Project description:Gr-1+ myeloid cells are recruited in prostate conditioanal Pten null tumours (Ptenpc-/-). To identify the secreted factors that may be released by Gr-1+ cells and epithelial cells in the tumour microenvironment, we compared, by gene expression analysis, the cytokine profile of Gr-1+ myeloid cells sorted from Ptenpc-/- tumours with the profile of immune cell-depleted Ptenpc-/- epithelial cells. qRT-PCR validation for IL-10, IL1rn, IL-1α, IL-6, VEGF, TNFα, CXCL1, CCL2 and CXCL12 was also performed. Pten pc-/- 8 weeks old mice were sacrificed and whole prostates were isolated and processed to single cell suspension. mRNA from sorted Gr-1+ myeloid cells and epithelial cells was used for gene expression analysis. Cells sorted from 3 mice/each experiment were pulled together. 2 independent experiments were performed.
Project description:Gr-1+ myeloid cells are recruited in prostate conditioanal Pten null tumours (Ptenpc-/-). To identify the secreted factors that may be released by Gr-1+ cells and epithelial cells in the tumour microenvironment, we compared, by gene expression analysis, the cytokine profile of Gr-1+ myeloid cells sorted from Ptenpc-/- tumours with the profile of immune cell-depleted Ptenpc-/- epithelial cells. qRT-PCR validation for IL-10, IL1rn, IL-1α, IL-6, VEGF, TNFα, CXCL1, CCL2 and CXCL12 was also performed.
Project description:Chronic inflammation is known to associate with prostate cancer development, but how epithelium-associated cancer initiating events cross-talk to inflammatory cells during prostate cancer initiation and progression is largely unknown. Using the Pten null murine prostate cancer model, we show an expansion of Gr-1+CD11b+ myeloid-derived suppressor cells (MDSCs) occurring intra-prostatically immediately following epithelium-specific Pten deletion without expansion in hematopoietic tissues. This MDSC expansion is accompanied by sustained immune suppression. Prostatic Gr-1+CD11b+ cells, but not those isolated from the spleen of the same tumor bearing mice, suppress T cell proliferation and express high levels of Arginase 1 and iNOS. Mechanistically, loss of PTEN in the epithelium leads to a significant upregulation of genes within the inflammatory response and cytokine-cytokine receptor interaction pathways, including Csf-1 and IL-1β, two genes known to induce MDSC expansion and immunosuppressive activities. Treating Pten null mice with the selective CSF-1 receptor inhibitor GW2580 decreases MDSC infiltration and relieves the associated immunosuppressive phenotype. Our study indicates that epithelium-associated tumor initiating events trigger the secretion of inflammatory cytokines and promote localized MDSC expansion and immune suppression, thereby promoting tumor progression. Laser-capture microdissection was used to extract epithelial cells from murine benign and Pten null prostate tumors. Their transcript levels were measured by the custom Agilent 4x44K whole mouse genome expression oligonucleotide microarrays. Each cohort had three biological replicates.
Project description:Differentially expressed genes of CD11b+Gr-1+ immature myeloid cells (IMCs) in the bone marrow and colonic tumor setting of histidine decarboxylase (HDC)-KO mice were examined by microarray (Affymetrix Mouse 430.2 array). Myeloid differentiation-related candidate genes were sought to be isolated and functionally studied. Total RNA of HDC-expressing CD11b+Gr-1+ IMCs of bone marrow were extracted from HDC-EGFP and HDC-EGFP/HDC-KO mice (3 mice in each group). CD11b+Gr-1+ myeloid-derived suppressor cells (MDSCs) of colon tumor were sorted from 10-12 colon tumors of WT and HDC-KO mice (5 mice in each group), and pooled to extract total RNA for microarray studies. Two technical replicates for each of the four groups. Four sets of comparisons were performed to screen for upregulated or downregulated genes in the HDC-KO CD11b+Gr-1+ IMCs or MDSCs (experiment group) compared to the WT group: (1) HDC-expressing CD11b+Gr-1+ IMCs of bone marrow of HDC KO mice compared to bone marrow IMCs of WT mice; (2) CD11b+Gr-1+ MDSCs in tumors of HDC-KO mice compared to WT mice; (3) CD11b+Gr-1+ MDSCs of WT colon tumors compared to IMCs in the WT bone marrow; and (4) CD11b+Gr-1+ MDSCs of colon tumors of HDC-KO mice compared to IMCs in the bone marrow of HDC-KO mice.
Project description:Chronic inflammation is known to associate with prostate cancer development, but how epithelium-associated cancer initiating events cross-talk to inflammatory cells during prostate cancer initiation and progression is largely unknown. Using the Pten null murine prostate cancer model, we show an expansion of Gr-1+CD11b+ myeloid-derived suppressor cells (MDSCs) occurring intra-prostatically immediately following epithelium-specific Pten deletion without expansion in hematopoietic tissues. This MDSC expansion is accompanied by sustained immune suppression. Prostatic Gr-1+CD11b+ cells, but not those isolated from the spleen of the same tumor bearing mice, suppress T cell proliferation and express high levels of Arginase 1 and iNOS. Mechanistically, loss of PTEN in the epithelium leads to a significant upregulation of genes within the inflammatory response and cytokine-cytokine receptor interaction pathways, including Csf-1 and IL-1β, two genes known to induce MDSC expansion and immunosuppressive activities. Treating Pten null mice with the selective CSF-1 receptor inhibitor GW2580 decreases MDSC infiltration and relieves the associated immunosuppressive phenotype. Our study indicates that epithelium-associated tumor initiating events trigger the secretion of inflammatory cytokines and promote localized MDSC expansion and immune suppression, thereby promoting tumor progression Custom Agilent 4x44K whole mouse genome expression oligonucleotide microarrays were used to measure transcript levels in murine Pten null prostate cancer cell lines. Benign mouse prostate epithelia as wild type control against cell lines. Each cohort had three biological replicates.
Project description:Chronic inflammation is known to associate with prostate cancer development, but how epithelium-associated cancer initiating events cross-talk to inflammatory cells during prostate cancer initiation and progression is largely unknown. Using the Pten null murine prostate cancer model, we show an expansion of Gr-1+CD11b+ myeloid-derived suppressor cells (MDSCs) occurring intra-prostatically immediately following epithelium-specific Pten deletion without expansion in hematopoietic tissues. This MDSC expansion is accompanied by sustained immune suppression. Prostatic Gr-1+CD11b+ cells, but not those isolated from the spleen of the same tumor bearing mice, suppress T cell proliferation and express high levels of Arginase 1 and iNOS. Mechanistically, loss of PTEN in the epithelium leads to a significant upregulation of genes within the inflammatory response and cytokine-cytokine receptor interaction pathways, including Csf-1 and IL-1β, two genes known to induce MDSC expansion and immunosuppressive activities. Treating Pten null mice with the selective CSF-1 receptor inhibitor GW2580 decreases MDSC infiltration and relieves the associated immunosuppressive phenotype. Our study indicates that epithelium-associated tumor initiating events trigger the secretion of inflammatory cytokines and promote localized MDSC expansion and immune suppression, thereby promoting tumor progression
Project description:Chronic inflammation is known to associate with prostate cancer development, but how epithelium-associated cancer initiating events cross-talk to inflammatory cells during prostate cancer initiation and progression is largely unknown. Using the Pten null murine prostate cancer model, we show an expansion of Gr-1+CD11b+ myeloid-derived suppressor cells (MDSCs) occurring intra-prostatically immediately following epithelium-specific Pten deletion without expansion in hematopoietic tissues. This MDSC expansion is accompanied by sustained immune suppression. Prostatic Gr-1+CD11b+ cells, but not those isolated from the spleen of the same tumor bearing mice, suppress T cell proliferation and express high levels of Arginase 1 and iNOS. Mechanistically, loss of PTEN in the epithelium leads to a significant upregulation of genes within the inflammatory response and cytokine-cytokine receptor interaction pathways, including Csf-1 and IL-1β, two genes known to induce MDSC expansion and immunosuppressive activities. Treating Pten null mice with the selective CSF-1 receptor inhibitor GW2580 decreases MDSC infiltration and relieves the associated immunosuppressive phenotype. Our study indicates that epithelium-associated tumor initiating events trigger the secretion of inflammatory cytokines and promote localized MDSC expansion and immune suppression, thereby promoting tumor progression.
Project description:Differentially expressed genes of CD11b+Gr-1+ immature myeloid cells (IMCs) in the bone marrow and colonic tumor setting of histidine decarboxylase (HDC)-KO mice were examined by microarray (Affymetrix Mouse 430.2 array). Myeloid differentiation-related candidate genes were sought to be isolated and functionally studied.
Project description:Myeloid derived Suppressor cells (MDSC) are heterogenous popluation of cells consists of two major subsets namely the monocytic Gr-1dull/int. and granulocytic (Gr-1high). These distinct two subsets use different mechanism to inhibit T cell response. In addition, how the function of these subsets is regulated is not known yet. The Gr-1dull/int. MDSC are suppressing T cells through IFNg dependent nitric oxide dependent manner. However, the exact suppressive mechanism of Gr-1high MDSC is not clear. Here we studied the role of a cytokine IFNg on the suppressive function of Gr-1high MDSC by comparing the gene expression of Gr-1high cells cultured alone versus those cultured with T cells which donot produce IFNgamma. CD11b+Gr-1high cells were purified from the splenocyte of CT-26 colon tumor bearing mice. The purified CD11b+Gr-1high MDSCs were cultured with IFNg-/- antigen specific T cells and re- sorted after 48h and RNA was extracted and gene expression was analyzed using topic-defined PIQORTM Immunology Microarrays.