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Background: The phase I first-in-human study ENGAGE-1 evaluated the humanized IgG1 OX40 agonistic monoclonal antibody GSK3174998 alone (Part 1 (P1)) or in combination with pembrolizumab (Part 2 (P2)) in patients with advanced solid tumors., Methods: GSK3174998 (0.003-10 mg/kg) ± pembrolizumab (200 mg) was administered intravenously every 3 weeks using a continuous reassessment method for dose escalation. Primary objectives were safety and tolerability; secondary objectives included pharmacokinetics, immunogenicity, pharmacodynamics, and clinical activity., Results: 138 patients were enrolled (45 (P1) and 96 (P2, including 3 crossovers)). Treatment-related adverse events occurred in 51% (P1) and 64% (P2) of patients, fatigue being the most common (11% and 24%, respectively). No dose-toxicity relationship was observed, and maximum-tolerated dose was not reached. Dose-limiting toxicities (P2) included Grade 3 (G3) pleural effusion and G1 myocarditis with G3 increased troponin. GSK3174998 ≥0.3 mg/kg demonstrated pharmacokinetic linearity and >80% receptor occupancy on circulating T cells; 0.3 mg/kg was selected for further evaluation. Limited clinical activity was observed for GSK3174998 (P1: disease control rate (DCR) ≥24 weeks 9%) and was not greater than that expected for pembrolizumab alone (P2: overall response rate 8%, DCR ≥24 weeks 28%). Multiplexed immunofluorescence data from paired biopsies suggested that increased infiltration of natural killer (NK)/natural killer T (NKT) cells and decreased regulatory T cells (Tregs) in the tumor microenvironment may contribute to clinical responses: CD16+CD56-CD134+ NK /NKT cells and CD3+CD4+FOXP3+CD134+ Tregs exhibited the largest magnitude of change on treatment, whereas CD3+CD8+granzyme B+PD-1+CD134+ cytotoxic T cells were the least variable. Tumor gene expression profiling revealed an upregulation of inflammatory responses, T-cell proliferation, and NK cell function on treatment with some inflammatory cytokines upregulated in peripheral blood. However, target engagement, evidenced by pharmacologic activity in peripheral blood and tumor tissue, did not correlate with clinical efficacy. The low number of responses precluded identifying a robust biomarker signature predictive of response., Conclusions: GSK3174998±pembrolizumab was well tolerated over the dose range tested and demonstrated target engagement. Limited clinical activity does not support further development of GSK3174998±pembrolizumab in advanced cancers., Trial Registration Number: NCT02528357., Competing Interests: Competing interests: SP-V is a principal/subinvestigator of clinical trials for AbbVie, Adaptimmune, Adlai Nortye USA Inc, Aduro Biotech, Agios Pharmaceuticals, Amgen, Argenx BVBA, Arno Therapeutics, Astex Pharmaceuticals, AstraZeneca A, Aveo, Basilea Pharmaceutica International Ltd, Bayer Healthcare AG, BBB Technologies BV, Beigene, BicycleTx Ltd, Bioalliance Pharma, Blueprint Medicines, Boehringer Ingelheim, Boston Pharmaceuticals, Bristol Myers Squibb, Celgene Corporation, Chugai Pharmaceutical Co, Cullinan-Apollo, Curevarc, Daiichi Sankyo, Debiopharm, Eisai, Eisai Limited, Eli Lilly, Exelixis, Faron Pharmaceuticals Ltd, Forma Tharapeutics, GamaMabs, Genentech, GSK, H3 Biomedicine, Hoffmann La Roche AG, Imcheck Therapeutics, Innate Pharma, Institut De Recherche Pierre Fabre, Iris Servier, Iteos Belgium SA, Janssen Cilag, Janssen Research Foundation, Kura Oncology, Kyowa Kirin Pharm. Dev, Lilly France, Loxo Oncology, Lytix Biopharma AS, Medimmune, Menarini Ricerche, Merck Sharp & Dohme Chibret, Merus, Molecular Partners AG, Nanobiotix, Nektar Therapeutics, Novartis Pharma, Octimet Oncology NV, Oncoethix, Oncopeptides, Onyx Therapeutics, Orion Pharma, Oryzon Genomics, Ose Pharma, Pfizer, Pharma Mar, Pierre Fabre Medicament, Plexxikon, Roche, Sanofi Aventis, Seattle Genetics, Sotio A.S, Syros Pharmaceuticals, Taiho Pharma, Tesaro, Turning Point Therapeutics, and Xencor outside the submitted work; non-financial support (drug supplied) from AstraZeneca, Bayer, Bristol Myers Squibb, Boehringer Ingelheim, GSK, Medimmune, Merck, NH TherAGuiX, Pfizer, Roche; research funding from Boehringer Ingelheim, AstraZeneca, Roche, and Merck KGaA for projects unrelated to this manuscript. VL reports consulting for Takeda, Seattle Genetics, Bristol Myers Squibb, AstraZeneca, Guardant Health; research funding from GSK, Bristol Myers Squibb, Merck, Seattle Genetics. WR reports nothing to disclose. TMB reports consulting for Guardant Health, Loxo Pharmaceuticals, Pfizer, Exelixis, Blueprint Medicines, Foundation Medicine, Bayer, AstraZeneca, Ignyta, Moderna Therapeutics, Pfizer. Speakers Bureau: Bayer, Bristol Myers Squibb, and Lilly; research funding from Daiichi Sankyo, Medpacto, Inc., Incyte, Mirati Therapeutics, MedImmune, AbbVie, AstraZeneca, Leap Therapeutics, MabVax, Stemline Therapeutics, Merck, Lilly, GSK, Novartis, Pfizer, Genentech/Roche, Deciphera, Merrimack, Immunogen, Millennium Pharmaceuticals, Ignyta, Calithera Biosciences, Kolltan Pharmaceuticals, Principa Biopharma, Peleton, Immunocore, Aileron Therapeutics, Bristol Myers Squibb, Amgen, Moderna Therapeutics, Sanofi, Boehringer Ingelheim, Astellas Pharma, Five Prime Therapeutics, Jacobio, Top Alliance BioScience, Loxo, Janssen, Clovis Oncology, Takeda, Karyopharm Therapeutics, Onyx, Phosplatin Therapeutics, Foundation Medicine, and ARMO BioScience; personal expenses from Astellas Pharma, AstraZeneca, Celgene, Clovis Oncology, EMD Serono, Genentech, Lilly, Merck, Novartis, Pharmacyclics, Sysmex, and Pfizer. AHa reports research funding from Genentech/Roche, Merck, GSK, Bristol Myers Squibb, Novartis, Boston Biomedical, Boehringer Ingelheim, AstraZeneca/Medimmune Eisai; personal fees from Merck and GSK. DCC is a consultant for Nektar, Pfizer, Werewolf, and HUYA. FSH reports research funding from Bristol Myers Squibb and Novartis; receives personal fees from Bristol Myers Squibb, Merck, EMD Serono, Novartis, Surface, Compass Therapeutics, Apricity, Sanofi, Pionyr, Torque, Bicara, Checkpoint Therapeutics, Genentech/Roche, Bioentre, Gossamer, Iovance, Trillium, Catalym, Immunocore, Amgen, Kairos, Eisai, and Rheos. JHMS is a shareholder and part-time employee of Modra Pharmaceuticals BV and patent holder of oral taxanes; reports consulting for Debiopharm. JKL reports other from GSK, Novartis, Medivation/Pfizer, Genentech, EMD-Serono, AstraZeneca, Medimmune, Zenith, Ayala, UpToDate review panels for NCCN, ASCO, NIH PDQ, Medlearning, Physicians Education Resource, Prime Oncology, Medscape, Clinical Care Options, Medpage. SA reports advisory board participation for MSD, Sanofi, Roche, Bristol Myers Squibb, Pfizer; research support from Sanofi. KAA reports research funding (to institution) from Pfizer, AstraZeneca, Amgen, Trishula, GSK, Merck, and Eli Lilly. FO is a principal/subinvestigator of clinical trials for Amgen, AstraZeneca, Cytovation, GSK, Lilly, MSD, Revmed, Incyte, Boehringer Ingelheim, Bristol Myers Squibb, Roche/Genentech, Exelexis, Relay, and InterRNA. MM reports research funding from Alpine Immune Sciences, Arcus Biosciences, Arvinas, Ascentage Pharma Group, Bayer, Bicycle Therapeutics, BioMed Valley Discoveries, BioNTech, Dragonfly Therapeutics, EMD Serono, Epizyme, Erasca, Exelixis, Foghorn Therapeutics, Genentech, Gilead Sciences, GSK, IDEAYA Biosciences, Ikena Oncology, ImmVira Pharma, Infinity Pharmaceuticals, Jacobio Pharmaceuticals, Kechow Pharma, Kezar Life Sciences, Kinnate BioPharma, MedImmune, Mereo BioPharma, Metabomed, Moderna, NBE Therapeutics, Nektar, Novartis, Oncorus, PACT Pharma, Pfizer, Plexxikon, Prelude Therapeutics, Pyramid Biosciences, Regeneron, Sapience Therapeutics, Scholar Rock Seattle Genetics, Synthrox, Takeda Pharmaceuticals, Teneobio, Tempest Therapeutics, Tizona Therapeutics, TMUNITY Therapeutics, TopAlliance Biosciences, and Xilio. M; consulting/advisory role for Astellas Pharma, AstraZeneca, BicycleTX Limited, Castle Biosciences, Eisai, Ideaya Biosciences, iTeos, Pfizer, and Regeneron Pharmaceuticals. NS reports consulting/advisory role for Deciphera, AADi, Blueprint Medicines, Bayer, Epizyme, and Boehringer Ingelheim; research funding from GSK, Karyopharm, Deciphera, Ascentage Pharma, Daiichi Sankyo/Lilly, and AstraZeneca/MedImmune. SC is the principal/subinvestigator of clinical trials for AbbVie, Adaptimmune, Adlai Nortye USA Inc, Aduro Biotech, Agios Pharmaceuticals, Amgen, Astex Pharmaceuticals, AstraZeneca AB, Aveo, Basilea Pharmaceutica International Ltd, Bayer Healthcare AG, BBB Technologies BV, Beigene, BicycleTx Ltd, Blueprint Medicines, Boehringer Ingelheim, Boston Pharmaceuticals, Bristol Myers Squibb, Casi Pharmaceuticals, Inc, Celgene Corporation (a Bristol-Myers Squibb company), Cellcentric, Chugai Pharmaceutical Co, Cullinan-Apollo, Curevarc, Cytovasion, Daiichi Sankyo, Debiopharm, Eisai, Eli Lilly, Exelixis, Faron Pharmaceuticals Ltd, Forma Tharapeutics, GamaMabs, Genentech, GSK, H3 Biomedicine, Hoffmann La Roche AG, Imcheck Therapeutics, Incyte Corporation, Innate Pharma, Institut De Recherche Pierre Fabre, Iris Servier, Iteos Belgium SA, Janssen Cilag, Janssen Research Foundation, Janssen R&D LLC, Kura Oncology, Kyowa Kirin Pharm. Dev, Lilly France, Loxo Oncology, Medimmune, Menarini Ricerche, Merck, Merck Sharp & Dohme Chibret, Merrimack Pharmaceuticals, Merus, Molecular Partners AG, Nanobiotix, Nektar Therapeutics, Novartis Pharma, Octimet Oncology NV, Oncoethix, Oncopeptides, Orion Pharma, Genomics, Ose Pharma, Pfizer, Pharma Mar, Pierre Fabre Medicament, Relay Therapeutics, Inc, Roche, Sanofi Aventis, Seattle Genetics, Sotio, Syros Pharmaceuticals, Taiho Pharma, Tesaro, Transgene SA, Turning Point Therapeutics, and Xencor; reports research grants from AstraZeneca, Bristol Myers Squibb, Boehringer Ingelheim, GSK, INCA, Janssen Cilag, Merck, Pfizer, Roche, and Sanofi; reports non-financial support (drug supplied) from AstraZeneca, Bristol Myers Squibb, Boehringer Ingelheim, GSK, Medimmune, Merck, NH TherAGuiX, Pfizer, and Roche; reports honoraria from Amgen, Astellas, AstraZeneca, Bristol Myers Squibb, Eisai, Genmab, Janssen, Merck, Novartis and Roche; reports participation in advisory boards for Alderaan Biotechnology, Amgen, AstraZeneca, Avacta, Ellipses Pharma, Oncovita, Seagen, UltraHuman8; reports travel and congress support from AstraZeneca, Bristol Myers Squibb, Merck, Ose Pharma, Roche, Sotio. MA reports research funding (to institution) from Genentech, Nektar Therapeutics, Merck, GSK, Novartis, Jounce Therapeutics, Bristol Myers Squibb, Eli Lilly, Adaptimmune, Shattuck Lab, and Gilead. Advisory boards: GSK, Shattuck Lab, Bristol Myers Squibb, AstraZeneca; reports speaker fees from AstraZeneca, and Nektar Therapeutics. AS reports participation in advisory boards for Merck, Bristol Myers Squibb, Novartis, Oncorus, Janssen, Medison, and Immunocore; reports research support: Novartis, Bristol Myers Squibb, Symphogen AstraZeneca/Medimmune, Merck, Bayer, Surface Oncology, Northern Biologics, Janssen Oncology/Johnson & Johnson, Roche, Regeneron, Alkermes, Array Biopharma/Pfizer, GSK, Treadwell, and Amgen. OR reports employment with AstraZeneca; reports research funding from Merck; reports speaker for activities supported by educational grants from Bristol Myers Squibb and Merck; reports consulting for Merck, Celgene, Five Prime, GSK, Bayer, Roche/Genentech, Puretech, Imvax, Sobi, Boehringer Ingelheim; reports pending patent for “Methods of using pembrolizumab and trebananib”. EMP, CMA, HZ, HS, SAG, MW, KMY, NY, and AHo report employment with GSK. MJC is an employee of Merck and owns stock. EVS is an employee of Merck. AM has been a principal or coinvestigator of clinical trials using OX40-targeted agents and/or has provided consulting services for Roche/Genentech, AstraZeneca, Pfizer, GSK, HiFiBiO, Bristol Myers Squibb, Shattuck Labs. JW reports consulting for Merck, Genentech, AstraZeneca, GSK, Novartis, Nektar, Celldex, Incyte, Biond, ImCheck, Sellas, Evaxion and EMD Serono; reports participation in advisory boards for Bristol Myers Squibb (compensated), CytoMx, Incyte, ImCheck, Biond, Sellas, Instil Bio, OncoC4, and Neximmune; reports equity holdings in Biond, Evaxion, Instil Bio, OncoC4, and Neximmune; reports research support (to institution) from Bristol Myers Squibb, Merck, GSK, Moderna, Pfizer, Novartis, and AstraZeneca, Moffitt Cancer Center; reports patent for ipilimumab biomarker and tumor-infiltrating lymphocytes preparation and a PD-1 patent (Biodesix). JVH reports other from GSK, AstraZeneca, Checkmate Pharmaceuticals, Brightpath Biotherapeutics, Eli Lilly & Co, Kairos Venture Investments, Triptych Health Partners; reports patent with Spectrum Pharmaceuticals., (© Author(s) (or their employer(s)) 2023. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Belantamab mafodotin (belamaf) is a BCMA-targeted antibody-drug conjugate recently approved as monotherapy for adults with relapsed/refractory multiple myeloma who have received ≥4 prior therapies. Belamaf binds to BCMA and eliminates myeloma cells by multimodal mechanisms of action. The cytotoxic and potential immunomodulatory properties of belamaf have led to novel combination studies with other anticancer therapies. Here, we describe the rationale and design of DREAMM-5, an ongoing Phase I/II platform study evaluating the safety and efficacy of belamaf combined with novel agents, including GSK3174998 (OX40 agonist), feladilimab (an ICOS; GSK3359609), nirogacestat (a gamma-secretase inhibitor; PF-03084014) and dostarlimab (a PD-1 blocker) versus belamaf monotherapy for patients with relapsed/refractory multiple myeloma. Clinical trial registration: NCT04126200 (ClinicalTrials.gov).

Purpose: The study evaluated the safety, tolerability, and pharmacokinetics of BMS-936561, a fully human monoclonal antibody-drug conjugate targeting CD70 cell-surface protein., Methods: Eligible patients had ECOG performance status 0-2 and received ≤3 prior chemotherapy regimens. An initial accelerated titration design enrolling one patient per dose level was followed by 3 + 3 dose escalation with the first observation of a grade ≥2 adverse event (AE). We tested escalating doses of BMS-936561 (0.5, 1, 2, 4, 8, 15 mg/kg) administered every 21 days in a 42 day cycle for a maximum of 17 cycles. Pharmacokinetic samples were collected in cycle 1., Results: A total of 26 patients enrolled; 16 and 10 for the escalation and expansion cohorts, respectively. Median age was 63 years (48-74); 18 males and 25 Caucasians. There was no defined MTD per protocol, but a DLT of grade 3 hypersensitivity was recorded in 2 of 16 (13%) subjects at the highest dose of 15 mg/kg. The most frequent AEs were: fatigue (85%), nausea (54%), and decreased appetite (39%). Delayed toxicities (facial edema and pleural/pericardial effusions) occurred in 6 of 16 (38%) subjects at the 15 mg/kg dose. PK analysis showed a dose-proportional increase in active drug levels with increasing doses. There was disease stabilization in 18 of 26 patients (69%) without correlation with received dose., Conclusions: BMS-936561 is well tolerated over a wide range of doses in patients with advanced ccRCC and B-NHL. The 8 mg/kg dose was the highest best tolerated dose and the recommended dose for future studies.

Purpose: Programmed death 1 is an immune checkpoint that suppresses antitumor immunity. Nivolumab, a fully human immunoglobulin G4 programmed death 1 immune checkpoint inhibitor antibody, was active and generally well tolerated in patients with advanced solid tumors treated in a phase I trial with expansion cohorts. We report overall survival (OS), response durability, and long-term safety in patients with non-small-cell lung cancer (NSCLC) receiving nivolumab in this trial., Patients and Methods: Patients (N = 129) with heavily pretreated advanced NSCLC received nivolumab 1, 3, or 10 mg/kg intravenously once every 2 weeks in 8-week cycles for up to 96 weeks. Tumor burden was assessed by RECIST (version 1.0) after each cycle., Results: Median OS across doses was 9.9 months; 1-, 2-, and 3-year OS rates were 42%, 24%, and 18%, respectively, across doses and 56%, 42%, and 27%, respectively, at the 3-mg/kg dose (n = 37) chosen for further clinical development. Among 22 patients (17%) with objective responses, estimated median response duration was 17.0 months. An additional six patients (5%) had unconventional immune-pattern responses. Response rates were similar in squamous and nonsquamous NSCLC. Eighteen responding patients discontinued nivolumab for reasons other than progressive disease; nine (50%) of those had responses lasting > 9 months after their last dose. Grade 3 to 4 treatment-related adverse events occurred in 14% of patients. Three treatment-related deaths (2% of patients) occurred, each associated with pneumonitis., Conclusion: Nivolumab monotherapy produced durable responses and encouraging survival rates in patients with heavily pretreated NSCLC. Randomized clinical trials with nivolumab in advanced NSCLC are ongoing., (© 2015 by American Society of Clinical Oncology.)

Background The folate receptor alpha is selectively over-expressed in a number of human cancers. BMS-753493 is a folate conjugate of the epothilone analog BMS-748285 that was designed to selectively target folate receptor expressing cancer cells. Methods BMS-753493 was investigated in two parallel multi-institutional first-in-human phase I/IIa studies in patients with advanced solid tumors. In Study 1, patients were treated on a schedule of once daily dosing of BMS-753493 administered on Days 1, 4, 8 and 11 every 21 days with a starting dose of 5 mg daily and in Study 2, patients were treated once daily on Days 1-4 every 21 days, with a starting dose of 2.5 mg daily. Results A total of 65 patients were treated across the two studies. The maximum tolerated dose (MTD) was 26 mg in Study 1 and 15 mg in Study 2. Fatigue, transaminitis, gastrointestinal toxicity, and mucositis were dose-limiting toxicities. One patient in Study 2 developed Stevens-Johnson syndrome attributed to BMS-753493. Plasma exposures of both the conjugated and free epothilone increased in a dose related fashion in both studies and the half-life of the conjugated epothilone was 0.2-0.6 h across dose levels. No objective tumor responses were seen in either study. Conclusions BMS-753493 was generally tolerable and toxicities known to be associated with epothilone class of anticancer agents were common, although peripheral neuropathy and neutropenia appear to have been less frequent and less severe as compared to epothilones. Antitumor activity was not demonstrated and further development of BMS-753493 has been discontinued.

Background: Intravenous infusion of ixabepilone is Food and Drug Administration-approved for treatment of patients with metastatic breast cancer. The aim of this study was to establish the maximum tolerated dose (MTD), dose-limiting toxicities (DLTs), safety, and pharmacokinetics (PK) of a novel oral formulation of ixabepilone in patients with advanced solid tumors., Patients and Methods: Forty-four patients received one of six daily doses of oral ixabepilone (5, 10, 15, 20, 25, or 30 mg) on days 1-5 of a 21-day cycle. PK parameters were evaluated in cycle 1 for all treated patients and in cycle 1 and cycle 2 for patients participating in assessments of food and gastric pH effects., Results: The most common DLTs (reported in at least one patient) were neutropenia, neutropenic fever, diarrhea, ileus, and hypokalemia. The MTD of oral ixabepilone was 25 mg. Plasma concentrations of ixabepilone showed high variability; coefficients of variation for the area under the curve and the peak plasma concentration ranged from 61 to 131 % and from 17 to 172 %, respectively. The mean half-life of ixabepilone calculated after day 5 of cycle 1 ranged from 24 to 47 h. Ixabepilone exposure was higher when administered with a low-fat meal compared with the fasted state, and when administered 2 h after the histamine H2 receptor antagonist famotidine., Conclusions: The MTD of oral ixabepilone when administered once daily for five consecutive days every 21 days was 25 mg. Ixabepilone exposure was highly variable; therefore, safety and efficacy of this novel oral formulation might not be reliably predicted.

BMS-690514, a selective inhibitor of the ErbB and vascular endothelial growth factor receptors, has shown antitumor activity in early clinical development. The compound is metabolized by multiple enzymes, with CYP3A4 responsible for the largest fraction (34%) of metabolism. It is also a substrate of P-glycoprotein (P-gp) in vitro. To assess the effect of ketoconazole on BMS-690514 pharmacokinetics, 17 healthy volunteers received 200 mg BMS-690514 alone followed by 100 mg BMS-690514 with ketoconazole (400 mg once daily for 4 days). The AUC(∞) of 100 mg BMS-690514 concomitantly administered with ketoconazole was similar to that of 200 mg BMS-690514 alone. The dose-normalized C(max) and AUC(∞) of BMS-690514 from the 100-mg BMS-690514/400-mg ketoconazole treatment increased by 55% and 127%, respectively, relative to those from 200 mg BMS-690514 alone. Prediction of the drug-drug interaction (DDI) using a population-based simulator (Simcyp) indicated that, in addition to CYP3A4 inhibition, the inhibition of P-gp by ketoconazole in the intestine, liver, and kidneys must be invoked to fully account for the DDI observed. This finding suggests that the inhibition of P-gp by ketoconazole, along with its effect on CYP3A4, needs to be considered when designing a DDI study of ketoconazole with a victim drug that is a dual substrate., (© The Author(s) 2012.)

We studied the effect of food on pharmacokinetics, safety, and tolerability of BMS-690514. Two open-label, randomized, single-dose, 2-treatment, 2-period crossover studies were performed in healthy subjects. In study 1 (N = 26), a single oral dose of BMS-690514, 200 mg, was administered while fasting or after a high-fat meal, and in study 2 (N = 17), a single oral dose of BMS-690514, 200 mg, was administered while fasting or after a light meal. Compared with fasting, the adjusted geometric mean maximum observed plasma concentration (C(max)), area under the plasma concentration-time curve from time zero to time of last quantifiable concentration (AUC(0-T)), area under the plasma concentration-time curve from time zero extrapolated to infinite time (AUC(INF)) of BMS-690514 increased by 55%, 33%, and 34%, respectively, following a high-fat meal (951 kcal, 52% fat) and by 41%, 20%, and 20%, respectively, following a light meal (336 kcal, 75% carbohydrate). BMS-690514 was well tolerated in both studies. Most frequently occurring adverse events were diarrhea and acne in study 1 and rash, dry skin, and diarrhea in study 2. Systemic exposure of highly soluble BMS-690514 was increased when given along with a meal, probably through inhibition of intestinal first-pass metabolism and/or efflux transporters by food. These studies also demonstrated a tolerable safety profile of BMS-690514 in the absence and presence of food.

Objective: To determine if the C421A single nucleotide polymorphism (SNP) in the ATP-binding cassette transporter ABCG2 increases prostate cancer risk or affects survival., Patients, Subjects and Methods: Numerous studies have suggested that dietary, hormonal and environmental factors all play a role in the initiation in prostate cancer; among these, the carcinogenic heterocyclic amine 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP), a known substrate of the ABCG2. A SNP of ABCG2, C421A, resulting in a glutamine to lysine change at amino acid 141, has been shown to result in decreased function of the protein. Due to the expression of ABCG2 in the prostate, together with the purported role of dietary carcinogens and steroids in the development and progression of prostate cancer, 311 individuals were genotyped for the ABCG2 C421A SNP, 170 patients with androgen-independent prostate cancer (AIPC) and 141 'healthy' controls. We also evaluated the effect of this SNP on the intracellular accumulation of PhIP and testosterone in vitro., Results: There were no significant differences in the prevalence of prostate cancer based on ABCG2 genetic variation in this population. However, survival was significantly longer for individuals with wild-type ABCG2, as compared with those hetero- or homozygous for the C421A SNP (7.4 years vs 5.3 years, P = 0.044). Intracellular accumulation of PhIP was 80% higher in HEK293 cells transfected with Q141K ABCG2 than in wild-type cells, confirming that this SNP decreases transport of PhIP. In contrast, testosterone was not transported by either wild-type or variant transfected cells, nor did it act as in inhibitor of ABCG2 in subsequent transport assays., Conclusion: Increased exposure to PhIP may decrease survival, but the ABCG2 C421A polymorphism does not appear to increase the risk of prostate cancer.

Genes playing a role in carcinogenesis have often been identified through analysis of recurrent chromosomal rearrangements. Although such rearrangements are well known in leukemias, lymphomas, and sarcomas, they have not been well characterized in carcinomas. In the October 28, 2005 issue of Science, a study by Tomlins et al. uses bioinformatics techniques to identify candidate oncogenic chromosomal changes based on analysis of outlier gene expression. The authors determined that two ETS transcription factors, ERG and ETV1 were outliers in prostate cancer. The group reports recurrent fusions of the 5' untranslated region of the TMPRSS2 gene to ERG and ETV1 in the majority of prostate cancer samples containing the outlier expression. In cell lines containing the fusion gene, androgen appears to play a role in mediating ETS overexpression. This fusion gene product may play an important role in the development, diagnosis, and treatment of prostate cancer.

Interleukin-6 (IL-6) may be important in the pathogenesis of HIV-1 because of its ability to induce HIV-1 expression in infected cells in vitro. Tenidap, a structurally and functionally novel antirheumatic drug affecting diverse biologic processes, has been shown to reduce IL-6 production by peripheral blood mononuclear cells stimulated with lipopolysaccharide. Tenidap also inhibits the activity of chloride-bicarbonate exchangers and causes acidification of the cytoplasmic compartment that is similar to the effect of the anion transport inhibitor UK5099. Furthermore, tenidap inhibits the cyclooxygenase-mediated pathway of arachidonic acid metabolism as do the nonsteroidal antiinflammatory drugs (NSAIDs). Here we show that tenidap decreased HIV-1 replication as measured by p24 core antigen in the acutely infected CD4+ T-lymphocyte lines H9 and Jurkat, in the acutely infected monocyte line U937, and in its chronically infected subclone U1.8/HIV. These effects were seen at concentrations in the range of 3 to 15 microM, well below those toxic to cells. The antiviral effects of tenidap may be independent of its ability to reduce IL-6 production based on the observations that these effects were as prominent in IL-6 nonresponsive lines as in IL-6 responsive lines and that the inhibition of p24 production was not reversed by exogenous IL-6.

The virus-encoded Tat protein strongly activates transcription of human immunodeficiency virus (HIV). A well-recognized mechanism involves interaction of Tat with the nascent RNA transcript of the viral tar gene; mutation of tar greatly decreases activation by Tat. However, Tat still provides a low level of activation, demonstrating that it also has a tar-independent mode of action. We propose that this tar-independent mode of Tat action is through activation of gene transcription to produce tumor necrosis factor alpha. This cytokine and other compounds that activate NF-kappa B up-regulate the HIV promoter at a low level, similarly to the second Tat action. Through this mechanism, they also activate promoters of tumor necrosis factor alpha and other cytokines and thereby establish an auto-up-regulatory loop. Activated NF-kappa B motifs in the HIV promoter synergize with Tat/tar. Mutations of these motifs decrease activation by Tat to a few percent of the wild-type value. In cooperation, the two modes of activation by Tat (tar dependent and cytokine based) set up positive up-regulatory loops which greatly superactivate transcription of HIV. Agents that block these synergistic pathways at three different steps and are more inhibitory in combination than is any one alone have been found. Thereby, multidrug modalities for transcription of HIV are proposed for virus suppression.

Tumor necrosis factor-alpha (TNF) may activate human immunodeficiency virus (HIV), antagonize zidovudine activity, and contribute to AIDS wasting syndrome. Pentoxifylline decreases TNF production. In cell culture, pentoxifylline decreases HIV replication and gene expression. Since an AIDS Clinical Trial Group study suggested that pentoxifylline (400 mg thrice daily) is safe in AIDS patients and decreases TNF mRNA levels in peripheral blood mononuclear cells (PBMC), a second cohort received 800 mg thrice daily for 8 weeks. During treatment, the median decrease in TNF production by PBMC cultured with 0.1 microgram/mL lipopolysaccharide (LPS) was 40%. The median change in TNF mRNA was a 34% decrease. Pentoxifylline did not affect HIV levels as detected by quantitative microculture or serum p24 antigen measurements, nor did it alter zidovudine pharmacokinetics. The most common toxicity was gastrointestinal. Pentoxifylline at dosages of less than thrice-daily 800 mg is well tolerated and may decrease TNF mRNA levels and LPS-induced TNF production.

Background: This investigation deals with the molecular mechanism of anti-human immunodeficiency virus type 1 (HIV-1) action of pentoxifylline (PTX) [1-(5'-oxohexyl)-3, 7-dimethylxanthine] a drug widely used for the treatment of conditions involving defective regional microcirculation., Materials and Methods: The inhibition by PTX of protein kinase C (PKC) or cAMP-dependent protein kinase (PKA)-mediated activation by phorbol ester (PMA) and tumor necrosis factor alpha (TNF-alpha) of HIV-1-LTR-regulated reporter gene expression was studied in human CD4+ T lymphocytes (Jurkat) and human embryo kidney cells (293-27-2). A protein kinase C is involved in activation of NF-kappa B in whole cells, identified by using inhibitors specific for PKC- or PKA-catalyzed NF-kappa B activation in whole cell and cell-free systems., Results: PTX inhibited PKC- or PKA-catalyzed activation of NF-kappa B in cytoplasmic extracts from unstimulated Jurkat or 293-27-2 cells, but not interaction of preactivated NF-kappa B with its motifs. Calphostin C, a specific inhibitor of PKC, inhibited NF-kappa B activation and HIV-1 LTR-driven reporter gene expression in both PMA- and TNF-alpha-treated cells. In contrast, although H88 specifically inhibited PKA activity in the cell-free extract, it did not affect NF-kappa B action in PMA- or TNF-alpha-treated cells., Conclusions: The mechanism of inhibitory action of PTX on virus replication and NF-kappa B-induced transactivation of HIV-1 gene expression has been elucidated as due to blocking PKC-dependent PMA- or TNF-alpha-induced activation of NF-kappa B in Jurkat and 293-27-2 cells. Other protein kinase inhibitors may be useful in down regulating transcription of HIV-1 provirus and thereby virus replication in HIV-infected patients.

No curative drug against HIV has yet been found, despite enormous efforts aimed at reverse transcriptase and a variety of other targets. The long terminal repeat (LTR) of HIV-1 has recently become a promising site for antiviral action. This article briefly summarizes information on the nature of this target and potential anti-LTR expression drugs.

Human immunodeficiency virus type 1 (HIV-1) long terminal repeat (LTR)-regulated gene expression is stimulated independently by the cellular trans-activator NF-kappa B and the viral protein Tat. Noncytotoxic concentrations of the drug pentoxifylline (PTX) inhibited interaction of NF-kappa B with its motif and the stimulation of HIV-1 LTR-driven gene expression in Jurkat cells. Tat protein (from a cotransfected Tat-expression vector) also induced activation of HIV-1 LTR-driven gene expression. This activation was unaffected by PTX when NF-kappa B sites in the HIV-1 LTR were mutated, suggesting that this drug does not directly influence Tat function, which, however, was inhibited by the Tat-inhibitor Ro 24-7429. Transient reporter gene expression regulated by HIV-1 LTR with wild-type NF-kappa B motifs in the presence of Tat protein was 10- to 60-fold higher than in the presence of either of the trans-activators alone, demonstrating superactivation of HIV-1 LTR by the concerted action of both the trans-activators. Treatment of cells with either PTX or Ro 24-7429 inhibited this superactivation of the HIV-1 LTR. The inhibitory effect of these two drugs in combination, at concentrations that alone did not significantly influence viral promoter activity, was far more than additive. A cooperative action of PTX (NF-kappa B inhibitor) and Ro 24-7429 (Tat inhibitor) on HIV-1 LTR-regulated gene expression is suggested. Concentrations of the drugs that induced maximum inhibition of HIV-1 LTR through their cooperative action are far below cytotoxic levels. Thus, the combination of these two inhibitors could be very effective for anti-HIV therapy.

The drug pentoxifylline (PTX) (1-(5'-oxohexyl) 3,7-dimethylxanthine) down-regulates human immunodeficiency virus (HIV-1) long terminal repeat (LTR)-directed gene expression in the human monocytic cell line U38. This effect of PTX has been tested in clinical trials. In this investigation, a similar inhibitory effect of PTX on HIV-1 LTR-driven gene expression was observed (a) in a stable transfectant of the human embryo kidney cell line 293-27-2 carrying an expression plasmid construct with the HIV-1 LTR fused to the bacterial lac Z gene, and also (b) by transient transfection of human embryo kidney cells 293 S with fusion plasmid constructs with wild-type [pHIV-LTR-chloramphenicol acetyltransferase (CAT)] or mutated (pHIV-LTR-mut-CAT) nuclear factor kappa B (NF-kappa B) motifs. In both stable and transient transfection studies, 4-beta-phorbol-12-beta-myristate-acetate (PMA)-induced or tumor necrosis factor-alpha (TNF-alpha)-induced activation of the HIV-1 LTR was correlated with a concomitant elevated level of NF-kappa B interaction with its motifs. The inducibility of HIV-1 LTR-driven gene expression by PMA or TNF-alpha in transiently transfected cells was completely eliminated by point mutations in the NF-kappa B motifs, suggesting that NF-kappa B plays a major role in the activation of the HIV-1 LTR by these agents in this cell system.(ABSTRACT TRUNCATED AT 250 WORDS)

Tumor necrosis factor-alpha (TNF)-cachectin increases the expression of the human immunodeficiency virus (HIV), reverses the therapeutic efficacy of zidovudine (ZDV), and may contribute to the wasting syndrome. Pentoxifylline (Trental) decreases TNF activity; in cell culture, it decreases HIV replication and down-regulates expression of the HIV long terminal repeat (LTR). Therefore, pentoxifylline was administered to 25 patients with advanced AIDS in this AIDS Clinical Trial Group study (ACTG #160), the goal of which was to investigate the ability of the drug to decrease TNF expression and HIV replication in this patient population. One patient discontinued drug treatment because of toxicity. Data were analyzed on the 17 patients who completed the 8-week study treatment with pentoxifylline, 400 mg, thrice daily. The median pretreatment CD4+ lymphocyte count was 32 cells/mm3. Fasting serum triglycerides, which have previously been shown to correlate with levels of interferon-alpha and/or TNF, fell on average by 66 mg/dl (p = 0.06). TNF mRNA levels in peripheral blood mononuclear cells fell in 10 of 16 patients (p = 0.02). HIV load decreased and increased significantly in four and one patients, respectively, but did not change in the group as a whole. This study demonstrates the safety of pentoxifylline in AIDS patients and its ability to decrease triglycerides and TNF mRNA levels.

The human immunodeficiency virus establishes an intimate interaction with the immune system. The virus can use cytokines, such as tumor necrosis factor-alpha (TNF-alpha) and interleukin-1 (Il-1), to regulate its own expression by modifying the normal immunoregulatory network. We demonstrate that mRNA of the cytokine TNF-alpha from peripheral blood mononuclear cells is overexpressed in virtually all patients with AIDS who do not have active opportunistic infections compared with uninfected volunteers (p < 0.0001). This overexpression correlates with elevated mRNA levels of the recently discovered GRO (p < 0.05), a cytokine involved in the inflammatory response.