Project description:Through comprehensive genetic and pharmacological analyses across various models, we have identified glutamine fructose-6-phosphate transaminase 2 (GFPT2) as a key facilitator of immune evasion in EGFR-mutated NSCLC. GFPT2 escalates the expression and glycosylation of PD-L1, PVR and CD276, bolstering their interactions with CD8+T cells, and amplifies CD73 glycosylation, thereby intensifying adenosine-mediated CD8+T cells suppression. These actions collectively reduce tumor cell vulnerability to CD8+T cell-mediated death. Moreover, GFPT2 regulates EGFR glycosylation, which consequentially modulates the EGFR-dependent secretion of CXCL10 and VEGF, thus impeding CD8+T cell infiltration within tumors.
Project description:Pancreatic cancer is a complex disease with a desmoplastic stroma, extreme hypoxia, and inherent resistance to therapy. Understanding the signaling and adaptive response of such an aggressive cancer is key to making advances in therapeutic efficacy and understanding disease progression. Redox factor-1 (Ref-1), a redox signaling protein, regulates the DNA binding activity of several transcription factors, including HIF-1. The conversion of HIF-1 from an oxidized to reduced state leads to enhancement of its DNA binding. In our previously published work, knockdown of Ref-1 under normoxia resulted in altered gene expression patterns on pathways including EIF2, protein kinase A, and mTOR. In this study, single cell RNA sequencing (scRNA-seq) and proteomics were used to explore the effects of Ref-1 on metabolic pathways under hypoxia.Results: We also integrated the scRNA data analysis with the proteomic analysis and found that the differentially expressed genes and pathways identified from the scRNA-seq data are highly consistent to the significant proteins observed in the proteomics data, especially for the upregulated cell cycle and transcription pathways and downregulated metabolic, apoptosis and signaling pathways under hypoxia. Conclusion: The scRNA-seq and proteomics data consistently demonstrated down-regulated central metabolism pathways in APE1/Ref-1 knockdown vs scrambled control under both normoxia and hypoxia conditions. Experimental Methods: scRNA-seq comparing pancreatic cancer cells expressing less than 20% of the Ref-1 protein was analyzed using left truncated mixture Gaussian model. Matched samples were also collected for bulk proteomic analysis of the four conditions. scRNA-seq data was validated using proteomics and qRT-PCR. Ref-1’s role in mitochondrial function was confirmed using mitochondrial function assays and qRT-PCR. Results: We also integrated the scRNA data analysis with the proteomic analysis and found that the differentially expressed genes and pathways identified from the scRNA-seq data are highly consistent to the significant proteins observed in the proteomics data, especially for the upregulated cell cycle and transcription pathways and downregulated metabolic, apoptosis and signaling pathways under hypoxia. Conclusion: The scRNA-seq and proteomics data consistently demonstrated down-regulated central metabolism pathways in APE1/Ref-1 knockdown vs scrambled control under both normoxia and hypoxia conditions.
Project description:SIGLEC15 in tumor microenvironment could dampen cytotoxic functions of T cells, and we blocked SIGLEC15 with mono-antibody to examine functional changes of cell populations in comparison to treatment of IgG.
Project description:To analyze transcriptome changes in the tumor microenvironment caused by loss of macrophage AhR we performed scRNA sequencing analysis.
Project description:We studied the membrane protein compositions of Streptococcus pneumoniae WT and scRNA mutant strains, with or without the CSP1 induction into competence state.
Project description:Macrophages are cells of the innate immune system fundamental to support normal haematopoiesis, fight infection, anti-cancer immunity and tumour progression. However, the function of macrophages in myeloid leukaemias remain largely unknown, due to difficulties in isolating non-transformed cells from the malignant ones. Here we use a state-of-the-art chimeric mouse of chronic myeloid leukaemia (CML) to study in the impact of the dysregulated bone marrow (BM) microenvironment on bystander macrophages. Utilising single cell RNA sequencing (scRNA seq) of Philadelphia chromosome (Ph) negative macrophages and secretome proteomics of murine c-kit+ stem/progenitor cells we have uncovered that macrophages exposed to a CML environment are altered transcriptionally and have reduced phagocytic function