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Zhou X, Wang J, Mao J, Ye Q. Clinical Manifestations of Alport Syndrome-Diffuse Leiomyomatosis Patients With Contiguous Gene Deletions in COL4A6 and COL4A5. Front Med (Lausanne) 2021; 8:766224. [PMID: 34778325 PMCID: PMC8578185 DOI: 10.3389/fmed.2021.766224] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2021] [Accepted: 09/29/2021] [Indexed: 11/25/2022] Open
Abstract
Alport syndrome-diffuse leiomyomatosis is a rare type of X-linked Alport syndrome resulting from contiguous deletions of 5′ exons of COL4A5 and COL4A6. Studies have suggested that the occurrence of diffuse leiomyomatosis is associated with the characteristic localisation of the COL4A6 gene deletion break point. An electronic database was searched for all studies accessing AS-DL to analyze the clinical characteristics, gene deletion break points of patients with AS-DL, and the pathogenesis of AS-DL. It was found that the proportion of de novo mutations of AS-DL was significantly higher in female probands than male probands (78 vs. 44%). Female patients with AS-DL had a mild clinical presentation. The incidence of proteinuria and ocular abnormalities was much lower in female probands than in male probands, and there was generally no sensorineural hearing loss or chronic kidney disease (CKD), which progressed to Stage 3 in female probands. The contiguous deletion of the 5' exons of COL4A5 and COL4A6, with the break point within the intron 3 of COL4A6, was the critical genetic defect causing AS-DL. However, the pathogenesis of characteristic deletion of COL4A6 that contributes to diffuse leiomyomatosis is still unknown. In addition, characteristic contiguous deletion of COL4A5 and COL4A6 genes in AS-DL may be related to transposed elements (TEs).
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Affiliation(s)
- Xi Zhou
- The Children's Hospital of Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, China
| | - Jingjing Wang
- The Children's Hospital of Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, China
| | - Jianhua Mao
- The Children's Hospital of Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, China
| | - Qing Ye
- The Children's Hospital of Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, China
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2
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Wong T, Pattarapuntakul T, Keeratichananont S, Cattapan K, Nirattisaikul S, Wetwittayakhlung P. Multiple Esophageal Leiomyoma Presenting with Clinical Dysphagia from Mechanical Obstruction and Motility Disorder. Case Rep Gastroenterol 2021; 15:861-868. [PMID: 34720836 PMCID: PMC8543276 DOI: 10.1159/000518861] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Accepted: 07/30/2021] [Indexed: 11/24/2022] Open
Abstract
Esophageal leiomyoma is uncommon. However, this tumor is the most common subepithelial tumor affecting the esophagus, comprising approximately two-thirds of benign esophageal tumors. Leiomyomas of the esophagus rarely cause symptoms when they are single and <5 cm. The mainstay of treatment is esophagectomy for symptomatic patients. A 68-year-old male patient presented with progressive dysphagia for 4 months. The degree of dysphagia and chest discomfort was more severe on solid rather than liquid diet. The CT scan of the chest showed multiple well-defined, submucosal nodules, up to 1.9 cm in diameter located at the middle esophagus. The barium swallow study illustrated multiple, well-defined, smooth, semilunar filling defects along the mid to distal esophagus. Meanwhile, esophagogastroduodenoscopy revealed 8 smooth subepithelial masses. Moreover, the radial EUS showed multiple hypoechoic masses arising from the 4th layer, with some of the tumors connected to others as a horseshoe-like shape causing narrowed lumen. Last, high-resolution esophageal manometry revealed ineffective esophageal motility. We report a rare case of numerous esophageal leiomyomas which caused dysphagia as a result of both mechanical obstruction and hypomotility disorder. The histopathology confirmed the diagnosis of esophageal leiomyoma. Symptoms improved significantly after lifestyle modifications and adherence to dietary advice on the part of the patient.
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Affiliation(s)
- Thanawin Wong
- Division of Gastroenterology and Hepatology, Internal Medicine Department, Songklanagarind hospital, Faculty of Medicine, Prince of Songkla University, Songkhla, Thailand.,NKC Institute of Gastroenterology and Hepatology, Songklanagarind Hospital, Faculty of Medicine, Prince of Songkla University, Songkhla, Thailand
| | - Tanawat Pattarapuntakul
- Division of Gastroenterology and Hepatology, Internal Medicine Department, Songklanagarind hospital, Faculty of Medicine, Prince of Songkla University, Songkhla, Thailand.,NKC Institute of Gastroenterology and Hepatology, Songklanagarind Hospital, Faculty of Medicine, Prince of Songkla University, Songkhla, Thailand
| | - Suriya Keeratichananont
- NKC Institute of Gastroenterology and Hepatology, Songklanagarind Hospital, Faculty of Medicine, Prince of Songkla University, Songkhla, Thailand
| | - Kamonwon Cattapan
- Department of Radiology, Songklanagarind Hospital, Faculty of Medicine, Prince of Songkla University, Songkhla, Thailand
| | - Sitang Nirattisaikul
- Department of Radiology, Songklanagarind Hospital, Faculty of Medicine, Prince of Songkla University, Songkhla, Thailand
| | - Poowadon Wetwittayakhlung
- Department of Anatomical pathology, Faculty of Medicine, Prince of Songkla University, Songkhla, Thailand
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3
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Choi HH, Cho YS, Choi SK, Kim HK, Kim SS, Chae HS, Shin OR. Clinical Outcomes of Endoscopic Removal in Patients with Colorectal Polypoid Leiomyomas. THE KOREAN JOURNAL OF GASTROENTEROLOGY 2017; 68:179-185. [PMID: 27780941 DOI: 10.4166/kjg.2016.68.4.179] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Background/Aims Although polypoid leiomyomas in the colon and rectum are rare, they are increasingly detected during colonoscopy. The aim of this study was to evaluate the efficacy and clinical outcomes of endoscopic removal for colorectal polypoid leiomyoma. Methods Data were retrospectively collected from 22 patients with polypoid leiomyoma arising from the muscularis mucosae in the colon and rectum who underwent endoscopic removal at single referral gastrointestinal endoscopy unit. Colonoscopic findings, endoscopic removal, success rates, complication rates (bleeding or perforation), pathologic characteristics, and recurrence rates were investigated. Results Most polypoid leiomyomas were small asymptomatic lesions less than 1 cm. The tumors were located predominantly in the left colon. Ten leiomyomas were removed using cold biopsy forceps, and 12 were resected by conventional polypectomy or endoscopic mucosal resection. All tumors arose from or involved the muscularis mucosa. There were no complications, such as bleeding or perforation. No local remnant lesions were found in 19 patients who underwent at least one follow-up colonoscopy. Conclusions This case series represent cases of small colorectal polypoid leiomyoma that were safely removed endoscopically. An awareness of their endoscopic and clinic-pathological characteristics may provide safe treatment strategy for colonic leiomyomatous tumors of similar size in capable hands.
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Affiliation(s)
- Hyun Ho Choi
- Department of Internal Medicine, Uijeongbu St. Mary's Hospital, College of Medicine, The Catholic University, Uijeongbu, Korea
| | - Young Seok Cho
- Department of Internal Medicine, Seoul St. Mary's Hospital, College of Medicine, The Catholic University, Seoul, Korea
| | - Soo Kyoung Choi
- Department of Internal Medicine, Uijeongbu St. Mary's Hospital, College of Medicine, The Catholic University, Uijeongbu, Korea
| | - Hyung Keun Kim
- Department of Internal Medicine, Uijeongbu St. Mary's Hospital, College of Medicine, The Catholic University, Uijeongbu, Korea
| | - Sung Soo Kim
- Department of Internal Medicine, Uijeongbu St. Mary's Hospital, College of Medicine, The Catholic University, Uijeongbu, Korea
| | - Hiun Suk Chae
- Department of Internal Medicine, Uijeongbu St. Mary's Hospital, College of Medicine, The Catholic University, Uijeongbu, Korea
| | - Ok Ran Shin
- Department of Hospital Pathology, Uijeongbu St. Mary's Hospital, College of Medicine, The Catholic University, Uijeongbu, Korea
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4
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Characterization of contiguous gene deletions in COL4A6 and COL4A5 in Alport syndrome-diffuse leiomyomatosis. J Hum Genet 2017; 62:733-735. [PMID: 28275241 DOI: 10.1038/jhg.2017.28] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2017] [Revised: 01/31/2017] [Accepted: 01/31/2017] [Indexed: 11/08/2022]
Abstract
Alport syndrome-diffuse leiomyomatosis (AS-DL, OMIM: 308940) is a rare variant of the X-linked Alport syndrome that shows overgrowth of visceral smooth muscles in the gastrointestinal, respiratory and female reproductive tracts in addition to renal symptoms. AS-DL results from deletions that encompass the 5' ends of the COL4A5 and COL4A6 genes, but deletion breakpoints between COL4A5 and COL4A6 have been determined in only four cases. Here, we characterize deletion breakpoints in five AS-DL patients and show a contiguous COL4A6/COL4A5 deletion in each case. We also demonstrate that eight out of nine deletion alleles involved sequences homologous between COL4A5 and COL4A6. Most breakpoints took place in recognizable transposed elements, including long and short interspersed repeats, DNA transposons and long-terminal repeat retrotransposons. Because deletions involved the bidirectional promoter region in each case, we suggest that the occurrence of leiomyomatosis in AS-DL requires inactivation of both genes. Altogether, our study highlights the importance of homologous recombination involving multiple transposed elements for the development of this continuous gene syndrome and other atypical loss-of-function phenotypes.
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Liu W, Wong JKL, He Q, Wong EHM, Tang CSM, Zhang R, So MT, Wong KKY, Nicholls J, Cherny SS, Sham PC, Tam PK, Garcia-Barcelo MM, Xia H. Chinese family with diffuse oesophageal leiomyomatosis: a new COL4A5/COL4A6 deletion and a case of gonosomal mosaicism. BMC MEDICAL GENETICS 2015; 16:49. [PMID: 26179878 PMCID: PMC4557859 DOI: 10.1186/s12881-015-0189-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/17/2014] [Accepted: 06/15/2015] [Indexed: 12/16/2022]
Abstract
BACKGROUND Diffuse oesophageal leiomyomatosis (DOL) is a rare disorder characterized by tumorous overgrowth of the muscular wall of the oesophagus. DOL is present in 5 % of Alport syndrome (AS) patients. AS is a rare hereditary disease that involves varying degrees of hearing impairment, ocular changes and progressive glomerulonephritis leading to renal failure. In DOL-AS patients, the genetic defect consists of a deletion involving the COL4A5 and COL4A6 genes on the X chromosome. CASE PRESENTATION We report a two-generation family (4 individuals; parents and two children, one male and one female) with two members (mother and son) affected with oesophageal leiomyomatosis. Signs of potential renal failure, which characterizes AS, were only apparent in the index patient (son) 2 years and three months after the initial diagnosis of DOL. Blood DNA from the four family members were submitted to exome sequencing and array genotyping to perform a genome wide screening for disease causal single nucleotide (SN) and copy number (CN) variations. Analyses revealed a new 40kb deletion encompassing from intron 2 of COL4A5 to intron 1 of COL4A6 at Xq22.3. The breakpoints were also identified. Possible confounding pathogenic exonic variants in genes known to be involved in other extracellular matrices disorders were also shared by the two affected individuals. Meticulous analysis of the maternal DNA revealed a case of gonosomal mosaicism. CONCLUSIONS This is the first report of gonadosomal mosaicism associated to DOL-AS.
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Affiliation(s)
- Wei Liu
- Department of Pediatric Surgery, Guangzhou Women and Children's Medical Center, Guangzhou, China.
| | - John K L Wong
- Department of Psychiatry, The University of Hongkong, Hongkong, SAR, China.
| | - Qiuming He
- Department of Pediatric Surgery, Guangzhou Women and Children's Medical Center, Guangzhou, China.
| | - Emily H M Wong
- Department of Psychiatry, The University of Hongkong, Hongkong, SAR, China.
| | - Clara S M Tang
- Department of Psychiatry, The University of Hongkong, Hongkong, SAR, China. .,Department of Surgery, The University of Hongkong, Hongkong, SAR, China.
| | - Ruizhong Zhang
- Department of Surgery, The University of Hongkong, Hongkong, SAR, China.
| | - Man-Ting So
- Department of Surgery, The University of Hongkong, Hongkong, SAR, China.
| | - Kenneth K Y Wong
- Department of Surgery, The University of Hongkong, Hongkong, SAR, China.
| | - John Nicholls
- Department of Pathology, The University of Hongkong, Hongkong, SAR, China.
| | - Stacey S Cherny
- Department of Psychiatry, The University of Hongkong, Hongkong, SAR, China. .,Center for Genomic Sciences, The University of Hongkong, Hongkong, SAR, China.
| | - Pak C Sham
- Department of Psychiatry, The University of Hongkong, Hongkong, SAR, China. .,Center for Genomic Sciences, The University of Hongkong, Hongkong, SAR, China. .,Centre for Reproduction, Development, and Growth of the Li Ka Shing Faculty of Medicine, Hong Kong, SAR, China. .,State Key Laboratory of Brain and Cognitive Sciences, The University of Hong Kong, Hong Kong, SAR, China.
| | - Paul K Tam
- Department of Surgery, The University of Hongkong, Hongkong, SAR, China. .,Center for Genomic Sciences, The University of Hongkong, Hongkong, SAR, China. .,Centre for Reproduction, Development, and Growth of the Li Ka Shing Faculty of Medicine, Hong Kong, SAR, China. .,State Key Laboratory of Brain and Cognitive Sciences, The University of Hong Kong, Hong Kong, SAR, China.
| | - Maria-Mercè Garcia-Barcelo
- Department of Surgery, The University of Hongkong, Hongkong, SAR, China. .,Center for Genomic Sciences, The University of Hongkong, Hongkong, SAR, China. .,Centre for Reproduction, Development, and Growth of the Li Ka Shing Faculty of Medicine, Hong Kong, SAR, China. .,State Key Laboratory of Brain and Cognitive Sciences, The University of Hong Kong, Hong Kong, SAR, China.
| | - Huimin Xia
- Department of Pediatric Surgery, Guangzhou Women and Children's Medical Center, Guangzhou, China.
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Smooth muscle tumors of soft tissue and non-uterine viscera: biology and prognosis. Mod Pathol 2014; 27 Suppl 1:S17-29. [PMID: 24384850 PMCID: PMC7662208 DOI: 10.1038/modpathol.2013.178] [Citation(s) in RCA: 63] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2013] [Revised: 06/27/2013] [Accepted: 06/27/2013] [Indexed: 12/20/2022]
Abstract
Smooth muscle tumors are here considered an essentially dichotomous group composed of benign leiomyomas and malignant leiomyosarcomas. Soft tissue smooth muscle tumors with both atypia and mitotic activity are generally diagnosed leiomyosarcomas acknowledging potential for metastasis. However, lesions exist that cannot be comfortably placed in either category, and in such cases the designation 'smooth muscle tumor of uncertain biologic potential' is appropriate. The use of this category is often necessary with limited sampling, such as needle core biopsies. Benign smooth muscle tumors include smooth muscle hamartoma and angioleiomyoma. A specific category of leiomyomas are estrogen-receptor positive ones in women. These are similar to uterine leiomyomas and can occur anywhere in the abdomen and abdominal wall. Leiomyosarcomas can occur at any site, although are more frequent in the retroperitoneum and proximal extremities. They are recognized by likeness to smooth muscle cells but can undergo pleomorphic evolution ('dedifferentiation'). Presence of smooth muscle actin is nearly uniform and desmin-positivity usual. This and the lack of KIT expression separate leiomyosarcoma from GIST, an important problem in abdominal soft tissues. EBV-associated smooth muscle tumors are a specific subcategory occurring in AIDS or post-transplant patients. These tumors can have incomplete smooth muscle differentiation but show nuclear EBER as a diagnostic feature. In contrast to many other soft tissue tumors, genetics of smooth muscle tumors are poorly understood and such diagnostic testing is not yet generally applicable in this histogenetic group. Leiomyosarcomas are known to be genetically complex, often showing 'chaotic' karyotypes including aneuploidy or polyploidy, and no recurrent tumor-specific translocations have been detected.
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Sá MJN, Fieremans N, de Brouwer APM, Sousa R, Costa FTE, Brito MJ, Carvalho F, Rodrigues M, de Sousa FT, Felgueiras J, Neves F, Carvalho A, Ramos U, Vizcaíno JR, Alves S, Carvalho F, Froyen G, Oliveira JP. Deletion of the 5′exons ofCOL4A6is not needed for the development of diffuse leiomyomatosis in patients with Alport syndrome. J Med Genet 2013; 50:745-53. [DOI: 10.1136/jmedgenet-2013-101670] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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Abstract
Neoplasms of striated and smooth muscle in children are a diverse group of neoplasms that have some unique aspects in contrast to these tumors in adults. Rhabdomyosarcoma is the most common soft tissue sarcoma of infancy and childhood and is relatively common in adolescents. In contrast, smooth muscle tumors are relatively rare, and the various types of rhabdomyoma and smooth and skeletal muscle hamartomas are very uncommon. In recent years, the understanding of the pathologic and genetic aspects of rhabdomyosarcoma has been enhanced by adjunct techniques, such as immunohistochemistry and cytogenetic or molecular genetic analysis. The current classification of rhabdomyosarcoma emphasizes the histologic-prognostic correlations. This article reviews the clinicopathologic features of striated and smooth muscle tumors with an emphasis on the unique aspects of these neoplasms in children and adolescents and the differential diagnosis.
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Affiliation(s)
- David M Parham
- Department of Pathology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA.
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9
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Alport syndrome and leiomyomatosis: the first deletion extending beyond COL4A6 intron 2. Pediatr Nephrol 2011; 26:717-24. [PMID: 21380622 DOI: 10.1007/s00467-010-1693-9] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/09/2009] [Revised: 09/20/2010] [Accepted: 09/23/2010] [Indexed: 10/18/2022]
Abstract
Alport syndrome (ATS) is a nephropathy characterized by the association of progressive hematuric nephritis with ultrastructural changes of the glomerular basement membrane (thinning, thickening, and splitting), sensorineural deafness, and variable ocular abnormalities (anterior lenticonus, macular flecks, and cataracts). The most common mode of transmission is X-linked inheritance, due to COL4A5 mutations. X-linked ATS is rarely associated with diffuse leiomyomatosis (DL), a benign hypertrophy of the visceral smooth muscle in gastrointestinal, respiratory, and female reproductive tracts. The ATS-DL complex is due to deletions that encompass the 5' ends of the COL4A5 and COL4A6 genes and include the bidirectional promoter. In this paper, we described 3 ATS-DL cases, 2 familial and 1 sporadic bearing a deletion encompassing the 5'-end of both the COL4A5 and COL4A6 genes, as identified by multiplex ligation-dependent probe amplification (MLPA) analysis. The array-CGH technique allowed a better definition of deletion size, confirming that the proximal breakpoint was within COL4A6 intron 2 in 2 cases. Surprisingly, 1 case had a deletion extending proximally beyond exon 3 of COL4A6, as confirmed by qPCR analysis. This is the largest deletion reported to date that has been associated with ATS-DL and this case should lead us to reconsider the mechanisms that might be involved in the development of diffuse leiomyomatosis.
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10
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Saito K, Yonezawa T, Minaguchi J, Kurosaki M, Suetsugu S, Nakajima A, Nomoto H, Morizane Y, Sado Y, Sugimoto M, Kusachi S, Ninomiya Y. Distribution of α(IV) collagen chains in the ocular anterior segments of adult mice. Connect Tissue Res 2011; 52:147-56. [PMID: 20672978 DOI: 10.3109/03008207.2010.492062] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The distribution of the collagen chains from α1(IV) to α6(IV) could serve as a basis for the characterization of type IV collagen. In this study, immunohistochemistry of the ocular anterior segment of adult mice was performed using specific monoclonal antibodies against each chain in the series from α1(IV) to α6(IV). The results show that the components of type IV collagen in vascular basement membranes are α1(IV) and α2(IV) with or without α5(IV) and α6(IV) chains and those in epithelium and muscle basement membranes are α1(IV), α2(IV), α5(IV), and α6(IV) chains. In corneal endothelium, pigmented epithelium of iris and ciliary body, and trabecular meshwork, α3(IV) and α4(IV) chains are also expressed in addition to α1(IV), α2(IV), α5(IV), and α6(IV) chains. Moreover, we investigated the change in molecular composition in ciliary body during postnatal development. α3(IV) and α4(IV) chains were also expressed in addition to α1(IV), α2(IV), α5(IV), and α6(IV) chains in ciliary pigmented epithelium basement membrane from 7 days after birth. This result suggests that the basement membranes gradually change their biochemical features owing to temporal regulation. Taken together, these findings suggest that the different distribution and the developmental expression of α1(IV) to α6(IV) chains are associated with the tissue-specific function of type IV collagen in basement membranes.
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Affiliation(s)
- Kenji Saito
- Department of Molecular Biology and Biochemistry, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Kita-ku, Okayama, Japan
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Oohashi T, Naito I, Ueki Y, Yamatsuji T, Permpoon R, Tanaka N, Naomoto Y, Ninomiya Y. Clonal overgrowth of esophageal smooth muscle cells in diffuse leiomyomatosis-Alport syndrome caused by partial deletion in COL4A5 and COL4A6 genes. Matrix Biol 2010; 30:3-8. [PMID: 20951201 DOI: 10.1016/j.matbio.2010.09.003] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2010] [Revised: 09/24/2010] [Accepted: 09/24/2010] [Indexed: 10/18/2022]
Abstract
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.
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Affiliation(s)
- Toshitaka Oohashi
- Department of Molecular Biology and Biochemistry, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Kita-ku, Okayama, Japan
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12
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Anesthetic management of a patient with Alport-leiomyomatosis syndrome. J Anesth 2009; 23:453-5. [PMID: 19685135 DOI: 10.1007/s00540-009-0749-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2008] [Accepted: 02/04/2008] [Indexed: 11/27/2022]
Abstract
We report the anesthetic management of esophagectomy for a patient with Alport-leiomyomatosis syndrome. A 23-year-old woman complained of dysphagia and severe chest pain. Her chest X-ray, computed tomography (CT), and magnetic resonance imaging (MRI) showed an enlarged esophagus, in contact with the trachea, heart, aorta, and large vessels. She frequently experienced severe asthma attacks. Because various risks in both respiration and circulation, especially in anesthesia induction, were of concern, her right femoral vessels were exposed, for the emergency use of percutaneous cardiopulmonary support (PCPS), prior to anesthesia induction. Anesthesia was induced and maintained with propofol, fentanyl, and vecuronium. Esophagectomy was performed uneventfully and no severe events were seen in anesthesia management. Alportleiomyomatosis syndrome is a very rare disease. When we are involved in the anesthetic management of a patient with this disease, evaluation of the influence of the enlarged esophagus on both respiration and circulation, and careful preparation for emergence, are very important.
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Abstract
Leiomyomas are rare esophageal disorders, although among the benign esophageal neoplasms, they are the most common. Multiple leiomyomas are distinguished from esophageal leiomyomatosis, an extremely rare condition, which is associated with Alport syndrome, showing deletions and rearrangements of the COL4A5/COL4A6 gene. There are only a few reports of diffuse multilocular lesions. A 19-year-old man presented with upper gastrointestinal bleeding and diffuse abdominal pain. On endoscopy multiple nodules covered with intact mucosa were present, the largest tumor arising from the gastro-esophageal border infiltrating the cardia. Barium swallow demonstrated narrowing of the middle and lower esophagus with the upper third of the stomach filled by the tumor. Thorax and abdominal CT scans revealed infiltration of almost the total aboral esophagus by the tumor with compression of left and right bronchi. The infiltration reached the whole lesser curvature of the stomach. Endosonography showed multiple encapsulated nodules. Due to the extended tumor growth with infiltration of the upper third of the stomach, a total esophago-gastrectomy with reconstruction by colon interposition was performed. On histopathological examination multiple esophageal leiomyomas with infiltration of the proximal third of the stomach was shown. Immunohistochemically the tumor stained positive for desmin and sm-actin and negative for CD34 and c-kit. Genetic analysis ruled out a deletion of the COL4A5/COL4A6 locus on chromosome X that is linked with Alport syndrome-diffuse leiomyomatosis. Extended mutations in the COL4A5 gene, associated with Alport syndrome, to the COL4A6 gene, are required for the development of leiomyomatosis. In young patients with diffuse multinodular infiltration by encapsulated tumors, esophageal leiomyomatosis should be considered. If the proximal third of the stomach is infiltrated by the tumor an extended resection is necessary. Reconstruction procedures include colon interposition.
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Affiliation(s)
- K L Prenzel
- Department of Visceral and Vascular Surgery, University of Cologne, Cologne, Germany.
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14
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Yagasaki H, Hamanoue S, Oda T, Nakahata T, Asano S, Yamashita T. Identification and characterization of novel mutations of the major Fanconi anemia gene FANCA in the Japanese population. Hum Mutat 2005; 24:481-90. [PMID: 15523645 DOI: 10.1002/humu.20099] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Fanconi anemia (FA) is a rare autosomal recessive disorder of hematopoiesis, with at least 11 complementation groups. FANCA, a gene for group A, accounts for the majority of FA patients. Previous studies of FANCA mutations revealed high allelic heterogeneity, frequent occurrence of large deletions, and interpopulation differences. However, systematic mutational analysis, including gene dosage assay to detect large deletions, has not been documented for Asian populations. A newly developed TaqMan quantitative PCR-based gene dosage assay, combined with sequencing of exons and cDNA fragments, allowed for detection of 48 mutant alleles of FANCA in 27 (77%) of 35 unrelated Japanese FA families with no detectable mutations in FANCC or FANCG. We identified 29 different mutations (21 nucleotide substitutions or small deletions/insertions and eight large deletions), at least 20 of which were novel. The FANCA mutational spectrum of the Japanese was different from that of other ethnic groups so far studied. This is the largest scale of mutation analysis of FANCA in the Japanese population. Characterization of these mutations provided new information regarding the mutagenesis mechanisms and structure-function relationship of FANCA. Specifically, our data suggest that diverse mechanisms including nonhomologous recombination as well as Alu-mediated homologous recombination are involved in the generation of large deletions in FANCA.
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Affiliation(s)
- Hiroshi Yagasaki
- Division of Genetic Diagnosis, The Institute of Medical Science, The University of Tokyo, Tokyo, Japan
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Sandberg AA. Updates on the cytogenetics and molecular genetics of bone and soft tissue tumors: leiomyoma. ACTA ACUST UNITED AC 2005; 158:1-26. [PMID: 15771900 DOI: 10.1016/j.cancergencyto.2004.08.025] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2004] [Revised: 08/11/2004] [Accepted: 08/11/2004] [Indexed: 12/22/2022]
Affiliation(s)
- Avery A Sandberg
- Department of DNA Diagnostics, St. Joseph's Hospital and Medical Center, 350 West Thomas Road, Phoenix, AZ 85013, USA.
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16
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Abeysinghe SS, Chuzhanova N, Krawczak M, Ball EV, Cooper DN. Translocation and gross deletion breakpoints in human inherited disease and cancer I: Nucleotide composition and recombination-associated motifs. Hum Mutat 2003; 22:229-44. [PMID: 12938088 DOI: 10.1002/humu.10254] [Citation(s) in RCA: 187] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Translocations and gross deletions are important causes of both cancer and inherited disease. Such gene rearrangements are nonrandomly distributed in the human genome as a consequence of selection for growth advantage and/or the inherent potential of some DNA sequences to be frequently involved in breakage and recombination. Using the Gross Rearrangement Breakpoint Database [GRaBD; www.uwcm.ac.uk/uwcm/mg/grabd/grabd.html] (containing 397 germ-line and somatic DNA breakpoint junction sequences derived from 219 different rearrangements underlying human inherited disease and cancer), we have analyzed the sequence context of translocation and deletion breakpoints in a search for general characteristics that might have rendered these sequences prone to rearrangement. The oligonucleotide composition of breakpoint junctions and a set of reference sequences, matched for length and genomic location, were compared with respect to their nucleotide composition. Deletion breakpoints were found to be AT-rich whereas by comparison, translocation breakpoints were GC-rich. Alternating purine-pyrimidine sequences were found to be significantly over-represented in the vicinity of deletion breakpoints while polypyrimidine tracts were over-represented at translocation breakpoints. A number of recombination-associated motifs were found to be over-represented at translocation breakpoints (including DNA polymerase pause sites/frameshift hotspots, immunoglobulin heavy chain class switch sites, heptamer/nonamer V(D)J recombination signal sequences, translin binding sites, and the chi element) but, with the exception of the translin-binding site and immunoglobulin heavy chain class switch sites, none of these motifs were over-represented at deletion breakpoints. Alu sequences were found to span both breakpoints in seven cases of gross deletion that may thus be inferred to have arisen by homologous recombination. Our results are therefore consistent with a role for homologous unequal recombination in deletion mutagenesis and a role for nonhomologous recombination in the generation of translocations.
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Affiliation(s)
- Shaun S Abeysinghe
- Institute of Medical Genetics, University of Wales College of Medicine, Cardiff, UK
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17
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Anker MC, Arnemann J, Neumann K, Ahrens P, Schmidt H, König R. Alport syndrome with diffuse leiomyomatosis. Am J Med Genet A 2003; 119A:381-5. [PMID: 12784310 DOI: 10.1002/ajmg.a.20019] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Alport syndrome (AS) is a hereditary nephropathy with hematuria progressing to end-stage renal failure (ESRF), sensorineural deafness, and specific eye signs (lenticonus, macular flecks, and congenital cataracts). Inheritance is X-linked in about 85% of the cases, caused by different mutations in the COL4A5 gene. Rarely AS is seen in combination with diffuse leiomyomatosis (DL). DL is a tumorous process involving smooth muscle cells, mostly of the esophagus, but also of the tracheobronchial tree and the female genital tract. Characteristically, the patients have deletions of the 5'-end of both the COL4A5 and the COL4A6 genes, respectively. We here present a 9-year-old boy who was admitted because of a newly diagnosed sensorineural deafness. He was born with cataracts and presented symptoms of dysphagia and bronchial irritation in the first year of life. Macroscopic hematuria was first noticed at 2 years during a febrile infection. Since early childhood the boy suffered from severe constipation. Taking together these symptoms, the diagnosis of Alport syndrome with diffuse leiomyomatosis (AS-DL) has to be considered. Genetic analysis demonstrated the predicted deletion of the COL4A5/COL4A6 genes.
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Affiliation(s)
- Martina C Anker
- Institute of Human Genetics, Johann Wolfgang Goethe University Hospital, Frankfurt, Germany
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18
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Martinez-Mir A, Gordon D, Horev L, Klapholz L, Ott J, Christiano AM, Zlotogorski A. Multiple cutaneous and uterine leiomyomas: refinement of the genetic locus for multiple cutaneous and uterine leiomyomas on chromosome 1q42.3-43. J Invest Dermatol 2002; 118:876-80. [PMID: 11982768 DOI: 10.1046/j.1523-1747.2002.01741.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Cutaneous leiomyomas, rare benign tumors originating from the arrector pili muscle of the hair follicle, can be associated with the common uterine fibroids in a syndrome called multiple cutaneous and uterine leiomyomas. Multiple cutaneous and uterine leiomyomas are inherited as an autosomal dominant trait, providing an excellent opportunity for the study of the common non-Mendelian manifestation of isolated uterine fibroids. This study reports the clinical and molecular characterization of an extended family with multiple cutaneous and uterine leiomyomas. Linkage analysis has shown that the disease in this family is linked to the recently reported genetic locus for multiple cutaneous and uterine leiomyomas, with a maximum two-point LOD score of 4.453 for markers D1S2670, D1S2785, D1S547, and D1S1609. The identification of key recombination events has allowed us to refine substantially the location of the genetic locus for multiple cutaneous and uterine leiomyomas, from 14 cM to an interval of 4.55 or 7.19 cM, depending on the final phenotype of a young family member in which one of the key recombination events has occurred. In addition, we provide a description of the interesting pattern and progression of the skin phenotype in this four-generation kindred. The refinement of the genetic locus for multiple cutaneous and uterine leiomyomas and the availability of an extended multigeneration pedigree will facilitate the identification of the mutated gene responsible for multiple cutaneous and uterine leiomyomas, which, in turn, may provide key information for the understanding of the molecular basis of the common uterine fibroids.
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19
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Calabrese C, Fabbri A, Fusaroli P, Di Gaetano P, Miglioli M, Di Febo G. Diffuse esophageal leiomyomatosis: case report and review. Gastrointest Endosc 2002; 55:590-3. [PMID: 11923782 DOI: 10.1067/mge.2002.122581] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/10/2022]
Affiliation(s)
- Carlo Calabrese
- Department of Internal Medicine and Gastroenterology, University of Bologna, Bologna, Italy
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20
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Mothes H, Heidet L, Arrondel C, Richter KK, Thiele M, Patzer L, Sado Y, Gubler MC, Antignac C, Scheele J. Alport syndrome associated with diffuse leiomyomatosis: COL4A5-COL4A6 deletion associated with a mild form of Alport nephropathy. Nephrol Dial Transplant 2002; 17:70-4. [PMID: 11773466 DOI: 10.1093/ndt/17.1.70] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND The X-linked Alport syndrome (AS) is an inherited nephropathy due to mutations in the COL4A5 gene, encoding the alpha5 chain of type IV collagen, a major component of the glomerular basement membrane (GBM). Here, we report a new kindred with the rare association of X-linked AS and diffuse leiomyomatosis (DL), which is a tumourous process involving smooth muscle cells of the oesophagus, the tracheobronchial tree and, in females, the genital tract. For this syndrome, an almost constant association of large COL4A5 rearrangements with a severe juvenile form of nephropathy has been described for male patients. METHODS DNA rearrangement at the COL4A5-COL4A6 locus was studied in several members of this family using polymerase chain reaction and pulsed field gel electrophoresis. Furthermore, immunohistochemical staining of tumour and skin samples was performed. RESULTS The affected patients in this family carry a 120 kb deletion by which the COL4A5 exon 1 and COL4A6 exons 1, 1', and 2 are removed. Immunohistochemical investigation of a skin biopsy of an affected male patient confirmed the absence of both the alpha5 and the alpha6 chains of type IV collagen in the basement membrane of the skin. Surprisingly, both affected male patients had a rather mild renal phenotype. CONCLUSIONS This report shows that, contrary to what has been reported to date, patients suffering from AS associated with DL can be associated with a late onset renal failure (adult) form of nephropathy.
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Affiliation(s)
- Henning Mothes
- Department of General and Visceral Surgery, Friedrich-Schiller-University Jena, Bachstrasse 18, D-07740 Jena, Germany.
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21
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Williams M, Rainville IR, Nicklas JA. Use of inverse PCR to amplify and sequence breakpoints of HPRT deletion and translocation mutations. ENVIRONMENTAL AND MOLECULAR MUTAGENESIS 2002; 39:22-32. [PMID: 11813293 DOI: 10.1002/em.10040] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Deletion and translocation mutations have been shown to play a significant role in the genesis of many cancers. The hprt gene located at Xq26 is a frequently used marker gene in human mutational studies. In an attempt to better understand potential mutational mechanisms involved in deletions and translocations, inverse PCR (IPCR) methods to amplify and sequence the breakpoints of hprt mutants classified as translocations and large deletions were developed. IPCR involves the digestion of DNA with a restriction enzyme, circularization of the fragments produced, and PCR amplification around the circle with primers oriented in a direction opposite to that of conventional PCR. The use of this technique allows amplification into an unknown region, in this case through the hprt breakpoint into the unknown joined sequence. Through the use of this procedure, two translocation, one inversion, and two external deletion hprt breakpoint sequences were isolated and sequenced. The isolated IPCR products range in size from 0.4 to 1.8 kb, and were amplified from circles ranging in size from 0.6 to 7.7 kb. We have shown that inverse PCR is useful to sequence translocation and large deletion mutant breakpoints in the hprt gene.
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Affiliation(s)
- M Williams
- Graduate Program in Cellular and Molecular Biology, University of Michigan, Ann Arbor, Michigan, USA
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22
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Miettinen M, Sarlomo-Rikala M, Sobin LH. Mesenchymal tumors of muscularis mucosae of colon and rectum are benign leiomyomas that should be separated from gastrointestinal stromal tumors--a clinicopathologic and immunohistochemical study of eighty-eight cases. Mod Pathol 2001; 14:950-6. [PMID: 11598163 DOI: 10.1038/modpathol.3880417] [Citation(s) in RCA: 81] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Most mesenchymal tumors of the gastrointestinal tract are currently classified as specific gastrointestinal stromal tumors. However, true leiomyomas are more common in the esophagus, and they have been occasionally noted in the colon and rectum, but the small number of reported cases does not allow for clinicopathologic profiling. This study was undertaken to characterize 88 tumors of the muscularis mucosae of the colon and rectum. Seventy tumors were obtained form the files of AFIP and 18 cases from the Department of Pathology of the Haartman Institute of the University of Helsinki. The lesions, except one, were removed by snare polypectomy as incidental lesions at cancer or polyp surveillance; one small tumor was an incidental finding in the rectal resection specimen. The tumors had a significant male predominance in both institutions (overall 2.4:1). They occurred in age range of 38 to 85 years (median 62 years). The lesions were typically small (range 1 to 22 mM, median 4 mM) and located predominantly in the rectum and sigmoid (72%). All tumors were composed of well-differentiated, eosinophilic smooth muscle cells that were seen immediately beneath the mucosa obliterating the muscularis mucosae layer and merging with it. Two tumors had significant atypia ("symplastic leiomyoma"); mitotic activity was seen in one of these tumors, but not in others. The lesional cells were uniformly positive for smooth muscle actin and desmin and negative for CD34, CD117 and S100-protein, based on immunohistochemical studies on 20 to 24 cases with each marker. No gastrointestinal stromal tumors were identified among the tumors of muscularis mucosae, and no CD117-positive cells, except mast cells, were seen in the muscularis mucosae layer. None of the patients had morbidity related to the tumor. Based on follow-up data on 29 patients, leiomyomas of muscularis mucosae are benign. They should be separated from gastrointestinal stromal tumors that have a clinicopathologic spectrum including frequent disease-related mortality. Snare polypectomy is an adequate treatment, but ensuring the complete removal and follow-up are necessary precautions for tumors with any atypia or mitotic activity.
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Affiliation(s)
- M Miettinen
- Department of Soft Tissue Pathology, Armed Forces Institute of Pathology, Washington, DC 20306-6000, USA
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23
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Abstract
BACKGROUND Leiomyomas are rare esophagus neoplasms. They are usually solitary, and the diffuse lesion is extremely rare. CASE REPORT A 19-year-old male presented with a 3-year history of occasional dysphagia and postprandial regurgitation. The chest radiographs showed a huge mass in the posterior mediastinum. Barium esophagograms showed narrowing of the middle third esophagus with proximal dilatation. The fibroesophagoscopy demonstrated multiple submucosal nodules below a level 22 cm from the incisor and covered with intact mucosa. CT scans of the chest showed a long segment of circumferential soft tissue in the posterior mediastinum which encircled and involved the upper two thirds of the esophagus. An intrathoracic esophagectomy with cervical esophagogastrostomy via the substernal route was performed. Grossly, multiple confluent myomatous nodules circumferentially involved the upper and middle third of the esophagus. Histologic findings showed diffuse leiomyomatosis of the esophagus. CONCLUSION Esophageal leiomyomatosis should be considered in a young patient with long-standing dysphagia in whom smooth, tapered esophageal narrowing on barium study and circumferential esophageal wall thickening on CT scan are seen. An esophagectomy combined with a reconstruction procedure is indicated.
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Affiliation(s)
- Y L Cheng
- Division of Thoracic Surgery, Department of Surgery, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan
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24
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Guillem P, Delcambre F, Cohen-Solal L, Triboulet JP, Antignac C, Heidet L, Quandalle P. Diffuse esophageal leiomyomatosis with perirectal involvement mimicking Hirschsprung disease. Gastroenterology 2001; 120:216-20. [PMID: 11208731 DOI: 10.1053/gast.2001.20883] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/02/2022]
Abstract
We describe a 25-year-old woman with diffuse esophageal leiomyomatosis. During childhood, achalasia was mistakenly diagnosed in this patient. Subsequently, she underwent cardiomyotomy and developed symptoms of Hirschsprung disease. These symptoms were caused by infiltration of the esophageal and rectal walls by benign muscular hypertrophy. The pseudo-Hirschsprung disorder was manifested by chronic severe constipation, with consistent manometric findings. Clitoral hypertrophy and vulvar and periurethral leiomyoma were also present. Genetic analysis demonstrating deletion of the COL4A5/COL4A6 locus and the discovery of microscopic hematuria implied that the patient could transmit both diffuse leiomyomatosis and the Alport syndrome.
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Affiliation(s)
- P Guillem
- Department of Digestive and General Surgery, France.
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25
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Otto E, Betz R, Rensing C, Schätzle S, Kuntzen T, Vetsi T, Imm A, Hildebrandt F. A deletion distinct from the classical homologous recombination of juvenile nephronophthisis type 1 (NPH1) allows exact molecular definition of deletion breakpoints. Hum Mutat 2000; 16:211-23. [PMID: 10980528 DOI: 10.1002/1098-1004(200009)16:3<211::aid-humu4>3.0.co;2-y] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Juvenile nephronophthisis, an autosomal recessive cystic kidney disease, is the most common genetic cause of end-stage renal disease in children and young adults. We recently identified by positional cloning the causative gene, NPHP1. Its gene product nephrocystin may play a role in focal adhesion and adherens junction signaling. Approximately 80% of all patients with NPH1 carry large homozygous deletions, which contain the NPHP1 gene. These common deletions are positioned within a complex arrangement of large inverted and direct repeats, suggesting unequal recombination as a potential cause for their origin. In this study we have characterized the deletion breakpoints in a family with juvenile nephronophthisis that bears a unique maternal deletion of the NPHP1 gene, which is not the result of an event of homologous recombination. We molecularly characterized the centromeric and telomeric deletion breakpoints by extensive genomic sequencing, Southern blot analysis, and cloning and sequencing of the junction fragment. We were able to exactly localize the breakpoints at the position of two guanines. The centromeric breakpoint was positioned within intron 2 of the NPHP1 gene 360 bp downstream of the 5' end of a complete LINE-1 element. Multiple topoisomerase I and II consensus sequences were found at the breakpoint sites, suggesting the involvement of topoisomerase II in the deletion mechanism. These findings provide the first data on a potential mechanism for a deletion of the NPHP1 gene, that most likely is not the result of an event of homologous recombination and thereby distinct from the known common deletions.
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Affiliation(s)
- E Otto
- University Children's Hospital, D-79106 Freiburg University, Freiburg, Germany
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26
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Abstract
The patient was a 22-year-old woman who had presented in early childhood with gastroesophageal reflux and who subsequently underwent surgery. It was commented upon by the surgeons at that time that the esophagus was abnormally thickened. The patient subsequently presented during her first pregnancy with a vulval tumor, which proved histologically to be a leiomyoma. She was also found to have a grossly dilated esophagus and was thought to have achalasia. However, endoscopic ultrasound imaging showed gross hypertrophy of the mid- and distal esophageal wall, with only mild symptoms of dysphagia, which had been long-standing. The appearance of the esophagus was consistent with diffuse esophageal leiomyomatosis. In view of the associated vulval leiomyoma, the patient demonstrated esophagovulvar syndrome.
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Affiliation(s)
- L A Thomas
- Department of Gastroenterology, Morriston Hospital, Swansea, UK
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27
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Abstract
Alport syndrome (AS) is a genetically heterogeneous disease arising from mutations in genes coding for basement membrane type IV collagen. About 80% of AS is X-linked, due to mutations in COL4A5, the gene encoding the alpha 5 chain of type IV collagen (alpha 5[IV]). A subtype of X-linked Alport syndrome (XLAS) in which diffuse leiomyomatosis is an associated feature reflects deletion mutations involving the adjacent COL4A5 and COL4A6 genes. Most other patients have autosomal recessive Alport syndrome (ARAS) due to mutations in COL4A3 or COL4A4, which encode the alpha 3(IV) and alpha 4(IV) chains, respectively. Autosomal dominant AS has been mapped to chromosome 2 in the region of COL4A3 and COL4A4. The features of AS reflect derangements of basement membrane structure and function resulting from changes in type IV collagen expression. The primary pathologic event appears to be the loss from basement membranes of a type IV collagen network composed of alpha 3, alpha 4, and alpha 5(IV) chains. While this network is not critical for normal glomerulogenesis, its absence appears to provoke the overexpression of other extracellular matrix proteins, such as the alpha 1 and alpha 2(IV) chains, in glomerular basement membranes, leading to glomerulosclerosis. The diagnosis of AS still relies heavily on histologic studies, although routine application of molecular genetic diagnosis will probably be available in the future. Absence of epidermal basement membrane expression of alpha 5(IV) is diagnostic of XLAS, so in some cases kidney biopsy may not be necessary for diagnosis. Analysis of renal expression of alpha 3(IV)-alpha 5(IV) chains may be a useful adjunct to routine renal biopsy studies, especially when ultrastructural changes in the GBM are ambiguous. There are no specific therapies for AS. Spontaneous and engineered animal models are being used to study genetic and pharmacologic therapies. Renal transplantation for AS is usually very successful. Occasional patients develop anti-GBM nephritis of the allograft, almost always resulting in graft loss.
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Affiliation(s)
- C E Kashtan
- Department of Pediatrics, University of Minnesota Medical School, Minneapolis 55455, USA.
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28
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Zheng K, Harvey S, Sado Y, Naito I, Ninomiya Y, Jacobs R, Thorner PS. Absence of the alpha6(IV) chain of collagen type IV in Alport syndrome is related to a failure at the protein assembly level and does not result in diffuse leiomyomatosis. THE AMERICAN JOURNAL OF PATHOLOGY 1999; 154:1883-91. [PMID: 10362815 PMCID: PMC1866637 DOI: 10.1016/s0002-9440(10)65446-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
X-linked Alport syndrome is a progressive nephropathy associated with mutations in the COL4A5 gene. The kidney usually lacks the alpha3-alpha6 chains of collagen type IV, although each is coded by a separate gene. The molecular basis for this loss remains unclear. In canine X-linked hereditary nephritis, a model for X-linked Alport syndrome, a COL4A5 mutation results in reduced mRNA levels for the alpha3, alpha4, and alpha5 chains in the kidney, implying a mechanism coordinating the production of these 3 chains. To examine whether production of alpha6 chain is under the same control, we studied smooth muscle cells from this animal model. We determined the canine COL4A5 and COL4A6 genes are separated by 435 bp, with two first exons for COL4A6 separated by 978 bp. These two regions are >/= 78% identical to the human sequences that have promoter activity. Despite this potential basis for coordinated transcription of the COL4A5 and COL4A6 genes, the alpha6 mRNA level remained normal in affected male dog smooth muscle while the alpha5 mRNA level was markedly reduced. However, both alpha5 and alpha6 chains were absent at the protein level. Our results suggest that production of the alpha6 chain is under a control mechanism separate from that coordinating the alpha3-alpha5 chains and that the lack of the alpha6 chain in Alport syndrome is related to a failure at the protein assembly level, raising the possibility that the alpha5 and alpha6 chains are present in the same network. The lack of the alpha6 chain does not obviously result in disease, in particular leiomyomatosis, as is seen in Alport patients with deletions involving the COL4A5 and COL4A6 genes.
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Affiliation(s)
- Keqin Zheng
- Hospital for Sick Children and University of Toronto, Toronto, Canada; the Divisions of Immunology†
| | - Scott Harvey
- Hospital for Sick Children and University of Toronto, Toronto, Canada; the Divisions of Immunology†
| | | | - Ichiro Naito
- Shigei Medical Research Institute, Okayama, Japan; the Department of Molecular Biology and Biochemistry,§
| | - Yoshifumi Ninomiya
- Okayama University Medical School, Okayama, Japan; and the Department of Pathobiology,¶
| | - Robert Jacobs
- Ontario Veterinary College and University of Guelph, Guelph, Canada
| | - Paul S. Thorner
- Hospital for Sick Children and University of Toronto, Toronto, Canada; the Divisions of Immunology†
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29
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Segal Y, Peissel B, Renieri A, de Marchi M, Ballabio A, Pei Y, Zhou J. LINE-1 elements at the sites of molecular rearrangements in Alport syndrome-diffuse leiomyomatosis. Am J Hum Genet 1999; 64:62-9. [PMID: 9915944 PMCID: PMC1377703 DOI: 10.1086/302213] [Citation(s) in RCA: 82] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
Deletions encompassing the 5' termini of the paired type IV collagen genes COL4A5 and COL4A6 on chromosome Xq22 give rise to Alport syndrome (AS) and associated diffuse leiomyomatosis (DL), a syndrome of disseminated smooth-muscle tumors involving the esophagus, large airways, and female reproductive tract. In this study, we report isolation and characterization of two deletion junctions. The first, in a patient described elsewhere, arose by a nonhomologous recombination event fusing a LINE-1 (L1) repetitive element in intron 1 of COL4A5 to intron 2 of COL4A6, resulting in a 13.4-kb deletion. The second, in a previously undescribed family, arose by unequal homologous recombination between the same L1 and a colinear L1 element in intron 2 of COL4A6, resulting in a>40-kb deletion. L1 elements have contributed to the emergence of this locus as a site of frequent recombinations by diverse mechanisms. These give rise to AS-DL by disruption of type IV collagen and perhaps other as yet unidentified genes, evidenced by deletions as small as 13.4 kb.
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Affiliation(s)
- Y Segal
- Renal Division, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA 02115, USA
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