Project description:Translocations involving FGFR2 gene fusions are common in cholangiocarcinoma and predict response to FGFR kinase inhibitors. However, response rates and durability of are limited due to the emergence of resistance, typically involving FGFR2 kinase domain mutations, and to sub-optimal dosing, relating to drug adverse effects. Here, we develop biparatopic antibodies targeting the FGFR2 extracellular domain (ECD), as candidate therapeutics. Biparatopic antibodies can overcome drawbacks of bivalent monospecific antibodies, which often show poor inhibitory or even agonist activity against oncogenic receptors. We show that oncogenic transformation by FGFR2 fusions requires an intact ECD. Moreover, by systematically generating biparatopic antibodies targeting distinct epitope pairs in FGFR2 ECD, we identified antibodies that effectively block signaling and malignant growth driven by FGFR2-fusions. Importantly, these antibodies demonstrate efficacy in vivo, synergy with FGFR inhibitors, and activity against FGFR2 fusions harboring kinase domain mutations. Thus, biparatopic antibodies may serve as new treatment options for patients with FGFR2-altered cholangiocarcinoma.
Project description:Dysregulated FGF/FGFR signaling leads to a variety of pathologies. These include cancer as well as congenital syndromes that affect skeleton development, impair the response to injury, and/or result in metabolic disorders. In human cancers, the FGFR genes can be affected by hotspot missense mutations or structural alterations, such as amplifications and fusions/rearrangements. Missense mutations affecting the FGFR extracellular domains (e.g., FGFR3S249C) typically facilitate receptor dimerization and ligand-independent activation whereas kinase domain missense mutations frequently facilitate transition to (e.g., FGFR2N549K) or stabilization of (e.g., FGFR3K650E) an active kinase state. FGFR amplifications result in receptor overexpression. Notably, focal FGFR2 amplifications can also produce C-terminally truncated isoforms owing to genomic breakpoints that perturb intron or the FGFR2 C-terminus-encoding exon 18. FGFR2 and FGFR3 fusion/rearrangement breakpoints typically occur in the I17/E18 hotspot, thus also producing C-terminally truncated receptors. E18-truncated FGFR2 variants (FGFR2E18) indeed act as tumor driver genes. Hence, loss of the C-terminus is vital to render FGFR2 and potentially other FGFRs oncogenic.However, it has remained unclear, which motifs or amino acid residues within the C-terminal tail are most critical to suppress oncogenic FGFR2 signaling. Here we made us of a compendium of Fgfr2E18 and Fgfr2 C-terminal variants to functionally dissect FGFR2E18 signaling and the tumor suppressive nature of the FGFR2 C-terminus.
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:Transcriptional profiling of human mesenchymal stem cells comparing normoxic MSCs cells with hypoxic MSCs cells. Hypoxia may inhibit senescence of MSCs during expansion. Goal was to determine the effects of hypoxia on global MSCs gene expression.
