Project description:Desmoplastic small round cell tumor (DSRCT) is a rare pediatric cancer caused by the EWSR1-WT1 fusion oncogene. Despite initial response to chemotherapy, DSRCT has a recurrence rate of over 80% leading to poor patient prognosis with a 5-year survival rate of only 15-25%. Owing to the rarity of DSRCT, sample scarcity is a barrier to understanding DSRCT biology and developing effective therapies. Here, we performed RNA-sequencing on a novel pair of primary and recurrent DSRCT tumors harvested from the same patient 5-years apart. To gain insights into gene expression alterations associated with recurrence, we performed pathway analysis on Gene Ontology Biological Processes and KEGG pathways. Upregulated pathways in the recurrent tumor included DNA repair and mRNA splicing related pathways, while downregulated pathways included immune system function and focal adhesion. We further examined the expression of previously identified EWSR1-WT1 regulated targets, a large number of which were enriched in the recurrent tumor. Overall, this study provides novel understanding of DSRCT biology and a new RNA-seq data set to advance future studies.
Project description:Despite aggressive multi-modal treatment, advanced head and neck squamous cell carcinoma (HNSCC) patients are at high risk of recurrence. Matched pairs (n=38) of primary/recurrent tumors were subjected to whole exome and RNA sequencing. Mutational landscapes and genomic copy number alterations indicated diverging clonal origins in a subset of cases. Transcriptional subtyping (classical/CL, basal/BA, inflamed-mesenchymal/IMS) in primary and recurrent HNSCC (n=112) revealed more frequent CL and IMS in primary tumors with low recurrence rates and a prevalence of BA in recurrent tumors associated with p-EMT and early recurrence. 44% of matched cases underwent a subtype change from primary to recurrent tumors, preferably from IMS to BA or CL. In recurrences, HYPOXIA, P-EMT and RADIATION RESISTANCE signatures were up- and TUMOR INFLAMMATION down-regulated compared to index tumors. A therapy-induced selection of transcriptional subtypes demonstrates the importance of molecular characterization of recurrences for second-line therapy decisions to enable optimally tailored treatments.
Project description:The tumor heterogeneity between the primary and recurrent hepatocellular carcinoma (HCC) has rarely been explored. The present study aims to illustrate the heterogeneity between the primary and recurrent tumors by integrating multiomic analyses.
Project description:WGBS was generated for a cohort of ovarian cancer patients to identify DNA methylation changes between primary and recurrent ovarian cancer tumors from patients with and without BRCA1/2 mutations
Project description:RNAseq was generated for a cohort of ovarian cancer patients to identify gene expression changes between primary and recurrent ovarian cancer tumors from patients with and without BRCA1/2 mutations
Project description:Tumor recurrence represents a significant clinical challenge in the treatment and management of breast cancer. To investigate whether copy number aberrations (CNAs) facilitate the re-emergence of tumor growth from residual disease we performed array comparative genomic hybridization (aCGH) on primary and recurrent mammary tumors from an inducible mouse model of type-I insulin-like growth factor receptor (IGF-IR) driven breast cancer. This genome-wide analysis revealed primary and recurrent tumors harbored distinct copy number aberrations (CNAs) with relapsed tumors containing an increased number of gene-level gains and losses. Remarkably, CNAs detected in primary tumors were largely devoid of annotated cancer genes while the vast majority of recurrent tumors harbored at least one CNA containing a known oncogene or tumor suppressor. Specifically, a subset of recurrent tumors carried gains at 6qA2 and 9qA2 which encode the Met and Yap1 oncogenes respectively. The most frequent CNA detected was a focal deletion at 4qC5 involving the Cdkn2a and Cdkn2b tumor suppressor genes. Integrative analysis revealed positive correlations between gene copy number and mRNA expression suggesting Met, Yap1 and Cdkn2a/b may serve as potential driver genes that promote tumor recurrence. Together, these findings indicate that tumor recurrence is facilitated by the acquisition of CNAs with oncogenic potential and provide a framework to dissect the molecular mechanisms that mediate tumor escape from dormancy.