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Non-muscle myosin heavy chain 9-related disease (MYH9-RD) is an autosomal dominant disease caused by the mutations of the MYH9 gene encoding the non-muscle mysoin heavy chain ⅡA and leads to abnormal accumulation of myosin in cells. These further causes functional disorders of the blood, eye, ear, kidney, and liver systems. MYH9-RD displays heterogeneous kidney involvement and outcomes, but doctors still lack understandings of the mechanism and treatment strategies, owing to difficulty of conducting renal biopsies. Here, we report a case of MYH9-RD with tail fragments heterozygous mutation, which renal pathology is presented as glomerular minor lesion. Moreover, we reviewed related relevant to strengthen clinical diagnosis and understanding of MYH9-RD.
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OBJECTIVE@#To investigate the role of myosin heavy chain 9 (MYH9) in regulation of cell proliferation, apoptosis, and cisplatin sensitivity of non-small cell lung cancer (NSCLC).@*METHODS@#Six NSCLC cell lines (A549, H1299, H1975, SPCA1, H322, and H460) and a normal bronchial epithelial cell line (16HBE) were examined for MYH9 expression using Western blotting. Immunohistochemical staining was used to detect MYH9 expression in a tissue microarray containing 49 NSCLC and 43 adjacent tissue specimens. MYH9 knockout cell models were established in H1299 and H1975 cells using CRISPR/Cas9 technology, and the changes in cell proliferation cell were assessed using cell counting kit-8 (CCK8) and clone formation assays; Western blotting and flow cytometry were used to detect apoptosis of the cell models, and cisplatin sensitivity of the cells was evaluated using IC50 assay. The growth of tumor xenografts derived from NSCLC with or without MYH9 knockout was observed in nude mice.@*RESULTS@#MYH9 expression was significantly upregulated in NSCLC (P < 0.001), and the patients with high MYH9 expression had a significantly shorter survival time (P=0.023). In cultured NSCLC cells, MYH9 knockout obviously inhibited cell proliferation (P < 0.001), promoted cell apoptosis (P < 0.05), and increased their chemosensitivity of cisplatin. In the tumor-bearing mouse models, the NSCLC cells with MYH9 knockout showed a significantly lower growth rate (P < 0.05). Western blotting showed that MYH9 knockout inactivated the AKT/c- Myc axis (P < 0.05) to inhibit the expression of BCL2- like protein 1 (P < 0.05), promoted the expression of BH3- interacting domain death agonist and the apoptosis regulator BAX (P < 0.05), and activated apoptosis-related proteins caspase-3 and caspase-9 (P < 0.05).@*CONCLUSION@#High expression of MYH9 contributes to NSCLC progression by inhibiting cell apoptosis via activating the AKT/c-Myc axis.
Subject(s)
Animals , Humans , Mice , Apoptosis , Carcinoma, Non-Small-Cell Lung/metabolism , Cell Line, Tumor , Cell Proliferation , Cisplatin/pharmacology , Cytoskeletal Proteins/metabolism , Lung Neoplasms/metabolism , Mice, Nude , Myosin Heavy Chains/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Signal TransductionABSTRACT
La trombocitopenia como motivo de consulta, requiere la búsqueda intencionada de orientar manifestaciones extrahematológicas. La megacariogénesis pasa por distintas etapas dependientes de la interacción de varios genes, entre ellos el MYH9, cuya expresión permite una adecuada formación y migración de las proplaquetas al ser liberadas al torrente sanguíneo, al mismo tiempo, existen estructuras con fisiología similar a nivel de citoesqueleto (podocitos, cilios cocleares, etc.) que podrían vincular a datos de pérdida de audición, enfermedad renal, cataratas y elevación de enzimas hepáticas conllevando a una enfermedad relacionada al gen MYH9. Se presenta el caso de un adolescente, de sexo masculino, con trombocitopenia recurrente, con el antecedente de padre con coagulopatía inespecífica, pérdida de audición, falla renal crónica, quien falleció a los 34 años por hemorragia intraparenquimatosa y edema cerebral severo, en quien se identifica una variante patogénica en heterocigosis en el gen MYH9, poniendo en relevancia la expresividad variable y efectos pleiotrópicos de este gen.
Thrombocytopenia as a reason for consultation requires an intense search to guide extrahematological manifestations. Megakaryogenesis goes through different stages depending on the interaction of several genes, including MYH9, whose expression allows proper formation and migration of proplatelets when released into the bloodstream, at the same time, there are structures with similar physiology at the cytoskeleton level (podocytes, cochlear cilia, etc.) that could be linked to data on hearing loss, kidney disease, cataracts and elevated liver enzymes leading to a disease related to the MYH9 gene. We present the case of an adolescent, male, with recurrent thrombocytopenia, with a history of a father with nonspecific coagulopathy, hearing loss, chronic kidney failure, who died at the age of 34 due to intraparenchymal hemorrhage and severe cerebral edema, in whom identifies a heterozygous pathogenic variant in the MYH9 gene, highlighting the variable expressivity and pleiotropic effects of this gene.
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ThrombocytopeniaABSTRACT
Objective@#To explore the molecular basis for a pedigree affected with May-Hegglin anomaly (MHA).@*Methods@#Peripheral blood samples were collected and subjected to DNA extraction. Exons 1, 10, 16, 24, 25, 26, 30, 31, 33, 38 and 40 and flanking sequences of the MYH9 gene were subjected to PCR amplification and Sanger sequencing. Changes in protein expression were determined by an indirect immunofluorescence assay. Platelet aggregation function of the proband was assessed by thromboelastogram.@*Results@#The proband and his second son both carried a heterozygous 5521G>A (GAG→AAG) missense variant in exon 38 of the MYH9 gene, leading to p. Glu1841Lys substitution at position 1841 of amino acid sequence. Immunofluorescence showed inclusions containing NMMHC-ⅡA. Thromboelastogram suggested enhanced platelet aggregation function of the proband.@*Conclusion@#The c. 5521G>A variant of MYH9 gene has co-segregated with the phenotype of MHA in this pedigree. To assess the aggregation function of platelet by thromboelastogram can predict the risk of bleeding in MHA patients.
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MYH9-related disorders (MYH9RD) are autosomal-dominant disorders characterized by macrothrombocytopenia with or without leukocyte inclusion bodies or extra-hematological features, such as sensorineural deafness and renal impairment. MYH9RD can be misdiagnosed as an acquired form of thrombocytopenia including immune thrombocytopenic purpura (ITP). This leads to delayed diagnosis or administration of ineffective treatment. In the present study, we investigated the clinical and molecular characteristics of five unrelated Korean patients with MYH9RD and their family members, from four institutions. We reviewed clinical and laboratory data including extra-hematological manifestations. MYH9 pathogenic variants were detected by direct sequencing in all probands and the affected family members (N=10): two probands with c.5521G>A (p.Glu1841Lys) and one proband each with c.99G>T (p.Trp33Cys), c.287C>T (p.Ser96Leu), and c.3493C>T (p.Arg1165Cys). All patients had macrothrombocytopenia. Only the proband with Ser96Leu had extra-hematological manifestations. Past history revealed that two patients had been misdiagnosed with ITP and one of them had received a splenectomy. We validated the frequency of misdiagnosis (~20%) and genotype-phenotype correlations through a comprehensive review of previously reported cases of MYH9RD in Korea. It is important to suspect MYH9RD in patients with thrombocytopenia, and timely identification of macrothrombocytopenia and MYH9 pathogenic variants is required for early and accurate diagnosis of MYH9RD.
Subject(s)
Humans , Deafness , Delayed Diagnosis , Diagnosis , Diagnostic Errors , Genetic Association Studies , Inclusion Bodies , Korea , Leukocytes , Purpura, Thrombocytopenic, Idiopathic , Splenectomy , ThrombocytopeniaABSTRACT
La enfermedad relacionada con MYH9, es un conjunto de síntomas que se expresan por la mutación de la cadena pesada de la miosina no muscular tipo IIA, la cual se expresa ampliamente en las células del cuerpo humano; dicho síndrome es una causa sindrómica de hipoacusia neurosensorial, que cada día ha aumentado su incidencia; y debido a lo anterior y además teniendo en cuenta que este tipo de pérdida auditiva es progresivo y severo, tiene una gran afección sobre la calidad de vida de los pacientes que presentan esta enfermedad, por lo tanto es importante conocer las manifestaciones clínicas relacionadas, la fisiopatología, y el tratamiento de elección en estos casos, con el fin de mejorar la calidad de vida de los pacientes.
MYH9 related disease, is a set of symptoms due to the mutation of the heavy chain of non-muscular myosin type IIA, which is widely expressed in the cells of the human body. It is a syndromic cause of sensorineural hearing loss, which has been increasing its incidence; and taking into account that this type of hearing loss is progressive and severe, its impact on the quality of life of patients is highly important. Therefore it is necessary to know the clinical manifestations related to pathophysiology, and the treatment of choice in these cases, in order to improve the quality of life of patients.
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Humans , Hearing Loss, Sensorineural , Syndrome , Hearing DisordersABSTRACT
Objective To determine the expression of non-muscle myosin heavy chain 9 (MYH9) in osteosarcoma and its effect on the migration and invasion abilities of tumor cell. Methods A total of 65 cases of osteosarcoma and 20 cases with benign osteochondroma who underwent resection operation in the Orthopaedics Department of our hospital from January 1st 2009 to January 1st 2015 were selected. Their mRNA levels of MYH9 were tested by qrt-PCR. Immunohistochemical method was used to examine the expression of MYH9 in osteosarcoma and the correlation between the positive expression of MYH9 and the clinicopathological features of patients was illustrated by statistical analysis. MYH9 was compounded artificially. The expression of MYH9 in SAOS2 osteosarcoma cells was decreased by siRNA. Scratch test was used to determine the change of SAOS2 cell migration ability after MYH9 silence. Transwell assay was employed to detect the change of cell invasion ability after MYH9 silence. Results The expression levels of mRNA of MYH9 and protein in osteosarcoma tissues were significantly higher than those in benign osteochondroma tissues. The high expression of MYH9 in osteosarcoma tissues was apparently related to the high Enneking classification (III classification) and lung metastasis. SiRNA of MYH9 could evidently decrease the expression level of MYH9 in SAOS2. The down-regulated expression of MYH9 could inhibit the migration and invasion abilities of SAOS2 cells. Conclusions MYH9 shows a trend of high expression in osteosarcoma tissues, and its high expression is associated with features such as tumor invasion and metastasis. The down-regulated MYH9 can realize an anti-tumor effect by inhibiting the migration and invasion of osteosarcoma cells.
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OBJECTIVE@#To determine the expression of non-muscle myosin heavy chain 9 (MYH9) in osteosarcoma and its effect on the migration and invasion abilities of tumor cell.@*METHODS@#A total of 65 cases of osteosarcoma and 20 cases with benign osteochondroma who underwent resection operation in the Orthopaedics Department of our hospital from January 1st 2009 to January 1st 2015 were selected. Their mRNA levels of MYH9 were tested by qrt-PCR. Immunohistochemical method was used to examine the expression of MYH9 in osteosarcoma and the correlation between the positive expression of MYH9 and the clinicopathological features of patients was illustrated by statistical analysis. MYH9 was compounded artificially. The expression of MYH9 in SAOS2 osteosarcoma cells was decreased by siRNA. Scratch test was used to determine the change of SAOS2 cell migration ability after MYH9 silence. Transwell assay was employed to detect the change of cell invasion ability after MYH9 silence.@*RESULTS@#The expression levels of mRNA of MYH9 and protein in osteosarcoma tissues were significantly higher than those in benign osteochondroma tissues. The high expression of MYH9 in osteosarcoma tissues was apparently related to the high Enneking classification (III classification) and lung metastasis. SiRNA of MYH9 could evidently decrease the expression level of MYH9 in SAOS2. The down-regulated expression of MYH9 could inhibit the migration and invasion abilities of SAOS2 cells.@*CONCLUSIONS@#MYH9 shows a trend of high expression in osteosarcoma tissues, and its high expression is associated with features such as tumor invasion and metastasis. The down-regulated MYH9 can realize an anti-tumor effect by inhibiting the migration and invasion of osteosarcoma cells.
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May-Hegglin anomaly (MHA) is a myosin-heavy-chain-9 (MYH9)-related disorder characterized by thrombocytopenia with giant platelets and inclusion bodies in leukocytes. MHA does not require treatment, but it may be misdiagnosed as immune thrombocytopenic purpura (ITP) and inappropriately managed. Reported herein is a case of a 12 year old female patient diagnosed as MHA with laboratory findings of severe thrombocytopenia and giant platelets in peripheral blood morphology, and followed up until 23 years of age. The patient had been diagnosed with ITP and treated with intravenous gamma-globulin therapy at another hospital, and showed no improvements in platelet count. She was then referred to our hospital for further diagnostic workup and followed up for 11 years, showing platelet count of 6,000-20,000/µL and prolonged platelet function test. She was occasionally treated with iron therapy due to iron-deficiency anemia. In 2014, we conducted a DNA analysis that revealed c.4339G>T(p.Asp1447Tyr), a known mutation of MYH9 gene.
Subject(s)
Female , Humans , Anemia, Iron-Deficiency , DNA , Follow-Up Studies , gamma-Globulins , Inclusion Bodies , Iron , Leukocytes , Platelet Count , Platelet Function Tests , Purpura, Thrombocytopenic, Idiopathic , ThrombocytopeniaABSTRACT
May-Hegglin anomaly (MHA) is a myosin-heavy-chain-9 (MYH9)-related disorder characterized by thrombocytopenia with giant platelets and inclusion bodies in leukocytes. MHA does not require treatment, but it may be misdiagnosed as immune thrombocytopenic purpura (ITP) and inappropriately managed. Reported herein is a case of a 12 year old female patient diagnosed as MHA with laboratory findings of severe thrombocytopenia and giant platelets in peripheral blood morphology, and followed up until 23 years of age. The patient had been diagnosed with ITP and treated with intravenous gamma-globulin therapy at another hospital, and showed no improvements in platelet count. She was then referred to our hospital for further diagnostic workup and followed up for 11 years, showing platelet count of 6,000-20,000/µL and prolonged platelet function test. She was occasionally treated with iron therapy due to iron-deficiency anemia. In 2014, we conducted a DNA analysis that revealed c.4339G>T(p.Asp1447Tyr), a known mutation of MYH9 gene.
Subject(s)
Female , Humans , Anemia, Iron-Deficiency , DNA , Follow-Up Studies , gamma-Globulins , Inclusion Bodies , Iron , Leukocytes , Platelet Count , Platelet Function Tests , Purpura, Thrombocytopenic, Idiopathic , ThrombocytopeniaABSTRACT
Objective:To explore the associations of MYH9 gene polymorphisms with ESRD in Han population in the fragment between exon 23 and 24.Methods:A hospital-based case control study was carried out including 180 patients and 118 controls in this study.Single nucleotide polymorphisms of MYH9 gene were determined using PCR sequencing,and the haplotypes were calculated using phase software(version 2.0),and transcription factor binding sites were predicted using AliBaba2.Univariate analysis was conducted for exploring the associations between polymorphisms and ESRD.Results: Five newly discovered and three previously reported SNP loci [Rs4821480(MYH9-92),Rs2032487(MYH9-273) and Rs4821481(MYH9-787)]were homozygote genotyped by bidirectional se-quencing.Among newly discovered polymorphisms,two were found at the 489 locus(G→A)and the 616 locus(A→C) in the 901 bp fragment which located in the intron 23 of MYH9 gene.A G489A transversion was very likely a risk mutation contribute to the occurrence of ESRD(P=0.013).No association was observed between ESRD and three previous reported sites [Rs4821480(MYH9-92),Rs2032487(MYH9-273)and Rs4821481(MYH9-787)].The most common haplotype was TCTCGGAT,which was less frequent in the cases than that in the controls.Moreover, TCTCGGCT and TCTCAGAT haplotypes were more in the cases than that in the controls.The number of transcription binding sites increased from 82 ( wild ) to 85 ( mutation ) in the 23th intron of MYH9 gene.Conclusion:Polymorphisms of MYH9 at intron 23 may influence the prevalence of ESRD in Chinese Han population and TCTCGGAT haplotype may be one protective haplotype.TCTCGGCT and TCTCAGAT may be risk haplotypes attributed to ESRD.The polymorphism of MYH9 at the 23th intron may company with the amount alteration of transcription factor binding sites.
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MYH9-related disorder is an autosomal dominant disease caused by a mutation in the MYH9 gene, which encodes nonmuscle myosin heavy chain IIA (NMMHC-IIA). This disease is characterized by giant platelets, thrombocytopenia, granulocyte inclusion bodies, proteinuria, and high-pitch sensorineural deafness. Nephropathy has been observed in 30% of patients with MYH9-related disorder. The characteristic features are early onset proteinuria and rapidly progressing renal disorder. However, the prognosis of MYH9 nephropathy remains unclear. Herein, we describe a 36-year-old woman who presented with proteinuria and was diagnosed with MYH9 nephropathy via renal biopsy and gene analysis. Her proteinuria improved after administration of an angiotensin II receptor blocker, but was aggravated after changing to a calcium channel blocker.
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Adult , Female , Humans , Albuminuria , Biopsy , Calcium Channels , Deafness , Granulocytes , Inclusion Bodies , Myosin Heavy Chains , Prognosis , Proteinuria , Receptors, Angiotensin , ThrombocytopeniaABSTRACT
Objective To explore the association between polymorphisms in non-muscle myosin heavy chain 9 gene (MYH9) and hypertension susceptibility in chronic kidney disease (CKD)patients.Methods Five hundred and ninety-five persons,including 301 patients with CKD and 294 healthy controls,were enrolled in the study.Two single nucleotide polymorphisms (SNPs) (rs3752462,rs4821480) were genotyped by TaqMan assay or a restriction fragment length polymorphism assay for a further case-control study.The discrepancies of the patients'quantitive traits (including age,sex,systolic and diastolic blood pressure,frequency of different primary diseases and using different kinds of antihypertensive drugs) among different genotypes of the two MYH9 SNPs were analyzed.Meanwhile,the association between polymorphisms in MYH9 and hypertension susceptibility in CKD patients were analyzed in the rs3752462 site.Results The systolic blood pressure of CT genotype patients [(147.94± 27.40) mm Hg] was significantly higher than that of C C genotype patients [(136.43 ± 19.09)mm Hg] by single factor analysis of variance (P ＜ 0.05).The frequency of using all kinds of antihypertensive drugs for CC genotype patients (7.4％) was lower than that of TT (43.9％) and CT (48.7％) genotype patients (P ＜ 0.05).After correcting the age factor,the result of Logistic regression analysis showed that CC genotype was a protective factor of systolic blood pressure increasing.The probability of high blood pressure for CT genotype patients with CKD was 0.175 times than that of CC genotype (95％ CI 0.071,0.431).Conclusions The CKD patients who carry the rs3752462 site CC genotype of MYH9 gene are not prone to high blood pressure.Polymorphism of MYH9 gene rs3752462 site is associated with systolic blood pressure in CKD patients.It may indicate that allele C mutation for T can lead to the increase in systolic blood pressure.
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In this report, we describe a Korean patient with May-Hegglin anomaly from a mutation of the MYH9 gene. The proband was a 21-year-old man with thrombocytopenia. He did not have a bleeding tendency. His neutrophil count was normal at 7490/mm3; however, the neutrophils contained abnormal basophilic inclusions in their cytoplasm. The platelet count was decreased at 15000/mm3 with giant platelets. Coagulation test results were not remarkable. Direct sequencing of MYH9 revealed that he was heterozygous for a mutation in exon 1, which was a 97T>A substitution mutation affecting codon 33, substituting tryptophan with arginine (Trp33Arg). Family study showed that both of his parents had normal phenotype and genotypes, indicating a de novo occurrence of the mutation in the proband.
Subject(s)
Adult , Humans , Male , Young Adult , Asian People , Exons/genetics , Molecular Motor Proteins/genetics , Mutation , Myosin Heavy Chains/genetics , Thrombocytopenia/geneticsABSTRACT
May-Hegglin anomaly is an autosomal dominant platelet disorder characterized by giant platelets, thrombocytopenia, and Dohle-like cytoplasmic inclusion bodies in granulocyte. Usually, diagnosis was delayed because they do not have life-threatening bleeding. We experienced a case of May-Hegglin anomaly, which was diagnosed with genetic study at neonate. A 3 days old female has bilateral cephalhematoma at birth after a Caesarean section delivery. Thrombocytopenia with inclusion bodies in granulocyte was observed at peripheral blood cell morphology. Her mother had thrombocytopenia at pregnancy and was diagnosed May-Hegglin anomaly through MYH9 mutation gene study. Accordingly, infant had genetic study and found same gene mutation with mother. Based on the family history, we can diagnose May-Hegglin anomaly in a newborn infant who has cephalhematoma and thrombocytopenia by genetic study.
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Female , Humans , Infant , Infant, Newborn , Pregnancy , Blood Cells , Blood Platelets , Cesarean Section , Granulocytes , Hemorrhage , Inclusion Bodies , Mothers , Parturition , ThrombocytopeniaABSTRACT
Objective To investigate the pathogenesis of renal lesion in Fechtner syndrome . Methods Pathological characteristics of kidney tissues from Fechtner syndrome patients were explored by HE staining, immunochemistry, immunofluorescence and electron microscopy . Results Immunochemistry analysis showed that non-muscle myosin heavy chain IIA (NMMHC-IIA)was expressed in podocytes of giomeruli and distal convoluted tube, and was faintly expressed in the brush border of proximal tube . Histological examination demonstrated glomerulosclerosis and decreased expression of NMMHC-IIA in abnormal podocytes . Through standard immunofluorecence, the expression of NMMHC-IIA in patient's podocyte was higher than that in normal pedocytes . The fusion of foot process and microvillus were detected by electron microscopy . Conclusion Abnormal NMMHC-IIA aggregates in the glomeruli podocyts and foot process fusion accompanied with appearance of microvillus leads to renal lesion in Fechtuer syndrome .
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BACKGROUND: The autosomal dominant giant platelet syndromes (GPS), characterized by triads of giant platelets, thrombocytopenia, and Dohle-like leukocyte inclusions are caused by MYH9 mutation, a gene encoding the nonmuscle myosin heavy chain-IIA. This study was aimed to identify the Korean GPS patients and to define clinical findings and molecular characteristics on them. METHODS: After taking a family history, platelets were counted using hematologic autoanalyzer and peripheral blood smear (PBS) was examined for platelet size and number, and the presence of leukocyte inclusions. Mutation of MYH9 was studied from mononuclear cells from PB by direct sequencing of previously known 8 exons after PCR amplification of genomic DNA. RESULTS: Twenty patients from 5 unrelated families were diagnosed as GPS. Giant platelets, greater than red cells on PBS, were found to be 3.1% of platelet (range, 1~11%). The median platelet count was 61,000/microliter. Inclusion bodies were found in 3 families. Two families had previously reported mutations. Family I had Arg1944Ter in exon 40, located in the tail portion of myosin, while Family IV had Lys373Asn in exon 10, located in the proximal portion of myosin head. The mutations were found only in affected patients, but not in normal siblings or unrelated families. CONCLUSION: In this study, we identified several families with autosomal dominant GPS. Two families had known MYH9 mutations, Arg1944Ter and Lys373Asn. The search for unknown mutations in the remaining families as well as study of protein structural and functional alteration seems to be necessary for further delineation of these rare genetic disorders.
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Humans , Bernard-Soulier Syndrome , Blood Platelets , DNA , Exons , Genes, vif , Head , Inclusion Bodies , Leukocytes , Myosins , Platelet Count , Polymerase Chain Reaction , Siblings , ThrombocytopeniaABSTRACT
The term MYH9-related disorders indicates a group of autosomal dominant illnesses, formerly known as May-Hegglin anomaly, Sebastian syndrome, Fechtner syndrome and Epstein syndrome, caused by mutations of MYH9, the gene encoding for the heavy chain of non-muscle myosin IIA (NMMHC-IIA). We experienced a family with macrothrombocytopenia without leukocyte inclusion. A 5-year-old girl was found to have macrothrombocytopenia incidentally. Her father also had macrothromtocytopenia, but had been suffering from hearing loss and chronic renal failure. Meticulous search by light and electron microscopy failed to detect leukocyte inclusions. To our knowledge, these cases seem to be the first description of autosomal dominant Epstein giant platelet syndrome in Korea.