Novel pegylated interferon-ß as strong suppressor of the malignant ascites in a peritoneal metastasis model of human cancer.

Malignant ascites manifests as an end-stage event during the progression of a number of cancers and lacks a generally accepted standard therapy. Interferon-ß (IFN-ß) has been used to treat several cancer indications; however, little is known about the efficacy of IFN-ß on malignant ascites. In the present study, we report on the development of a novel, engineered form of human and murine IFN-ß, each conjugated with a polyethylene glycol molecule (PEG-hIFN-ß and PEG-mIFN-ß, respectively). We provide evidence that these IFN-ß molecules retain anti-viral potency comparable to unmodified IFN-ß in vitro and manifested improved pharmacokinetics in vivo. Interestingly, PEG-mIFN-ß significantly inhibited the accumulation of ascites fluid and vascular permeability of the peritoneal membrane in models of ovarian cancer and gastric cancer cell xenograft mice. We further show that PEG-hIFN-ß directly suppresses VEGF165 -induced hyperpermeability in a monolayer of human vascular endothelial cells and that PEG-mIFN-ß enhanced gene expression for a number of cell adhesion related molecules in mouse vascular endothelial cells. Taken together, these findings unveil a hitherto unrecognized potential of IFN-ß in maintaining vascular integrity, and provide proof-of-mechanism for a novel and long-acting pegylated hIFN-ß for the therapeutic treatment of malignant ascites.

Discovery of potent transient receptor potential vanilloid 1 antagonists: design and synthesis of phenoxyacetamide derivatives.

We aimed to discover a novel type of transient receptor potential vanilloid 1 (TRPV1) antagonist because such antagonists are possible drug candidates for treating various disorders. We modified the structure of hit compound 7 (human TRPV1 IC50=411 nM) and converted its pyrrolidino group to a (hydroxyethyl)methylamino group, which substantially improved inhibitory activity (15d; human TRPV1 IC50=33 nM). In addition, 15d ameliorated bladder overactivity in rats in vivo.

In vitro and in vivo pharmacological characterization of the main metabolites of nalfurafine hydrochloride.

Pharmacological characterization of the main metabolites of nalfurafine hydrochloride ((E)-N-[17-(cyclopropylmethyl)-4,5α-epoxy-3,14-dihydroxymorphinan-6ß-yl]-3-(furan-3-yl)-N-methylprop-2-enamide monohydrochloride; a selective κ-opioid receptor agonist and an antipruritic for uremic pruritus in hemodialysis patients in Japan) such as 17-decyclopropylmethylated nalfurafine (de-CPM), 3-glucuronide of nalfurafine (NFA-G) and 3-glucuronide of 17-decyclopropylmethylated nalfurafine (de-CPM-G) was performed in vitro (human opioid receptor radioligand binding assay and forskolin-stimulated cyclic adenosine monophosphate (cAMP) assay) and in vivo (substance P-induced scratching behavior in mice). These main metabolites of nalfurafine showed the low affinities for human κ-, µ- and δ-opioid receptors except for the affinity of de-CPM to κ-opioid receptor (inhibition constant (Ki) values: 5.95nmol/l), which was 24 times lower than that of nalfurafine. Moreover, the main metabolites of nalfurafine had much lower agonistic activities than that of nalfurafine for three opioid receptors in forskolin-stimulated cAMP assays. In the substance P-induced mouse scratching behavior, the subcutaneous administration of each metabolite did not statistically significantly reduce the scratching behavior at doses up to 1000µg/kg which was 100 times higher than the effective dose of nalfurafine. These findings suggest that the main metabolites of nalfurafine do not make any contribution to its pharmacological actions including antipruritic effects in vivo.

Promotion of liver and lung tumorigenesis in DEN-treated cytoglobin-deficient mice.

Cytoglobin (Cygb) is a recently discovered vertebrate globin with molecular characteristics that are similar to myoglobin. To study the biological function of Cygb in vivo, we generated Cygb knockout mice and investigated their susceptibility to N,N-diethylnitrosamine (DEN)-induced tumorigenesis. Four-week-old male mice were administered DEN in drinking water at a dose of 25 ppm for 25 weeks or 0.05 ppm for 36 weeks. Cygb deficiency promoted the DEN-induced development of liver and lung tumors. All Cygb(+/-) and Cygb(-/-) mice treated with 25-ppm DEN exhibited liver tumors, compared with 44.4% of their wild-type counterparts. Lung tumors were present only in Cygb-deficient mice. More than 40% of Cygb(-/-) mice developed liver and lung tumors at the nontoxic dose of DEN (0.05 ppm), which did not induce tumors in wild-type mice. Cygb loss was associated with increased cancer cell proliferation, elevated extracellular signal-regulated kinase and Akt activation, overexpression of IL-1ß, IL-6, Tnfα, and Tgfß3 mRNAs, and hepatic collagen accumulation. Cygb-deficient mice also exhibited increased nitrotyrosine formation and dysregulated expression of cancer-related genes (cyclin D2, p53, Pak1, Src, Cdkn2a, and Cebpa). These results suggest that Cygb deficiency induces susceptibility to cancer development in the liver and lungs of mice exposed to DEN. Thus, globins such as Cygb will shed new light on the biological features of organ carcinogenesis.