1
|
Garcia PL, Miller AL, Kreitzburg KM, Council LN, Gamblin TL, Christein JD, Heslin MJ, Arnoletti JP, Richardson JH, Chen D, Hanna CA, Cramer SL, Yang ES, Qi J, Bradner JE, Yoon KJ. The BET bromodomain inhibitor JQ1 suppresses growth of pancreatic ductal adenocarcinoma in patient-derived xenograft models. Oncogene 2015; 35:833-45. [PMID: 25961927 DOI: 10.1038/onc.2015.126] [Citation(s) in RCA: 100] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2015] [Revised: 03/04/2015] [Accepted: 03/16/2015] [Indexed: 12/23/2022]
Abstract
The primary aim of this study was to evaluate the antitumor efficacy of the bromodomain inhibitor JQ1 in pancreatic ductal adenocarcinoma (PDAC) patient-derived xenograft (tumorgraft) models. A secondary aim of the study was to evaluate whether JQ1 decreases expression of the oncogene c-Myc in PDAC tumors, as has been reported for other tumor types. We used five PDAC tumorgraft models that retain specific characteristics of tumors of origin to evaluate the antitumor efficacy of JQ1. Tumor-bearing mice were treated with JQ1 (50 mg/kg daily for 21 or 28 days). Expression analyses were performed with tumors harvested from host mice after treatment with JQ1 or vehicle control. An nCounter PanCancer Pathways Panel (NanoString Technologies) of 230 cancer-related genes was used to identify gene products affected by JQ1. Quantitative RT-PCR, immunohistochemistry and immunoblots were carried out to confirm that changes in RNA expression reflected changes in protein expression. JQ1 inhibited the growth of all five tumorgraft models (P<0.05), each of which harbors a KRAS mutation; but induced no consistent change in expression of c-Myc protein. Expression profiling identified CDC25B, a regulator of cell cycle progression, as one of the three RNA species (TIMP3, LMO2 and CDC25B) downregulated by JQ1 (P<0.05). Inhibition of tumor progression was more closely related to decreased expression of nuclear CDC25B than to changes in c-Myc expression. JQ1 and other agents that inhibit the function of proteins with bromodomains merit further investigation for treating PDAC tumors. Work is ongoing in our laboratory to identify effective drug combinations that include JQ1.
Collapse
Affiliation(s)
- P L Garcia
- Department of Pharmacology and Toxicology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - A L Miller
- Department of Pharmacology and Toxicology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - K M Kreitzburg
- Department of Pharmacology and Toxicology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - L N Council
- Division of Anatomic Pathology, Department of Pathology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - T L Gamblin
- Department of Pharmacology and Toxicology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - J D Christein
- Division of General Surgery, Gastrointestinal Surgery or Surgical Oncology, Department of Surgery, University of Alabama at Birmingham, Birmingham, AL, USA
| | - M J Heslin
- Division of General Surgery, Gastrointestinal Surgery or Surgical Oncology, Department of Surgery, University of Alabama at Birmingham, Birmingham, AL, USA
| | - J P Arnoletti
- Division of General Surgery, Gastrointestinal Surgery or Surgical Oncology, Department of Surgery, University of Alabama at Birmingham, Birmingham, AL, USA
| | - J H Richardson
- Division of General Surgery, Gastrointestinal Surgery or Surgical Oncology, Department of Surgery, University of Alabama at Birmingham, Birmingham, AL, USA
| | - D Chen
- Division of Preventive Medicine, Department of Medicine, University of Alabama at Birmingham, Birmingham, AL, USA
| | - C A Hanna
- Division of Anatomic Pathology, Department of Pathology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - S L Cramer
- Department of Pediatrics, University of Alabama at Birmingham, Birmingham, AL, USA
| | - E S Yang
- Department of Radiation Oncology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - J Qi
- Department of Medical Oncology, Dana Farber Cancer Institute, Boston, MA, USA
| | - J E Bradner
- Department of Medical Oncology, Dana Farber Cancer Institute, Boston, MA, USA
| | - K J Yoon
- Department of Pharmacology and Toxicology, University of Alabama at Birmingham, Birmingham, AL, USA
| |
Collapse
|
2
|
Adams MR, Hanna CA, Mayernik JA, Mendez WM. Probabilistic health risk assessment for exposures to estuary sediments and biota contaminated with polychlorinated biphenyls, polychlorinated terphenyls and other toxic substances. Risk Anal 1994; 14:577-594. [PMID: 7972959 DOI: 10.1111/j.1539-6924.1994.tb00272.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
A Latin Hypercube probabilistic risk assessment methodology was employed in the assessment of health risks associated with exposures to contaminated sediment and biota in an estuary in the Tidewater region of Virginia. The primary contaminants were polychlorinated biphenyls (PCBs), polychlorinated terphenyls (PCTs), polynuclear aromatic hydrocarbons (PAHs), and metals released into the estuary from a storm sewer system. The exposure pathways associated with the highest contaminant intake and risks were dermal contact with contaminated sediment and ingestion of contaminated aquatic and terrestrial biota from the contaminated area. As expected, all of the output probability distributions of risk were highly skewed, and the ratios of the expected value (mean) to median risk estimates ranged from 1.4 to 14.8 for the various exposed populations. The 99th percentile risk estimates were as much as two orders of magnitude above the mean risk estimates. For the sediment exposure pathways, the stability of the median risk estimates was found to be much greater than the stability of the expected value risk estimates. The interrun variability in the median risk estimate was found to be +/- 1.9% at 3000 iterations. The interrun stability of the mean risk estimates was found to be approximately equal to that of the 95th percentile estimates at any number of iterations. The variation in neither contaminant concentrations nor any other single input variable contributed disproportionately to the overall simulation variance. The inclusion or exclusion of spatial correlations among contaminant concentrations in the simulation model did not significantly effect either the magnitude or the variance of the simulation risk estimates for sediment exposures.
Collapse
Affiliation(s)
- M R Adams
- Ebasco Environmental, Arlington, Virginia 22201
| | | | | | | |
Collapse
|