Characterization of JNJ-2482272 [4-(4-Methyl-2-(4-(Trifluoromethyl)Phenyl)Thiazole-5-yl) Pyrimidine-2-Amine] As a Strong Aryl Hydrocarbon Receptor Activator in Rat and Human.

[4-(4-Methyl-2-(4-(trifluoromethyl)phenyl)thiazole-5-yl)pyrimidine-2-amine] (JNJ-2482272), under investigation as an anti-inflammatory agent, was orally administered to rats once daily at 60 mg/kg for 6 consecutive days. Despite high plasma exposure after single administration (Cmax of 7.1 µM), JNJ-2482272 had plasma concentrations beneath the lower limit of quantification (3 ng/ml) after 6 consecutive days of dosing. To determine if JNJ-2482272 is an autoinducer in rats, plated rat hepatocytes were treated with JNJ-2482272 for 2 days. The major hydroxylated metabolites of JNJ-2482272 were isolated and characterized by mass spectrometry and NMR analyses. Compared with the vehicle-treated cells, a concentration-dependent increase was observed in the formation of phase I- and II-mediated metabolites coinciding with greater expression of cytochrome P450s (P450s) and UDP-glucuronosyltransferases (UGTs) in rat hepatocytes. CYP1A1, CYP1A2, CYP1B1, and UGT1A6 transcripts were predominantly induced, suggesting that JNJ-2482272 is an activator of the aryl hydrocarbon receptor (AhR). In a human AhR reporter assay, JNJ-2482272 demonstrated potent AhR activation with an EC50 value of 0.768 nM, a potency more comparable to the strong AhR activator and toxin 2,3,7,8-tetrachloro-dibenzodioxin than to weaker AhR activators 3-methylcholanthrene, ß-naphthoflavone, and omeprazole. In plated human hepatocytes, JNJ-2482272 induced CYP1A1 gene expression with an EC50 of 20.4 nM and increased CYP1A activity >50-fold from basal levels. In human recombinant P450s, JNJ-2482272 was exclusively metabolized by the CYP1 family of enzymes and most rapidly by CYP1A1. The summation of these in vitro findings bridges the in vivo conclusion that JNJ-2482272 is a strong autoinducer in rats and potentially in humans through potent AhR activation. SIGNIFICANCE STATEMENT: Drugs that induce their own metabolism (autoinducers) can lack sustained exposures for pharmacology and safety assessment hindering their development. JNJ-2482272 is demonstrated herein as a strong aryl hydrocarbon receptor (AhR) activator and CYP1A autoinducer, explaining its near complete loss of exposure after repeat administration in rat, which is likely translatable to human (if progressed further) considering its nanomolar potency comparable to "classical" AhR ligands like 2,3,7,8-tetrachloro-dibenzo-dioxin despite bearing a "nonclassical" drug structure.

TNER: a novel background error suppression method for mutation detection in circulating tumor DNA.

BACKGROUND: Ultra-deep next-generation sequencing of circulating tumor DNA (ctDNA) holds great promise as a tool for the early detection of cancer and for monitoring disease progression and therapeutic responses. However, the low abundance of ctDNA in the bloodstream coupled with technical errors introduced during library construction and sequencing complicates mutation detection. RESULTS: To achieve high accuracy of variant calling via better distinguishing low-frequency ctDNA mutations from background errors, we introduce TNER (Tri-Nucleotide Error Reducer), a novel background error suppression method that provides a robust estimation of background noise to reduce sequencing errors. The results on both simulated data and real data from healthy subjects demonstrate that the proposed algorithm consistently outperforms a current, state-of-the-art, position-specific error polishing model, particularly when the sample size of healthy subjects is small. CONCLUSIONS: TNER significantly enhances the specificity of downstream ctDNA mutation detection without sacrificing sensitivity. The tool is publicly available at https://github.com/ctDNA/TNER .