Search results for "Oncology"

The embryo-placental CD15-positive "vasculogenic zones" as a source of propranolol-sensitive pediatric vascular tumors.

2015

Abstract Objective Propranolol-induced involution is a unique biological feature of some pediatric vascular tumors, for instance infantile hemangioma (IH), cerebral cavernoma or chorioangioma. Currently, the cellular origin of these distinct tumors is unclear. In this study, we tested the hypothesis that propranolol-responsive vascular tumors are derived from common vessel-forming CD15 + progenitor cells which occur in early gestation. The aim of this study was to identify the tumor-relevant CD15 + progenitors at the early stages of embryo-placental development. Materials and methods Human embryo-placental units of 4–8 weeks gestation and pediatric vascular tumors were tested for expression…

Pathogenetic Mechanisms of Intratumoral Hemorrhage in Meningioma: The Role of Microvascular Differentiation

2016

The transformation of normal cells into neoplastic cells is based on a series of gradual and progressive processes . One of the most important aspects underlying the tumorigenesis ist hat neoplastic proliferation needs mechanisms to ensure cancer development, bypass the body's protective strategies, and survive the apoptotic mechanisms. Subsequently, measures to promote replicative immortality and vascular support will be required. If cancer develops in an area offering excellent vascularization, pre-existing vascular circuits can supporti ts growth .Otherwise,tumor angiogenetic mechanisms will trigger new vascular networks, which will be necessary for tumor survival and expansion. The latt…

Gut Microbiota Condition the Therapeutic Efficacy of Trastuzumab in HER2-Positive Breast Cancer.

2021

Abstract Emerging evidence indicates that gut microbiota affect the response to anticancer therapies by modulating the host immune system. In this study, we investigated the impact of gut microbiota on immune-mediated trastuzumab antitumor efficacy in preclinical models of HER2-positive breast cancer and in 24 patients with primary HER2-positive breast cancer undergoing trastuzumab-containing neoadjuvant treatment. In mice, the antitumor activity of trastuzumab was impaired by antibiotic administration or fecal microbiota transplantation from antibiotic-treated donors. Modulation of the intestinal microbiota was reflected in tumors by impaired recruitment of CD4+ T cells and granzyme B–posi…

HLA-DPB1 mismatch alleles represent powerful leukemia rejection antigens in CD4 T-cell immunotherapy after allogeneic stem-cell transplantation.

2016

Refractory or relapsed acute myeloid leukemia (AML) represents a frequent complication after allogeneic hematopoietic stem-cell transplantation (HSCT). We show herein that primary in vitro stimulation of CD45RA-selected CD4 T cells of stem-cell donors with 10/10 HLA-matched AML blasts results in expansion of cytolytic T-lymphocytes (CTL) that almost all recognize HLA-DPB1 mismatch alleles, which clinically occur in up to 80% of donor-patient pairs. Primary AML blasts were found to strongly express HLA-DPB1, whereas fibroblasts and keratinocytes used as surrogate target cells for graft-versus-host disease did express HLA-DPB1 only upon IFN-γ pre-treatment. Since patients' AML blasts are rare…

Immunological features of coronavirus disease 2019 in patients with cancer.

2020

Background Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2, has caused a major pandemic. Patients with cancer are at higher risk of severe COVID-19. We aimed to describe and compare the immunological features of cancer patients hospitalised for COVID-19 or other concomitant, cancer-related illness. Methods In this prospective study, the clinical and immunological characteristics of 11 cancer patients with COVID-19 and 11 non–COVID-19 cancer patients hospitalised in the same unit at the same period for other medical issues were analysed. We also used 10 healthy volunteers as controls. Peripheral immune parameters were analysed using multiparamet…

Activation of silent mating type information regulation 2 homolog 1 by human chorionic gonadotropin exerts a therapeutic effect on hepatic injury and…

2017

Incidence and prevalence of inflammatory liver diseases has increased over the last years, but therapeutic options are limited. Pregnancy induces a state of immune tolerance, which can result in spontaneous improvement of clinical symptoms of certain autoimmune diseases including autoimmune hepatitis (AIH). We investigated the immune-suppressive mechanisms of the human pregnancy hormone, chorionic gonadotropin (hCG), in the liver. hCG signaling activates silent mating type information regulation 2 homolog 1 (SIRT1), which deacetylates forkhead box o3 (FOXO3a), leading to repression of proapoptotic gene expression, because the immunosuppressive consequence attributed to the absence of caspas…

2021

Although it is widely accepted that cancer-derived extracellular vesicles (EVs) carry DNA cargo, the association of cell-free circulating DNA (cfDNA) and EVs in plasma of healthy humans remains elusive. Using a physiological exercise model, where EVs and cfDNA are synchronously released, we aimed to characterize the kinetics and localization of DNA associated with EVs. EVs were separated from human plasma using size exclusion chromatography or immuno-affinity capture for CD9+, CD63+, and CD81+ EVs. DNA was quantified with an ultra-sensitive qPCR assay targeting repetitive LINE elements, with or without DNase digestion. This model shows that a minute part of circulating cell-free DNA is asso…

CD63 and Dna Mismatch Repair Protein Expression in Prostate Cancer

2021

Abstract Protein expression levels in immunohistochemistry and molecular biomarkers have been reported for their ability to predict recurrence, progression, development of metastases, and patient survival. The molecular features in low- and high-grade prostate cancer can differ and influence treatment decision and prognosis. The objective of the current study was to compare the expression of exosomal biomarkers CD63 and mismatch repair proteins (MSH2, MSH6, MLH1, and PMS2) by immunohistochemistry (IHC) in tissue of patients with prostate cancer and benign hyperplasia. Altogether, 62 patients with prostate acinar adenocarcinoma and 20 patients with prostate benign hyperplasia were enrolled i…

Toll like receptor mediated immune stimulation can be visualized in vivo by [ 18 F]FDG-PET

2016

Abstract Introduction High uptake of [ 18 F]-2-fluorodeoxyglucose ([ 18 F]FDG) by inflammatory cells is a frequent cause of false positive results in [ 18 F]FDG-positron-emission tomography (PET) for cancer diagnostics. Similar to cancer cells, immune cells undergo significant increases in glucose utilization following activation, e.g., in infectious diseases or after vaccination during cancer therapy. The aim of this study was to quantify certain immune effects in vitro and in vivo by [ 18 F]FDG-PET after stimulation with TLR ligands and specific antibodies. Methods In vivo [ 18 F]FDG-PET/magnetic resonance imaging (MRI) and biodistribution was performed with C57BL/6 mice immunized with Cp…

The receptor protein tyrosine phosphatase PTPRJ negatively modulates the CD98hc oncoprotein in lung cancer cells.

2018

PTPRJ, a receptor protein tyrosine phosphatase strongly downregulated in human cancer, displays tumor suppressor activity by negatively modulating several proteins involved in proliferating signals. Here, through a proteomic-based approach, we identified a list of potential PTPRJ-interacting proteins and among them we focused on CD98hc, a type II glycosylated integral membrane protein encoded by SLC3A2, corresponding to the heavy chain of a heterodimeric transmembrane amino-acid transporter, including LAT1. CD98hc is widely overexpressed in several types of cancers and contributes to the process of tumorigenesis by interfering with cell proliferation, adhesion, and migration. We first valid…