These data suggested that establishment of a suitable biomarker panel would facilitate detection of site-specific kidney injury with high sensitivity.

No abstract

Hepatocellular carcinoma which occurred in one male laboratory cynomolgus monkey at 5 years of age was investigated extensively by immunological, histopathological and electron-microscopic examinations. The animal exhibited no abnormalities in clinical laboratory tests including blood-chemistry, except for elevation of protein induced by vitamin K absence or antagonist II (PIVKA-II) in serum, which is one of the hepatic tumor markers. In virus antibody tests, the serum was positive for hepatitis A virus. On necropsy, a mass measuring 60 × 60 × 65 mm was seen in the hepatic left lobe. The tumor mass had a lobulated structure with hemorrhagic and necrotic areas, and was demarcated by thin fibrous capsules. Histopathologically, the tumor was composed of hepatocyte-like cells, having irregular trabecular structure with various thickness, lined by vascular endothelial cells. Cellular atypia such as polynucleated cells, mitotic figures, and invasion into the vascular cavity were also observed. Immunohistochemically, the tumor cells showed positive reaction for anti-PIVKA-II, anti-epithelial membrane antigen (EMA), anti-carcinoembryonic antigen (CEA), and anti-cytokeratin 18, as well as for proliferating cell nuclear antigen (PCNA). On electron-microscopic examination, the tumor cells had a number of tight junctions and formations of bile canaliculi between adjacent cells, basically resembling hepatocytes. This is the first case of hepatocellular carcinoma with PIVKA-II production in monkeys. Serological and immunohistochemical analyses for PIVKA-II are, therefore, practicable for diagnose as hepatocellular carcinoma in nonhuman primates. (J Toxicol Pathol 2002; 15: 61-68)

To facilitate development of the androgen receptor inhibitor, enzalutamide, we developed and validated methods for simultaneous determination of enzalutamide, its carboxylic acid metabolite (M1), and N-desmethyl enzalutamide (M2) in plasma from mice, rats, and dogs, and brain from mice. Following addition of stable isotope-labeled internal standards, plasma and brain samples (0.05 and 0.3 mL, respectively) were mixed with 0.1% formic acid and extracted with tert-butyl methyl ether, and then injected into a liquid chromatography-tandem mass spectrometry system. The eluent was monitored in positive electrospray ionization mode. To bracket the concentrations of the drug and metabolites in study samples, calibration curves were constructed from 20 to 50000 ng/mL for plasma and 10 to 25000 ng/g for brain. Validation data demonstrated that these methods were selective, reproducible, and accurate. Using these methods, brain-to-plasma concentration ratios in mice were determined to be 0.72 for enzalutamide, 0.048 for M1, and 1.4 for M2.

-It is well-known that indomethacin (the cyclooxygenase 1 & 2 inhibitor) and RU486 (or mifepristone, the progesterone receptor antagonist) block follicular rupture in rats. To characterize genetic alterations in unruptured follicles, gene expression profiles in ovarian follicle were analyzed in indomethacin-and RU486-treated female Sprague-Dawley rats. Ovaries are collected at 22:00 on the proestrus day and 10:00 on the following estrus day after a single dose of indomethacin and RU486. Histopathologically, changes depicting responses to LH surge were observed in ovaries, uteri and vagina. Total RNA was extracted from pre-ovulatory follicles or unruptured follicles collected by laser microdissection and analyzed by Genechip ® . Among genes showing statistically significant changes compared to control groups, following changes were considered relevant to induction of unruptured follicles. In indomethacin-treated rats, Wnt4 was down-regulated, suggesting effect on tissue integrity and steroid genesis. In RU486-treated rats, Adamts1, Adamts9, Edn2, Ednra, Lyve1, Plat, and Pparg were down-regulated. These changes suggest effects on proteolysis for extra cellular matrix or surrounding tissue (Adamts1 & 9, and Plat), constriction of smooth muscle surrounding follicles (Edn2, Ednra, and Pparg), follicular fluid (Lyve1), and angiogenesis (Pparg). Down-regulation of angiogenesis related genes (Angpt2, Hmox1, and Vegfa) was observed in both treatment groups. Here, we clarify genetic alterations induced by the inhibition of cyclooxygenase or progesterone receptor.