title: Gene expression and single nucleotide polymorphism array analyses of spindle cell lipomas and conventional lipomas with 13q14 deletion.
abstract: Spindle cell lipomas (SCL) are circumscribed, usually s.c. tumors that typically occur on the posterior neck, shoulder, and back of middle aged men. Cytogenetically, almost all SCL are characterized by deletions of chromosome arm 13q, often in combination with loss of 16q. Deletions of 13q are seen also in approximately 15% of conventional lipomas. Through single nucleotide polymorphism (SNP) array analyses, we identified two minimal deleted regions (MDR) in 13q14 in SCL. In MDR1, four genes were located, including the tumor suppressor gene RB1. MDR1 in SCL overlapped with the MDR detected in conventional lipomas with 13q14 deletion. In MDR2 in SCL there were 34 genes and the two microRNA (miRNA) genes miR-15a and miR-16-1. Global gene expression analysis was used to study the impact of the deletions on genes mapping to the two SCL-associated MDR. Five genes (C13orf1, DHRS12, ATP7B, ALG11, and VPS36) in SCL and one gene (C13orf1) in conventional lipomas with 13q-deletions were found to be significantly underexpressed compared with control tissues. Quantitative real-time PCR showed that miR-16-1 was expressed at lower levels in SCL than in the control samples. No mutations were found at sequencing of RB1, miR-15a, and miR-16-1. Our findings further delineate the target region for the 13q deletion in SCL and conventional lipomas and show that the deletions are associated with down-regulated expression of several genes, notably C13orf1, which was the only gene to be significantly down-regulated in both tumor types.
authors.affiliation: Department of Clinical Genetics, University and Regional Laboratories, Skåne University Hospital, Lund University, Lund, Sweden. hammurabi.bartuma@med.lu.se
authors.forename: Hammurabi
authors.initials: H
authors.lastname: Bartuma
authors.forename: Karolin H
authors.initials: KH
authors.lastname: Nord
authors.forename: Gemma
authors.initials: G
authors.lastname: Macchia
authors.forename: Margareth
authors.initials: M
authors.lastname: Isaksson
authors.forename: Jenny
authors.initials: J
authors.lastname: Nilsson
authors.forename: Henryk A
authors.initials: HA
authors.lastname: Domanski
authors.forename: Nils
authors.initials: N
authors.lastname: Mandahl
authors.forename: Fredrik
authors.initials: F
authors.lastname: Mertens
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002872:Chromosome Deletion; D025063:Chromosome Disorders / Q000235:genetics*; D002874:Chromosome Mapping / Q000379:methods; D002882:Chromosomes, Human, Pair 13 / Q000235:genetics; D015870:Gene Expression; D016147:Genes, Tumor Suppressor; D006801:Humans; D008067:Lipoma / Q000235:genetics*; D008297:Male; D035683:MicroRNAs / Q000235:genetics; D008875:Middle Aged; D020641:Polymorphism, Single Nucleotide; D016160:Retinoblastoma Protein / Q000235:genetics; D017384:Sequence Deletion / Q000235:genetics
chemical_list: D035683:MicroRNAs; D016160:Retinoblastoma Protein