Integrative radiogenomic analysis for genomic signatures in glioblastomas presenting leptomeningeal dissemination
MEDICINE
Authors: You, Hye Jin; Park, Ho-Young; Kim, Jinkuk; Lee, In-Hee; Seol, Ho Jun; Lee, Jung-Il; Kim, Sung Tae; Kong, Doo-Sik; Nam, Do-Hyun
Abstract
Despite therapeutic advances, the prognosis for glioblastoma (GBM) remains poor. In particular, leptomeningeal dissemination (LMD) has a dismal prognosis. The aim of this study was to identify tumor molecular phenotype, which has a great propensity to develop LMD. Between May 2004 and December 2012, a total of 145 GBM tumor samples were obtained from data registry. A total of 20 of the 145 patients with GBM were found to develop LMD. A specialized radiologist confirmed the diagnosis of LMD on magnetic resonance imaging. To clarify the genomic signatures in GBM with LMD, we performed integrative analysis of whole transcriptome sequencing and copy number alteration in the radiological features indicating LMD phenotypes in GBM. Eleven newly diagnosed patients with GBM with LMD had worse prognosis than those without LMD (median 5.55 vs. 12.94 months, P<0.0001). Integrating analysis using gene expression based on the change of copy number revealed that SPOCK1, EHD2, SLC2A3, and ANXA11 were highly expressed with the gain of copy number, compared with the gene expression in the non-LMD group. In addition, it was demonstrated that NME2, TMEM100, and SIVA1 were downregulated with the loss of copy number. We also found that mesenchymal subtype accounted for 50% in LMD group, whereas mesenchymal subtype consisted of 29% in non-LMD group, even though there was no statistical significance (P=0.06). Through this radiogenomic analysis, we suggested the possibility of finding candidate genes associated with LMD and highlighted the significance of integrating approach to clarify the molecular characteristics in LMD.
Copy-Number Variation of the Glucose Transporter Gene SLC2A3 and Congenital Heart Defects in the 22q11.2 Deletion Syndrome
AMERICAN JOURNAL OF HUMAN GENETICS
Authors: Mlynarski, Elisabeth E.; Sheridan, Molly B.; Xie, Michael; Guo, Tingwei; Racedo, Silvia E.; McDonald-McGinn, Donna M.; Gai, Xiaowu; Chow, Eva W. C.; Vorstman, Jacob; Swillen, Ann; Devriendt, Koen; Breckpot, Jeroen; Digilio, Maria Cristina; Marino, Bruno; Dallapiccola, Bruno; Philip, Nicole; Simon, Tony J.; Roberts, Amy E.; Piotrowicz, Malgorzata; Bearden, Carrie E.; Eliez, Stephan; Gothelf, Doron; Coleman, Karlene; Kates, Wendy R.; Devoto, Marcella; Zackai, Elaine; Heine-Suner, Damian; Shaikh, Tamim H.; Bassett, Anne S.; Goldmuntz, Elizabeth; Morrow, Bernice E.; Emanuel, Beverly S.
Abstract
The 22q11.2 deletion syndrome (22q11DS; velocardiofacial/DiGeorge syndrome; VCFS/DGS) is the most common microdeletion syndrome and the phenotypic presentation is highly variable. Approximately 65% of individuals with 22q11DS have a congenital heart defect (CHD), mostly of the conotruncal type, and/or an aortic arch defect. The etiology of this phenotypic variability is not currently known. We hypothesized that copy-number variants (CNVs) outside the 22q11.2 deleted region might increase the risk of being born with a CHD in this sensitized population. Genotyping with Affymetrix SNP Array 6.0 was performed on two groups of subjects with 22q11DS separated by time of ascertainment and processing. CNV analysis was completed on a total of 949 subjects (cohort 1, n = 562; cohort 2, n = 387), 603 with CHDs (cohort 1, n = 363; cohort 2, n = 240) and 346 with normal cardiac anatomy (cohort 1, n = 199; cohort 2, n = 147). Our analysis revealed that a duplication of SLC2A3 was the most frequent CNV identified in the first cohort. It was present in 18 subjects with CHDs and 1 subject without (p = 3.12 x 10(-3), two-tailed Fisher's exact test). In the second cohort, the SLC2A3 duplication was also significantly enriched in subjects with CHDs (p = 3.30 x 10(-2), two-tailed Fisher's exact test). The SLC2A3 duplication was the most frequent CNV detected and the only significant finding in our combined analysis (p = 2.68 x 10(-4), two-tailed Fisher's exact test), indicating that the SLC2A3 duplication might serve as a genetic modifier of CHDs and/or aortic arch anomalies in individuals with 22q11DS.