Paul Andrew Johnston

B.Sc., Ph.D.

Paul A. Johnston is a professor in the department of Pharmaceutical Sciences, School of Pharmacy at the University of Pittsburgh. He obtained a B.Sc. with Honors (2.1) (1978) and a Ph.D. (1983) in Biochemistry, from the University of East Anglia in Norwich, England. Subsequent postdoctoral positions in the department of Pharmacology at the University of North Carolina, the Pathology department of Duke University, and at the Howard Hughes Institute of the University of Texas Southwestern have provided a diversity of experience in biochemistry, molecular biology, cell biology, immunology, protein purification and recombinant protein expression. Dr Johnston has thirty years of drug discovery experience in the Pharmaceutical (American Cyanamid, Sphinx Pharmaceuticals & Eli Lilly), Biotechnology (Embrex) and academic sectors (University of Pittsburgh). Throughout his career Dr. Johnston has been an innovator of cell based approaches to lead generation and optimization and pioneered the development and implementation of high content imaging technology to drug discovery. A founding member of the Society for Biomolecular Imaging and Informatics (SBI2) in 2012, he is a past president and former sponsorship/exhibitor contact for the annual SBI2 conference and exhibit show. In the summer of 2005, he returned to academia to design and build the University of Pittsburgh Molecular Library Screening Center (PMLSC) where he led 21 HTS campaigns and reconfigured the NCI 60 cell line assays for cancer drug combination screening. In 2011, Dr. Johnston joined the Department of Pharmaceutical Sciences in the School of Pharmacy where he established his own chemical biology laboratories and his research has focused on the application of novel drug discovery strategies to identify new and effective drugs or drug combinations for prostate cancer, melanoma, head and neck cancer, and hepatocellular carcinoma. He also provides expertise in HTS/HCS assay development and implementation for drug discovery collaborations in other therapeutic areas. Dr. Johnston teaches biochemistry and drug discovery courses to students in the Pharm.D. and Ph.D. programs of the School of Pharmacy.

Graduate Program Affiliation(s)
Biochemical pharmacology,Medicinal chemistry
Recent Publications

Last 5 Years:
1. Close DA, Wang AX, Kochanek SJ, Shun T, Eiseman JL, Johnston PA. Implementation of the NCI-60 Human Tumor Cell Line Panel to Screen 2260 Cancer Drug Combinations to Generate >3 Million Data Points Used to Populate a Large Matrix of Anti-Neoplastic Agent Combinations (ALMANAC) Database. SLAS Discov. 2019 Mar;24(3):242-263. doi: 10.1177/2472555218812429. Epub 2018 Nov 30. PMID: 30500310
2. Kochanek SJ, Close DA, Johnston PA. High Content Screening Characterization of Head and Neck Squamous Cell Carcinoma Multicellular Tumor Spheroid Cultures Generated in 384-Well Ultra-Low Attachment Plates to Screen for Better Cancer Drug Leads. Assay Drug Dev Technol. 2019 Jan;17(1):17-36. doi: 10.1089/adt.2018.896. Epub 2018 Dec 28. PMID: 30592624
3. Kochanek SJ, Close DA, Wang AX, Shun T, Empey PE, Eiseman JL, Johnston PA. Confirmation of Selected Synergistic Cancer Drug Combinations Identified in an HTS Campaign and Exploration of Drug Efflux Transporter Contributions to the Mode of Synergy. SLAS Discov. 2019 Jul;24(6):653-668. doi: 10.1177/2472555219844566. PMID: 31039321
4. Fancher AT, Hua Y, Strock CJ, Johnston PA. Assays to Interrogate the Ability of Compounds to Inhibit the AF-2 or AF-1 Transactivation Domains of the Androgen Receptor. Assay Drug Dev Technol. 2019 Nov/Dec;17(8):364-386. doi: 10.1089/adt.2019.940. Epub 2019 Sep 6. PMID: 31502857
5. Dorman HR, David Close, Wingert BM, Camacho CJ, Johnston PA, Smithgall TE. Discovery of Non-peptide Small Molecule Allosteric Modulators of the Src-family Kinase, Hck. Front Chem. 2019 Nov 28; 7:822. doi: 10.3389/fchem.2019.00822. eCollection 2019. PMID: 31850311
6. Kochanek SJ, Close DA, Camarco DP, Johnston PA. Maximizing the Value of Cancer Drug Screening in Multicellular Tumor Spheroid Cultures: A Case Study in Five Head and Neck Squamous Cell Carcinoma Cell Lines. SLAS Discov. 2020 Apr; 25(4):329-349. doi: 10.1177/2472555219896999. Epub 2020 Jan 25. PubMed PMID: 31983262; PubMed Central PMCID: PMC7343231.
7. Loong HH, Wong AM, Chan DT, Cheung MS, Chow C, Ding X, Chan AK, Johnston PA, Lau JY, Poon WS, Wong N. Patient-derived tumor organoid predicts drugs response in glioblastoma: A step forward in personalized cancer therapy? J Clin Neurosci. 2020 Aug; 78:400-402. doi: 10.1016/j.jocn.2020.04.107. Epub 2020 Apr 24. Review. PubMed PMID: 32340843.
8. Aggarwal V, Miranda O, Johnston PA, Sant S. Three dimensional engineered models to study hypoxia biology in breast cancer. Cancer Lett. 2020 Oct 10; 490:124-142. doi: 10.1016/j.canlet.2020.05.030. Epub 2020 Jun 20. Review. PubMed PMID: 32569616; PubMed Central PMCID: PMC7442747. (Peer reviewed review article).
9. Judson R, Houck K, Paul Friedman K, Brown J, Browne P, Johnston PA, Close DA, Mansouri K, Kleinstreuer N. Selecting a minimal set of androgen receptor assays for screening chemicals. Regul Toxicol Pharmacol. 2020 Nov; 117:104764. doi: 10.1016/j.yrtph.2020.104764. Epub 2020 Aug 14. PubMed PMID: 32798611.
10. Close DA, Kirkwood JM, Fecek RJ, Storkus WJ, Johnston PA. Unbiased High-Throughput Drug Combination Pilot Screening Identifies Synergistic Drug Combinations Effective against Patient-Derived and Drug-Resistant Melanoma Cell Lines. SLAS Discov. 2021 Jun;26(5):712-729. doi: 10.1177/2472555220970917. Epub 2020 Nov 18. PubMed PMID: 33208016; PubMed Central PMCID: PMC8128935.
11. Close DA, and Johnston PA. Detection and impact of hypoxic regions in multicellular tumor spheroid cultures formed by head and neck squamous cell carcinoma cells lines. SLAS Discov. 2022 Jan;27(1):39-54. doi: 10.1016/j.slasd.2021.10.008. Epub 2021 Oct 13. PMID: 35058175
12. Long K, Vaughn Z, McDaniels MD, Joyasawal S, Przepiorski A, Parasky E, Sander V, Close D, Johnston PA, Davidson AJ, de Caestecker M, Hukriede NA, Huryn DM. Validation of HDAC8 Inhibitors as Drug Discovery Starting Points to Treat Acute Kidney Injury. ACS Pharmacol Transl Sci. 2022 Mar 16;5(4):207-215. doi: 10.1021/acsptsci.1c00243. eCollection 2022 Apr 8. PMID: 35434532

Presentations in last 5 years from a total of 73:
1. Paul A. Johnston. “Development and Characterization of Patient Derived 3D Hepatocellular Carcinoma Organoid Models using HCS Methods and their Application to Precision Medicine and Drug Discovery.” (4-FEB-2019) Presented at the 6th annual conference of the Society for Laboratory Automation and Screening (SLAS) in Washington D.C., February 2019. Track name: Automation and High Throughput Technologies. Session title: Advancing imaging technologies to bridge the gap between high content and high throughput.
2. Paul A. Johnston. “Targeting Androgen Receptor Interactions with Transcription Intermediary Factor 2 to find Castration Resistant Prostate Cancer Drug Leads.” (21-FEB-2019) Molecular Biophysics/Structural Biology Departmental Seminar, 6014 Biomedical Science Tower 3, University of Pittsburgh.
3. Paul A. Johnston, Maximizing the Value of Cancer Drug Screening in Multicellular Tumor Spheroid Cultures - Are you Analyzing your 3D Tumor Models Appropriately? (19-SEPT-2019) Society of Biomolecular Imaging and Informatics (SBI2) 6th Annual Conference at Joseph B. Martin Conference Center, Harvard Medical School, Boston, MA. Session III. "Therapeutic Drug Discovery for Complex Disease."
4. Paul A. Johnston. Drug Combination High Throughput Screening: An unbiased data driven strategy to identify synergistic cancer therapies! (4-DEC-2019). Department of Pharmacology and Chemical Biology Seminar Series, Emory University School of Medicine, 1510 Clifton Road, Suite 5001, Atlanta, GA.
5. Paul A. Johnston. Maximizing the Value of Cancer Drug Screening in Multicellular Tumor Spheroid Cultures - Are you Analyzing your 3D Tumor Models Appropriately? (12-DEC-2019) University of Pittsburgh Aging Institute Research Seminar Series. 100 Technology Drive, 5th Floor; Pittsburgh, PA.
6. Paul A. Johnston.. Maximizing the Value of Cancer Drug Screening in Multicellular Tumor Spheroid Cultures - Are you Analyzing your 3D Tumor Models Appropriately? (28-JAN-2020) Presented at the 9th annual conference of the Society for Laboratory Automation and Screening (SLAS) in San Diego, CA. Presentation Date: January 28th, 2020. Track name: Assay Development and Screening. Session title: Advanced In Vitro Cell Culture Systems.
7.. Paul A. Johnston.. Maximizing the Value of Cancer Drug Screening in Multicellular Tumor Spheroid Cultures - Are you Analyzing your 3D Tumor Models Appropriately? (27-FEB-2020) Duquesne University Graduate School of Pharmaceutical Sciences Seminar Series – External Speaker, invited by David J. Lapinsky, Ph.D. Associate Professor of Medicinal Chemistry, Division of Pharmaceutical, Administrative, and Social Sciences Duquesne University School of Pharmacy.
8. Paul A. Johnston. “Drug Combination HTS – an unbiased data driven strategy to identify synergistic cancer therapies!” (19-NOV-2020) Invited speaker Dept. of Pharmaceuticals Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of Colorado Anschutz Medical Campus, Aurora CO, Thursday November 19th, 2020. Invited by Dr. Daniel LaBarbera, Associate Professor of Drug Discovery and Medicinal Chemistry, Director High-throughput Drug Discovery and Chemical Biology Core Facility, Co-Director Drug Discovery and Development Shared Resource CU AMC Cancer Center, and the Seminar Committee Jed Lampe, Rebecca McCullough & Rochelle Cassell. Online Zoom presentation.
9. Paul A. Johnston. Maximizing the Value of Cancer Drug Screening in Multicellular Tumor Spheroid Cultures - Are you Analyzing your 3D Tumor Models Appropriately? (3-DEC-2020) Invited speaker Cancer Physiology and Drug Discovery Group of the Moffat Cancer Center, Tampa FL, Thursday December 3, 2020. Invited by Dr. Derek Duckett, Senior Member & Chair, Drug Discovery and Dr. Patsy McDonald, Associate Member, Cancer Physiology. Online Zoom presentation.
10. Paul A. Johnston. Quantitative High Throughput Screening (qHTS) of Patient Derived Hepatocellular Carcinoma Models to Identify Novel Probes or Drug Leads for Development into Therapeutic Agents. (1-Jun-2021) Invited speaker at the University of Pittsburgh Liver Research Center virtual seminar series, Tuesday June 1st, 2021.
11. Paul A. Johnston, Implementing 3D Models for Cancer Drug Discovery. Presented in the High Throughput Advanced Cellular Models session at the Society for Laboratory Automation and Screening (SLAS) Building Biology in 3D Symposium, October 26th to 27th 2021, La Jolla, CA.
12. Paul A. Johnston, Maximizing the value of your 3D Multicellular Tumor Models for Cancer Drug Discovery. Presented in the 3D and iPS Cell Models for Drug Discovery at the CHI World Preclinical Congress, June 23-24th, 2022, Boston, MA. (postponed).