Array-Based Comparative Genomic Hybridization Identifies CDK4 and FOXM1 Alterations as Independent Predictors of Survival in Malignant Peripheral Nerve Sheath Tumor
CLINICAL CANCER RESEARCH
Authors: Yu, Jinsheng; Deshmukh, Hrishikesh; Payton, Jacqueline E.; Dunham, Christopher; Scheithauer, Bernd W.; Tihan, Tarik; Prayson, Richard A.; Guha, Abhijit; Bridge, Julia A.; Ferner, Rosalie E.; Lindberg, Guy M.; Gutmann, Rebecca J.; Emnett, Ryan J.; Salavaggione, Lorena; Gutmann, David H.; Nagarajan, Rakesh; Watson, Mark A.; Perry, Arie
Abstract
Purpose: Malignant peripheral nerve sheath tumors (MPNST) are highly aggressive sarcomas with variable patient survival and few known prognostically relevant genomic biomarkers. To identify survival-associated genomic biomarkers, we performed high-resolution array-based comparative genomic hybridization (aCGH) on a large set of MPNSTs. Experimental Design: Candidate gene alterations identified by aCGH in 38 MPNSTs were validated at the DNA, RNA, and protein levels on these same tumors and an independent set of 87 MPNST specimens. Results: aCGH revealed highly complex copy number alterations, including both previously reported and completely novel loci. Four regions of copy number gain were associated with poor patient survival. Candidate genes in these regions include SOX5 (12p12.1), NOL1 and MLF2 (12p13.31), FOXM1 and FKBP1 (12p13.33), and CDK4 and TSPAN31 (12q14.1). Alterations of these candidate genes and several others of interest (ERBB2, MYC and TP53) were confirmed by at least 1 complementary methodology, including DNA and mRNA quantitative real-time PCR, mRNA expression profiling, and tissue microarray-based fluorescence in situ hybridization and immunohistochemistry. Multivariate analysis showed that CDK4 gain/amplification and increased FOXM1 protein expression were the most significant independent predictors for poor survival in MPNST patients (P < 0.05). Conclusions: Our study provides new and independently confirmed candidate genes that could serve as genomic biomarkers for overall survival in MPNST patients. Clin Cancer Res; 17(7); 1924-34. (C)2011 AACR.
A newly characterized human well-differentiated liposarcoma cell line contains amplifications of the 12q12-21 and 10p11-14 regions
VIRCHOWS ARCHIV
Authors: Pedeutour, Florence; Maire, Georges; Pierron, Anne; Thomas, David M.; Garsed, Dale W.; Bianchini, Laurence; Duranton-Tanneur, Valerie; Cortes-Maurel, Annabelle; Italiano, Antoine; Squire, Jeremy A.; Coindre, Jean-Michel
Abstract
While surgery is the usual treatment for localized well-differentiated and dedifferentiated liposarcomas (WDLPS/DDLPS), the therapeutic options for patients with advanced disease are limited. The classical antimitotic treatments are most often inefficient. The establishment of genetically characterized cell lines is therefore crucial for providing in vitro models for novel targeted therapies. We have used spectral karyotyping, fluorescence in situ hybridization with whole chromosome painting and locus-specific probes, and array-comparative genomic hybridization to identify the chromosomal and molecular alterations of a novel cell line established from a recurring sclerosing WDLPS. The karyotype was hypertriploid and showed multiple structural anomalies. All cells retained the presence of a giant marker chromosome that had been previously identified in the primary cell cultures. This giant chromosome contained high-level amplification of chromosomal regions 12q13-21 and lacked the alpha-satellite centromeric sequences associated with WDLPS/DDLPS. The 12q amplicon was large, containing 370 amplified genes. The DNA copy number ranged from 3 to 57. The highest levels of amplification were observed at 12q14.3 for GNS, WIF1, and HMGA2. We analyzed the mRNA expression status by real-time reverse transcription polymerase chain reaction for six genes from this amplicon: MDM2, HMGA2, CDK4, TSPAN31, WIF1, and YEATS4. mRNA overexpression was correlated with genomic amplification. A second amplicon originating from 10p11-14 was also present in the giant marker chromosome. The 10p amplicon contained 62 genes, including oncogenes such as MLLT10, previously described in chimeric fusion with MLL in leukemias, NEBL, and BMI1.