4-OH tamoxifen does not interfere with bicalutamide inhibitory effects on human prostatic cancer cells in vitro.

BACKGROUND: The present study was aimed at investigating the effects of the co-administration of 4-OH Tamoxifen (4HT) and bicalutamide (BIC) on the human prostate cancer cell line LNCaP in vitro. MATERIALS AND METHODS: The LNCaP FGC prostate cancer cell line was grown in vitro within a three-dimensional matrix formed by collagen gel under dihydrotestosterone (DHT) (0.1 nM) stimulation. Cells were incubated in the presence either of BIC at escalating concentrations (1 nM; 100 nM; 10 microM) or 4HT Tamoxifen (10 nM; 100 nM) or both compounds at the different concentrations studied. The cells were incubated for 144 hours, and growth was evaluated in non trypsinised cells by crystal violet vital dye staining assay. RESULTS: BIC appeared to exert a dose-dependent inhibitory action, with the maximum inhibitory effect achieved by the 10 microM concentration. A comparable inhibitory effect was also observed after exposure to 4HT at both doses tested. No statistically significant interference was observed when BIC was combined with 4HT. CONCLUSION: 4HT, even at the higher concentration employed here, showed no major interference with the inhibitory effects of BIC.

Pervaporation-gas chromatography coupling for slurry samples. Determination of acetaldehyde and acetone in food.

The use of pervaporation for the removal of volatile species from slurry samples, with a full automated introduction of the sample into the lower chamber of the pervaporation unit prior to their individual separation and determination by gas chromatography-flame ionisation detection, is presented for the first time. For this purpose, the upper chamber of the pervaporator is situated in the loop of an HPLC injection valve and the only requirement of the experimental setup for being used with slurries is to have adequately sized diameters for the units of the dynamic manifold assisting the donor chamber in order to avoid clogging by the suspended particles. The method developed was applied to the determination of acetaldehyde and acetone in food samples with different solids contents, such as yoghurt, Actimel and different kind of juices.

Characterization of lymphocyte subsets in rhesus macaques during the first year of life.

Establishing reliable phenotypic data sets from the analysis of peripheral blood lymphocytes of normal animals is required to assess disease states. The rhesus macaque animal model is well established with respect to adult animals, but limited data are available that characterizes lymphocyte subsets in normal neonates. To address this, we used four-color flow cytometric analysis to follow phenotypic changes in 29 normal rhesus animals through their first ten months of life. From birth to 44 wk of age, the white cell count and absolute lymphocyte count were both elevated compared to adults. CD4+ cells constituted over 80% of all T cells at birth, a percentage that declined gradually over the first 12 wk of life, coincidental with increases in the percentages of CD8+ T cells, CD3-8+ natural killer cells and CD20+ B cells. This difference in relative frequency of CD4 and CD8 results in a significant skewing of CD4:CD8 ratio from 0.7:1 in adults to 3.5:1 in neonates. In addition, the predominant population of T lymphocytes consisted of CD45RA+CD62L+ naive cells. This subset continues to be the predominant phenotype for at least the first year of age. After birth the expression of activation markers (CD25) increased particularly on CD4+ T cells, although these levels generally reached a frequency similar to that observed in adults between 12 and 20 weeks after birth. These results are similar to those seen in humans and further confirm the reliability of the rhesus macaque animal model to study human diseases.

17 beta-hydroxysteroid oxidoreductase activity in intact cells significantly differs from classical enzymology analysis.

This paper summarizes our most recent results of steroid enzyme studies on cultured breast and endometrial cancer cells. It deals mainly with estrogen 17 beta-hydroxysteroid oxidoreductase (17 beta HSOR) activity, which presides over estradiol (E2) and estrone (E1) interconversion, a major metabolic pathway of estrogens. Assessment of either the oxidative or reductive component of 17 beta HSOR was carried out on intact cells by means of an original approach based on reverse phase-high performance liquid chromatography and radioactive detection on line. This system allows the continuous monitoring of both precursor degradation and formation of several radiometabolites to assess rates and direction of steroid metabolism. Overall, hormone-responsive, estrogen receptor (ER)-positive cells, regardless of whether they were derived from breast (MCF7) or endometrial (Ishikawa) tumor tissues, showed a prevalence for reductive metabolism (E1-->E2), whilst oxidative pathways (E2-->E1) were largely dominant in non-responsive, ER-poor mammary (MDA-MB231) and endometrial (HEC-1A) cells. The above estimates of 17 beta HSOR activity were at variance with those obtained using the classical enzymology approach, not only in quantitative terms (being markedly lower using intact cell analysis), but also because the prevalent direction of estrogen metabolism was often reversed. Although striking methodological differences may well account for this discrepancy, intact cell analysis is undoubtedly more similar to the in vivo state than the artificial requirements of classical enzymology procedures.

Evidence for soluble and nuclear site I binding of estrogens in human aorta.

The purpose of this study was to establish the estrogen receptor (ER) expression and content in human aorta fragments removed at the time of by-pass surgery. To this end, we adopted a radioligand binding assay to evaluate either soluble (S) or nuclear (N) ER using dextran-coated charcoal (DCC) and filtration methods, respectively. To better define the intratissular distribution and content of ER, we also measured the presence of a 27 kDa heat shock protein (HSP27), a well established ER-associated protein, using D5 monoclonal antibody. Finally, we analysed the different molecular isoforms of both S and N ER using size exclusion-high performance liquid chromatography (SE-HPLC). High affinity (type I) sites of estrogen binding were detected in 17 out of 19 samples in either S or N fraction, although only 9 out of 19 cases displayed site 1 ER in both cell compartments. ER levels in aortic tissues, detected by radioligand method, compare well with those we have found in other hormone-sensitive human cancer tissues and cells. SE-HPLC analysis revealed two main receptor isoforms in the soluble fraction, having 65 kDa and 18 kDa molecular mass, while a minor component of 29 kDa was also found; the nuclear fraction displayed again two major components of 38 and 23 kDa. Using the HSP27 immunohistochemistry we observed a major staining occurring in smooth muscle cells (SMC), with an increasing intensity towards the lumen. All samples, including the ER negative ones, exhibited some degree of histochemical staining. Using an arbitrary cut-off value, 7 out of 12 samples displayed a highly positive staining, 6 of which showed nuclear ER. Furthermore, SE-HPLC separation indicated the presence of a 64.9 kDa component in the soluble fraction, according to the well known relative molecular mass of ER. Following HSP27 immunohistochemistry, the overall staining intensity in aortic SMC approaches that seen in endometrial and breast epithelia, whilst the muscle ER content is generally lower. Although our data are compatible with a direct role of estrogens in arterial function, the extent of the link with arterial disease remains to be established.

Presence of estrogen-binding sites on macrophage-like synoviocytes and CD8+, CD29+, CD45RO+ T lymphocytes in normal and rheumatoid synovium.

OBJECTIVE: To study the presence of estrogen-binding sites (EBS) in the synovial tissues of male and female patients with rheumatoid arthritis (RA) and in age- and sex-matched healthy controls. METHODS: Both type 1 (high affinity, low binding capacity) and type 2 (reduced affinity, higher binding capacity) EBS were investigated in both soluble and nuclear fractions of homogenized synovial tissue samples by a dextran-coated charcoal method. To determine what type of synovial cell was positive for EBS, cryosections of synovial tissues were immunostained with a specific monoclonal anti-estrogen receptor antibody (anti-ER MAb) using both immunofluorescence and immunoperoxidase techniques. Double immunostaining with the anti-ER MAb and with specific MAb to detect different macrophage antigens (Ber-MAC3, MAC387, CD68) and CD8+ T cell subsets (CD29+, CD45RO+ and CD29-, CD45RO-) was performed. RESULTS: Higher affinity EBS were found mostly in nuclear cell fractions of either RA or control synovial tissues (28 of the 33). These EBS were present to a lesser extent in soluble cell fractions (11 of the 33). Immunostaining showed the estrogen receptor-positive cells to be the macrophage-like synoviocytes and the CD8+, CD29+ T cells both in RA and in control synovial tissues. Higher nuclear content of EBS was consistent with more intense nuclear staining of synoviocytes and T cells. CONCLUSION: It is conceivable that the immunomodulatory activity exerted by estrogens is at least partly mediated through their interaction with EBS that are present on macrophage-like synoviocytes, functioning as antigen-processing and antigen-presenting cells, and on antigen-experienced (memory) CD8+ T lymphocytes (CD29+, CD45RO+).

Soluble and nuclear type I and II androgen-binding sites in benign hyperplasia and cancer of the human prostate.

This paper presents an approach for the assessment of the androgen receptor (AR) status in benign prostatic hyperplasia (BPH) and prostate cancer (PCa) tissues. Evaluation of AR was carried out in both soluble and nuclear fractions by a standard competition method, using tritiated mibolerone as radioligand. Based on our experience with breast and endometrial cancer, this approach focused on both type I (high affinity, low capacity) and type II (reduced affinity, higher capacity) binding sites, aiming mainly at establishing a putative "functional" receptor mechanism, i.e., the presence of type I AR in both cytosol and nucleus. Ancillary studies were carried out to exclude a potential overestimation of the AR content by interference with other steroid receptors, namely, progesterone (PgR) or glucocorticoid (GcR) receptors. Results showed that the interaction by PgR or GcR upon AR measurement was not relevant. The distribution of AR, namely the percent of positivity either in a single or in both cell compartments, was not significantly different in BPH (N = 32) or PCa (N = 24) tissues. For type I binding, the percent of positivity in both soluble and nuclear fractions (i.e., the "functional" AR status) was very close to that observed for other endocrine-related tumors, like breast cancer. Concentrations of type I AR appeared significantly higher in PCa than in BPH tissues; this was true for both soluble and nuclear fractions. In contrast, no significant difference was found in type II AR concentrations in either cell fraction.(ABSTRACT TRUNCATED AT 250 WORDS)

Simple approach to measure metabolic pathways of steroids in living cells.

A simple, rapid approach to the study of conversion rates and metabolic patterns of the steroids testosterone and estradiol is presented. It includes an optimized isocratic high-performance liquid chromatographic procedure in the reversed-phase mode and radioactive on-line detection. The purpose was to estimate the activity of key enzymes of steroid pathways, such as 17 beta-hydroxysteroid dehydrogenase and 5 alpha-reductase, in in vivo conditions. Using this system, we obtained good efficiency and linearity of radio detection, under continuous flow conditions. Sensitivity limits were of the order of 50 and 70 cpm for [3H]estradiol and [14C]estrone, respectively, even though the efficiency was quite dissimilar (17.3% versus 56.2%). The applicability of this approach to studies of steroid metabolic pathways in growing cancer cells in culture is illustrated with examples of the conversion rates of both testosterone and estradiol. The high reproducibility (coefficients of variation of 2.7 and 5.1% for 3H and 14C, respectively) and good extraction efficiency (ranging from 86 to 94%) indicate the feasibility and reliability of this approach.

Prostate long-term epithelial cell lines. Biological and biochemical features.

This review reports studies on long-term prostate cell lines using multiple experimental approaches. The main goal was to investigate the metabolism of testosterone (T) through in vitro conversion rates. Extensive studies were also carried out on growth curves, tritiated thymidine incorporation, and morphometry by either hormone-responsive or hormone-unresponsive, normal and neoplastic human (PC3 and DU-145) and canine (CAPE and CPA) cell lines. All of them were characterized for their content of both soluble and nuclear androgen receptors. Receptor studies at site I binding in both soluble and nuclear fractions were carried out to establish the hormone sensitivity status of cells. In two prostate epithelial cells, steroid metabolic conversions in vitro show predominantly an oxidative metabolism of T, forming mainly androstenedione. Conversion rates were greater than 50% in the first 24 hours and still higher after 72 hours. At the same time and under exactly the same experimental conditions, the other cells showed metabolic pathways in which reductive metabolism prevails, dihydrotestosterone (DHT) being the prevalent metabolite. Different metabolic patterns of steroids of several cell lines relate to the hormone sensitivity status of the cells; steroid receptor-endowed cells are maintaining higher levels of unconverted precursor than are receptor-empty cells. In fact, hormone-sensitive cells, such as cancer canine CPA and human DU-145, produced DHT early through slowly converting T. On the contrary, unresponsive cells such as human cancer cells PC3 and normal canine CAPE quickly metabolize T, but DHT formation was not observed. These significant differences between cells are highly reproducible provided the proportion between cell number and molar concentration of precursors is constant. Differences we observe cannot be attributed to different experimental conditions. Cell viability, extraction efficiency, and all other parameters used for monitoring cell growth kinetics do not substantiate these reported significant differences in metabolic abilities of cells. The divergent steroid metabolic pathway we observe in different prostate long-term cells appears to be an intrinsic, consistent, highly reproducible property of each cell line.

Do multiple oestrogen receptor assays give significant additional information for the management of breast cancer?

In 101 breast cancer patients, measurement of oestrogen receptor status in multiple biopsies across a tumour reveals a highly significant difference in the proportion of patients remaining either disease-free (P less than 0.04) or alive (P less than 0.005), when those with uniformly receptor positive (++) primary tumours are matched with clinically comparable patients whose tumours were homogeneously receptor negative (--). Mean follow-up time was 85 months. The prognostic value of this discriminant is particularly striking in the 53 patients with involved nodes at presentation. Of these, 13 were (++) and seven remain alive of whom six are disease-free, whereas 24 of the 29 (--) patients are dead. These results further suggest that receptor assay on a single homogenate gives less clinical information than do assays on multiple biopsies across the tumour. For patients with involved nodes, clinical management may best be decided after determination of 'macroheterogeneity'.

Soluble and nuclear oestrogen receptor status of advanced endometrial cancer in relation to subsequent clinical prognosis.

Both soluble and nuclear oestrogen receptors have been measured in at least two separate sections from 72 endometrial cancers and 12 normal endometria. Concentration of oestrogen receptor is shown to be, in our hands, more meaningful when expressed per unit DNA than per unit protein, whether for soluble or nuclear receptor. Endometrial cancer cells from the central part of the tumour are shown to be receptor negative more frequently than those from peripheral tumour. Thus, in large cancers, biopsies from different areas are required before a tumour can be correctly designated as receptor positive, heterogeneous or receptor negative. The intratumoral variation of receptor status may relate to poor prognosis, since patients with homogeneous receptor-positive disease survive significantly longer than those with tumours showing either heterogeneous distribution of receptor or homogeneous absence of receptor. Intratumoral variation in receptor status is found to be more common in the group of patients who are within 7 years of their menopause, than in older patients.

Estrone conversion rates by human endometrial cancer cell lines.

Studies on estrone metabolism by long term human endometrial cancer HEC-1A and Ishikawa cell lines are reported. These cell lines grow well in epithelial mono or plurilayer form, as previously reported. Ishikawa cells appear to be estrogen responsive whereas HEC-1A appear non responsive. In our experience Ishikawa cells show high affinity--low capacity estrogen binding sites in both soluble and nuclear fractions of the same range of ZR 75-1 and of MCF7, but HEC-1A cytosols gave Kd values in the order of 10(-8)-10(-9). These values are probably more representative of estrogen receptors of low affinity-high capacity (site II) and this is in agreement with previous results regarding their poor response to estrogens. These two different endometrial cancer cell lines exhibit at the same time, common and quite dissimilar metabolic patterns of estrogens. In fact, metabolic conversion studies carried out after 24th incubation at not far from physiological concentrations by using high pressure liquid chromatography in reverse phase mode plus "on line" radioactive detection showed: Both these well established cell lines are fast growing in culture with sufficient morphological or biochemical stability, at least during a limited number of passages and appear a useful material for studies on steroid metabolism. In both, estradiol (E2) and estrone (E1) were most part of converted products (more than 95%); negligible amounts of other radio-metabolites were observed. Quite different conversion rates of E1 to E2 have been shown by HEC-1A cells (6 times or more), with respect to Ishikawa.

Steroid profiles and optimization of high-performance liquid chromatographic analytic procedure.

This paper presents a short review of the results obtained to date in our laboratory, with respect to the studies of steroid excretion profiles in both breast and endometrial cancer patients, by using gas-liquid chromatographic analysis. These data demonstrate the importance of minor estrogens, including catechol estrogens, and of their ratios with the classical ones, in studies of steroid metabolism in both breast and endometrial cancer. New data concerning postmenopausal endometrial cancer are consistent with our previous observations and demonstrate the necessity of measuring these steroids directly in tumors and examining patterns of metabolism in vitro. In order to analyze steroid metabolic patterns in vitro, however, high-performance liquid chromatography rather than gas-liquid chromatography methods are preferable on account of their selectivity, specificity, sensitivity and capacity to handle labile materials. With the aim of providing methods suitable for the complete resolution and analysis of these complex natural mixtures a method of computer-aided optimization of HPLC has been developed and its practical utility has been tested.

Inhibition of prostaglandin synthetase in human rectal mucosa.

Miniaturised methods have been used to construct dose-response curves for the effects of inhibitory drugs on prostaglandin synthesis using individual rectal biopsies obtained from patients with ulcerative colitis. The potency of different drugs has been compared. Sulphasalazine, 5 amino salicylic acid (5-ASA) and N-acetyl 5-ASA inhibited prostaglandin synthesis at high concentration, but sulphapyridine and prednisolone did not. Indomethacin and flurbiprofen were considerably more potent inhibitors. These data imply that sulphasalazine does not act by simple inhibition of prostaglandin synthesis but leave open the possibility that sulphasalazine or 5-ASA may be inhibitors of the synthesis of related lipoxygenase products.

Intra-tumoural variation of oestrogen receptor status in endometrial cancer.

Soluble and nuclear oestrogen receptor status was determined in both the central and peripheral portions of tumour for 37 cases of adenocarcinoma of the endometrium. Of these, 29 had functional receptor in the peripheral biopsy, but only 19 retained functional receptor in the centre. Six of the 10 patients whose tumours showed this difference came from the group of 12 patients who were immediately post-menopausal (4.50 +/- 1.45 y post-menopausal age). Receptor status was not related to tumour classification into histological grades I and II. However, receptor-negative central biopsies were significantly more likely (P less than 0.05) to be Grade III. Early relapse was also related to a receptor-negative central biopsy.

Breast cancer: a comparison of response to endocrine therapy and oestrogen excretion patterns including unusual metabolites.

The urinary excretion patterns of oestrogen metabolites, including unusual metabolites, were determined by gas chromatography and mass spectrometry for 63 women with advanced breast cancer and 39 normal postmenopausal women. The concentration of total unusual metabolites excreted was found to be an excellent discriminant between breast-cancer patients and controls (P less than 0.0001). Discrimination between responders and non-responders to endocrine therapy was attempted, using several different indices. Of these, the ratio of Classical Oestrogens to Unusual Metabolites (CE/UM) proved a fair discriminant, but the product of this ratio and the oestriol ratio (CE/UM x E3R) was much the best discriminant. This product, termed a Pattern Index, has considerable potential, not only as a discriminant for selecting therapy, but also as a rapid index of patient response to that therapy.

Blocking plasma factors of migration inhibition factor production in patients with cervical carcinoma. A possible role in vivo.

The blocking activity was studied of plasma from patients with cervical carcinoma in a model of migration inhibition factor (MIF) production by normal human leukocytes. At the same time, the patients' in vivo (intradermal reactivity) and in vitro (MIF assay) responses were studied with two common antigens (streptokinase-streptodornase and purified protein derivative). The plasma of 15 of 27 patients with carcinoma was capable of blocking the MIF test of human normal leukocytes. Twelve of 15 patients with blocking factor in their plasma had no or only a slight in vivo response, although they had a good in vitor response. Two patients had blocking factor without any in vivo or in vitro response. Six patients who had in vitro responses and slight or no in vivo responses had no plasma blocking activity. Three patients had neither in vivo nor in vitro responses and lacked blocking activity in their plasma.