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Genetics Jan 2024The fibrillinopathies represent a group of diseases in which the 10-12 nm extracellular microfibrils are disrupted by genetic variants in one of the genes encoding... (Review)
Review
The fibrillinopathies represent a group of diseases in which the 10-12 nm extracellular microfibrils are disrupted by genetic variants in one of the genes encoding fibrillin molecules, large glycoproteins of the extracellular matrix. The best-known fibrillinopathy is Marfan syndrome, an autosomal dominant condition affecting the cardiovascular, ocular, skeletal, and other systems, with a prevalence of around 1 in 3,000 across all ethnic groups. It is caused by variants of the FBN1 gene, encoding fibrillin-1, which interacts with elastin to provide strength and elasticity to connective tissues. A number of mouse models have been created in an attempt to replicate the human phenotype, although all have limitations. There are also natural bovine models and engineered models in pig and rabbit. Variants in FBN2 encoding fibrillin-2 cause congenital contractural arachnodactyly and mouse models for this condition have also been produced. In most animals, including birds, reptiles, and amphibians, there is a third fibrillin, fibrillin-3 (FBN3 gene) for which the creation of models has been difficult as the gene is degenerate and nonfunctional in mice and rats. Other eukaryotes such as the nematode C. elegans and zebrafish D. rerio have a gene with some homology to fibrillins and models have been used to discover more about the function of this family of proteins. This review looks at the phenotype, inheritance, and relevance of the various animal models for the different fibrillinopathies.
Topics: Animals; Cattle; Humans; Mice; Rats; Rabbits; Swine; Mutation; Caenorhabditis elegans; Models, Genetic; Zebrafish; Fibrillins
PubMed: 37972149
DOI: 10.1093/genetics/iyad189 -
Journal of Indian Society of... Jul 2010Haim-Munk syndrome is an extremely rare autosomal recessive disorder of keratinization characterized clinically by palmoplantar hyperkeratosis, severe early onset...
Haim-Munk syndrome is an extremely rare autosomal recessive disorder of keratinization characterized clinically by palmoplantar hyperkeratosis, severe early onset periodontitis, onychogryphosis, pes planus, arachnodactyly, and acro-osteolysis. Recently, germline mutations in the lysosomal protease cathepsin C gene have been identified as the underlying genetic defect in Haim-Munk syndrome and in the clinically related disorders, such as Papillon-Lefèvre syndrome and prepubertal periodontitis. The periodontal disease associated with these syndromes is particularly aggressive and unresponsive to traditional periodontal therapies. As a result, most patients become edentulous by 15 years of age. This case report describes a patient with the cardinal features of Haim-Munk syndrome.
PubMed: 21760678
DOI: 10.4103/0972-124X.75919 -
Matrix Biology : Journal of the... 2016The severe skeletal abnormalities associated with Marfan syndrome (MFS) and congenital contractural arachnodactyly (CCA) underscore the notion that fibrillin assemblies... (Review)
Review
The severe skeletal abnormalities associated with Marfan syndrome (MFS) and congenital contractural arachnodactyly (CCA) underscore the notion that fibrillin assemblies (microfibrils and elastic fibers) play a critical role in bone formation and function in spite of representing a low abundance component of skeletal matrices. Studies of MFS and CCA mice have correlated the skeletal phenotypes of these mutant animals with distinct pathophysiological mechanisms that reflect the contextual contribution of fibrillin-1 and -2 scaffolds to TGFβ and BMP signaling during bone patterning, growth and metabolism. Illustrative examples include the unique role of fibrillin-2 in regulating BMP-dependent limb patterning and the distinct impact of the two fibrillin proteins on the commitment and differentiation of marrow mesenchymal stem cells. Collectively, these findings have important implication for our understanding of the pathophysiological mechanisms that drive age- and injury-related processes of bone degeneration.
Topics: Animals; Arachnodactyly; Body Patterning; Cell Differentiation; Contracture; Disease Models, Animal; Fibrillin-1; Fibrillin-2; Humans; Marfan Syndrome; Mesenchymal Stem Cells; Mice; Mutation; Osteogenesis; Signal Transduction; Transforming Growth Factor beta
PubMed: 26408953
DOI: 10.1016/j.matbio.2015.09.004 -
Human Mutation Jul 2022Different pathogenic variants in the fibrillin-1 gene (FBN1) cause Marfan syndrome and acromelic dysplasias. Whereas the musculoskeletal features of Marfan syndrome... (Review)
Review
Different pathogenic variants in the fibrillin-1 gene (FBN1) cause Marfan syndrome and acromelic dysplasias. Whereas the musculoskeletal features of Marfan syndrome involve tall stature, arachnodactyly, joint hypermobility, and muscle hypoplasia, acromelic dysplasia patients present with short stature, brachydactyly, stiff joints, and hypermuscularity. Similarly, pathogenic variants in the fibrillin-2 gene (FBN2) cause either a Marfanoid congenital contractural arachnodactyly or a FBN2-related acromelic dysplasia that most prominently presents with brachydactyly. The phenotypic and molecular resemblances between both the FBN1 and FBN2-related disorders suggest that reciprocal pathomechanistic lessons can be learned. In this review, we provide an updated overview and comparison of the phenotypic and mutational spectra of both the "tall" and "short" fibrillinopathies. The future parallel functional study of both FBN1/2-related disorders will reveal new insights into how pathogenic fibrillin variants differently affect the fibrillin microfibril network and/or growth factor homeostasis in clinically opposite syndromes. This knowledge may eventually be translated into new therapeutic approaches by targeting or modulating the fibrillin microfibril network and/or the signaling pathways under its control.
Topics: Brachydactyly; Fibrillin-1; Fibrillin-2; Humans; Marfan Syndrome; Musculoskeletal Abnormalities; Phenotype
PubMed: 35419902
DOI: 10.1002/humu.24383 -
Hepatology (Baltimore, Md.) Apr 2024Cholangiocarcinoma (CCA) comprises diverse tumors of the biliary tree and is characterized by late diagnosis, short-term survival, and chemoresistance. CCAs are mainly... (Review)
Review
Cholangiocarcinoma (CCA) comprises diverse tumors of the biliary tree and is characterized by late diagnosis, short-term survival, and chemoresistance. CCAs are mainly classified according to their anatomical location and include diverse molecular subclasses harboring inter-tumoral and intratumoral heterogeneity. Besides the tumor cell component, CCA is also characterized by a complex and dynamic tumor microenvironment where tumor cells and stromal cells crosstalk in an intricate network of interactions. Cancer-associated fibroblasts, one of the most abundant cell types in the tumor stroma of CCA, are actively involved in cholangiocarcinogenesis by participating in multiple aspects of the disease including extracellular matrix remodeling, immunomodulation, neo-angiogenesis, and metastasis. Despite their overall tumor-promoting role, recent evidence indicates the presence of transcriptional and functional heterogeneous CAF subtypes with tumor-promoting and tumor-restricting properties. To elucidate the complexity and potentials of cancer-associated fibroblasts as therapeutic targets in CCA, this review will discuss the origin of cancer-associated fibroblasts, their heterogeneity, crosstalk, and role during tumorigenesis, providing an overall picture of the present and future perspectives toward cancer-associated fibroblasts targeting CCA.
Topics: Humans; Cancer-Associated Fibroblasts; Cholangiocarcinoma; Biliary Tract; Bile Duct Neoplasms; Bile Ducts, Intrahepatic; Tumor Microenvironment; Contracture; Arachnodactyly
PubMed: 37018128
DOI: 10.1097/HEP.0000000000000206 -
Journal of Hepatology Feb 2023Cholangiocarcinoma (CCA) is a heterogeneous and lethal malignancy, the molecular origins of which remain poorly understood. MicroRNAs (miRs) target diverse signalling...
BACKGROUND & AIMS
Cholangiocarcinoma (CCA) is a heterogeneous and lethal malignancy, the molecular origins of which remain poorly understood. MicroRNAs (miRs) target diverse signalling pathways, functioning as potent epigenetic regulators of transcriptional output. We aimed to characterise miRNome dysregulation in CCA, including its impact on transcriptome homeostasis and cell behaviour.
METHODS
Small RNA sequencing was performed on 119 resected CCAs, 63 surrounding liver tissues, and 22 normal livers. High-throughput miR mimic screens were performed in three primary human cholangiocyte cultures. Integration of patient transcriptomes and miRseq together with miR screening data identified an oncogenic miR for characterization. MiR-mRNA interactions were investigated by a luciferase assay. MiR-CRISPR knockout cells were generated and phenotypically characterized in vitro (proliferation, migration, colony, mitochondrial function, glycolysis) and in vivo using subcutaneous xenografts.
RESULTS
In total, 13% (140/1,049) of detected miRs were differentially expressed between CCA and surrounding liver tissues, including 135 that were upregulated in tumours. CCA tissues were characterised by higher miRNome heterogeneity and miR biogenesis pathway expression. Unsupervised hierarchical clustering of tumour miRNomes identified three subgroups, including distal CCA-enriched and IDH1 mutant-enriched subgroups. High-throughput screening of miR mimics uncovered 71 miRs that consistently increased proliferation of three primary cholangiocyte models and were upregulated in CCA tissues regardless of anatomical location, among which only miR-27a-3p had consistently increased expression and activity in several cohorts. FoxO signalling was predominantly downregulated by miR-27a-3p in CCA, partially through targeting of FOXO1. MiR-27a knockout increased FOXO1 levels in vitro and in vivo, impeding tumour behaviour and growth.
CONCLUSIONS
The miRNomes of CCA tissues are highly remodelled, impacting transcriptome homeostasis in part through regulation of transcription factors like FOXO1. MiR-27a-3p arises as an oncogenic vulnerability in CCA.
IMPACT AND IMPLICATIONS
Cholangiocarcinogenesis entails extensive cellular reprogramming driven by genetic and non-genetic alterations, but the functional roles of these non-genetic events remain poorly understood. By unveiling global miRNA upregulation in patient tumours and their functional ability to increase proliferation of cholangiocytes, these small non-coding RNAs are implicated as critical non-genetic alterations promoting biliary tumour initiation. These findings identify possible mechanisms for transcriptome rewiring during transformation, with potential implications for patient stratification.
Topics: Humans; Bile Duct Neoplasms; Bile Ducts; Bile Ducts, Intrahepatic; Cholangiocarcinoma; MicroRNAs; Forkhead Box Protein O1
PubMed: 36848245
DOI: 10.1016/j.jhep.2022.10.012 -
Frontiers in Genetics 2021Birt-Hogg-Dubé (BHD) syndrome and congenital contractural arachnodactyly (CCA) or Beals-Hecht syndrome are clinically rare autosomal dominant genetic diseases. In this...
Birt-Hogg-Dubé (BHD) syndrome and congenital contractural arachnodactyly (CCA) or Beals-Hecht syndrome are clinically rare autosomal dominant genetic diseases. In this study, we describe an extremely rare family with BHD syndrome and CCA. To investigate the clinical and genetic characteristics of a family with BHD syndrome and CCA. We describe the clinical characteristics, family history, and clinical manifestations of the patient's family members. The patient underwent a blood test, computed tomography (CT) of the chest, color Doppler ultrasound of the abdomen and heart, and digital radiography of the hands. Whole exome sequencing was performed on his family members. Two years ago, the male proband developed chest tightness and shortness of breath that was accompanied by an irritating cough as well as repeated (four times) spontaneous pneumothorax. The chest CT indicated spontaneous pneumothorax on the right side and cyst and bullae in both lungs. He had no kidney tumors or skin lesions. His son had a history of pulmonary bullae and experienced spontaneous pneumothorax twice. The proband, his mother, and his son were all born with a hand deformity. The sequencing results demonstrated that both the proband and his son had heterozygous variations of the folliculin (FLCN) gene c.1015C > T (p. Gln339Ter) and fibrillin-2 (FBN2) gene c.3485G > A (p. Cys1162Tyr), which are associated with BHD syndrome and CCA, respectively. For patients with chest tightness, shortness of breath, recurrent spontaneous pneumothorax, and congenital hand deformity without inducement, genetic testing should be carried out as soon as possible to make a clear diagnosis, which can then guide treatment and genetic counseling.
PubMed: 35126451
DOI: 10.3389/fgene.2021.768342 -
Archives of Disease in Childhood Aug 1929
PubMed: 21031765
DOI: 10.1136/adc.4.22.190 -
Proceedings of the Royal Society of... Mar 1932
PubMed: 19988640
DOI: No ID Found -
American Journal of Human Genetics Sep 1983Phenotypic, karyotypic, and developmental homology between affected children of carriers of an inverted insertion (9) (q22.1q34.3q34.1) led to recognition of a new...
Phenotypic, karyotypic, and developmental homology between affected children of carriers of an inverted insertion (9) (q22.1q34.3q34.1) led to recognition of a new chromosome syndrome: dup 9q34. Individuals with dup 9q34 have slight psychomotor retardation, understand simple directions, and acquire a limited vocabulary. In childhood, many are hyperactive. Clinical features include low birth weight, normal birth length, and initial poor feeding and thriving. Musculo-skeletal systems are affected: there are joint contractures, long thin limbs, and striking arachnodactyly. There is abnormal implantation of the thumb, increased space between the first and second fingers, and excess digital creases. Marfan syndrome was a provisional diagnosis for several cases prior to cytogenetic analysis. Cardiovascular and ocular systems are minimally affected, erythema and heart murmurs occur, and ptosis and strabismus are frequent, but lens dislocation is not observed. Features at birth include: dolichocephaly, facial asymmetry, narrow horizontal palpebral fissures, microphthalmia, prominent nasal bridge, small mouth, thin upper lip with down-turned corners, and slight retrognathia. In older children, retrognathia is diminished and the nose becomes long and narrow. The new culture and chromosome banding techniques enable sorting of cases with the distal dup 9q phenotype into two groups. The cases with a longer dup 9q are more likely to develop with life-threatening congenital anomalies. The cases with the shorter dup 9q34 have a less severe long-term prognosis and will benefit, together with their parents, from special education. Female carriers of the inv ins(9) (q22.1q34.3q34.1) have about a 31% risk in each pregnancy to conceive a fetus affected by the dup 9q34 syndrome. A comparable figure is not yet available for male carriers.
Topics: Abnormalities, Multiple; Adolescent; Adult; Child; Chromosome Aberrations; Chromosome Banding; Chromosome Inversion; Chromosomes, Human, 6-12 and X; Consanguinity; Female; Heterozygote; Humans; Infant, Newborn; Karyotyping; Male; Middle Aged; Newfoundland and Labrador; Pedigree; Psychomotor Disorders; Risk; Syndrome
PubMed: 6613995
DOI: No ID Found