Endocan Promotes Pro-Tumorigenic Signaling in Lung Cancer Cells: Modulation of Cell Proliferation, Migration and lncRNAs H19 and HULC Expression.

Endocan is a circulating proteoglycan secreted by several cell lines and identified as a potential biomarker of inflammation and angiogenesis. Endocan-increased expression has been found in a broad spectrum of human tumors, including lung cancer, and is associated with a poor prognosis. To elucidate the possible mechanism, this study aimed to investigate the role of endocan in non-small-cell lung carcinoma (NSCLC) using an in vitro model of cultured cells. Endocan expression was knocked down by using a specific small interfering RNA. The effects of endocan knockdown have been evaluated on VEGF-A, VEGFR-2, HIF-1α, the long non-coding RNAs H19 and HULC expression, and AKT and ERK 1/2 degree of activation. Cell migration and proliferation have been studied as well. VEGF-A, VEGFR-2, HIF-1α, and the long non-coding RNAs H19 and HULC expression were significantly affected by endocan knockdown. These effects correlated with a reduction of cell migration and proliferation and of AKT and ERK 1/2 activation. Our findings suggest that endocan promotes a more aggressive cancer cell phenotype in NSCLC.

Endocan Knockdown Down-Regulates the Expression of Angiogenesis-Associated Genes in Il-1ß Activated Chondrocytes.

Endocan is a small soluble proteoglycan (PG) known to be involved in inflammation and angiogenesis. Increased endocan expression was found in the synovia of arthritic patients and chondrocytes stimulated with IL-1ß. Considering these findings, we aimed to investigate the effects of endocan knockdown on the modulation of pro-angiogenic molecules expression in a model of IL-1ß-induced inflammation in human articular chondrocytes. Endocan, VEGF-A, MMP-9, MMP-13, and VEGFR-2 expression was measured in both normal and endocan knockdown chondrocytes stimulated with IL-1ß. VEGFR-2 and NF-kB activation were also measured. Results have shown that endocan, VEGF-A, VEGFR-2, MMP-9, and MMP-13 were significantly up-regulated during IL-1ß-induced inflammation; interestingly, the expression of such pro-angiogenic molecules and NF-kB activation were significantly reduced by endocan knockdown. These data support the hypothesis that endocan released by activated chondrocytes may be involved in the mechanisms that stimulate cell migration and invasion, as well as angiogenesis, in the pannus of arthritic joints.

Corrigendum: Adenosine receptor stimulation improves glucocorticoid-induced osteoporosis in a rat model.

[This corrects the article DOI: 10.3389/fphar.2017.00558.].

Methylome Analysis in Nonfunctioning and GH-Secreting Pituitary Adenomas.

Pituitary adenomas (PAs), usually benign lesions, can sometimes present with "aggressive" features (rapid growth, local invasiveness, scarce response to conventional treatments). Despite the fact that a few genetic alterations have been associated to this clinical behavior, the role of epigenetic modifications, mainly methylation and miRNAs activity, is now opening new frontiers in this field. We evaluated the methylation profile of 21 PA (11 GH-omas, 10 nonfunctioning tumors-NFPAs) samples from TNS surgery and 5 normal pituitaries, collected at our neurosurgery between 2015 and 2017. DNA was extracted and sequenced, selecting 184,841 target regions. Moreover, methylation profiles were correlated with demographic, radiological, and clinicopathological features. NFPAs showed higher methylation levels vs. GH-omas, with 178 differentially methylated regions (DMRs) mainly consisting of noncoding and intronic sequences, and mostly localized in the open sea regions. We also found three hypermethylated genes (C7orf50, GNG7, and BAHCC1) involved in tumorigenesis processes and potentially influencing pituitary tumor pathophysiology. Among the clinicopathological features, only the maximum diameter resulted significantly higher in NFPAs. Our data provide further evidence of the complex epigenetic background of pituitary tumors. In line with the current literature, we confirmed a significant prevalence of hypermethylation in NFPAs vs. GH-omas, whose pathophysiological consequence is yet to be defined.

Identification of 2-thioxoimidazolidin-4-one derivatives as novel noncovalent proteasome and immunoproteasome inhibitors.

This paper describes the design, synthesis, and biological evaluation of 2-thioxoimidazolidin-4-one derivatives as inhibitors of proteasome and immunoproteasome, potential targets for the treatment of hematological malignancies. In particular, we focused our efforts on the design of noncovalent inhibitors, which might be a promising therapeutic option potentially devoid of drawbacks and side-effects related to irreversible inhibition. Among all the synthesized compounds, we identified a panel of active inhibitors with Ki values towards one or two chymotrypsin-like activities of proteasome (ß5c) and immunoproteasome (ß5i and ß1i subunits) in the low micromolar range. Docking studies suggested a unique binding mode of the molecules in the catalytic site of immunoproteasome proteolytic subunits.

Activation of the EPOR-ß common receptor complex by cibinetide ameliorates impaired wound healing in mice with genetic diabetes.

Diabetes is characterized by poor wound healing which currently lacks an efficacious treatment. The innate repair receptor (IRR) is a master regulator of tissue protection and repair which is expressed as a response injury or metabolic stress, including in diabetes. Activation of the IRR might provide benefit for diabetic wound healing. A specific IRR agonist cibinetide was administered in an incisional wound healing model performed mice with genetic diabetes (db+/db+) and compared to the normal wild-type. Animals were treated daily with cibinetide (30µg/kg/s.c.) or vehicle and euthanized 3, 7, and 14days after the injury to quantitate vascular endothelial growth factor (VEGF), malondialdehyde (MAL), phospho-Akt (pAkt), phospho e-NOS (p-eNOS), and nitrite/nitrate content within the wound. Additional evaluations included quantification of skin histological change, angiogenesis, scar strength, and time to complete wound closure. Throughout the wound healing process diabetic animals treated with vehicle exhibited increased wound MAL with reduced VEGF, pAkt, peNOS and nitrite/nitrate, all associated with poor re-epitheliziation, angiogenesis, and wound breaking strength. Cibenitide administration significantly improved these abnormalities. The results suggest that cibinetide-mediated IRR activation may represent an interesting strategy to treat diabetes-associated wound healing.

Adenosine Receptor Stimulation Improves Glucocorticoid-Induced Osteoporosis in a Rat Model.

Glucocorticoid-induced osteoporosis (GIO) is a secondary cause of bone loss. Bisphosphonates approved for GIO, might induce jaw osteonecrosis; thus additional therapeutics are required. Adenosine receptor agonists are positive regulators of bone remodeling, thus the efficacy of adenosine receptor stimulation for treating GIO was tested. In a preventive study GIO was induced in Sprague-Dawley rats by methylprednisolone (MP) for 60 days. Animals were randomly assigned to receive polydeoxyribonucleotide (PDRN), an adenosine A2 receptor agonist, or PDRN and DMPX (3,7-dimethyl-1-propargylxanthine, an A2 antagonist), or vehicle (0.9% NaCl). Another set of animals was used for a treatment study, following the 60 days of MP-induction rats were randomized to receive (for additional 60 days) PDRN, or PDRN and DMPX (an adenosine A2 receptor antagonist), or zoledronate (as control for gold standard treatment), or vehicle. Control animals were administered with vehicle for either 60 or 120 days. Femurs were analyzed after treatments for histology, imaging, and breaking strength analysis. MP treatment induced severe bone loss, the concomitant use of PDRN prevented the developing of osteoporosis. In rats treated for 120 days, PDRN restored bone architecture and bone strength; increased b-ALP, osteocalcin, osteoprotegerin and stimulated the Wnt canonical and non-canonical pathway. Zoledronate reduced bone resorption and ameliorated the histological features, without significant effects on bone formation. Our results suggest that adenosine receptor stimulation might be useful for preventing and treating GIO.

Cadmium-Induced Oxidative Stress Impairs Glycemic Control in Adolescents.

Experimental evidence suggests that cadmium (Cd) boosts oxidative stress that may result in toxicity on the endocrine system also in humans. The aim of this study was to investigate the glycemic control and oxidative stress markers in male adolescents with increased urinary levels of cadmium. We investigated 111 males, aged 12-14 years, living in a polluted area of Sicily and a control age-matched population (n = 60) living 28-45 km far from the polluted site. Malondialdehyde (MDA), total antioxidant activity (TAC), metallothionein-1A (MT-1A) gene expression, insulin resistance by the homeostatic model assessment (HOMA-IR), and urinary cadmium were investigated. Cd levels were significantly higher in adolescents living in the polluted area than in control age-matched subjects. Adolescents with elevated Cd levels had a significant increase in MDA, MT-1A, and HOMA-IR and reduced TAC compared to the control group. A robust correlation was found between urinary cadmium and MT-1A, HOMA-IR, and MDA whereas an inverse correlation was identified between urinary cadmium and TAC. This study indicates that cadmium burden alters glycemic control in adolescents and suggests that oxidative stress plays a key role in cadmium-induced insulin resistance, increasing the risk of developing metabolic disorders.