Project description:We analyzed over 40,000 cells from nine pediatric MPAL BM samples to generate a single-cell transcriptomic landscape of B/Myeloid (B/My) and T/Myeloid (T/My) MPAL blasts and associated microenvironment cells. Cell clusters were identified using principal component analysis and uniform manifold approximation and projection (UMAP). Supervised differentially expressed gene (DEG) analysis was performed to identify B/My and T/My MPAL blast-specific signatures. MPAL sample transcriptome profiles were compared with normal BM stem and immune cells to identify MPAL-specific dysregulation. We have for the first time described the single-cell transcriptomic landscape of pediatric MPAL and have demonstrated that B/My and T/My MPAL have unique scRNA-seq profiles distinct from each other with expected overlap with AML and their respective ALL subtype.
Project description:Activation of YAP is frequently observed in cancer and is associated with poor outcomes, making it an attractive target for therapeutic intervention. Previous studies have mainly focused on blocking the interaction of YAP with TEAD transcription factors. Here we took a different approach by interfering with the binding of YAP to the transcription factor B-MYB using MY-COMP, a fragment of B-MYB containing the YAP binding domain fused to a nuclear localization signal. We found that expression of MY-COMP inhibited the binding of B-MYB to YAP, resulting in growth defects, nuclear abnormalities and polyploidization in HeLa cells. Additionally, MY-COMP interfered with normal cell cycle progression of YAP-dependent uveal melanoma cells, but its effects were much weaker in YAP-independent cutaneous melanoma cell lines. MY-COMP antagonized the YAP-dependent expression of MMB-regulated cell cycle genes, providing an explanation for the observed phenotypes. We identified NIMA-related kinase (NEK2) as a candidate target downstream of YAP and B-MYB, contributing to the transformation of YAP-dependent uveal tumor cell lines. Overall, our findings suggest that targeting selected YAP-MMB regulated genes such as NEK2 or inhibiting the WW-domains of YAP to suppress YAP-regulated cell cycle genes could provide a novel mechanism to antagonize the pro-tumorigenic functions of YAP.
Project description:We have used an IGR-N-91 parental cell line established from an involved bone marrow harvested from a high-risk NB (stage 4-NB, 8 year-old boy). These IGR-N-91 neuroblasts were injected subcutaneously into nude mice and a Primary Tumor Xenograft (PTX) was isolated whilst metastatic neuroblasts were isolated from Myocardium (MY) and Bone Marrow (BM). These malignant neuroblasts were further cultured in vitro on bovine corneal extra-cellular matrix to establish sublines (IGR/PTX, IGR/BM and IGR/MY). Agilent oligo microarray analysis was performed to compare gene expression profiles in BM and MY metastatic versus PTX neuroblasts. This analysis used eight microarrays (two replicates plus two dye-swap experiments for both MY and BM cell lines).
