COL4A3 mutations cause focal segmenta glomerulosclerosis

Focal segmental glomerulosclerosis （FSGS） is a histologically identifiable gtomerular injury often leading to proteinuria and renal failure. To identify its causal genes, whole-exome sequencing and Sanger sequencing were performed on a large Chinese cohort that comprised 40 FSGS families, 50 sporadic FSGS patients, 9 independent autosomal recessive Atport＇s syndrome （ARAS） patients, and 190 ethnically matched healthy controls. Patients with extrarenal manifestations, indicating systemic diseases or other known hereditary renal diseases, were excluded. Heterozygous COL4A3 mutations were identified in five （12.5%） FSGS families and one （2%） sporadic FSGS patient. All identified mutations disrupted highly conserved protein sequences and none of them was found in either public databases or the 190 healthy controls. Of the FSGS patients with heterozygous COL4A3 mutations, segmental thinning of the glomerular base membrane （GBM） was only detected in the patient with electronic microscopy examination results available. Five ARAS patients （55.6%） had homozygous or compound-heterozygous mutations in COL4.43 or COL4A4. Serious changes in the G BM, hearing loss, and ocular abnormalities were found in 100%, 80%, and 40% of the ARAS patients, respectively. Overall, a new sub- group of FSGS patients resulting from heterozygous C01.4A3 mutations was identified. The mutations are relatively frequent in famiUes diagnosed with inherited forms of FSGS. Thus, we suggest screening for C01.4A3 mutations in familial FSGS patients.     

Clonal overgrowth of esophageal smooth muscle cells in diffuse leiomyomatosis-Alport syndrome caused by partial deletion in COL4A5 and COL4A6 genes

This is a study of a patient who manifests all of the features of a diffuse leiomyomatosis-Alport syndrome (DL-ATS), and her two-year-old son who has already been diagnosed with Alport syndrome. Fourteen years ago, the patient underwent a partial esophageal resection followed by a replacement with jejunum. Recently, she underwent a surgical resection of the esophagus due to esophageal dysfunction. Genetic analyses of COL4A5 and COL4A6 on the X-chromosome were efficiently performed using the genomic DNA of her son. We have identified a novel deletion of 194-kb in length, encompassing COL4A5-COL4A6 promoters as well as nearly the entire large intron 1 of COL4A5 and intron 2 of COL4A6. To uncover the relationship of the esophagus-specific occurrence of the tumor and the expression of those genes, immunohistochemical analyses of type IV collagen α chains were conducted in the non-affected individuals. The esophageal smooth muscle-specific expression of α5(IV) and α6(IV) chains in the gastrointestinal tract was observed. Moreover, CAG repeat analysis of the androgen receptor gene and an immunohistochemical analysis in the leiomyoma revealed clonal overgrowth of the cells which received X-inactivation on the non-affected allele. These results may suggest that the dominant effect was caused by the partial deletion of the esophageal smooth muscle-specific genes, COL4A5 and COL4A6.     

Silencing of CA1 mRNA in tumour cells does not change the gene expression of the extracellular matrix proteins

We report the silencing of CA1 mRNA in PC3 and MDA cells. The levels of mRNA coding CA1 protein in the knock‐down mRNA (CA1 siRNA) cells have been measured by RT‐PCR and were approximately 5% (PC3) and 20% (MDA‐MB‐231), respectively, of the level of control (Mock siRNA) used during silencing. In PC3 and MDA‐MB‐231 cells, the mRNAs for COL1A1 and COL4A4 were up‐regulated. The mRNAs for CTHRC1, LAMC2, and WNT7B were not changed when compared to the control. The morphology of the cells during the treatments remained the same. On the Western blots, the lysate from the silenced cells showed lower levels of CA I as well.     

A novel heterozygous COL4A4 missense mutation in a Chinese family with focal segmental glomerulosclerosis

Focal segmental glomerulosclerosis (FSGS) is the most common glomerular histological lesion associated with high‐grade proteinuria and end‐stage renal disease. Histologically, FSGS is characterized by focal segmental sclerosis with foot process effacement. The aim of this study was to identify the disease‐causing mutation in a four‐generation Chinese family with FSGS. A novel missense mutation, c.1856G>A (p.Gly619Asp), in the collagen type IV alpha‐4 gene (COL4A4) was identified in six patients and it co‐segregated with the disease in this family. The variant is predicted to be disease‐causing and results in collagen IV abnormalities. Our finding broadens mutation spectrum of the COL4A4 gene and extends the phenotypic spectrum of collagen IV nephropathies. Our study suggests that exome sequencing is a cost‐effective and efficient approach for identification of disease‐causing mutations in phenotypically complex or equivocal disorders. Timely screening for COL4A3/COL4A4 mutations in patients with familial FSGS may help both accurately diagnose and treat these patients.     

Vascular Ehlers-Danlos syndrome

Vascular Ehlers-Danlos syndrome, also known as Ehlers-Danlos syndrome type IV, is a life-threatening inherited disorder of connective tissue, resulting from mutations in the COL3A1 gene coding for type III procollagen. Vascular EDS causes severe fragility of connective tissues with arterial and gastrointestinal rupture, and complications of surgical and radiological interventions. As for many rare orphan diseases, delay in diagnosis is common, even when the clinical features are typical, leading to inadequate or inappropriate treatment and management. In childhood many individuals with vascular EDS are first thought to have coagulation disorders. In adulthood, four main clinical findings, including a striking facial appearance, easy bruising, translucent skin with visible veins and rupture of vessels, gravid uterus or intestines, contribute to the diagnosis, which can be confirmed by SDS-PAGE studies of type III procollagen molecules synthesis by cultured fibroblasts or by the identification of a mutation in the COL3A1 gene coding for type III procollagen. Vascular EDS is inherited as an autosomal dominant trait. Varied molecular mechanisms have been observed and, of the mutations described to date, most have been unique to each family or "private", with no correlation between genotype and phenotype. Vascular EDS is of particular importance to surgeons, radiologists, obstetricians and geneticists since, although there is currently no specific treatment for the condition, knowledge of the diagnosis may help in the management of visceral complications, pregnancy and genetic counseling.     

一性连锁Alport综合征中国家系COL4A5基因新突变位点的检测

通过PCR和直接测序的方法,对一性连锁Alport综合征家系17个受检个体的COL4A5基因所有51个外显子及其相邻内含子的DNA序列进行检测。结果发现,在第26外显子2240位点,男患者存在C碱基缺失(2240delc),女患者存在杂合缺失,同时对女患者相应的PCR产物进行克隆和测序以验证PCR测序结果的可靠性,而在正常家系成员和80例对照中均未发现此位点异常,说明2240delc为引起该家系临床病变的突变位点,不是多态性位点。在性连锁Alport综合征中,COL4A5基因的这个单碱基缺失突变位点为首次报道。     

High expression of COL5A2, a member of COL5 family,indicates the poor survival and facilitates cell migration in gastric cancer

Background: Gastric cancer (GC) metastasis determines the prognosis of patients, and exploring the molecular mechanism of GC metastasis is expected to provide a theoretical basis for clinical treatment. Recent studies have shown that extracellular matrix protein is closely related to GC metastasis. The present study aimed to explore the expression profile and role of COL5A2, as an extracellular matrix protein, in GC.Methods: The expression, overall survival, and progression-free survival data of COL5 family members were extracted from The Cancer Genome Atlas (TCGA) database, respectively. Weighted gene co-expression network analysis of the {"type":"entrez-geo","attrs":{"text":"GSE62229","term_id":"62229"}}GSE62229 database was performed out to identify modules and associated genes.Results: COL5A2 was selected as our research target in the TCGA database, and was also verified in the {"type":"entrez-geo","attrs":{"text":"GSE62229","term_id":"62229"}}GSE62229 and {"type":"entrez-geo","attrs":{"text":"GSE15459","term_id":"15459"}}GSE15459 datasets. COL5A2 was up-regulated in GC tissues by paraffin immunohistochemistry and RT-qPCR. The prognosis of patients with low COL5A2 expression was better than that of patients with high COL5A2 expression. Scratch and migration experiments showed that knockdown of COL5A2 decreased the migration ability of gastric cancer cells compared with the control group. In vivo, mice with tail vein injection COL5A2 knockdown had fewer and smaller metastatic nodules in liver. GSEA results showed that the TCGA and {"type":"entrez-geo","attrs":{"text":"GSE62229","term_id":"62229"}}GSE62229 samples were significantly enriched in several well-known cancer-related pathways, such as the TGF-β, MAPK, and JAK2 signaling pathways.Conclusion: COL5A2 was most closely related to advanced GC among COL5 family members. High COL5A2 expression is associated with a poor prognosis, and may be a novel therapeutic target for GC.     

Identification and molecular characterization of two novel mutations in COL1A2 in two Chinese families with osteogenesis imperfecta

Osteogenesis imperfecta (OI, also known as brittle bone disease) is caused mostly by mutations in two type Ⅰ collagen genes, COL1A1 and COL1A2 encoding the pro-α1 (Ⅰ) and pro-α2 (Ⅰ) chains of type Ⅰ collagen, respectively. Two Chinese families with autosomal dominant OI were identified and characterized. Linkage analysis revealed linkage of both families to COL1A2 on chromosome 7q21.3-q22.1. Mutational analysis was carried out using direct DNA sequence analysis. Two novel missense mutations, c.3350A＞G and c.3305G＞C, were identified in exon 49 of COL1A2 in the two families, respectively. The c.3305G＞C mutation resulted in substitution of a glycine residue (G) by an alanine residue (A) at codon 1102 (p.G1102A), which was found to be mutated into serine (S), argine (R), aspartic acid (D), or valine (V) in other families. The c.3350A＞G variant may be a de novo mutation resulting in p.Y1117C. Both mutations co-segregated with OI in respective families, and were not found in 100 normal controls. The G1102 and Y1117 residues were evolutionarily highly conserved from zebrafish to humans. Mutational analysis did not identify any mutation in the COX-2 gene (a modifier gene of OI). This study identifies two novel mutations p.G1102A and p.Y1117C that cause OI, significantly expands the spectrum of COL1A2 mutations causing OI, and has a significant implication in prenatal diagnosis of OI.     

The COL5A1 genotype is associated with range of motion

[Purpose]

The aim of our study was to investigate the association between COL5A1 genotype and Range of Motion as measured by the passive straight leg raise (SLR) and whole body join laxity (WBJL) in Asian population.

[Methods]

One hundred and seventy seven participants including Korean and Japanese college students (male = 109, female = 68) participated in the study. Each subject performed the passive straight leg raise and whole body join laxity test. Genotyping for the COL5A1 (rs 12722) polymorphism was performed using the TaqMan approach. The COL5A1 genotype exhibited a Hardy-Weinberg equilibrium distribution in our population.

[Results]

The physical parameters including height, weight, and BMI were higher in < 90° group than > 90° group. The SLR exhibited significant difference among the COL5A1 group. However, the WBJL did not differ significantly among the COL5A1 genotype, but significant difference was seen in CC genotype when compared to CT (2.99 ± 1.72) or TT (2.70 ± 1.52) genotype.

[Conclusion]

We concluded that COL5A1 gene polymorphism is associated with increased SLR ROM in Asian population.     

Mutation c.359_363delGTATTinsATAC in the COL4A5 Causes alport syndrome in a Chinese family

The X-linked form of Alport syndrome is associated with mutations in the COL4A5 gene, which is located at Xq22.3 and encodes the α5 chain of type IV collagen. Here we clinically characterized a Chinese family with Alport Syndrome, but no ocular or hearing abnormalities have been observed in any patient in the family. Through Linkage analysis and direct DNA sequencing, a novel complex deletion/insertion mutation c.359_363delGTATTinsATAC in the COL4A5 gene was identified in the family. The mutation was found in all affected family members, but was not present in the unaffected family individuals or the 200 controls. The predicted mutant protein in the family is a truncated protein consisting of only 153 residues. Our report for the first time revealed that the frameshift mutation in the type IV collagen chain α5 causes only renal disease, without extrarenal lesion. Our study broadens genotypic and phenotypic spectrum of COL4A5 mutations associated with Alport syndrome.     

Effects of clinorotation on COL1A1-EGFP gene expression

Bone-formation related gene plays a critical role in bone loss induced by space microgravity, however the exact mechanism is unclear. In this study, we aim to investigate the effect of microgravity on the activity of α 1(I) collagen (COL1A1) gene promoter and the expression of osteoblast-related genes. COL1A1 promoter was digested by restriction enzymes resulting in three DNA fragments. The fragments were ligated with the enhanced green fluorescent protein report gene, and subcloned into expression vectors. ROS17/2.8 cells transfected by these vectors were screened by G418, and enhanced green fluorescent protein (EGFP) positive colonies were isolated and cultured under clinostat condition. EGFP and Collagen type I expression level were detected by fluorescence intensity analysis and immunocytochemistry methods respectively. The results showed that the expression of EGFP and collagen type I was increased 24 h, 48 h after the cells were cultured under stimulated microgravity, illustrating that the activity of COL1A1 promoter might be increased. In conclusion, osteoblasts can compensatively increase the expression of type I collagen by enhancing the activity of COL1A1 promoter under short-term simulated microgravity conditions.     

Molecular prognostic of nine parthanatos death-related genes in glioma,particularly in COL8A1 identification

Post-operative progression and chemotherapy resistance are the main causes of treatment failure in glioma patients. There is a lack of ideal prediction models for post-operative glioma patient progression and drug sensitivity. We aimed to develop a prognostic model of parthanatos mRNA biomarkers for glioma outcomes. A total of 11 parthanatos genes were obtained from ParthanatosCluster database. ConsensusClusterPlus and R “Limma” package were used to cluster The Cancer Genome Atlas (TCGA)-glioma cohort and analyze the differential mRNAs. Univariate Cox regression analysis, random survival forest model, and least absolute shrinkage and selection operator (LASSO) regression analysis were used to determine the nine ParthanatosScore prognostic genes combination. ParthanatosScore was verified by 656 patients and 979 patients in TCGA and CGCA-LGG/GBM datasets. Differences in genomic mutations, tumor microenvironments, and functional pathways were assessed. Drug response prediction was performed using pRRophetic. Kaplan–Meier survival analysis was analyzed. Finally, COL8A1 was selected to evaluate its potential biological function and drug sensitivity of temozolomide and AZD3759 in glioma cells. ParthanatosScore obtained a combination of nine glioma prognostic genes, including CD58, H19, TNFAIP6, FTLP3, TNFRSF11B, SFRP2, LOXL1, COL8A1, and FABP5P7. In the TCGA-LGG/GBM dataset, glioma prognosis was poor in high ParthanatosScore. Low-score glioma patients were sensitive to AZD3759_1915, AZD5582_1617, AZD8186_1918, Dasatinib_1079, and Temozolomide_1375, while high-score patients were less sensitive to these drugs. Compared with HA cells, COL8A1 was significantly over-expressed in LN229 and U251 cells. Silencing COL8A1 inhibited the malignant characterization of LN229 and U251 cells. Temozolomide and AZD3759 also promoted parthanatos gene expression in glioma cells. Temozolomide and AZD3759 inhibited COL8A1 expression and cell viability and promoted apoptosis in glioma cells and PGM cells. ParthanatosScore can accurately predict clinical prognosis and drug sensitivity after glioma surgery. Silencing COL8A1 inhibited the malignant characterization. Temozolomide and AZD3759 inhibited COL8A1 expression and cell viability and promoted apoptosis and parthanatos gene expression, which is a target to improve glioma.     

COL1A1及IGF-1基因与中国北方汉族人群高度近视相关性研究

目的:探讨I型胶原α1链(collagen I alpha-1,COL1A1)基因和类胰岛素生长因子-1 (insulin-like growth factors-1, IGF-1)基因与中国北方汉族人群高度近视的相关性。方法:收集2011年10月~2017年1月经我院眼科视光学中心诊疗的高度近视眼患者286例(病例组)及正常对照者201例(对照组),病例组按照眼球中轴长度分为A组(眼轴长度≥27 mm)126例和B组(眼轴长度27 mm)160例。用血液基因组DNA提取试剂盒提取受试者外周静脉抗凝血中的基因组DNA,采用多重PCR反应和基因测序得到目标片段COL1A1基因的多态位点rs2075555、rs2075554、rs2269336、rs1107946、rs1007086,IGF-1基因的多态位点rs12423791、rs10860860、rs2946834、rs6214的碱基序列,用卡方检验和Logistic回归分析的方法分析病例组和对照组之间各基因分布的差异。结果:病例组和正常对照组COL1A1基因的单核苷酸多态性位点的基因型频率和等位基因频率均无显著性差异(P0.05)。病例组和正常对照组IGF-1基因的rs12423791位点的基因型频率和等位基因频率有统计学差异(P=0.016),其他3个位点的单核苷酸多态性位点均无显著性差异(P0.05)。病例A组和对照组及A组和B组之间COL1A1基因的5个单核苷酸多态性位点分布均无显著性差异(P0.05),IGF-1基因的rs12423791位点有统计学差异(P=0.033)。结论:胶原类基因COL1A1的多态性与中国北方汉族人群高度近视的发生无显著相关性,IGF-1基因的rs12423791位点的多态性与中国北方汉族人群高度近视的发生有显著相关性。     

细胞松弛素D、秋水仙素作用下大鼠肝癌细胞中黏弹性的研究

采用微管吮吸技术测定大鼠肝癌细胞的黏弹性;研究了秋水仙素、细胞松弛素D以及两者混合作用后对于肝癌细胞黏弹性的影响。结果表明:用CD处理癌细胞后发现癌细胞的弹性系数K1明显下降。与对照组相比:微丝骨架被CD抑制后,在加入Col后肝癌细胞的弹性系数K1显著降低;而微管骨架被col抑制后,在加入CD后肝癌细胞的弹性系数K1、K2和μ无明显变化。提示在微管骨架系统完整的情况下,微丝对肝癌细胞的黏弹性系数的的影响起主要作用。而微管骨架系统受到破坏后,微丝需借助于微管网络的作用来影响细胞的黏弹性。本研究对揭示癌细胞中骨架系统之间的交互作用对于细胞黏弹性的影响提高实验依据。     

Effects of clinorotation on COL1A1- EGFP gene expression

Itisnowwellestablishedthatspaceflightin-ducesbonelossafterlong-termexposuretomicro-gravity.Biochemicalstudiesshowedthatcontinuousboneloss[1,2]andmineralredistribution[3]inducedbyspaceflightwereassociatedwiththedecreasedos-teoblasticactivityanddifferentialfunction[4—6].Recentfindingssuggestthechangeintheexpressionofbone-formationrelatedgeneplaysanimportantroleintheprocessofdecreasedosteoblasticfunctionsin-ducedbyspaceflight.CollagentypeIexpressedthroughouttheprocessofosteoblasticproliferationa…