Search results for "Downregulation"

The soluble form of pan-RTK inhibitor and tumor suppressor LRIG1 mediates downregulation of AXL through direct protein–protein interaction in gliobla…

2019

Abstract Background Targeted approaches for inhibiting epidermal growth factor receptor (EGFR) and other receptor tyrosine kinases (RTKs) in glioblastoma (GBM) have led to therapeutic resistance and little clinical benefit, raising the need for the development of alternative strategies. Endogenous LRIG1 (Leucine-rich Repeats and ImmunoGlobulin-like domains protein 1) is an RTK inhibitory protein required for stem cell maintenance, and we previously demonstrated the soluble ectodomain of LRIG1 (sLRIG1) to potently inhibit GBM growth in vitro and in vivo. Methods Here, we generated a recombinant protein of the ectodomain of LRIG1 (sLRIG1) and determined its activity in various cellular GBM mo…

MiR-24 induces chemotherapy resistance and hypoxic advantage in breast cancer

2017

// Giuseppina Roscigno 1, 2, * , Ilaria Puoti 1, 2, * , Immacolata Giordano 1 , Elvira Donnarumma 3 , Valentina Russo 1 , Alessandra Affinito 1 , Assunta Adamo 1 , Cristina Quintavalle 1, 2 , Matilde Todaro 4 , Maria dM Vivanco 5 , Gerolama Condorelli 1, 2 1 Department of Molecular Medicine and Medical Biotechnology, “Federico II” University of Naples, Naples, Italy 2 IEOS, CNR, Naples, Italy 3 IRCCS-SDN, Naples, Italy 4 Department of Pathobiology and Medical Biotechnology, University of Palermo, Palermo, Italy 5 CIC bioGUNE, Centre for Cooperative Research in Biosciences, Derio, Spain * These authors have contributed equally to the paper as first authors Correspondence to: Gerolama Condore…

Induced arginine transport via cationic amino acid transporter-1 is necessary for human T-cell proliferation

2015

Availability of the semiessential amino acid arginine is fundamental for the efficient function of human T lymphocytes. Tumor-associated arginine deprivation, mainly induced by myeloid-derived suppressor cells, is a central mechanism of tumor immune escape from T-cell-mediated antitumor immune responses. We thus assumed that transmembranous transport of arginine must be crucial for T-cell function and studied which transporters are responsible for arginine influx into primary human T lymphocytes. Here, we show that activation via CD3 and CD28 induces arginine transport into primary human T cells. Both naive and memory CD4(+) T cells as well as CD8(+) T cells specifically upregulated the hum…

Polyphosphate Reverses the Toxicity of the Quasi-Enzyme Bleomycin on Alveolar Endothelial Lung Cells In Vitro

2021

Simple Summary Bleomycin (BLM) is a medication introduced used to treat various types of cancer, including testicular cancer, ovarian cancer, and Hodgkin’s disease. Its most serious side effect is pulmonary fibrosis and impaired lung function. Using A549 human lung cells it is shown that, in parallel to an increased cell toxicity and DNA damage, BLM causes a marked enlargement of the cell nucleus. This effect is abolished by inorganic polyphosphate (polyP), if this physiological polymer is administered together with BLM. The detoxification of BLM is–most likely–caused by the upregulation of the gene encoding the BLM hydrolase which inactivates BLM in vitro and in vivo. This study contribute…

Pterostilbene Decreases the Antioxidant Defenses of Aggressive Cancer Cells In Vivo: A Physiological Glucocorticoids- and Nrf2-Dependent Mechanism

2016

Abstract Aims: Polyphenolic phytochemicals have anticancer properties. However, in mechanistic studies, lack of correlation with the bioavailable concentrations is a critical issue. Some reports had suggested that these molecules downregulate the stress response, which may affect growth and the antioxidant protection of malignant cells. Initially, we studied this potential underlying mechanism using different human melanomas (with genetic backgrounds correlating with most melanomas), growing in nude mice as xenografts, and pterostilbene (Pter, a natural dimethoxylated analog of resveratrol). Results: Intravenous administration of Pter decreased human melanoma growth in vivo. However, Pter, …

Reconstitution of T Cell Proliferation under Arginine Limitation: Activated Human T Cells Take Up Citrulline via L-Type Amino Acid Transporter 1 and …

2017

In the tumor microenvironment, arginine is metabolized by arginase-expressing myeloid cells. This arginine depletion profoundly inhibits T cell functions and is crucially involved in tumor-induced immunosuppression. Reconstitution of adaptive immune functions in the context of arginase-mediated tumor immune escape is a promising therapeutic strategy to boost the immunological anti-tumor response. Arginine can be recycled in certain mammalian tissues from citrulline via argininosuccinate in a two-step enzymatic process involving the enzymes argininosuccinate synthase (ASS) and argininosuccinate lyase (ASL). Here we demonstrate that anti-CD3/anti-CD28-activated human primary CD4+ and CD8+ T c…

Long Non-coding Antisense RNA TNRC6C-AS1 Is Activated in Papillary Thyroid Cancer and Promotes Cancer Progression by Suppressing TNRC6C Expression

2018

Context: Evidences have shown the important role of long non-coding antisense RNAs in regulating its cognate sense gene in cancer biology. Objective: Investigate the regulatory role of a long non-coding antisense RNA TNRC6C-AS1 on its sense partner TNRC6C, and their effects on the aggressiveness and iodine-uptake ability of papillary thyroid cancer (PTC). Design: TNRC6C-AS1 was identified as the target long non-coding RNA in PTC by using microarray analysis and computational analysis. In vitro gain/loss-of-function experiments were performed to investigate the effects of TNRC6C-AS1 and TNRC6C on proliferation, apoptosis, migration, invasion and iodine-uptake ability of TPC1 cells. Expressio…

The Anti-Cancer Effect of Mangifera indica L. Peel Extract is Associated to γH2AX-mediated Apoptosis in Colon Cancer Cells

2019

Ethanolic extracts from Mangifera indica L. have been proved to possess anti-tumor properties in many cancer systems. However, although most effects have been demonstrated with fruit pulp extract, the underlying molecular mechanisms of mango peel are still unclear. This study was designed to explore the effects of mango peel extract (MPE) on colon cancer cell lines. MPE affected cell viability and inhibited the colony formation trend of tumor cells, while no effects were observed in human dermal fibroblasts used as a non-cancerous cell line model. These events were a consequence of the induction of apoptosis associated to reactive oxygen species (ROS) production, activation of players of th…

Methionine transsulfuration pathway is upregulated in long-lived humans.

2020

Available evidences point to methionine metabolism as a key target to study the molecular adaptive mechanisms underlying differences in longevity. The plasma methionine metabolic profile was determined using a LC-MS/MS platform to systematically define specific phenotypic patterns associated with genotypes of human extreme longevity (centenarians). Our findings demonstrate the presence of a specific plasma profile associated with human longevity characterized by an enhanced transsulfuration pathway and tricarboxylic acid (TCA) cycle intermediates, as well as a reduced content of specific amino acids. Furthermore, our work reveals that centenarians maintain a strongly correlated methionine m…

2020

Abstract Objective Cancer cachexia and muscle loss are associated with increased morbidity and mortality. In preclinical animal models, blocking activin receptor (ACVR) ligands has improved survival and prevented muscle wasting in cancer cachexia without an effect on tumour growth. However, the underlying mechanisms are poorly understood. This study aimed to identify cancer cachexia and soluble ACVR (sACVR) administration-evoked changes in muscle proteome. Methods Healthy and C26 tumour-bearing (TB) mice were treated with recombinant sACVR. The sACVR or PBS control were administered either prior to the tumour formation or by continued administration before and after tumour formation. Muscle…