Cancers of unknown primary (CUP) are characterized by chromosomal instability (CIN) compared to metastasis of know origin.
ABSTRACT: Employing genome wide transcriptome analysis,Linear Discriminant Analysis (LDA) and Quadratic Discriminant Analysis (QDA), we created a successful classification model to identify the putative origin of a CUP. Using the classifications of the CUPs enable the comparison of transcriptome profiles from CUPs to the equivalent normal metastasis across the different carcinoma types. Gene Set Enrichment Analysis (GSEA) and Pathway analysis were used to reveal the common biological features characterizing CUPs. The classifier was build using 2208 samples of normal tissue, known primary tumors, metastasis of known origin and tested on 60 CUP samples. 130 of these samples were collected and analyzed as part of the project and submitted to ArrayExpress. The analyses show that CUPs are distinct from metastases of known origin. CUPs exhibit inconsistent expression of conventional cancer biomarkers and QDA derived outlier scores show that CUPs are more distantly related to their primary tumor class than corresponding metastases of known origin. Gene set enrichment analysis showed that CUPs display increased expression of genes involved in DNA damage repair and by employing signatures of chromosome instability (CIN), we found that CUPs are chromosome unstable compared to metastases of known origin.
Project description:Carcinomas of unknown primary (CUP) are characterized by early metastatic dissemination in the absence of a detectable primary tumor. This disease accounts for about 3% of all malignant tumors. Most CUPs are poorly responsive to chemotherapy and have a rapid fatal evolution. The biological mechanisms supporting metastatic growth in various sites combined with regression or absence of growth in the primary site are still poorly understood. The aim of this project was to investigate structural genome alterations specifically detected by CGH-array in CUP but not in classical secondary metastases. The design of the project was as follows : 5 samples representative of CUPs were compared to 3 samples representative of classical secondary metastases. The CUP samples were : a) 3 fresh biopsies containing more than 60 % malignant cells on tissue sections adjacent to the tumor fragment used for DNA extraction (Gal., Pro., Gag.); b) 2 fragment derived from 2 xenografted CUP tumor lines, Capi 1 and Capi 3 respectively. The samples derived from classical secondary metastases were : a) one fresh biopsy fragment derived from the secondary metastasis of a rectal adenocarcinoma (Vuc.); b) fragments of a tumor resulting from a xenograft of Capan 1, an in vitro cell line derived from a pancreatic adenocarcinoma secondary metastasis; 3) fragments of a xenografted tumor derived from a lung adenocarcinoma metastasis called IC14 (NSCLC).
Project description:Carcinomas of unknown primary (CUP) are characterized by early metastatic dissemination in the absence of a detectable primary tumor. This disease accounts for about 3% of all malignant tumors. Most CUPs are poorly responsive to chemotherapy and have a rapid fatal evolution. The biological mechanisms supporting metastatic growth in various sites combined with regression or absence of growth in the primary site are still poorly understood. The aim of this project was to investigate characteristics of gene expression profile specific of CUPs with special attention to genes overexpressed or silenced in CUPs but not in classical secondary metastases. Three series of experiments were performed in 2006 and 2007. In all experiments, the mRNA used as a reference was obtained from diploid untransformed human fibroblasts (MRC5). The CUP samples were 2 xenografted CUP tumors (Capi1 and Capi3) and 4 CUP biopsies including a squamous carcinoma (Aud) and 3 adenocarcinomas (Gal, Pro, Gag). Samples representative of secondary metastases were xenografted tumors derived from metastases of nasopharyngeal carcinoma (C17), lung adenocarcinoma (IC14) and pancreatic adenocarcinoma (xenografted Capan 1 cell line) and one biopsy from a breast carcinoma (Vuc).
Project description:Biopsies (lymph nodes, ascites or hydrothorax) from 60 patients with cancer of unknown primary origin were analyzed. Results provide insight into the molecular pathogenesis of CUP. 60 samples; 1 array per sample
Project description:Optic fissue is a transient opening on the ventral side of developing optic cup. Failure in optic fissue closure will cause coloboma formation. The aim of this study was to compare optic fissue transcriptome with center optic cup to find optic fissue specific genes. Overall design: optic fissue, nasal- and temporal regions of the Optic cups of E11.5 mouse embryos was microdissected using laser-assisted microdissection. Total RNAs were extracted and processed to cRNA library and hybridized to Affymetrix mouse genome 4302.0 arrays. Each region has three biological replicates.
Project description:To test the hypothesis that ablation of the SOX2 in the developing optic cup leads to expansion of peripheral optic cup signaling pathways, we screened whole-genome changes in gene expression in Sox2-mutant eyes compared with controls. Results confirm that ciliary epithelial (peripheral) identity is gained at the expense of neural retinal identity in Sox2-ablated optic cups. Total RNA was isolated from whole eyes enucleated from six wild-type controls and six Sox2-mutant embryos for a total of twelve eyes per genotype. Each embryo (pair of eyes) was analyzed as a single sample.
Project description:Wnt signaling in early eye development, specifically the lens placode shows expression of 12 out of 19 Wnt ligands. We these Wnt activities were suppressed using conditional deletion of Wntless, dramatic phenotypic changes in morphogensis occurred. Microarray analysis of the genes that were changed in response to deletion of Wnt ligands in the developing eye region show direct or indirect responses from the surface ectoderm to the developing RPE and optic cup curvature, creating an overal shape change phenotype in the bilayerd epithelium of the optic cup. Mouse embryos at embryonic stage e10.5 were disected into pbs and eye regions were disected and removed for RNA extraction and hybridization to Affymetrix microarrays. We sought to identify the genes that were changed in response to deletion of Wls from the developing surface ectoderm of the eye region. Genes changed could be the direct or indirect result from deleltion of Wls from the surface ectoderm using the LeCre recombinase gene as a tool for analysis.
Project description:Carcinomas of unknown primary origin constitute 3-5% of all newly diagnosed metastatic cancers, of which the primary source is difficult to classify with current histological methods. Effective cancer treatment depends on early and accurate identification of the tumor, which is why patients with metastases of unknown origin have poor prognosis and short survival. Because microRNA expression is highly tissue specific, the microRNA profile of a metastasis may be used to identify its origin. As a first step to realize this goal, we evaluated the potential of microRNA profiling for identification of the primary tumor of known metastases. 208 formalin-fixed paraffin-embedded samples representing 15 different histologies were profiled on an LNA-enhanced microarray platform, which allows for highly sensitive and specific detection of microRNA. Based on these data, we developed and cross-validated a novel classification algorithm, LASSO (Least Absolute Shrinkage and Selection Operator), which had an overall accuracy of 85%. When the classifier was applied on an independent test set of 48 metastases, the primary site was correctly identified in 42 cases (88% accuracy). Our findings suggest that microRNA expression profiling on paraffin tissue can efficiently predict the primary origin of a tumor, and may provide pathologists with a molecular diagnostic tool that can improve their capability to correctly identify the origin of hitherto unidentifiable metastatic tumors, and eventually, enable tailored therapy. 94 samples
Project description:Identification of genes expressed in a preferential manner in the developing ciliary body/iris will provide a starting point for future functional analyses. To identify candidate genes expressed in a variety of ocular tissues during development, we have profiled single cells from the developing eye. Post hoc identification of the origin of these cells showed that they included cells from the periphery of the developing optic cup. By comparing the expression profiles of these cells to many retinal cell types, candidate genes for preferential expression in the periphery were identified. Overall design: Single retinal cells were isolated in tubes containing lysis buffer, their mRNAs were reverse transcribed, and the resulting cDNAs were PCR amplified for 35 cycles. Labeled cDNA samples were hybridized to Affymetrix 430 2.0 microarrays and the data was normalized using MAS5.0 software. Since the retinal cells isolated during these developmental times had not yet adopted their mature morphologies, a post hoc strategy was employed to classify each cell based upon the expression of clusters of genes (Trimarchi et al., 2008). This classification method allowed for the identification of 21 single cells as developing retinal ganglion (RGC), amacrine (AC) or photoreceptor cells (PR) (Trimarchi et al., 2007) and an additional 42 cells as cycling RPCs (Trimarchi et al., 2008). However, a number of the single cells did not score significantly for any of the retinal cell types. Two cells in particular expressed genes that suggested these cells originated from the developing ciliary body/iris region.
Project description:Breast cancer metastases develop in the bone more frequently than any other site, and are a common cause of morbidity in the form of bone pain, pathological fractures, nerve compression, and life-threatening hypercalcemia. Despite ongoing research efforts, the molecular and cellular mechanisms that regulate breast cancer cell homing to and colonization of the bone as well as resultant pathological bone alteration remain poorly understood. To identify key mediators promoting breast cancer metastasis to bone, we utilized an immunocompetent, syngeneic murine model of breast cancer metastasis employing the mammary tumor cell line NT2.5. Following intracardiac injection of NT2.5 cells in neu-N mice, metastases developed in the bone, liver, and lung, closely mimicking the anatomical distribution of metastases in breast cancer patients. Using an in vivo selection process, we established NT2.5 sub-lines demonstrating an enhanced ability to colonize the bone and liver. Genome-wide cDNA microarray analysis comparing gene expression between parental NT2.5 cells and established sub-lines was performed. Individual samples of RNA from parental NT2.5 cells, early passage (BO3 and LI1) sub-lines, and final passage (BO6 and LI3) sub-lines were compared using GeneChip® Mouse Genome 430 2.0 Arrays
Project description:Samples 1 & 2: Comparison of gene expression between wild type (ecotype Ler) and 35S:CUC1, in which CUP-SHAPED COTYLEDON1, a master regulator of the shoot meristem and boundary establishment, is constitutively expressed under the cauliflower mosaic virus 35S promoter. Samples 3 & 4: Comparison of gene expression between stm-1 (ecotype Ler) and stm-1 35S:CUC1 Overall design: RNA was isolated from cotyledons of 5-day-old (for Ler vs 35S:CUC1) or 10-day-old (for stm vs 35S:CUC1stm) seedlings. Two independent biological replicates were analyzed for each comparison.