Project description:Retinoblastoma (RB) is the most prevalent ocular tumor of childhood whose extraocular invasion largely increase metastasis risk. Nevertheless, a single-cell characterization of RB local extension has been lacking. Here, we perform single-cell RNA sequencing (scRNA-seq) 4 RB samples (2 from intraocular and 2 from extraocular RB patients), and integrate public scRNA-seq datasets to characterize the local extension of RB at single-cell level.
Project description:Retinoblastoma (RB) is the most prevalent ocular tumor of childhood, and its extraocular invasion significantly increases the risk of metastasis. Nevertheless, a single-cell characterization of RB local extension has been lacking. Here, we perform single-cell RNA sequencing on four RB samples (two from intraocular and two from extraocular RB patients), and integrate public datasets of five normal retina samples, four intraocular samples, and three extraocular RB samples to characterize RB local extension at the single-cell level. A total of 128,454 qualified cells are obtained in nine major cell types. Copy number variation inference reveals chromosome 6p amplification in cells derived from extraocular RB samples. In cellular heterogeneity analysis, we identified 10, 8, and 7 cell subpopulations in cone precursor like cells, retinoma like cells, and MKI67+ photoreceptorness decreased (MKI67+ PhrD) cells, respectively. A high expression level of SOX4 was detected in cells from extraocular samples, especially in MKI67+ PhrD cells, which was verified in additional clinical RB samples. These results suggest that SOX4 might drive RB local extension. Our study presents a single-cell transcriptomic landscape of intraocular and extraocular RB samples, improving our understanding of RB local extension at the single-cell resolution and providing potential therapeutic targets for RB patients.
Project description:Genomic losses on chromosome 16q are among the most frequent alterations found in retinoblastoma. In this study, Affymetrix GeneChip analyses along with LOH analysis of microsatellie markers was used to identify candidate tumor suppressor loci in a set of retinoblastoma. We used microarrays to identify genes differentially expressed in retinoblastoma with LOH on 16q (M19484, M22590, M22641, M22860) compared to retinoblastoma without alterations in this region (M20517, M22067, M22233, M23209, M23449, M23818, M23896, M23978) Keywords: Disease progression
Project description:Retinoblastoma is a malignant tumor of the retina which most often occurs in children below 5 years of age with an incident rate of about 1 in 15,000 to 18,000 live births. Retinoblastoma is the first ever cancer that was reported to have a genetic basis. It occurs widely due to inactivating mutations in RB1 gene. Gene expression studies, copy number variation analysis, epigenetic profiling including miRNA and methylation of retinoblastoma has been carried to understand the disease mechanism and key players in the disease. Our group has earlier performed differential proteomics of retinoblastoma to identify proteins of therapeutic importance. However, there are no studies to understand the signalling mechanisms associated with retinoblastoma. Hence, global phosphoproteomics of retinoblastoma was carried out to identify signalling events associated with this cancer. Our study identified stress response proteins to be hyper phosphorylated which included H2AFX and sirtuin 1. In particular, Ser140 of H2AFX also known as gamma-H2AX was found to be hyperphosphorylated in retinoblastoma that indicated activation of DNA damage response pathways. We also observed activation of anti-apoptotic proteins in retinoblastoma compared to control. These observations showed activation of survival pathways and signalling networks activated in tumors.
Project description:In order to identify the gene targets of frequently altered chromosomal regions in retinoblastoma, a meta-analysis of genome-wide copy number alterations studies on primary retinoblastoma tissue and retinoblastoma cell lines was performed. Published studies were complemented by copy number and gene expression analysis on primary and cell line samples of retinoblastoma. This dataset includes the gene expression data of the retinoblastoma cell lines
Project description:Gene expression profiles in retinoblastoma by whole Human Genome DNA microarrays in comparison to the normal retina gave an insight into several genes and pathways that were regulated in the tumor. The upregulated and the downregulated genes were further validated by quantitative real time PCR and tissue microarray (TMA) on retinoblastoma tumors. Theoverall goal is to determine the global gene expression profile in retinoblastoma tumors which is first of its kind on a whole genome microarray. Two coloured microarray:retinoblastoma tumor (4 samples) vs. normal retina (4 samples).