Calculating the Tumor Nuclei Content for Comprehensive Cancer Panel Testing.

Comprehensive genetic panel testing generally requires that the analyzed tissues have a percent tumor nuclei (%TN) content of 20% or more to achieve assay performance comparable to the validated specifications. Pathologists play a crucial role in ensuring that the optimal results are achieved by accurately assigning %TN content of the available specimens and selecting the best material to submit for sequencing. This study addresses the issues in evaluating %TN, such as intraobserver variability, and examines whether focused training and feedback can improve pathologist performance. Nine referring institution pathologists (all board-certified and working at the core institute and the alignment hospitals under the National Cancer Genome scheme) evaluated 18 tumors that had been subjected to comprehensive genetic panel testing with the FoundationOne CDx assay. The %TN estimates provided by referring institution pathologists were compared with two standards: %TN assigned by the tumor sequencing institution's pathologist (a board-certified pathologist at Foundation Medicine, Inc.) and the computational %TN estimated from the mutant allele frequencies after sequencing was completed. The pathologists generally overestimated %TN in the first pretraining round of the evaluation, and the differences in the averaged %TN from the tumor sequencing institution and computational standards were statistically significant. However, the posttraining second-round results became significantly concordant with the standards. This study suggests that %TN content is empirically overestimated but the evaluation skill can be improved by providing a training and feedback program.

Design, synthesis, and biological evaluation of a novel series of peripheral-selective noradrenaline reuptake inhibitors-Part 2.

Peripherally selective inhibition of noradrenaline reuptake is a novel mechanism for the treatment of stress urinary incontinence to overcome adverse effects associated with central action. Herein, we describe our medicinal chemistry approach to discover peripheral-selective noradrenaline reuptake inhibitors to avert the risk of P-gp-mediated DDI at the blood-brain barrier. We observed that steric shielding of the hydrogen-bond acceptors and donors (HBA and HBD) of compound 1 reduced the multidrug resistance protein 1 (MDR1) efflux ratio; however, the resulting compound 6, a methoxyacetamide derivative, was mainly metabolized by CYP2D6 and CYP2C19 in the in vitro phenotyping study, implying the risk of PK variability based on the genetic polymorphism of the CYPs. Replacement of the hydrogen atom with a deuterium atom in a strategic, metabolically hot spot led to compound 13, which was mainly metabolized by CYP3A4. To our knowledge, this study represents the first report of the effect of deuterium replacement for a major metabolic enzyme. The compound 13, N-{[(6S,7R)-7-(4-chloro-3-fluorophenyl)-1,4-oxazepan-6-yl]methyl}-2-[(2H(3))methyloxy]acetamide hydrochloride, which exhibited peripheral NET selective inhibition at tested doses in rats, increased urethral resistance in a dose-dependent manner.

Design, synthesis, and biological evaluation of a novel series of peripheral-selective noradrenaline reuptake inhibitors - Part 3.

Peripheral-selective inhibition of noradrenaline reuptake is a novel mechanism for the treatment of stress urinary incontinence to overcome adverse effects associated with central action. Here, we describe our medicinal chemistry approach to discover a novel series of highly potent, peripheral-selective, and orally available noradrenaline reuptake inhibitors with a low multidrug resistance protein 1 (MDR1) efflux ratio by cyclization of an amide moiety and introduction of an acidic group. We observed that the MDR1 efflux ratio was correlated with the pKa value of the acidic moiety. The resulting compound 9 exhibited favorable PK profiles, probably because of the effect of intramolecular hydrogen bond, which was supported by a its single-crystal structure. The compound 9, 1-{[(6S,7R)-7-(4-chloro-3-fluorophenyl)-1,4-oxazepan-6-yl]methyl}-2-oxo-1,2-dihydropyridine-3-carboxylic acid hydrochloride, which exhibited peripheral NET-selective inhibition at tested doses in rats by oral administration, increased urethral resistance in a dose-dependent manner.

Prevention of Helicobacter pylori-induced gastric cancers in gerbils by a DNA demethylating agent.

Suppression of aberrant DNA methylation is a novel approach to cancer prevention, but, so far, the efficacy of the strategy has not been evaluated in cancers associated with chronic inflammation. Gastric cancers induced by Helicobacter pylori infection are known to involve aberrant DNA methylation and associated with severe chronic inflammation in their early stages. Here, we aimed to clarify whether suppression of aberrant DNA methylation can prevent H. pylori-induced gastric cancers using a Mongolian gerbil model. Administration of a DNA demethylating agent, 5-aza-2'-deoxycytidine (5-aza-dC), to gerbils (0.125 mg/kg for 50-55 weeks) decreased the incidence of gastric cancers induced by H. pylori infection and N-methyl-N-nitrosourea (MNU) treatment from 55.2% to 23.3% (P < 0.05). In gastric epithelial cells, DNA methylation levels of six CpG islands (HE6, HG2, SB1, SB5, SF12, and SH6) decreased to 46% to 68% (P < 0.05) of gerbils without 5-aza-dC treatment. Also, the global DNA methylation level decreased from 83.0% ± 4.5% to 80.3% ± 4.4% (mean ± SD) by 5-aza-dC treatment (P < 0.05). By 5-aza-dC treatment, Il1b and Nos2 were downregulated (42% and 58% of gerbils without, respectively) but Tnf was upregulated (187%), suggesting that 5-aza-dC treatment induced dysregulation of inflammatory responses. No obvious adverse effect of 5-aza-dC treatment was observed, besides testicular atrophy. These results showed that 5-aza-dC treatment can prevent H. pylori-induced gastric cancers and suggested that removal of induced DNA methylation and/or suppression of DNA methylation induction can become a target for prevention of chronic inflammation-associated cancers.

Suppressive effects of fruit-juice concentrate of Prunus mume Sieb. et Zucc. (Japanese apricot, Ume) on Helicobacter pylori-induced glandular stomach lesions in Mongolian gerbils.

Helicobacter pylori (Hp) infection is an important factor in human gastric disorders, including chronic active gastritis, peptic ulcers, intestinal metaplasia and cancer. Since epidemiologic studies overwhelmingly agree on a protective influence of fruits and vegetables in reducing the risk of gastric neoplasia and processed foods made from Prunus mume Sieb. et Zucc. (Japanese apricot or "Ume" in Japanese) are traditionally known for their miscellaneous medical effects, in the present study we investigated the efficacy of a fruit-juice concentrate of Japanese apricot (CJA) in the glandular stomach of Hp-infected Mongolian gerbils. Hp-inoculated gerbils were given CJA in their drinking water at concentrations of 1 and 3% for 10 weeks. The microscopic scores for gastritis and mucosal hyperplasia in the CJA groups were significantly lower than in the Hp-inoculated control group, with dose-dependence. Real-time PCR was performed to quantitate Hp by demonstrating urease A gene amount using gerbils glyceraldehyde-3-phosphate dehydrogenase (GAPDH) gene as an internal control. Average relative urease A gene dosage in the glandular stomach in the 1 and 3% CJA and Hp-inoculated control groups was 26.6 +/- 11.6% (average +/- SE), 30.3 +/- 10.5%, 100 +/- 40.9%, respectively, the fruit-juice concentrate causing significant lowering (P<0.01 and P<0.05, respectively, with 1 and 3%). These findings suggest that suppressive effects on gastric cancer development might also be expected as a result of decreased numbers of Hp and improvement of Hp-induced chronic active gastritis on administration of CJA.