Identification of heparin-binding EGF-like growth factor (HB-EGF) as a biomarker for lysophosphatidic acid receptor type 1 (LPA1) activation in human breast and prostate cancers

Lysophosphatidic acid (LPA) is a natural bioactive lipid with growth factor-like functions due to activation of a series of six G protein-coupled receptors (LPA₁₋₆). LPA receptor type 1 (LPA₁) signaling influences the pathophysiology of many diseases including cancer, obesity, rheumatoid arthritis, as well as lung, liver and kidney fibrosis. Therefore, LPA₁ is an attractive therapeutic target. However, most mammalian cells co-express multiple LPA receptors whose co-activation impairs the validation of target inhibition in patients because of missing LPA receptor-specific biomarkers. LPA₁ is known to induce IL-6 and IL-8 secretion, as also do LPA₂ and LPA₃. In this work, we first determined the LPA induced early-gene expression profile in three unrelated human cancer cell lines expressing different patterns of LPA receptors (PC3: LPA₁,₂,₆; MDA-MB-231: LPA1,2; MCF-7: LPA₂,₆). Among the set of genes upregulated by LPA only in LPA₁-expressing cells, we validated by QPCR and ELISA that upregulation of heparin-binding EGF-like growth factor (HB-EGF) was inhibited by LPA₁-₃ antagonists (Ki16425, Debio0719). Upregulation and downregulation of HB-EGF mRNA was confirmed in vitro in human MDA-B02 breast cancer cells stably overexpressing LPA₁ (MDA-B02/LPA₁) and downregulated for LPA₁ (MDA-B02/shLPA1), respectively. At a clinical level, we quantified the expression of LPA₁ and HB-EGF by QPCR in primary tumors of a cohort of 234 breast cancer patients and found a significantly higher expression of HB-EGF in breast tumors expressing high levels of LPA₁. We also generated human xenograph prostate tumors in mice injected with PC3 cells and found that a five-day treatment with Ki16425 significantly decreased both HB-EGF mRNA expression at the primary tumor site and circulating human HB-EGF concentrations in serum. All together our results demonstrate that HB-EGF is a new and relevant biomarker with potentially high value in quantifying LPA₁ activation state in patients receiving anti-LPA₁ therapies

Hydrogen oxidation reaction: Evidences of different electrocatalytic activity between α and β Pd–H

The hydrogen oxidation reaction (hor) was studied in steady state conditions on a palladium thin film electrode supported on a gold rotating disc. The electrode surface was characterized by cyclic voltammetry and SEM observation. The hydrogen absorption process was analysed by open circuit potential decay in an acid solution saturated with hydrogen and the kinetic measurements were carried out potentiostatically in the same solution. The results obtained show a marked change on the dependence of the current density on overpotential due to the transition between the α and β phases of the Pd–H system. These results were correlated with appropriate kinetic expressions and the corresponding electrocatalytic activity of both phases was estimated. Keywords: Palladium thin film, Hydrogen oxidation reaction, Electrocatalytic activit

A PK/PD STUDY IN RACHEMIS TURTLES AFTER SINGLE INTRACOELOMIC INJECTION OF MARBOFLOXACIN AT DIFFERENT DOSES.

INTRODUCTION/OBJECTIVE Marbofloxacin (M) belongs to the fluoroquinolone class of antibiotics. It is commonly used in a variety of animal species, mostly in pets. M and other fluoroquinolones resistance is an emerging problem [1]. Thus, there is a need to select dosage regimens based on approaches such as PK/PD integration and modeling to minimize the selection of resistant mutants of bacteria and extend the useful life of antimicrobial agents. The aim of this study was to evaluate its pharmacokinetics and in vivo efficacy after a single intracoelomic injection at different dose rates. MATERIALS AND METHODS 3 groups of 6 healthy adult turtles each (Trachemysscripta) were housed in controlled conditions of temperature and humidity. Randomly, M was administered at 0.4, 2 and 10 mg kg 1 respectively with a single intracoelomic injection. Blood samples were collected from sub-carapacial site and rectal swabs were collected at scheduled times. M concentrations in serum were assayed using an HPLC-FL validated method. Bacteria isolation was performed using blood agar and Hektoen Enteric Agar; in vitro antimicrobial susceptibility test of M was developed with disc diffusion test (Kirby-Bauer Method) RESULTS The PK profiles of M, fit by a bi-compartmental model. The PK were dose dependent. The Tmax and half life ranged between 2.82–4.64 and 16.14–30.68 h, respectively. Bacteria isolation showed the presence of both E. coli and Salmonella spp. All E. coli strains isolates were susceptible to M (diffusion > 18 mm) and were all eliminated within 48 h after administration of any dosage. Salmonella spp. have been isolated only after 48 h and all strains were resistant to M (diffusion < 14 mm). Two turtles in the highest dose group died 2 days after the treatment. CONCLUSIONS The Cmax at the clinical dosing (2 mg kg 1) was slightly higher and drastically lower than those reported in mammals [2] and in CarettaCarettaturles [3] after IM administrations. Interestingly, Salmonella spp. was isolated after 48 h from the administration, probably because, E.coli had a such high concentration as to hide his presence. Moreover, Salmonella spp. shown an unequivocal resistance of M that even at the lowest dose was able to select resistant strains. The results of the present study seem to suggest that even if M is able to reach considerable plasma concentrations, it is also useless to a pathogen for humans

Observations of the Hematological, Hematochemical, and Electrophoretic Parameters in Lactating Donkeys (Equus asinus)

A cross-sectional study was conducted on 92 female donkeys. Blood samples were collected, and the following parameters were evaluated: red blood cell (RBC), white blood cell, neutrophil, lymphocyte, monocyte (MON), eosinophil (EOS) and basophil counts, hemoglobin concentration, mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), mean corpuscular hemoglobin concentration (MCHC), and the hematocrit (HCT), alanine aminotransferase (GPT), aspartate aminotransferase, total proteins, γ-glutamyl-transferase, alkaline phosphatase, creatinine, urea, and blood urea nitrogen and electrophoretic profile. Age (≥2 years ≤ 3 [very young], &gt;3 years ≤ 10 [young], and &gt;10 years ≤ 17 [adult]) and lactation (early lactation [≤3 months], middle [&gt;3 months ≤ 6], and late lactation [&gt;6 months]). Groups were independently analyzed using one-way analysis of variance or Kruskal–Wallis (post hoc test: Bonferroni's or Dunn's multiple test) tests; P was set as &lt;.05. Very young animals had lower EOS than young and adult animals; in addition, they showed the highest MON and RBC and the lowest MCV and GPT; MCHC was lower in adult than that in the very young group; MCH was higher in the adult than that in the very young group; Alpha 2-globulin values were greater in young than those in very young animals; MCH was higher in the late lactation group than that in early lactation; alpha 1 and alpha 2-globulins showed a significant increase from the early to the late lactation period. Values reported herein could provide a useful clinical guide and represent a basis for further research into monitoring the health status of lactating donkeys