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Purpose: Metastatic melanoma is a tumor amenable to immunotherapy in part due to the presence of antigen-specific tumor-infiltrating lymphocytes (TIL). These T cells can be activated and expanded for adoptive cell transfer (ACT), which has resulted in relatively high rates of clinical responses. Similarly, immune checkpoint inhibitors, specifically programmed cell death protein 1 (PD-1) blocking antibodies, augment antitumor immunity and increase the influx of T cells into tumors. Thus, we hypothesized that addition of PD-1 inhibition may improve the outcomes for patients undergoing ACT with TILs., Patients and Methods: Patients with stage III/IV metastatic melanoma with unresectable disease who were anti-PD-1 treatment-naïve were enrolled. TILs were generated in the presence of anti-4-1BB antibody in vitro and expanded for ACT. Patients in cohort 1 received TIL infusion followed by nivolumab. Patients in cohort 2 also received nivolumab prior to surgical harvest and during TIL production., Results: A total of 11 patients were enrolled, all of whom were evaluated for response, and nine completed ACT. Predominantly CD8+ TILs were successfully expanded from all ACT-treated patients and were tumor reactive in vitro. The trial met its safety endpoint, as there were no protocol-defined dose-limiting toxicity events. The objective response rate was 36%, and median progression-free survival was 5 months. Two nonresponders who developed new metastatic lesions were analyzed to determine potential mechanisms of therapeutic resistance, which included clonal divergence and intrinsic TIL dysfunction., Conclusions: Combination therapy with TILs and nivolumab was safe and feasible for patients with metastatic melanoma and provides important insights for future therapeutic developments in ACT with TILs., (©2022 American Association for Cancer Research.)

Despite numerous inquiries into protective roles of lycopene in prostate cancer prevention or therapy, little is known about mechanisms by which lycopene or its metabolites inhibit prostate cancer. The enzyme β-carotene 9',10'-oxygenase (BCO2), which catalyzes asymmetric cleavage of several carotenoids, is the principal regulator of lycopene metabolism, but the range of BCO2 biological functions is incompletely understood. This study investigated expression and functional roles of BCO2 in human prostate cancer. Expression of the bco2 gene is dramatically decreased in prostate cancer tissue and in a range of prostate cancer cell lines as compared with nonneoplastic prostate tissue and normal prostatic epithelial cells, respectively. Inhibition of DNA methyltransferase activity restored bco2 expression in prostate cancer cell lines tested. Treatment with lycopene or its metabolite, apo-10-lycopenal, also increased bco2 expression and reduced cell proliferation in androgen-sensitive cell lines, but lycopene neither altered bco2 expression nor cell growth in androgen-resistant cells. Notably, restoring bco2 expression in prostate cancer cells inhibited cell proliferation and colony formation, irrespective of lycopene exposure. Exogenous expression of either wild-type BCO2 or a mutant (enzymatically inactive) BCO2 in prostate cancer cells reduced NF-κB activity and decreased NF-κB nuclear translocation and DNA binding. Together, these results indicate epigenetic loss of BCO2 expression is associated with prostate cancer progression. Moreover, these findings describe previously unanticipated functions of BCO2 that are independent of its enzymatic role in lycopene metabolism., Implications: This study identifies BCO2 as a tumor suppressor in prostate cancer. BCO2-mediated inhibition of NF-κB signaling implies BCO2 status is important in prostate cancer progression. Mol Cancer Res; 14(10); 966-75. ©2016 AACR., (©2016 American Association for Cancer Research.)

The nicotine-derived tobacco-specific nitrosamine, 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone, is one of the most potent and abundant procarcinogens found in tobacco and tobacco smoke, and glucuronidation of its major metabolite, 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL), is an important mechanism for 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone detoxification. Substantial interindividual variability in urinary NNAL glucuronide formation has been observed in smokers and tobacco chewers. To determine whether genetic variations may play a role in this interindividual variability, NNAL-glucuronidating activities were analyzed in 78 human liver microsomal specimens and compared with the prevalence of missense polymorphisms in the two major NNAL-glucuronidating enzymes UGT1A4 and UGT2B7. In vitro assays using liver microsomal specimens from individual subjects demonstrated a 70- and 50-fold variability in NNAL-N-Gluc and NNAL-O-Gluc formation, respectively, and a 20-fold variability in the ratio of NNAL-N-Gluc:NNAL-O-Gluc formation. Microsomes from subjects with a homozygous polymorphic UGT1A4(24Thr)/UGT1A4(24Thr) genotype exhibited a significantly higher (P < 0.05) level of NNAL-N-Gluc activity compared with microsomes from subjects with the wild-type UGT1A4(24Pro)/UGT1A4(24Pro) genotype, and a significantly higher (P < 0.05) number of subjects with liver microsomes having high NNAL-N-Gluc formation activity contained the UGT1A4(24Thr)/UGT1A4(24Thr) genotype. Microsomes from subjects with the homozygous polymorphic UGT2B7(268Tyr)/UGT2B7(268Tyr) genotype exhibited a significantly lower level (P < 0.025) of NNAL-O-Gluc activity when compared with microsomes from subjects with the wild-type UGT2B7(268His)/UGT2B7(268His) genotype, and a significantly (P < 0.05) higher number of subjects with liver microsomes having low NNAL-O-Gluc formation activity contained the UGT2B7(268Tyr)/UGT2B7(268Tyr) genotype. These data suggest that the UGT1A4 codon 24 and UGT2B7 codon 268 polymorphisms may be associated with altered rates glucuronidation and detoxification of NNAL in vivo.

UDP-glucuronosyltransferase (UGT)-mediated glucuronidation of benzo(a)pyrene-trans-7,8-dihydrodiol (BPD), precursor to the potent mutagen benzo(a)pyrene-7,8-dihydrodiol-9,10-epoxide, may be an important pathway in the detoxification of benzo(a)pyrene. To better characterize this pathway in humans, high-pressure liquid chromatography (HPLC) was used to detect glucuronide conjugates of BPD formed in vitro. Three peaks were detected by HPLC after incubation of racemic BPD with human liver microsomes; these were identified as monoglucuronides by liquid chromatography-mass spectrometry analysis. Proton nuclear magnetic resonance spectroscopy of isolated fractions, combined with HPLC analysis of the glucuronide products from human liver microsomal incubations with purified benzo(a)pyrene-trans-7S,8S-dihydrodiol [(+)-BPD] and benzo(a)pyrene-trans-7R,8R-dihydrodiol [(-)-BPD] forms of BPD, indicated that peak 1 contained the 7-glucuronide of 7S,8S-BPD (BPD-7S-Gluc), peak 2 was a mixture of the 7-glucuronide of 7R,8R-BPD (BPD-7R-Gluc) and the 8-glucuronide of 7S,8S-BPD (BPD-8S-Gluc), and peak 3 contained the 8-glucuronide of 7R, 8R-BPD (BPD-8R-Gluc). In liver microsomes, peak 1 (BPD-7S-Gluc) was the largest peak observed, whereas in microsomes from aerodigestive tract tissues, peak 2 (both BPD-7R-Gluc and BPD-8S-Gluc) was the largest HPLC peak observed. The liver enzymes UGT1A1 and UGT2B7 formed BPD-7S-Gluc as the major diastereomer, whereas UGT1A8 and UGT1A10, extrahepatic enzymes present in the aerodigestive tract, preferentially formed both BPD-7R-Gluc and BPD-8S-Gluc. In addition, both UGT1A9 and UGT1A7 preferentially formed BPD-7R-Gluc. No detectable glucuronidating activity against BPD was observed by UGT1A3, UGT1A4, UGT1A6, UGT2B4, UGT2B15, or UGT2B17. The affinity of individual UGT enzymes as determined by K(m) analysis was UGT1A10 > UGT1A9 > UGT1A1 > UGT1A7 for (-)-BPD and UGT1A10 > UGT1A9 > UGT2B7 approximately UGT1A1 > UGT1A7 for (+)-BPD. These results suggest that several UGTs may play an important role in the overall glucuronidation of BPD in humans, with UGT1A1, UGT1A7, UGT1A9, UGT1A10 and potentially UGT1A8 playing an important role in the glucuronidation of the procarcinogenic (-)-BPD enantiomer, and that the stereospecific activity exhibited by different UGTs against BPD is consistent with tissue-specific patterns of BPD glucuronide diastereomer formation and UGT expression.