Search results for "Immune system"
showing 10 items of 2885 documents
Circulating mir-320a promotes immunosuppressive macrophages M2 phenotype associated with lung cancer risk
2019
miRNAs play a central role in the complex signaling network of cancer cells with the tumor microenvironment. Little is known on the origin of circulating miRNAs and their relationship with the tumor microenvironment in lung cancer. Here, we focused on the cellular source and relative contribution of different cell types to circulating miRNAs composing our risk classifier of lung cancer using in vitro/in vivo models and clinical samples. A cell‐type specific expression pattern and topography of several miRNAs such as mir‐145 in fibroblasts, mir‐126 in endothelial cells, mir‐133a in skeletal muscle cells was observed in normal and lung cancer tissues. Granulocytes and platelets are the major …
Granulocyte-macrophage-colony-stimulating factor enhances immune responses to melanoma-associated peptides in vivo.
1996
Peptide epitopes derived from differentiation antigens of the melanocyte lineage were recently identified in human melanomas as targets for MHC-restricted cytotoxic T lymphocytes (CTL). The characterization of multiple CTL-defined antigenic determinants has opened possibilities of development of antigen-targeted vaccines. In the present study, we determined CTL reactivity against melanoma-associated peptides derived from Melan A/MART-1, tyrosinase, and gp100/Pmel17 in 3 HLA-A2+ melanoma patients. Then, we assessed the immune responses to synthetic melanoma-associated peptides injected intradermally. After 3 cycles of immunization with peptide alone, we used systemic GM-CSF as an adjuvant du…
RORC1 Regulates Tumor-Promoting "Emergency" Granulo-Monocytopoiesis
2015
Cancer-driven granulo-monocytopoiesis stimulates expansion of tumor promoting myeloid populations, mostly myeloid-derived suppressor cells (MDSCs) and tumor-associated macrophages (TAMs). We identified subsets of MDSCs and TAMs based on the expression of retinoic-acid-related orphan receptor (RORC1/RORγ) in human and mouse tumor bearers. RORC1 orchestrates myelopoiesis by suppressing negative (Socs3 and Bcl3) and promoting positive (C/EBPβ) regulators of granulopoiesis, as well as the key transcriptional mediators of myeloid progenitor commitment and differentiation to the monocytic/macrophage lineage (IRF8 and PU.1). RORC1 supported tumor-promoting innate immunity by protecting MDSCs from …
Chemokine receptor CCR7 enhances intrahepatic and lymphatic dissemination of human hepatocellular cancer.
2006
Despite many pathophysiological analyses, the process of tumor dissemination of hepatocellular carcinoma (HCC) remains vague. In diverse tumor entities, expression of the chemokine receptor, CCR7, has been linked to tumor dissemination and poor prognosis. Therefore, we evaluated, whether CCR7 exerts similar effects in human HCC. CCR7 expression analysis was performed in vitro on human hepatoma cell lines (Huh7, Hep3B, wt HepG2, p53 dominant negative transfected HepG2). In addition, CCR7 expression was evaluated in 39 patients with hepatocellular cancer and correlated with both, tumor and patients characteristics. Human hepatocellular carcinoma samples and hepatoma cell lines displayed varia…
Association of childhood leukaemia with factors related to the immune system
1999
The childhood peak of common acute lymphoblastic leukaemia has been proposed as being a rare response to delayed exposure to a common infection. In this context, factors related to the child’s immune system are of special interest. Information on such factors was obtained in a recent German case-control study comprising more than 1000 children with acute leukaemia. Neither being the first-born child, nor a short duration of breastfeeding, indicators of a deficit in viral contacts during infancy or the number of infectious diseases, were significant risk factors. We observed a strong association with fewer routine immunizations with a 3.2-fold increase for those children getting less than fo…
High frequency of functionally active Melan-a-specific T cells in a patient with progressive immunoproteasome-deficient melanoma.
2004
AbstractTumor-reactive T cells play an important role in cancer immunosurveillance. Applying the multimer technology, we report here an unexpected high frequency of Melan-A–specific CTLs in a melanoma patient with progressive lymph node metastases, consisting of 18 and 12.8% of total peripheral blood and tumor-infiltrating CD8+ T cells, respectively. Melan-A–specific CTLs revealed a high cytolytic activity against allogeneic Melan-A–expressing target cells but failed to kill the autologous tumor cells. Loading of the tumor cells with Melan-A peptide reversed the resistance to killing, suggesting impaired function of the MHC class I antigen processing and presentation pathway. Mutations of t…
Analysis of t(15;17) chromosomal breakpoint sequences in therapy-related versus de novo acute promyelocytic leukemia: Association of DNA breaks with …
2010
We compared genomic breakpoints at the PML and RARA loci in 23 patients with therapy-related acute promyelocytic leukemia (t-APL) and 25 de novo APL cases.Eighteen of 23 t-APL cases received the topoisomerase II poison mitoxantrone for their primary disorder. DNA breaks were clustered in a previously reported 8 bp "hot spot" region of PML corresponding to a preferred site of mitoxantrone-induced DNA topoisomerase II-mediated cleavage in 39% of t-APL occurring in patients exposed to this agent and in none of the cases arising de novo (P = 0.007). As to RARA breakpoints, clustering in a 3' region of intron 2 (region B) was found in 65% of t-APL and 28% of de novo APL patients, respectively. S…
Detection of translocations affecting the BCL6 locus in B cell non-Hodgkin's lymphoma by interphase fluorescence in situ hybridization
2001
Structural alterations in 3q27 affecting the BCL6 locus are among the most frequent changes in B-NHL. The aim of the present study was to establish an interphase-FISH assay for the detection of all diverse BCL6 translocations in B-NHL. Two different approaches were tested, one using a PAC-clone spanning the major breakpoint region (MBR) of BCL6 (span-assay), and another using two BAC clones flanking the MBR (flank-assay). Interphase FISH with the span-assay detected the various BCL6 translocations in seven B-NHL cell lines. The dual-color flank-assay was evaluated in two laboratories independently: in normal controls, the cutoff level for false-positive signals was 2.6%, whereas the cutoff …
Tumor infiltration by T lymphocytes expressing chemokine receptor 7 (CCR7) is predictive of favorable outcome in patients with advanced colorectal ca…
2011
Abstract Purpose: An efficient adaptive immunity is critical for a longer survival in cancer. We investigated the prognostic value of tumor infiltration by CD8+ T cells expressing the chemokine-receptor-7 (Tccr7) and the correlation between tumor infiltration by Tccr7 and regulatory CD4+FoxP3+ T cells (Treg) in 76 metastatic colorectal cancer (mCRC) patients enrolled in a phase III trial. Experimental Design: Tccr7 and Treg cell infiltration in tumor samples was quantified by immunohistochemistry. The correlation among Tccr7, Treg tumor infiltration, and patients' outcome was evaluated. Results: High Tccr7 tumor infiltration was predictive of prolonged OS [high vs. low Tccr7 score: median 3…
Immune-modulating effects of the newest cetuximab-based chemoimmunotherapy regimen in advanced colorectal cancer patients.
2012
Cetuximab is a human-murine chimeric monoclonal antibody to the epidermal growth factor receptor, active for advanced colorectal cancer treatment in combination with chemotherapy. Cetuximab mainly acts by inhibiting epidermal growth factor receptor-mediated pathways in cancer cells; however, in the human host, its IgG1 backbone may offer additional antitumor activity that includes FcγRs-mediated antibody-dependent cell cytotoxicity, phagocytosis, cross priming, and tumor-specific T-cell-mediated immune response. These mechanisms are still under active investigation. At this purpose, we have performed an immunologic investigation in advanced colon cancer patients enrolled in an ongoing phase…