Project description:Interleukin 6 (IL-6) is a pleiotropic cytokine with diverse roles in homeostasis, inflammation, and cancer. In multiple syngeneic mouse tumor models, we found that blockade of IL-6 signaling (using an IL6R-blocking antibody) synergized with anti-PD-L1 therapy to drive potent anti-tumor CD8 T cell responses and tumor rejection. To better characterize the cell-intrinsic effects of IL-6 signaling in tumor-reactive CD8+ T cells during anti-PD-L1 therapy, we generated mice with genetic IL6R deficiency restricted to CD8 T cells by crossing IL6R.loxp and E8i.CD8.Cre mice (CD8ΔIL6R mice). Compared to WT littermate controls, we found that CD8ΔIL6R mice had stronger respones to anti-PD-L1 therapy in terms of improved CD8 T cell function (e.g. increased production of IFNγ and TNF, measured by flow cytometry) and enhanced tumor control, suggesting that direct IL-6 signaling in CD8 T cells is sufficient to impair anti-tumor immunity. In this study we aimed to characterize the phenotype of IL6R-deficient CD8 T cells in more detail via whole-transcriptome profiling. CD8ΔIL6R and WT littermates were implanted with MC38 tumors in the right flank; when tumors reached ~150mm3 in volume, animals were randomized to isotype control or anti-PD-L1 treatment. CD8 T cells were FACS-purified from tumor tissue 7 days later and profiled by bulk RNAseq. Compared to cells from WT mice, CD8 T cells from CD8ΔIL6R mice showed increased expression of interferon-driven gene signatures, increased expression of cell cycle genes, and increased expression of genes critical for oxidative phosphorylation. In contrast, WT cells had higher expression of genes associated with naive and memory precursor cells. Thus, IL-6 signaling in tumor-reactive CD8 T cells limits their capacity to differentiate into potent anti-tumor effectors.
Project description:Pro-growth mutations enable malignancy but for proliferation to proceed, energy and substrates cannot be limiting. However, unrestricted metabolic activation would be self-terminating if it depletes tumor resources. Cancer cells could avoid this by alternating between basal and activated metabolic states, thereby producing dynamic, population-level metabolic heterogeneity that rations resources. Single-cell metabolic phenotyping of pancreatic ductal adenocarcinoma cells identified MIA-PaCa-2 as having broad heterogeneity of fermentative metabolism. Cells sorted by greater lactic acid efflux capacity had higher fermentative rates when subsequently cultured. However, this phenotype was unrelated to cell-cycling or glycolytic and respiratory gene expression, and persisted for less than a week. Transcriptomics linked the higher fermentation with IL6R-STAT3 signaling. Accordingly, IL6R-positive cells were more active metabolically. Episodic activation of metabolism arises from delayed negative feedback via SOCS3 on IL6R-STAT3. We propose that switching between metabolic states allows cell-cohorts to take turns in progressing energy-intense processes without over-burdening shared resources.
Project description:EBNA1 is the EBV-encoded nuclear antigen required for viral episome maintenance during latency. EBNA1 is a sequence specific DNA binding protein with high affinity binding sites for the viral genome, especially OriP. EBNA1 can also bind sequence specifically to a large number of sites in the host cellular genome, but the function of these binding sites has remained elusive. EBNA1 is also known to provide a host cell survival function, but the molecular mechanisms accounting for this function are not completely understood. Here, we show by integrating ChIP-Seq and RNA-Seq with experimental validation that MEF2B, IL6R, and EBF1 are high confidence target genes of EBNA1 that are essential for viability of B-lymphocytes latently infected with EBV. We show that EBNA1 binds to ~1000 sites with many, but not all, universally bound in different cell types, including Burkitt lymphoma (BL) and nasopharyngeal carcinoma (NPC). We find that a large subset of EBNA1 binding sites are located proximal to transcription start sites and correlate genome-wide with transcription activity. EBNA1 bound to genes of high significance for B-cell growth and function, including MEF2B, IL6R, EBF1, RNF145, POU2F1, KDM4C, FGR, EGFR, LAIR, CDC7, CD44, and IL17A. EBNA1 depletion from latently infected LCLs results in the loss of cell proliferation, and the loss of gene expression for some EBNA1-bound genes, including MEF2B, EBF1, and IL6R. Depletion of MEF2B, EBF1, or IL6R partially phenocopies EBNA1-depletion by decreasing EBV-positive cell growth and viability. These findings indicate that EBNA1 binds to a large cohort of cellular genes important for cell viability, and implicates EBNA1 as a master coordinator of host cell gene expression important for enhanced survival of latently infected cells. Examination of EBNA1 binding in Raji, MutuI, LCL and C666-1 cells and EBNA1 knockdown effect on mRNA gene expression in LCL
Project description:Transcriptional profiling of the small colony variant (SCV) S. aureus isolate (JKD6229) compared to the parent isolate with a normal phenotype (JKD6210). Both isolates were from a patient with persistent S. aureus infection, and the SCV strain arose during failed antibiotic therapy.
Project description:Analysis of whole genome gene expression in control and PARKIN patient lines. The hypothesis tested in the present study was that the deficient of PARKIN expression affects multiple pathways. Results provide important information on relationship between PARKIN and mitochondria related gene expression. Total RNA obtained from patient fibroblast and iPSC compare to control fibroblast and iPSC.