Prostatic tumor regrowth after initially successful castration therapy may be related to a decreased apoptotic cell death rate (original) (raw)
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The Prostate, 1993
The transplantable human prostate tumor lines PC-82 and PC-EW regress after androgen depletion. The castration-induced decline in tumor volume was faster in the PC-EW tumor (half-life 6 days) than in the PC-82 tumor (half-life 18 days), despite similar castrate androgen levels of less than 3 pmol/g tissue. Androgen ablation of the PC-82 tumor induced a wave of apoptosis, whereas in the PC-EW tumor, necrotic cell death was predominantly observed. The proliferative activity (BrdU index) of PC-82 and PC-EW tumor tissue declined from 3% to less than 1% after castration. After androgen depletion, some proliferative activity remained, the major part of which was localized in the (murine) stromal compartment of the tumors. In contrast to the PC-EW tumors, regrowth of androgen-ablated PC-82 tumors was rapidly induced by androgen resubstitution. The differences in response of these tumor models to androgen depletion and repletion appear to be related to the putative involvement of different cell death pathways. The role of the stroma in these processes is unclear. 0 1993 Wiley-Liss, Inc.
The Prostate, 1994
Male Copenhagen x Fisher F1 rats, transplanted with the androgen-sensitive Dunning R3327 PAP rat prostatic adenocarcinoma, were castrated when tumor volumes were approximally 1300 mm3. The rats were thereafter followed with measurements of tumor volume. Castration stopped tumor growth, but some of the tumors started to regrow after 7-36 weeks. These tumors relapsing from castration treatment were now considered to be androgen-insensitive. In this study, we defined relapse as the time when the tumor volume had increased to 200% of the volume at the time for castration. At this time, the rats were treated either with estradiol-17P (E2, 50 Fg S.C. daily) or vehicle for 8 weeks. After this period, tumor morphology was examined. The tumors in the vehicle-treated group were heterogeneous, and both highly and more dedifferentiated parts were present. The tumor growth rate was correlated to the epithelial cell nuclear size and its variance, and to the mitotic index. In the E2-treated group, tumor growth rate was retarded throughout the treatment period, and dedifferentiated tumor areas were rare. Estrogen treatment resulted in a reduction of nuclear area and mitotic index, a changed nuclear shape, and an increased apoptotic index compared to that in vehicletreated tumors. By castration, it is possible to induce an alteration of the androgen-sensitive Dunning R3327 PAP tumor phenotype to an androgen-insensitive tumor with an altered morphology. Estradiol-17P apparently inhibits not only the growth, but also postpones the castrationinduced dedifferentiation of the tumor.
Turkish Journal of Pathology
Objective: Deviations in the apoptotic process have been demonstrated in prostate carcinogenesis. We aimed to evaluate especially the process of extrinsic apoptosis in the spectrum of neoplastic lesions of the prostate epithelium so as to reveal the variations in the apoptotic process. Material and Method: The study included 20 benign prostatic hyperplasia, 8 high-grade prostatic intraepithelial neoplasia and 82 prostatic carcinoma patients. Immunohistochemistry was performed on sections obtained from materials of suprapubic prostatectomy, tru-cut biopsy, transurethral resection and radical prostatectomy. While Fas and FasL were evaluated in glandular and stromal areas, Dcr1 and FLIP were evaluated in only glandular areas. Intensity and extent of immunostaining for Fas and FasL antibodies were separately scored and both scores were summarized. The total score of ≥ 4 both for Fas and FasL, expressions of FLIP and Dcr1determined in more than 5% of glandular areas were accepted as positive. Results: Glandular FasL positivity was observed in 63.8 and 20% of the cases with prostatic carcinoma and benign prostatic hyperplasia, respectively (p=0.001). The loss of stromal Fas expression in PCa was obvious (p<0.001). FLIP positivity was more frequently seen in high-grade prostatic intraepithelial neoplasia and PCa. Conclusion: In prostatic carcinoma, decreased stromal Fas expression, contrary to higher glandular FasL positivity, supports the assertion that sensitivity of epithelial and stromal cells to apoptosis and their protective pathways against apoptosis undergo alterations. Increased FLIP expressions in high-grade prostatic intraepithelial neoplasia and prostatic carcinoma can also be interpreted accordingly.
The Prostate, 2007
BACKGROUND. Castration-induced involution of the normal prostate is caused by primary effects in the prostate stroma and vasculature, but if this is the case also in tumors is unknown. METHODS. Androgen-independent AT-1 prostate tumor cells were therefore injected into the ventral prostate (VP) in Copenhagen rats. Seven days later when the growing tumor was surrounded by normal VP tissue the rats were castrated and the effect examined 3 and 7 days later. RESULTS. Castration reduced vascular density in the surrounding VP tissue and this was accompanied by tumor cell hypoxia, apoptosis, and temporarily retarded tumor growth. Castration-induced VP tissue regression occurred more rapidly in the contra-lateral than in the tumor-bearing lobe. CONCLUSIONS. Androgen-independent tumor cell respond to castration when growing in an androgen-dependent environment. The presence of a tumor influences the castration response in the surrounding normal tissue. The microenvironment determines how prostate epithelial cells respond to castration.
The Prostate, 2017
Estrogens acting through the receptors ERα and ERβ participate in prostate normal growth and cancer. ERβ is highly expressed in the prostate epithelium, playing pro-apoptotic, anti-proliferative, and pro-differentiation roles. Apoptosis is activated by the intrinsic pathway after castration and by the extrinsic pathway after ERβ agonist treatment. This differential activation of apoptotic pathways is important since a major problem in the treatment of prostate cancer is the recurrence of tumors after androgen withdrawal. However, a comprehensive study about the pattern of apoptosis in the aging prostate is lacking, a knowledge gap that we aimed to address herein. Cellular age-related proliferative and apoptotic profiles of prostate tissue obtained from aging Wistar rats were evaluated. Cell death (caspase-3, -8, -9, TNFα) was assessed by immunohistochemistry, immunofluorescence, and TUNEL. Cell proliferation (MCM7) and cell survival factors (ERK1/2, p-ERK1/2, p-Akt, and NF-κB) were ...
advanced prostatic intraepithelial neoplasia (PIN) (1,2). These abnormalities are associated with a loss, decrease or altered these proteins is critical for normal morphogenesis. The aim of this study was to establish three-dimensional (3-D) in vitro Invasive prostatic carcinomas and prostatic intraepithelial cell models, derived from non-tumorigenic and tumorigenic neoplasia (PIN) are characterized by a loss of normal cell human prostatic epithelial cells, which could be used to organization, cell polarity, and cell:cell and cell:basement investigate mechanisms involved in acinar morphogenesis membrane adhesion. The objective of this study was to and differentiation in both normal and malignant prostatic establish in vitro three-dimensional (3-D) cell models which can be used to investigate mechanisms involved in acinar epithelium.
Malignant Transformation in a Nontumorigenic Human Prostatic Epithelial Cell Line1
Cancer Research, 2001
The human prostatic epithelial cell line BPH-1 is normally nontumorigenic in nude mice. The present report demonstrates that this cell line can be permanently transformed by its microenvironment to become tumorigenic. The establishment of a series of tumorigenic sublines based on this parental cell line is described. BPH-1 cells were induced to form tumors either by recombination with human prostatic carcinoma-associated fibroblasts (CAFs) or by exposure to carcinogenic doses of testosterone and estradiol (T؉E2) after recombination with rat urogenital sinus mesenchyme. Epithelial cells isolated from these tumors were established as cell strains in culture. When regrafted to nude mouse hosts epithelial cells isolated from CAF-or T؉E2-induced tumors were found to be consistently tumorigenic even in the absence of CAF or T؉E2. The T؉E2induced cell strains have been designated BPH1 TETD-A and-B and the CAF-induced strains are designated BPH1 CAFTD-01 through-08. In vitro, the cells had an epithelial morphology with a less well-defined cobblestone pattern than the parental line. They express SV40 large T antigen, confirming their derivation from the parental BPH-1 line. The BPH1 CAFTD strains formed colonies in soft agar, whereas the parental BPH-1 cells and the BPH1 TETD sublines did not. There was no immunocytochemically detectable expression of androgen (AR), ␣-estrogen (ER␣), or progesterone (PR) receptors by the parental BPH-1 cell line or by any of the tumor-derived cell strains. The cells uniformly coexpressed both basal and luminal cell-type cytokeratins and the basal cell marker p63. When grafted beneath the renal capsule of athymic mouse hosts, all of the tumor-derived cell strains consistently formed tumors. These were predominantly poorly or moderately differentiated squamous or adenosquamous tumors, similar in organization to the primary tumors from which the cell strains were derived. The cell strains continued to express both basal-and luminal-type cytokeratins in vivo. Some of the cell strains also coexpressed vimentin. E-cadherin expression was absent from many of the cells, although patches of cells expressing this marker were seen. The cells continued to express SV40T antigen. These cell strains, which are all derived from a common nontumorigenic progenitor, represent a useful resource for examining genetic and phenotypic changes during carcinogenesis.
Virchows Archiv, 2000
The cell kinetic of prostatic intraepithelial neoplasia (PIN) is poorly understood. Herein we report the kinetic pattern of PIN, both not associated (primary) and associated (secondary) with coexistent invasive carcinoma (PCa). Surgical specimens collected in 20 cases of primary PIN, 20 of secondary PIN and 20 of PCa were studied by MIB-1 immunostaining, in situ end- labeling (ISEL) and DNA histogram analysis, and the cell density in each case was estimated using the formula N=(nπ/4)2. Fifty high-power fields (HPF), or the complete lesion if smaller, were screened in each lesion, and both mean and standard deviation were recorded. Statistical differences were studied by means of Fisher’s exact test. ISEL indices were significantly (PPCa (0.1±0.3) than in primary PIN (0.5±0.3), while the MIB-I indices were similar in both conditions (P=0.56). Statistically significant differences were also detected for both MIB-1 and ISEL indices when secondary PIN (MIB-1 1.9±0.7, ISEL 3.7±3.3) was compared with primary PIN (MIB-1 2.5±2.1, ISEL 0.5±0.3) and PCa (PPPCa (39.0±8.8) and secondary PIN (32.9±14.3). In conclusion, early prostatic tumor is mainly defined by down-regulated apoptosis rather than by increased proliferation. Secondary PIN displays unique kinetic features suggesting an evolved stage of primary PIN.
Apoptosis in the transplanted caninetransmissible venereal tumor during growth and regression phases
Twelve male, mongrel, adult dogs were subcutaneously transplanted with cells originated from two canine transmissible venereal tumors (TVT). The aim was to demonstrate and to quantify the occurrence of apoptosis in the TVT regression. After six months of transplantation, a tumor sample was obtained from each dog, being six dogs with TVT in the growing phase and six in the regression phase as verified by daily measurements. Samples were processed for histological and ultrastructural purposes as well as for DNA extraction. Sections of 4µm were stained by HE, Shorr, methyl green pyronine, Van Gieson, TUNEL reaction and immunostained for P53. The Shorr stained sections went through morphometry that demonstrated an increase of the apoptotic cells per field in the regressive tumors. It was also confirmed by transmission electron microscopy, which showed cells with typical morphology of apoptosis and by the TUNEL reaction that detected in situ the 3'OH nick end labeling mainly in the regressive tumors. The regressive TVTs also showed an intensified immunostaining for P53 besides a more intense genomic DNA fragmentation detected by the agarose gel electrophoresis. In conclusion, apoptosis has an important role in the regression of the experimental TVT in a way that is P53-dependent.