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Article The tumor suppressor gene TRC8/RNF139 is disrupted by a constitutional balanced translocation t(8;22)(q24.13;q11.21) in a young girl with dysgerminoma GIMELLI, Stefania, et al. Abstract BACKGROUND: RNF139/TRC8 is a potential tumor suppressor gene with similarity to PTCH, a tumor suppressor implicated in basal cell carcinomas and glioblastomas. TRC8 has the potential to act in a novel regulatory relationship linking the cholesterol/lipid biosynthetic pathway with cellular growth control and has been identified in families with hereditary renal (RCC) and thyroid cancers. Haploinsufficiency of TRC8 may facilitate development of clear cell-RCC in association with VHL mutations, and may increase risk for other tumor types. We report a paternally inherited balanced translocation t(8;22) in a proposita with dysgerminoma. METHODS: The translocation was characterized by FISH and the breakpoints cloned, sequenced, and compared. DNA isolated from normal and tumor cells was checked for abnormalities by array-CGH. Expression of genes TRC8 and TSN was tested both on dysgerminoma and in the proposita and her father. RESULTS: The breakpoints of the translocation are located within the LCR-B low copy repeat on chromosome 22q11.21, containing the palindromic AT-rich repeat (PATRR) involved in recurrent and non-recurrent [...] Reference GIMELLI, Stefania, et al. The tumor suppressor gene TRC8/RNF139 is disrupted by a constitutional balanced translocation t(8;22)(q24.13;q11.21) in a young girl with dysgerminoma. Molecular Cancer, 2009, vol. 8, p. 52 DOI : 10.1186/1476-4598-8-52 PMID : 19642973 Available at: http://archive-ouverte.unige.ch/unige:5661 Disclaimer: layout of this document may differ from the published version. 1 / 1 Molecular Cancer BioMed Central Research Open Access The tumor suppressor gene TRC8/RNF139 is disrupted by a constitutional balanced translocation t(8;22)(q24.13;q11.21) in a young girl with dysgerminoma Stefania Gimelli1,2, Silvana Beri3, Harry A Drabkin4, Claudio Gambini5, Andrea Gregorio5, Patrizia Fiorio6, Orsetta Zuffardi1,7, Robert M Gemmill4, Roberto Giorda3 and Giorgio Gimelli*6 Address: 1Biologia Generale e Genetica Medica, Università di Pavia, 27100 Pavia, Italy, 2Department of Genetic Medicine and Development, University of Geneva Medical School, and University Hospitals, 1211 Geneva, Switzerland, 3IRCCS E. Medea, 23842 Bosisio Parini (LC), Italy, 4Division of Hematology/Oncology, Dept of Medicine and Hollings Cancer Center, 96 Jonathan Lucas St., Medical University of S. Carolina, Charleston, SC 29425, USA, 5U.O di Istologia ed Anatomia Patologica, Istituto G. Gaslini, 16147 Genova, Italy, 6Laboratorio di Citogenetica, Istituto G. Gaslini, 16147 Genova, Italy and 7Fondazione IRCCS Policlinico San Matteo, Pavia 27100, Italy Email: Stefania Gimelli - [email protected]; Silvana Beri - [email protected]; Harry A Drabkin - [email protected]; Claudio Gambini - [email protected]; Andrea Gregorio - [email protected]; Patrizia Fiorio - [email protected]; Orsetta Zuffardi - [email protected]; Robert M Gemmill - [email protected]; Roberto Giorda - [email protected]; Giorgio Gimelli* - [email protected] * Corresponding author Published: 30 July 2009 Received: 8 June 2009 Accepted: 30 July 2009 Molecular Cancer 2009, 8:52 doi:10.1186/1476-4598-8-52 This article is available from: http://www.molecular-cancer.com/content/8/1/52 © 2009 Gimelli et al; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Abstract Background: RNF139/TRC8 is a potential tumor suppressor gene with similarity to PTCH, a tumor suppressor implicated in basal cell carcinomas and glioblastomas. TRC8 has the potential to act in a novel regulatory relationship linking the cholesterol/lipid biosynthetic pathway with cellular growth control and has been identified in families with hereditary renal (RCC) and thyroid cancers. Haploinsufficiency of TRC8 may facilitate development of clear cell-RCC in association with VHL mutations, and may increase risk for other tumor types. We report a paternally inherited balanced translocation t(8;22) in a proposita with dysgerminoma. Methods: The translocation was characterized by FISH and the breakpoints cloned, sequenced, and compared. DNA isolated from normal and tumor cells was checked for abnormalities by array-CGH. Expression of genes TRC8 and TSN was tested both on dysgerminoma and in the proposita and her father. Results: The breakpoints of the translocation are located within the LCR-B low copy repeat on chromosome 22q11.21, containing the palindromic AT-rich repeat (PATRR) involved in recurrent and non-recurrent translocations, and in an AT-rich sequence inside intron 1 of the TRC8 tumor-suppressor gene at 8q24.13. TRC8 was strongly underexpressed in the dysgerminoma. Translin is underexpressed in the dysgerminoma compared to normal ovary. TRC8 is a target of Translin (TSN), a posttranscriptional regulator of genes transcribed by the transcription factor CREM-tau in postmeiotic male germ cells. Conclusion: A role for TRC8 in dysgerminoma may relate to its interaction with Translin. We propose a model in which one copy of TRC8 is disrupted by a palindrome-mediated translocation followed by complete loss of expression through suppression, possibly mediated by miRNA. Page 1 of 13 (page number not for citation purposes) Molecular Cancer 2009, 8:52 http://www.molecular-cancer.com/content/8/1/52 Background binding inhibitor-like 5, arylsulfatase A, a tetratricopep- Dysgerminomas are rare ovarian tumors most common in tide repeat structure-containing protein, and TRC8. These adolescent women, representing 5–10% of all malignant observations suggest an important function for TRC8 in ovarian tumors in the first two decades of life. They arise germ cells. Here, we describe a paternally inherited bal- from germ cells within the gonad and represent the ovar- anced translocation t(8;22) in a proposita with dysgermi- ian counterpart of testicular seminoma[1]. Histologically noma. The breakpoints of the translocation are located and clinically dysgerminomas are classified as type II within the LCR-B low copy repeat on chromosome Germ Cell Tumors (GCT). 22q11.21, containing the palindromic AT-rich repeat (PATRR) involved in recurrent and non-recurrent translo- The female germ cells enter meiosis during intrauterine cations and in an AT-rich sequence inside intron 1 of the development (11–12 weeks of gestation), whereas for the TRC8 tumor-suppressor gene at 8q24.13. This transloca- male germ cells this only happens after the onset of tion raises the possibility that disruption of TRC8 may puberty. This could explain the difference in incidence of contribute to development of the proposita's dysgermi- the type II gonadal GCTs between females and males and noma. the median age of clinical manifestation. In fact, the number of target cells (PGCs/gonocytes) for initiation is Methods significantly lower in females compared with males [2]. Clinical report The proband is the only one child born to healthy non- RNF139/TRC8 (NM_007218; henceforth, TRC8) is a consanguineous parents with an unremarkable family his- potential tumor suppressor gene (TSG) with similarity to tory. Neither cancers nor miscarriages were reported PTCH [3]. Mutations in PTCH result in predisposition to among her relatives. She was born at term after an une- basal cell carcinoma and medulloblastoma, while its inac- ventful pregnancy. At birth, her growth parameters were tivation leads to cell proliferation [4-6]. TRC8 was identi- normal. The neonatal period was normal. She was fied in a family with the constitutional translocation referred to our Institute at the age of 11 years because of t(3;8)(p14.2;q24.1), and hereditary renal cell carcinoma persistent abdominal pain with fever and evidence of a (RCC) and thyroid cancer[3,7,8]. Recently, a second, pelvic solid mass discovered with ultrasonography in independent, family with hereditary kidney cancer was another hospital. discovered that carries a cytogenetically indistinguishable translocation and a VHL mutation. [9]. Secondary loss of A total body CT scan upon admission showed a large (17 the wild type TRC8 allele was observed in a subset of × 12 × 10 cm) inhomogeneous and necrotic mass arising tumor cells, consistent with tumor suppressor function. from the pelvis with important displacement of the uri- TRC8 is a membrane-bound E3 ubiquitin ligase that nary tracts and bilateral hydronephrosis; a concomitant inhibits the growth of cells in a ubiquitylation-dependent peritoneal fluid was also present in the pouch of Douglas. manner [10]. Interestingly, its level and stability are mod- ulated by cholesterol and it interacts with components of No distant lesions were detected in other abdominal the lipid homeostatic machinery, especially INSIG and organs, CNS and lungs. The Tc-99 scintigraphy was nega- the lipid-regulated transcription factors, SREBP1/2 [11]. A tive for bone lesions. Among serum markers, only LDH frequent genetic alteration in both hereditary and spo- (12980 U/L) (N.V. 84–362 U/L) and β-hCG (113 U/L) radic RCC is mutation of VHL, which encodes the target- (N.V. <5 U/L) were abnormal for age, suggesting the ing subunit of another ubiquitin