metabolism