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S A Shain

Publications and source records attributed to S A Shain.

At least 37 records · Page 2Linked to original sources
PubMed1987

Proliferation of AXC/SSh rat prostate cancer cells in vitro is androgen modulated.

We used heterogeneous parental cultures of AXC/SSh rat prostate cancer cells to isolate clonally derived prostate cancer cell lines. Light and electron microscopic analyses established that parental and clonally isolated cells possess features characteristic of secretory epithelium. Biochemical analyses showed that these cells contained androgen receptors and acid phosphatase and 5 alpha-reductase activity; phenotypic markers characteristic of differentiated prostate epithelium. Content of these prostate epithelial cell markers was variable and cell line specific. We used selected cell lines to examine androgen modulation of AXC/SSh rat prostate cancer cell proliferation in vitro. We found that proliferation of C-family or D-family cells, those respectively maintained on medium without additions or medium containing 10(-7) M 5 alpha-dihydrotestosterone, was not affected by changes in medium testosterone concentration through the range 10(-6)-10(-9) M. In contrast, testosterone modified proliferation of T-family cells, those maintained on medium containing 10(-7) M testosterone, and effects were antagonized by the anti-androgen RU 23908. Preliminary studies established that AXC/SSh rat prostate cancer cells elaborate polypeptide components which stimulate in vitro cell proliferation. Both the ability to elaborate these components and their effects on in vitro cell proliferation appeared to be cell line specific.

Animals↗
PubMed1986

Immunocytochemical assay of estrogen receptors in endometrial carcinoma with monoclonal antibodies. Comparison with biochemical assay.

Specimens of endometrial adenocarcinoma, surgically obtained from 18 women, were analyzed for distribution of estrogen receptors by an immunocytochemical assay, employing monoclonal anti-estrophilin antibodies and the peroxidase-antiperoxidase technique. Results were compared with biochemical receptor analyses, and were in concordance in 83% of them. Marked tumor cell and tissue receptor heterogeneity were apparent with the immunocytochemical method, and a variety of patterns of nuclear staining in positive tissue samples were revealed. These results indicate that the immunohistologic method will provide a number of entirely new variables that may eventually be correlated with both clinical and pathologic features of this malignancy, and may prove to be of value in the prediction of clinical endocrine response.

Adenocarcinoma↗
PubMed1986

Aging in the AXC/SSh rat: characterization of moderately abundant ventral prostate proteins showing age-dependent diminution and one protein exhibiting age-invariant content.

To determine whether prior demonstrations of age-related decrements in prostate content of minor, androgen regulated proteins represent a generalized phenomenon, we validated a denaturing polyacrylamide gel electrophoretic protocol for separation and quantification of moderately abundant ventral prostate cytoplasmic proteins. We established age-related, progressive 3- to 3.5-fold decreases in prostate content of proteins of 90, 79, 63, and 58 kDa and found that content of a 46 kDa protein was age-invariant. The amount of 90 and 46 kDa proteins was not significantly altered, whereas the level of 79, 63 and 58 kDa proteins decreased during 72 h post-orchiectomy of 3-month-old rats. Testosterone injection of intact 26-month-old rats caused an average 2-fold increase in 90, 79, 63, and 58 kDa protein content and did not affect 46 kDa protein level. Because we demonstrated the 46 kDa protein is not a secretory protein, absence of an affect of aging or testosterone on prostate content is not due to secretion mediated inaccessibility to intracellular processing. The apparent relation between age and prostate content of these proteins is not a consequence of potential age-related changes in ventral prostate cell content or distribution because biochemical and histologic analyses show this does not significantly occur. Our studies establish age-related decreases in ventral prostate content of moderately abundant, androgen responsive proteins and show that content of at least one protein is age- and androgen-independent. It remains to be determined whether these findings reflect direct effects of gene regulation.

Aging↗
PubMed1986

The aging AXC/SSh rat: assessment of longevity and prevalence of neoplastic and nonneoplastic diseases in necropsied rats.

Median life span, 906 days, was identical for conventionally reared, ad libitum fed AXC/SSh male and female rats and exceeded that of most other conventionally or barrier maintained rats. AXC/SSh rat longevity partially reflects the 25% incidence of moderate to severe nephropathy occurring at 30 to 41 months. Because male survival was related to sibship, p less than .02, and female survival was not, p greater than .05, a genetic component may affect male longevity. Maximum body weight was achieved during the initial 20% of life span and maintained through the final 10% when mean loss was 14 and 15%, respectively, for males and females. Pituitary adenomas occurred in 65% of females and 10% of males. Mammary adenocarcinoma occurred in 26% of females. Interstitial cell tumors were not detected in males younger than 24 months. Prostate adenocarcinomas occurred in 23% of males older than 29 months. The longevity of AXC/SSh rats and their low incidence of nephropathy suggests they are an attractive model for studies in aging.

Aging↗
PubMed1986

Sexual dimorphism characterizes steroid hormone modulation of rat aortic steroid hormone receptors.

Quantification of aortic androgen and estrogen receptor content and distribution in AXC/SSh rats established that the total androgen receptor content in intact young mature males (mean +/- SD, 55 +/- 13 fmol/mg DNA) was indistinguishable (P greater than 0.05) from that in proestrous females (50 +/- 3 fmol/mg DNA). However, 60% of male aortic androgen receptors were in the nuclear fraction, whereas all proestrous female aortic androgen receptors were in the cytoplasmic fraction. The total aortic estrogen receptor content of intact young mature males (70 +/- 16 fmol/mg DNA) was indistinguishable (P greater than 0.05) from that of proestrous (92 +/- 12) or diestrous (77 +/- 4) females. However, 50% of proestrous female aortic estrogen receptors were in the nuclear fraction, whereas male or diestrous female aortic estrogen receptors were restricted to the cytoplasmic fraction. To assess estrogen receptor function, we characterized aortic cytoplasmic progesterone receptors and established that the receptor content of intact male aortae (101 +/- 3 fmol/mg DNA) was not significantly different (P greater than 0.05) from that of diestrous female aortae (100 +/- 11). 17 beta-Estradiol injection of intact males failed to affect aortic progesterone receptor content (93 +/- 17 fmol/mg DNA). However, injection of orchiectomized males with 17 beta-estradiol significantly (P less than 0.05) increased progesterone receptor content to 208 +/- 24 fmol/mg DNA. This value is twice that of intact males and is not significantly different (P greater than 0.05) from the aortic cytoplasmic progesterone receptor content (190 +/- 32 fmol/mg DNA) of 17 beta-estradiol-injected oophorectomized females. These studies establish that intracellular distribution of aortic androgen and estrogen receptors of male or female AXC/SSh rats is regulated by endogenous hormones. The observation that 17 beta-estradiol modulates aortic progesterone receptor content indicates that rat aortic estrogen receptors are physiologically functional. Our data imply that steroid hormones directly regulate aspects of rat cardiovascular cell function and that sexually dimorphic differential regulation may characterize male and female aortic metabolism.

Animals↗
PubMed1986

Aging in the AXC/SSh rat: diminished prostate L-ornithine decarboxylase (ODC) activity reflects diminished prostate ODC protein and transcript content.

Immunotitration of L-ornithine decarboxylase (ODC) activity in ventral prostates of young mature (6-month-old) and aged (26-month-old) AXC/SSh rats established that the relation between enzyme activity and prostate ODC mass content was age invariant, demonstrating that the 4-fold diminution in prostate ODC activity in aged subjects represents decreased ODC protein content. Testosterone treatment of aged rats increased prostate ODC activity 2-fold and did not affect prostate ODC half-life. These latter findings and the preceding observation established that the testosterone-mediated increase in prostate ODC activity in aged individuals reflected increased ODC mass content. The half-life of prostate S-adenosyl-L-methionine decarboxylase, another prominent enzyme of polyamine biosynthesis, also was not altered by testosterone treatment of 26-month-old animals. The age-related diminution and testosterone-mediated increase in ventral prostate ODC activity occurred in concert with comparable quantitative changes in ventral prostate ODC transcript content. Because plasma testosterone content was age invariant between 3 and 18 months, the age span during which much of the reduction in prostate ODC activity occurs, and then declined by 50% at 26 months, our studies suggest that age-related diminutions in prostate ODC activity and transcript content reflect altered prostate sensitivity to androgen rather than response to diminished plasma testosterone content. Our data imply that age-related alterations in androgen regulation of androgen-responsive genes may be characteristic of the prostate during aging.

Adenosylmethionine Decarboxylase↗
PubMed1986

Differential androgen modulation of AXC/SSh rat prostate cancer cell proliferation in vitro and its antagonism by antiandrogen.

We examined androgen modulation of proliferation of clonally derived AXC/SSh rat prostate cancer cells. C-family cells were maintained on medium without addition of androgens. D-family cells were maintained on medium containing 10(-7) M 5 alpha-dihydrotestosterone and T-family cells were maintained on medium containing 10(-7) M testosterone. Proliferation of all AXC/SSh prostate cancer cell lines during propagation on media containing fetal bovine serum was not altered by changes in media testosterone concentration through the range 10(-6) to 10(-9) M. Similarly, proliferation of C- or D-family cell lines, during propagation on media containing steroid depleted, charcoal stripped fetal bovine serum, was not altered by changes in media testosterone concentration through the range 10(-6) to 10(-9) M. By contrast, proliferation of T-family cell lines during propagation on charcoal stripped fetal bovine serum was modulated by androgens; effects were androgen concentration dependent and maximum at 10(-8) to 10(-7) M. Androgens decreased T5 cell proliferation rate and diminished achievable saturation density, whereas T1 cell proliferation rate was increased by androgens. In contrast, T6 cell proliferation rate was unaffected by androgens; however, saturation density was increased. Effects were antagonized by the antiandrogen RU 23908, Anandron, establishing androgen specificity of testosterone or 5 alpha-dihydrotestosterone mediated changes in proliferation.

Androgen Antagonists↗
PubMed1984

Biochemical and morphological characterization of clonal AXC rat prostate cancer cells.

We used three heterogeneous parental cultures of LSC-AXC rat prostate cancer cells: LSC-AXC-C/O, cells maintained on culture medium; LSC-AXC-D/O, cells maintained on culture medium containing 10(-7) M 5 alpha-dihydrotestosterone; and LSC-AXC-T/O, cells maintained on culture medium containing 10(-7) M testosterone, to isolate clonally derived cell lines. Eleven of 15 clonal cell lines were tumorigenic when inoculated into intact male AXC rats. Eight tumorigenic clonal cell lines were selected for further evaluation, and all were found to possess features characteristic of secretory epithelium, as judged by light and electron microscopy. All parental cell lines and the eight selected clonal cell lines contained cytoplasmic and nuclear androgen receptors. Total receptor content was 131 +/- 61 (S.D.), 43 +/- 32, and 274 +/- 96 fmol/100 micrograms of DNA, respectively, for C-, D-, and T-cells. The differences were significant (p less than 0.05). Androgen receptor content of young mature or senescent AXC rat ventral prostate, respectively, is 518 +/- 58 and 266 +/- 40 fmol/100 micrograms of DNA. Since chromosomal analysis established that LSC-AXC prostate cancer cells are hypotriploid, androgen receptor content per cell in C- and T-cells is indicated to be either greater than or equal to that of senescent AXC rat ventral prostate, the tissue in which the original adenocarcinoma arose. Parental and clonal cell lines contained 5 alpha-reductase activity. There were significant differences (p less than 0.05) in both total reductase activity and metabolite distribution. Consequently, the intracellular content of testosterone metabolites was cell line specific. All characterized cell lines contained a higher concentration (p less than 0.05) of APase activity than did young mature or senescent AXC rat ventral prostate. In 6 of 11 cell lines, prostate-secretory APase concentration exceeded (p less than 0.05) that of AXC rat ventral prostate. However, the relative content of secretory APase compared to total APase in carcinoma cells consistently was less (p less than 0.05) than that of AXC rat ventral prostate. These studies document the establishment of clonal AXC rat prostate adenocarcinoma cell lines which have retained important morphological and phenotypic markers characteristic of differentiated prostate epithelium. Since these cells are tumorigenic and represent a spectrum of retained differentiated phenotypic markers, they should be particularly useful for in vivo and in vitro studies of hormonal regulation of prostate cancer cell behavior.

Acid Phosphatase↗
PubMed1983

Altered androgen regulation of differentiated ventral prostate function during aging of the AXC rat.

We have examined testosterone regulation of differentiated androgen responsive ventral prostate function in aging AXC rats as a possible means of identifying age-related changes in prostate gene function. Concerning cellular content of functional macromolecules, we identified three categories of age-related change in ventral prostate: (1) diminutions completely reversible by short-term chronic testosterone treatment, as exemplified by androgen receptor content; (2) diminutions partially reversible by testosterone treatment, as exemplified by prolactin receptor content and L-ornithine-decarboxylase (ODC) activity; and (3) diminutions not reversed by exogenous testosterone treatment, as exemplified by S-adenosyl-L-methionine decarboxylase (AMDC) activity. A fourth category of alteration revealed apparent age-related changes in polyamine homeostasis. The anabolic products of ODC and AMDC activities, putrescine, spermidine and spermine, showed an age-related diminished dependence between the activities of ODC and AMDC and ventral prostate polyamine content. The possibility that these changes reflect age-related alterations in ventral prostate gene activity is under investigation.

Adenosylmethionine Decarboxylase↗
PubMed1983

Aging in the AXC rat: diminished prostatic S-adenosyl-L-methionine decarboxylase (AMDC) activity appears to reflect altered expression of the AMDC gene.

We purified AXC rat hepatic S-adenosyl-L-methionine decarboxylase (AMDC) 4900-fold and obtained a preparation that was 75% AMDC. This material caused elaboration of rabbit antirat AMDC antibodies that essentially were monoprecipitating. Antibody from one rabbit was highly effective as an inactivator of prostatic AMDC activity and was used to evaluate the quantitative relationship between antigenic mass and AMDC activity in ventral and dorsolateral prostates of young mature (185-day-old) and aged (776-day-old) AXC rats. Although AMDC activity of aged AXC rat prostates was diminished (ventral, 68%; dorsolateral, 50%), the quantities of antibody required to inactivate 1 U AMDC activity in prostates of young mature and aged rats were identical. This antibody effectively recognized enzymatically inactive AMDC, which is antigenically similar to active AMDC. Therefore, the age-related reductions in prostatic AMDC activity are not due to the production of so-called altered AMDC. Four days of exogenous testosterone treatment of aged AXC rats failed to enhance ventral prostate AMDC activity, whereas AMDC activity in dorsolateral prostates was elevated 2.3-fold. New AMDC activity was antigenically identical to that in dorsolateral prostates of untreated young mature or aged AXC rats. Because we previously established that age-related reductions in AXC rat prostatic AMDC activity are due to neither trivial causes nor enhanced inactivation, our present studies imply that reductions in AMDC activity are due to decreased prostatic AMDC content. These studies are an initial demonstration of senescence-related quantitative reductions in the prostatic content of AMDC molecules, which appear to represent altered expression of a specific androgen-responsive prostatic gene.

Adenosylmethionine Decarboxylase↗
PubMed1983

Creatine kinase and lactate dehydrogenase: stability of isoenzymes and their activity in stored human plasma and prostatic tissue extracts and effect of sample dilution.

We examined the effect of storing human plasma or extracts of prostate at -90 degrees C on the activity of creatine kinase and lactate dehydrogenase and isoenzyme distribution. Enzyme activities were unaltered during storage for as long as six weeks. If these preparations were thawed only once at 2 to 4 degrees C, they could be stored for as long as 165 days at -90 degrees C with no change in isoenzyme distribution. Inexplicably, apparent isoenzyme distribution of prostatic lactate dehydrogenase was sensitive to sample dilution, whereas the isoenzyme distribution of lactate dehydrogenase in plasma was not. Our observations emphasize the importance of validating details of analytical protocols that are to be used for quantification of new types of specimens.

Creatine Kinase↗
PubMed1983

Inability of cytoplasmic or nuclear androgen receptor content or distribution to distinguish benign from carcinomatous human prostate.

We used exchange saturation analysis at 15 degrees to quantitate total cytoplasmic and nuclear androgen receptor content of 70 patient specimens. Cytoplasmic androgen receptor contents (fmol/mg DNA) for eight specimens of clinically benign hyperplasia, 14 specimens of histologically hyperplastic prostate obtained at cystoprostatectomy, and carcinomatous and noncarcinomatous prostate obtained at radical prostatectomy for prostatic carcinoma, 48 specimens, respectively, were 830 +/- 165 (mean +/- S.E.), 890 +/- 445, 955 +/- 240, and 750 +/- 95. Nuclear androgen receptor contents of these same specimens, respectively, were 275 +/- 40, 235 +/- 30, 345 +/- 25, and 350 +/- 30; whereas, the values of the cytoplasmic/nuclear receptor content, respectively, were 3.25 +/- 0.55, 3.05 +/- 0.80, 2.50 +/- 0.50, and 2.80 +/- 0.40. Multiway analyses of variance of these cross-sectional data showed that there was no significant difference (p greater than 0.05) between group mean values. This result principally reflects the fact that the families of values for the four tissue groups were highly heterogenous with broad overlap. The results would not appear to be unduly influenced by carcinomatous epithelial cell content of the specimens, because cytoplasmic and nuclear androgen receptor content were not related to specimen carcinomatous epithelial cell content. Paired analyses of receptor content in carcinomatous and noncarcinomatous prostate specimens from the same prostate showed enhanced or unchanged receptor content in 58% (cytoplasmic) and 62% (nuclear) of specimens. Our studies show that cross-sectional analyses of androgen receptor content fail to distinguish carcinomatous prostate from noncarcinomatous prostate. However, paired analyses of these tissues from the same gland identify distinguishing differences. The clinical relevance of these observations remains to be examined.

Cell Nucleus↗
PubMed1982

Uridine 5'-phosphate photohydrate formation in irradiated Escherichia coli 30S ribosomes: photochemistry and relation to ribonucleic acid-protein cross-linking.

Irradiation of aqueous buffered solutions of Escherichia coli 30S ribosomes with doses of 254-nm radiation greater than 10(19) quanta causes formation of uridine 5'-phosphate (UMP) photohydrates in ribosomal 16S RNA (rRNA). The number of molecules of UMP photohydrate formed at doses less than 2 x 10(20) quanta is linearly dependent on dose of absorbed 254-nm radiation. Maximum UMP photohydrate formation is dependent on initial ribosome concentration. When solutions containing 1 A260 unit of 30S ribosomes/mL were irradiated with greater than 2 x 10(20) quanta of 254-nm radiation, maximum photohydrate formation was equal to 47 residues/ribosome. Irradiation of solutions containing 2 A260 units/mL with greater than 7 x 10(20) quanta caused formation of 102 UMP photohydrates/ribosome. These values correspond to conversion of either 15 or 33%, respectively, of the total UMP content of 30S ribosome 16S rRNA to photohydrates. Target theory analysis of UMP photohydration in 30S ribosomes showed that UMP photohydrates are formed by single-hit kinetics from two photochemically distinct precursors. Of the total 16S rRNA UMP residues, 10% was included in the most rapidly (low dose) reacting fraction. The respective photohydration cross sections are 0.014 (low dose) and 0.0095 cm2/muEinstein (high dose) for ribosome solutions containing 2 A260 units/mL. UMP photohydrate content of irradiated 30S ribosomes was compared with that of previous data for the extent of RNA-protein cross-linking at equivalent doses of absorbed 254-nm radiation. This comparison showed that at least two UMP photohydrates form per RNA-protein cross-linking event in 30S ribosomes irradiated with a dose of 254-nm radiation (1.5 x 10(19) quanta), which causes cross-linking of only three ribosomal proteins to 16S rRNA.

Bacterial Proteins↗
PubMed1982

Hormone receptors of the baboon cardiovascular system. Biochemical characterization of aortic and myocardial cytoplasmic progesterone receptors.

We used the synthetic progestin R5020 (17 alpha, 21-dimethyl-19-norpregna-4,9-diene-3,20-dione) to characterize cytoplasmic progesterone receptors in baboon (Papio sp.) aorta and myocardium. The relative ability of selected steroids to inhibit binding of radiolabeled R5020 to aortic cytoplasmic progesterone receptors was radioinert R5020, 1.0; progesterone, 0.31; triamcinolone acetonide, 0.06; testosterone, 0.002; estradiol-17 beta, 0.01; and cortisol. 0.001. The relative ability of these same steroids to inhibit binding of radiolabeled R5020 to myocardial cytoplasmic progesterone receptors was, respectively, 1.0, 0.58, 0.21, 0.01, 0.01, and 0.001. Both aortic and myocardial cytoplasmic progesterone receptors migrated as macromolecules with a sedimentation coefficient of 8-9S on low ionic strength linear sucrose gradients. Cytoplasmic binding of R5020 was inactivated by incubation of 37 degrees C. Saturation analysis at 2 degrees C showed aorta and myocardium, respectively, contained 41.6 +/- 16.1 (mean +/- SD) and was 14.0 +/- 2.8 fmol R5020 binding sites/mg cytosol protein. The dissociation constant for R5020 was 2.8 +/- 1.2 nM, aorta, and 2.0 +/- 1.1 nM, myocardium. The presence of progesterone receptors in baboon cardiovascular tissues suggests that progestins may directly influence cardiovascular tissue function.

Animals↗
PubMed1982

Human prostate androgen receptor quantitation: effects of temperature on assay parameters.

When cytoplasmic extracts of human prostatic tissues were split to permit quantitation of total androgen receptor (RCT) content by saturation analysis at 15 degrees and 2 degrees, we observed that 30% (10 of 32) of the specimens yielded statistically increased values for RCT following incubation at 15 degrees as compared to 2 degrees. Considering only those specimens (13 of 32) showing statistically differentiated RCT yield, 77% (10 of 13) yielded greater RCT content following incubation at 15 degrees. The families of association constants (Ka) obtained for RCT determinations at 2 degrees and 15 degrees were not statistically differentiated. The increased yield of RCT content determined at 15 degrees was 95% (mean) and 20 to 350% (range). Nuclear androgen receptor content determined at 15 degrees was greater for 25% (2 of 8) of the patient specimens when compared to split determinations performed at 2 degrees. Incubation of nuclear extracts at 15 degrees resulted in a significant 3-fold reduction in receptor Ka for methyltrienolone (R1881). This did not appear to affect assay precision. These studies showed that incubation at 15 degrees is preferable to incubation at 2 degrees for quantitation of RCT and nuclear androgen receptor content by saturation analysis. Single saturating dose determinations of RCT consistently yielded underestimates. The extent of underestimate was variable from specimen to specimen and was both ligand concentration and assay temperature dependent. Our data suggest that results of single saturating dose determinations of RCT require cautious interpretation.

Cell Nucleus↗
PubMed1981

AXC rat prostatic adenocarcinoma: characterization of cells in culture.

We have described the establishment of AXC rat prostatic cancer cells in continuous culture. When injected into isogeneic male rats, these cells produce prostatic adenocarcinomas. The response of androgen and prolactin receptors and ODC in LSC-AXC prostatic cancer cells and tumors to androgen ablation is indistinguishable from that of ventral prostate. In addition, LSC-AXC prostatic tumors retain levels of secretory acid phosphatase comparable to those of ventral prostate of aged AXC rats. These data demonstrate that LSC-AXC prostatic cancer cells and tumors retain a high degree of differentiation, androgen regulated function. The LSC-AXC prostatic cancer cells and tumors appear to represent a unique model system for combined in vivo and in vitro studies of androgen regulation of prostate cancer cell function.

Acid Phosphatase↗
PubMed1981

Hormone receptors of the baboon cardiovascular system. Biochemical characterization of myocardial cytoplasmic androgen receptors.

Using the synthetic androgen R1881 (17 beta-hydroxy-17alpha-methyl-estra-4, 9, 11-trien-3-one) as probe, we identified cytoplasmic androgen receptors in baboon myocardium. The relative binding affinity of selected steroids for the androgen receptor was R1881, 100%; 5alpha-dihydrotestosterone, 32.6%; testosterone, 29.6%, progesterone, 7.2%; R5020, 1.0%; and estradiol-17beta, 5.8%. The androgen receptor migrated on low ionic strength linear sucrose density gradients as a macromolecule with a sedimentation coefficient of 8.5S. Saturation analysis performed at 2 degrees C (available sites) showed that the androgen receptor content of baboon myocardial cytoplasmic extracts was 5.9 +/- 1.4 fmol/mg protein and that the dissociation constant for R1881 was 1.16 +/- 0.30 nM. These cytoplasmic androgen receptors are indicated to be physiologically functional by previous autoradiographic studies (McGill et al., 1980; McGill and Sheridan, 1981) that showed localization of radioisotope in nuclei of myocardial fibers following injection of baboons with 5 alpha-dihydrotestosterone.

Animals↗