Fluorescence in situ hybridization analysis of CCND3 gene as marker of progression in bladder carcinoma.

The aim of this study was to assess patterns of CCND3 gene amplification in bladder cancer and correlate gene status with recurrence-free and progression-free survival. A sequential cohort series of 102 primary bladder tumor samples in which there was enough tissue material to assess CCND3 gene status by fluorescent in situ hybridization (FISH) was the study group. CCND3 gene FISH amplification present in 31.4 percent of bladder carcinomas, was related to tumor progression (p=0.021) and lower time to progression (mean+-SD; 25.75+-15.25 months) as compared to 33.29+-11.0 months in the CCND3 not amplified group (p=0.05). By immunohistochemistry, Cyclin D3 labeling index was higher in the CCND3 amplified group (mean+-SD, 76.69+-27.51) than in not amplified (mean+-SD, 21.57+-7.02) (p less than 0.0001). The univariate survival analysis showed CCND3 gene amplification to be associated to a shorter progression-free survival (p=0.020) together with WHO histological grade (p=0.001) and pT stage category (p less than 0.0001). Cox’s regression analysis selected CCND3 amplification as an independent predictor of progression-free survival (p= 0.030, RR3.561, 95 percent CI 1.128-11.236) together with pT category (p less than 0.0001, RR5.834, 95 percent CI 2.364-14.395). Our FISH analysis suggests that CCND3 gene amplification is a marker of aggressiveness and might be a predictor of tumor progression in bladder urothelial carcinoma.

1q gain and CDT2 overexpression underlie an aggressive and highly proliferative form of Ewing sarcoma.

Despite extensive characterization of the role of the EWS-ETS fusions, little is known about secondary genetic alterations and their clinical contribution to Ewing sarcoma (ES). It has been demonstrated that the molecular structure of EWS-ETS lacks prognostic value. Moreover, CDKN2A deletion and TP53 mutation, despite carrying a poor prognosis, are infrequent. In this scenario identifying secondary genetic alterations with a significant prevalence could contribute to understand the molecular mechanisms underlying the most aggressive forms of ES.We screened a 67 ES tumor set for copy number alterations by array comparative genomic hybridization. 1q gain (1qG), detected in 31% of tumor samples, was found markedly associated with relapse and poor overall and disease-free survival and demonstrated a prognostic value independent of classical clinical parameters. Reanalysis of an expression dataset belonging to an independent tumor set (n=37) not only validated this finding but also led us to identify a transcriptomic profile of severe cell cycle deregulation in 1qG ES tumors. Consistently, a higher proliferation rate was detected in this tumor subset by Ki-67 immunohistochemistry. CDT2, a 1q-located candidate gene encoding a protein involved in ubiquitin ligase activity and significantly overexpressed in 1qG ES tumors, was validated in vitro and in vivo proving its major contribution to this molecular and clinical phenotype. This integrative genomic study of 105 ES tumors in overall renders the potential value of 1qG and CDT2 overexpression as prognostic biomarkers and also affords a rationale for the application of already available new therapeutic compounds selectively targeting the protein-ubiquitin machinery.

Stable interference of EWS-FLI1 in an Ewing sarcoma cell line impairs IGF-1/IGF-1R signalling and reveals TOPK as a new target.

BACKGROUND: Ewing sarcoma is a paradigm of solid tumour -bearing chromosomal translocations resulting in fusion proteins that act as deregulated transcription factors. Ewing sarcoma translocations fuse the EWS gene with an ETS transcription factor, mainly FLI1. Most of the EWS-FLI1 target genes still remain unknown and many have been identified in heterologous model systems. METHODS: We have developed a stable RNA interference model knocking down EWS-FLI1 in the Ewing sarcoma cell line TC71. Gene expression analyses were performed to study the effect of RNA interference on the genetic signature of EWS-FLI1 and to identify genes that could contribute to tumourigenesis. RESULTS: EWS-FLI1 inhibition induced apoptosis, reduced cell migratory and tumourigenic capacities, and caused reduction in tumour growth. IGF-1 was downregulated and the IGF-1/IGF-1R signalling pathway was impaired. PBK/TOPK (T-LAK cell-originated protein kinase) expression was decreased because of EWS-FLI1 inhibition. We showed that TOPK is a new target gene of EWS-FLI1. TOPK inhibition prompted a decrease in the proliferation rate and a dramatic change in the cell's ability to grow in coalescence. CONCLUSION: This is the first report of TOPK activity in Ewing sarcoma and suggests a significant role of this MAPKK-like protein kinase in the Ewing sarcoma biology.