Noninvasive measurement of androgen receptor signaling with a positron-emitting radiopharmaceutical that targets prostate-specific membrane antigen Journal Article


Authors: Evans, M. J.; Smith-Jones, P. M.; Wongvipat, J.; Navarro, V.; Kim, S.; Bander, N. H.; Larson, S. M.; Sawyers, C. L.
Article Title: Noninvasive measurement of androgen receptor signaling with a positron-emitting radiopharmaceutical that targets prostate-specific membrane antigen
Abstract: Despite encouraging clinical results with next generation drugs (MDV3100 and abiraterone) that inhibit androgen receptor (AR) signaling in patients with castration-resistant prostate cancer (CRPC), responses are variable and short-lived. There is an urgent need to understand the basis of resistance to optimize their future use. We reasoned that a radiopharmaceutical that measures intra-tumoral changes in AR signaling could substantially improve our understanding of AR pathway directed therapies. Expanding on previous observations, we first show that prostate-specific membrane antigen (PSMA) is repressed by androgen treatment in multiple models of AR-positive prostate cancer in an AR-dependent manner. Conversely, antiandrogens up-regulate PSMA expression. These expression changes, including increased PSMA expression in response to treatment with the antiandrogen MDV3100, can be quantitatively measured in vivo in human prostate cancer xenograft models through PET imaging with a fully humanized, radiolabeled antibody to PSMA, 64Cu-J591. Collectively, these results establish that relative changes in PSMA expression levels can be quantitatively measured using a human-ready imaging reagent and could serve as a biomarker of AR signaling to noninvasively evaluate AR activity in patients with CRPC.
Keywords: controlled study; protein expression; unclassified drug; nonhuman; positron emission tomography; prostate specific antigen; animal cell; mouse; animal tissue; animal experiment; animal model; in vivo study; cancer cell culture; tumor xenograft; prostate cancer; quantitative analysis; radiopharmaceutical agent; androgen receptor; upregulation; androgen deprivation therapy; non invasive procedure; cell strain lncap; 4 [3 [4 cyano 3 (trifluoromethyl)phenyl] 5,5 dimethyl 4 oxo 2 thioxo 1 imidazolidinyl] 2 fluoro n methylbenzamide; j 591 cu 64
Journal Title: Proceedings of the National Academy of Sciences of the United States of America
Volume: 108
Issue: 23
ISSN: 0027-8424
Publisher: National Academy of Sciences  
Date Published: 2011-06-07
Start Page: 9578
End Page: 9582
Language: English
DOI: 10.1073/pnas.1106383108
PROVIDER: scopus
PMCID: PMC3111331
PUBMED: 21606347
DOI/URL:
Notes: --- - "Export Date: 17 August 2011" - "CODEN: PNASA" - "Source: Scopus"
Altmetric
Citation Impact
BMJ Impact Analytics
MSK Authors
  1. Charles L Sawyers
    226 Sawyers
  2. Neil Harrison Bander
    62 Bander
  3. Michael John Evans
    22 Evans
  4. Steven M Larson
    959 Larson