Intermittent androgen suppression in the LuCaP 23.12 prostate cancer xenograft model

Prostate. 2000 Apr 1;43(1):63-70. doi: 10.1002/(sici)1097-0045(20000401)43:1<63::aid-pros9>;2-d.


Background: Intermittent androgen suppression (IAS) has been proposed as a method of delaying the onset of androgen-independent growth in prostate cancer. While several pilot studies have demonstrated the feasibility of such a treatment, no study to date has defined the effect of IAS on survival.

Methods: We developed an IAS protocol for mice bearing the LuCaP 23.12 human prostate cancer xenograft, with each cycle consisting of 1 week of androgen replacement with a testosterone pellet followed by 3 weeks of androgen withdrawal. Mice that responded to castration with a 40% or greater decrease in serum prostate-specific antigen (PSA) were randomized to treatment with either continuous androgen suppression (CAS) or IAS. Serum PSA, tumor volume, and overall survival were monitored.

Results: A total of 75 mice met the randomization criteria. There was no significant difference of survival between animals treated with CAS or IAS (185 vs. 239 days, P = 0.1835). Serum PSA showed evidence of cycling with hormonal manipulation. No cycling was noted in tumor volume.

Conclusions: IAS is not associated with a decrease in survival compared to CAS, yet in patients may offer quality-of-life improvements. Further studies of IAS in the setting of Institutional Review Board (IRB) approved clinical trials should be encouraged. Prostate 43:63-70, 2000. Published 2000 Wiley-Liss, Inc.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Drug Administration Schedule
  • Humans
  • Male
  • Mice
  • Mice, Inbred BALB C
  • Neoplasm Transplantation
  • Prostate-Specific Antigen / blood
  • Prostatic Neoplasms / blood
  • Prostatic Neoplasms / drug therapy*
  • Prostatic Neoplasms / mortality
  • Prostatic Neoplasms / pathology
  • Random Allocation
  • Testosterone / administration & dosage*
  • Testosterone / therapeutic use
  • Transplantation, Heterologous


  • Testosterone
  • Prostate-Specific Antigen