Cell proliferation and apoptosis in prostate tumors and adjacent non-malignant prostate tissue in patients at different time-points after castration treatment.
BACKGROUND
Androgen ablation is the standard treatment for advanced prostate cancer but the short-term cellular effects are largely unknown.


METHODS
Sextant prostate biopsies were taken from 77 prostate cancer patients before and 1-10 days after castration treatment. Apoptosis, cell proliferation, and morphology were studied in malignant and non-malignant tissue, using stereological and immunohistochemical methods.


RESULTS
Epithelial cell proliferation was significantly decreased both in non-malignant and malignant epithelium already 1 day after therapy. It remained low until day 7, but increased thereafter in the remaining non-malignant epithelial cells and in some tumors. Epithelial cell apoptosis was significantly increased during the first week and then returned to basal levels. The maximal apoptotic indexes, seven- and two-times the intact levels in the non-malignant and malignant glands, respectively, were found at days 3-4 or even earlier in the tumors. Signs of tumor shrinkage such as glandular collapse and decreased tumor cell size were observed from day 3 in most tumors.


CONCLUSIONS
The present study shows that the magnitude and kinetics of the response to castration in the normal human prostate is very similar to the response previously described in rodents. We also demonstrate that most human prostate tumors rapidly respond to castration indicating the need for further evaluation of when and how to best monitor the effects of hormone ablation therapy in prostate cancer patients.
Ohlson
Nina
N
Department of Medical Biosciences, Pathology, and Surgical and Perioperative Sciences, Umeå University, Umeå, Sweden.
Wikström
Pernilla
P
Stattin
Pär
P
Bergh
Anders
A
D000368:Aged; D000369:Aged, 80 and over; D000726:Androgen Antagonists / Q000627:therapeutic use; D017209:Apoptosis; D001706:Biopsy; D002369:Castration; D049109:Cell Proliferation; D006801:Humans; D007700:Kinetics; D008297:Male; D008875:Middle Aged; D011467:Prostate / Q000166:cytology* / Q000187:drug effects; D011471:Prostatic Neoplasms / Q000188:drug therapy* / Q000503:physiopathology*
D000726:Androgen Antagonists