Finally, the expression of CYP1A1 was not affected by INCB024360 in both cell types; however, MT significantly increased CYP1A1 expression in RT4 and T24 cells (Fig. be a ligand for AHR. We hypothesized that AHR could be associated with BC progression and that MT could activate AHR in BC. Methods BC patients (and expression of the target genes), a cut-off point was determined for each gene based on the median or ROC curve predicting tumor progression. Correlation analysis was performed confronting the relative expression of the target genes with clinicopathological features (gender, age, tumor grade, stage, and MK-8617 progression). Cell culture Human bladder cancer T24 cells and RT4 cells (HTB-4 and HTB-2, respectively; American Type Culture Collection-ATCC, Manassas, VA, USA) were acquired from the Cell Bank of the Federal University of Rio de Janeiro. T24 cells were cultured in RPMI 1640 Medium (Vitrocell, Campinas, Brazil) supplemented with 10% fetal bovine serum (FBS) and penicillin-streptomycin (Sigma-Aldrich, St. Louis, MO) and maintained at 37?C with 5% CO2. To analyze the effect of IDO inhibitors around the expression of AHR and CYP1A1, RT4 and T24 cells were MK-8617 incubated with 1?M INCB024360 (INCB, Tocris Bioscience, Bristol, UK) or 1?mM 1-methyl-D-tryptophan (MT, Sigma-Aldrich, St. Louis, MO) for 48?h. INCB was dissolved in DMSO (Sigma-Aldrich, St. Louis, MO) for a 1?mM stock solution. MT was dissolved in 0.1?N NaOH for a 20?mM stock solution and then neutralized to pH?7.4 with 0.1?N HCl. Cells were incubated into 6-well plates until 80% confluence. At this time, the medium was removed and medium made up of IDO inhibitors was added. After 48?h, the cells were harvested and pelleted, being frozen at nitrogen and kept at ??80?C for storage until RNA extraction. Supernatant DDR1 was collected and maintained at ??80?C for kynurenine measurement. The experiments were carried out in triplicates and repeated three times at different times. Kynurenine measurement HPLC was performed to measure kynurenine in the cell culture supernatants. Deproteinization of the samples was performed by centrifugation at 5000?g (15?min at 4?C) with 10% trichloroacetic acid (1:1, v/v). After MK-8617 centrifugation, the supernatants and the standards were filtered through a 0.22?m syringe-loaded filter and MK-8617 resolved with a mobile phase of acetonitrile plus sodium acetate buffer (4:96, v/v), pH?4.7. A precolumn of 12.5X4.6?mm and a C18 column (695970C902, Poroshell 120, EC-C18, 4.6x100mm, 4um, Agilent Technologies, Santa Clara, CA, USA) were used. The peak representing kynurenine was detected with the 1220 Infinity II LC Gradient System (G4288B, Agilent Technologies, Santa Clara, USA). A standard curve was built to determine the concentration of the samples (0.5?M, 1.0?M, 2.0?M, 4.0?M, 8.0?M, and 16.0?M). Real-time PCRTotal RNA was extracted from cultured cells using the PureLink? RNA mini kit (12183018A, Invitrogen, California, USA) and PureLink? RNA kit (12,183,016, Invitrogen, California, USA). For cDNA synthesis, SuperScript III Platinum SYBR Green One-Step qRT-PCR Kit (Invitrogen, California, USA) was used. SYBR Green kit MK-8617 (Invitrogen, California, USA Biosystems, California USA) was used in combination with specific primers for IDO1 (sense 5GGTCATGGAGATGTCCGTAA3 and antisense 5ACCAATAGAGAGACCAGGAAGAA3; “type”:”entrez-nucleotide”,”attrs”:”text”:”NM_002164.5″,”term_id”:”323668304″,”term_text”:”NM_002164.5″NM_002164.5), AHR (sense 5 ACATCACCTACGCCAGTCGC3 and antisense 5 TCTATGCCGCTTGGAAGGAT 3; “type”:”entrez-nucleotide”,”attrs”:”text”:”NM_001621.4″,”term_id”:”229577137″,”term_text”:”NM_001621.4″NM_001621.4), CYP1A1 (sense 5 CTATCTGGGCTGTGGGCAA 3 antisense 5 CTGGCTCAAGCACAACTTGG 3; “type”:”entrez-nucleotide”,”attrs”:”text”:”NM_000499.4″,”term_id”:”984655754″,”term_text”:”NM_000499.4″NM_000499.4), and Tata box protein (TBP) as housekeeping (sense 5 TTCGGAGAGTTCTGGGATTGTA3 and antisense 5TTCGGAGAGTTCTGGGATTGTA 3; “type”:”entrez-nucleotide”,”attrs”:”text”:”NM_003194.4″,”term_id”:”285026518″,”term_text”:”NM_003194.4″NM_003194.4). Triplicate of each sample was heated at 95?C for 5?min for denaturation, followed by 40?cycles of denaturation at 95?C for 15?s, annealing at 60?C for 60?s and extension at 60?C for 60?s. Reactions were performed in the Applied Biosystems 7500 Real-Time PCR System (Applied Biosystems, Ca, USA). Cycle threshold (Ct) was decided for the housekeeping gene (TBP) as well as target genes using the auto baseline and auto threshold conditions. Normalized gene expression data were made using Ct (Ct reference- Ct target) and the 2-Ct formula. Statistical analysis The data of the GEO datasets were presented as median with the maximum and minimum values or mean and standard deviation. Kolmogorov-Smirnov test was used to verify sample distribution. The analysis of nominal or categorized variables was performed using the chi-square test. To categorize a continuous or ordinal variable, we used the best cut-off point established using a ROC curve and the Youdens index [15]. For the in vitro data, test-T or ANOVA with post hoc Tukey method was used for analysis between groups. A and expression of AHR, CYP1A1, CYP1A2, and CYP1B1. According to Table?1, no correlation was observed between AHR expression.