Project description:A Cartes d'Identite des Tumeurs (CIT) project from the French National League Against Cancer (http://cit.ligue-cancer.net ) 25 glioblastoma multiforme tumors hybridized on Illumina SNP and Affymetrix gene expression arrays. Project leader : François DUCRAY (francois.ducray@chu-lyon.fr). CIT Analysis : Julien LAFFAIRE (laffairej@ligue-cancer.net). Note: PFS : progression-free survival, OS: Overall Survival,BCNU : Carmustine (chemotherapy agent). RESPONDER: if the patient has shown or not shown a response to the treatment (Bevacizumab (Avastin) plus Irinotecan). Progression during : If the disease has progressed (cancer relapse or patient's death); otherwise (patient is alive without relapse).
Project description:Purpose: Our study aimed to disclose the specific gene expression profile representing peritoneal relapses inherent in primary gastric cancers and to identify patients at high risk of peritoneal relapse in a prospective study on the basis of the molecular prediction. Experimental Design: RNA samples from 141 primary gastric cancer tissues after curative surgery were profiled using oligonucleotide microarrays covering 30,000 human probes. Firstly we constructed molecular prediction system and validated the robustness and prognostic validity of the analysis by 500 times multiple random sampling in 56 retrospective set consisting of 38 relapse free and 18 peritoneal relapse patients. Secondly we applied this prediction to 85 prospective set to assess the predictive accuracy and prognostic validity. Results: In retrospective phase, 500 times multiple random sampling analysis yielded 68% predictive accuracy in average and 22 gene expression profile associated with peritoneal relapse was identified. This prediction could identify significantly poor prognostic patients. In prospective phase, the molecular prediction yielded 76.9% overall accuracy. KaplanâMeier analysis with peritoneal relapse free survival showed a significant difference between âgood signature groupâ and âpoor signature groupâ (Log-rank p=0.0017). Multivariate analysis by Cox regression hazards model revealed that the molecular prediction was the only independent peritoneal relapse prognostic factor. Conclusions: Gene expression profile inherent in primary gastric cancer tissues can be useful to predict peritoneal relapse prospectively after curative surgery and individualize postoperative management to improve the prognosis of advanced gastric cancers. Of 141 samples, 56 represented the retrospective phase and 85 represented the prospective phase.
Project description:Gene expression profiling of immortalized human mesenchymal stem cells with hTERT/E6/E7 transfected MSCs. hTERT may change gene expression in MSCs. Goal was to determine the gene expressions of immortalized MSCs.
Project description:Background: Around 30% of all stage II colon cancer patients will relapse and die of their disease. At present no objective parameters for identification of high-risk stage II colon cancer patients, who will benefit from adjuvant chemotherapy, are established. With traditional histopathological features definition of high-risk stage II colon cancer patients is inaccurate. Therefore more objective and robust markers for prediction of relapse are needed. DNA copy number aberrations have proven to be robust prognostic markers, but have not been investigated for this specific group of patients. The aim of the present study is to identify chromosomal aberrations that can predict relapse of tumor in patients with stage II colon cancer. Materials and Methods: DNA was isolated from 40 formaldehyde fixed paraffin embedded stage II colon cancer samples with extensive clinicopathological data. Samples where hybridized using Comparative Genomic Hybridization (CGH) arrays to determine DNA copy number changes and microsatellite stability was determined by PCR. To analyze differences between stage II colon cancer patients with and without relapse of tumor a Wilcoxon rank-sum test was implemented with multiple testing correction Results: Patients with stage II colon cancer who had relapse of disease showed significant more losses on chromosome 4, 5, 15q, 17q and 18q. When microsatellite stable (MSS) patients were analyzed separately, only losses on chromosome 4q22.1-4q35.2 predicted worse outcome in stage II colon cancer patients. No differences in clinicopathological characteristics between patients with and without relapse were observed. Conclusion: Losses on 4q22.1-4q35.2 predict worse outcome in MSS stage II colon cancer patients and may aid in the selection of patients for adjuvant therapy.
Project description:Background: Around 30% of all stage II colon cancer patients will relapse and die of their disease. At present no objective parameters for identification of high-risk stage II colon cancer patients, who will benefit from adjuvant chemotherapy, are established. With traditional histopathological features definition of high-risk stage II colon cancer patients is inaccurate. Therefore more objective and robust markers for prediction of relapse are needed. DNA copy number aberrations have proven to be robust prognostic markers, but have not been investigated for this specific group of patients. The aim of the present study is to identify chromosomal aberrations that can predict relapse of tumor in patients with stage II colon cancer. Materials and Methods: DNA was isolated from 40 formaldehyde fixed paraffin embedded stage II colon cancer samples with extensive clinicopathological data. Samples where hybridized using Comparative Genomic Hybridization (CGH) arrays to determine DNA copy number changes and microsatellite stability was determined by PCR. To analyze differences between stage II colon cancer patients with and without relapse of tumor a Wilcoxon rank-sum test was implemented with multiple testing correction Results: Patients with stage II colon cancer who had relapse of disease showed significant more losses on chromosome 4, 5, 15q, 17q and 18q. When microsatellite stable (MSS) patients were analyzed separately, only losses on chromosome 4q22.1-4q35.2 predicted worse outcome in stage II colon cancer patients. No differences in clinicopathological characteristics between patients with and without relapse were observed. Conclusion: Losses on 4q22.1-4q35.2 predict worse outcome in MSS stage II colon cancer patients and may aid in the selection of patients for adjuvant therapy. 40 Stage II colorectal cancer (CRC) tissue samples (FFPE), 16 with and 24 without relapse of tumor
Project description:Kynureninase is a member of a large family of catalytically diverse but structurally homologous pyridoxal 5'-phosphate (PLP) dependent enzymes known as the aspartate aminotransferase superfamily or alpha-family. The Homo sapiens and other eukaryotic constitutive kynureninases preferentially catalyze the hydrolytic cleavage of 3-hydroxy-l-kynurenine to produce 3-hydroxyanthranilate and l-alanine, while l-kynurenine is the substrate of many prokaryotic inducible kynureninases. The human enzyme was cloned with an N-terminal hexahistidine tag, expressed, and purified from a bacterial expression system using Ni metal ion affinity chromatography. Kinetic characterization of the recombinant enzyme reveals classic Michaelis-Menten behavior, with a Km of 28.3 +/- 1.9 microM and a specific activity of 1.75 micromol min-1 mg-1 for 3-hydroxy-dl-kynurenine. Crystals of recombinant kynureninase that diffracted to 2.0 A were obtained, and the atomic structure of the PLP-bound holoenzyme was determined by molecular replacement using the Pseudomonas fluorescens kynureninase structure (PDB entry 1qz9) as the phasing model. A structural superposition with the P. fluorescens kynureninase revealed that these two structures resemble the "open" and "closed" conformations of aspartate aminotransferase. The comparison illustrates the dynamic nature of these proteins' small domains and reveals a role for Arg-434 similar to its role in other AAT alpha-family members. Docking of 3-hydroxy-l-kynurenine into the human kynureninase active site suggests that Asn-333 and His-102 are involved in substrate binding and molecular discrimination between inducible and constitutive kynureninase substrates.
Project description:Purpose: Our study aimed to disclose the specific gene expression profile representing peritoneal relapses inherent in primary gastric cancers and to identify patients at high risk of peritoneal relapse in a prospective study on the basis of the molecular prediction. Experimental Design: RNA samples from 141 primary gastric cancer tissues after curative surgery were profiled using oligonucleotide microarrays covering 30,000 human probes. Firstly we constructed molecular prediction system and validated the robustness and prognostic validity of the analysis by 500 times multiple random sampling in 56 retrospective set consisting of 38 relapse free and 18 peritoneal relapse patients. Secondly we applied this prediction to 85 prospective set to assess the predictive accuracy and prognostic validity. Results: In retrospective phase, 500 times multiple random sampling analysis yielded 68% predictive accuracy in average and 22 gene expression profile associated with peritoneal relapse was identified. This prediction could identify significantly poor prognostic patients. In prospective phase, the molecular prediction yielded 76.9% overall accuracy. Kaplan–Meier analysis with peritoneal relapse free survival showed a significant difference between ‘good signature group’ and ‘poor signature group’ (Log-rank p=0.0017). Multivariate analysis by Cox regression hazards model revealed that the molecular prediction was the only independent peritoneal relapse prognostic factor. Conclusions: Gene expression profile inherent in primary gastric cancer tissues can be useful to predict peritoneal relapse prospectively after curative surgery and individualize postoperative management to improve the prognosis of advanced gastric cancers.
Project description:The goal was to identify gene expression signatures predictive of early relapse among stage IIA/MSS colon cancer patients. A secondary question addressed was whether the invasion front profiles could generate a competitive signature. 39 whole tumor and 35 matched invasion front profiles were generated (4 samples failed) and grouped into \\"early relapse\\" (relapse within 5 years) and \\"no relapse\\" (no relapse for at least 6 years) categories.