Fibroblastic colonies, each of which is derived from a single precursor cell (CFU-F), are formed when suspensions of marrow cells are cultured in vitro. The ability of marrow CFU-F to differentiate in vitro was investigated using the expression of alkaline phosphatase activity as a marker for osteogenic differentiation. In cultures of rabbit marrow cells the colonies formed varied in size, morphology and expression of enzyme activity, indicating that marrow stromal CFU-F are a heterogeneous population. Growth and differentiation of marrow CFU-F can be modified in vitro. Epidermal growth factor increased average colony size and reduced clonal expression of alkaline phosphatase activity to very low levels. Hydrocortisone activated the osteogenic differentiation programme within the cellular progeny of a wide spectrum of CFU-F. The results support the possible development of in vitro clonal methods for the study of differentiation and regulation of the osteogenic and other fibroblastic cell lines of the marrow stromal system.

The present study was undertaken to determine what, if any, differential effect various commonly used corticosteroid preparations had on the numbers and specific functions of lymphocyte subpopulations when these agents were administered in equivalent pharmacological dosages. Normal volunteers received a single dose of either 320 mg of hydrocortisone intravenously, 80 mg of prednisone orally, or 12 mg of dexamethasone orally. There was a marked lymphocytopenia and monocytopenia maximal 4-6 hr following administration of all three corticosteroid preparations with almost identical kinetics and degree of fall in total cell numbers as well as proportions of thymus-derived and bone marrow-derived lymphocytes. Hydrocortisone and prednisone caused only a slight suppression of phytohaemagglutiinin (PHA) induced lymphocyte blastogensis which could be reversed at supra-optimal concentrations of PHA. On the contrary, dexamethasone administration casued a marked suppression of PHA responses which was not reversed by supra-optimal PHA stimulation. In addition, hydrocortisone and prednisone administration did not suppress non-specific PHA-induced cellular cytotoxcity, while dexamethasone caused a marked suppression (P less than 0.001) of cytotoxicity. These studies show that although equivalent anti-inflammatory doses of these three corticosteroid preparations cause almost identical suppression of the numbers of circulating lymphocyte populations, they have a differential effect of the numbers of circulating lymphocyte populations, they have a differential effect on a certain in vitro functional correlates of cell-mediated immunity.

OBJECTIVE

The aim of this study was to evaluate the role of metronidazole and tobramycin as an adjunct to corticosteroids in acute, severe ulcerative colitis.

METHODS

Thirty-nine consecutive patients with severe ulcerative colitis were randomized on admission to the hospital to receive intravenously either metronidazole (0.5g tid) and tobramycin (4 mg/kg tid) (n = 19), or placebo (n = 20). In addition, they were given parenteral nutrition, intravenous hydrocortisone (100 mg qid) and hydrocortisone enemas (100 mg bid). All patients were assessed after 10 days of continuous treatment, or at any time a severe complication occurred.

RESULTS

Twelve of 19 patients (63.15%) treated with antibiotics and 13/20 patients (65%) with placebo showed substantial improvement. Seven patients in each group did not improve (n = 9), or developed complications (n = 5) and underwent emergency colectomy without perioperative deaths or late deaths.

CONCLUSIONS

These results do not support the routine use of intravenous tobramycin and metronidazole in the treatment of severe ulcerative colitis.

Prolonged inactivity associated with bed rest in a clinical setting or spaceflight is frequently associated with hypercortisolemia and inadequate caloric intake. Here, we determined the effect of 28 days of bed rest (BR); bed rest plus hypercortisolemia (BRHC); and bed rest plus essential amino acid (AA) and carbohydrate (CHO) supplement (BRAA) on the size and function of single slow- and fast-twitch muscle fibers. Supplementing meals, the BRAA group consumed 16.5 g essential amino acids and 30 g sucrose at 1100, 1600, and 2100 h, and the BRHC subjects received 5 daily doses of 10-15 mg of oral hydrocortisone sodium succinate throughout bed rest. Bed rest induced atrophy and loss of force (mN) and power (muN.FL.s(-1)) in single fibers was exacerbated by hypercortisolemia where soleus peak force declined by 23% in the type I fiber from a prevalue of 0.78 +/- 0.02 to 0.60 +/- 0.02 mN post bed rest (compared to a 7% decline with bed rest alone) and 27% in the type II fiber (1.10 +/- 0.08 vs. 0.81 +/- 0.05 mN). In the BRHC group, peak power dropped by 19, 15, and 11% in the soleus type I, and vastus lateralis (VL) type I and II fibers, respectively. The AA/CHO supplement protected against the bed rest-induced loss of peak force in the type I soleus and peak power in the VL type II fibers. These results provide evidence that an AA/CHO supplement might serve as a successful countermeasure to help preserve muscle function during periods of relative inactivity.

The diurnal variation in thyroidal iodine release previously observed in euthyroid subjects appears to correlate with variations in serum immunoassayable thyrotropin (TSH). The hypothesis is advanced that this diurnal rhythm seems to be primarily regulated by a negative feedback action of circulating hydrocortisone. The administration of maintenance doses of hydrocortisone to patients with primary adrenal insufficiency and pharmacological doses to euthyroid subjects was accompanied by an acute suppression in both thyroidal iodine release and serum TSH values. An escape from glucocorticoid suppression was observed to occur in 2 or 3 days with the resumption of a near-normal thyroidal iodine release rate but was accompanied by a dampening or absence of the normal diurnal rhythm. Withdrawal of pharmacological doses of glucocorticoids in euthyroid subjects and maintenance doses in primary hypoadrenal patients was accompanied by transient stimulation of both serum TSH and thyroidal iodine release values. The study of a patient before and after cryohypophysectomy indicated that the rebound response in thyroid release after steroid withdrawal may be a useful testing procedure to indirectly assess the hypothalamicpituitary reserve capacity of TSH.

In order to isolate and characterize genes whose expression may be altered in breast malignancy, we screened a cDNA library with a polyclonal anti-serum against breast-cancer-metastasis membranes and isolated several immunopositive clones. One of these, AJ1, was analyzed in detail and found to be expressed at varying levels as a 3.3-kb mRNA in all of 143 breast cancers. High expression was associated with lymph-node involvement (p = 0.03). Comparison between high- and low-expressing groups showed a significant difference at 4 and 6 years for both overall (p = 0.004 and p = 0.002 respectively) and disease-free (p = 0.0001 and p = 0.04 respectively) survival, but not at 11 years. AJ1 was expressed at much lower levels in non-malignant biopsies as compared with malignant tissue (p = 0.001). Expression was observed in breast-cancer cell lines MCF-7, ZR-75-1, T47D, MDA-MB-231 and HBL 100. Partial sequence analysis of the 620 bp clone showed complete homology with human heat-shock protein 89 alpha. In addition to being heat-inducible in all the breast cell lines examined, AJ1 levels were increased by estradiol (blocked by cyclohexamide and tamoxifen), EGF, oxytocin and vasopressin in a time-dependent manner in MCF-7 cells and by estradiol, EGF, prolactin and hydrocortisone in T47D cells. In MDA-MB-231 cells, EGF caused down-regulation of AJ1 mRNA levels. The increasing evidence for the association of heat-shock proteins with steroid receptors suggests that AJ1 may play an important role in the control of estrogen-receptor transcriptional activity in breast cancers.

OBJECTIVE

The conventional replacement therapy in Addison's disease (AD) does not restore the normal diurnal cortisol rhythm. We explored the feasibility and safety of continuous s.c. hydrocortisone infusion (CSHI) as a novel mode of glucocorticoid replacement therapy.

METHODS

Seven patients with AD were treated with CSHI in an open-labelled clinical study for up to three months. Adequacy of glucocorticoid replacement was assessed by 24 h blood and saliva sampling in one patient and by salivary cortisol day curves in six outpatients. Subjective health status was monitored by the Short Form-36 questionnaire.

RESULTS

CSHI re-established the circadian variation and normal levels of cortisol in the patients, with minor day-to-day variation. Most of the patients could reduce their glucocorticoid dose considerably without adverse reactions. The treatment was well tolerated and positively evaluated by the patients.

CONCLUSIONS

CSHI is technically feasible and safe in patients with AD. A daily dose of approximately 10 mg/m(2) body surface area/day restores the circadian variation and normal levels of salivary cortisol in most patients, which is close to the estimated daily requirement. We hypothesise that selected patients will benefit from restoration of the circadian cortisol rhythm.

Adrenal insufficiency, primarily presenting as an adrenal crisis, is a life-threatening emergency and requires prompt therapeutic management including fluid resuscitation and stress dose hydrocortisone administration. Primary adrenal insufficiency is most frequently caused by autoimmune adrenalitis, and hypothalamic-pituitary tumors represent the most frequent cause of secondary adrenal insufficiency. However, the exact underlying diagnosis needs to be confirmed by a stepwise diagnostic approach, with an open eye for other differential diagnostic possibilities. Chronic replacement therapy with glucocorticoids and, in primary adrenal insufficiency, mineralocorticoids requires careful monitoring. However, current replacement strategies still require optimization as evidenced by recent studies demonstrating significantly impaired subjective health status and increased mortality in patients with primary and secondary adrenal insufficiency. Future studies will have to explore the potential of dehydroepiandrosterone replacement and modified delayed-release hydrocortisone to improve the prospects of patients with adrenal insufficiency.

Stress promotes a shift from goal-directed action-outcome learning toward habitual stimulus-response learning. This shift is mediated by an interaction of noradrenergic activity and glucocorticoid stress hormones. In the present experiment, we examined the neural correlates of the stress (hormone)-induced shift from goal-directed to habit learning in the human brain. Healthy participants were administered hydrocortisone, the α2-adrenoceptor antagonist yohimbine, or both before they were trained in two instrumental actions leading to two distinct food rewards. After training, one of the rewards was devalued by feeding participants to satiety on that food. Finally, participants were presented the two instrumental actions in extinction. We collected functional magnetic resonance images both during instrumental training and during extinction testing. Our behavioral data confirmed that the simultaneous administration of hydrocortisone and yohimbine renders instrumental behavior insensitive to the outcome devaluation (and thus habitual), whereas hydrocortisone or yohimbine alone have no such effect. At the neural level, the combined administration of hydrocortisone and yohimbine reduced the sensitivity of the orbitofrontal and medial prefrontal cortex to changes in outcome value. Brain areas that have been previously implicated in habit learning were not modulated by hydrocortisone and yohimbine. These findings suggest that concurrent glucocorticoid and noradrenergic activity disrupts the neural bases of goal-directed action and thus renders behavior habitual.

In an attempt to prevent in utero virilization of female fetuses with 21-hydroxylase deficiency, six mothers at risk were treated with either hydrocortisone (n = 1) or dexamethasone (n = 5) in early pregnancy. Treatment was continued to term in the two pregnancies in which the diagnosis of an affected female fetus was confirmed. In patient 1 (hydrocortisone treatment) fetal adrenal suppression was only partial but the external genitalia were only slightly abnormal. In patient 2 (dexamethasone treatment) fetal adrenal suppression was achieved and the external genitalia were normal at birth. These encouraging results open a new prospect for treating congenital adrenal hyperplasia in utero.

Although studies of infective lung diseases have demonstrated that Haemophilus influenzae is a major pathogen, the mechanisms underlying pathogenesis by this organism are not clear. We have cultured human bronchial epithelial cells (HBEC) to confluency and have investigated the effect of H. influenzae endotoxin (HIE) on: 1) epithelial permeability, by movement of 14C-bovine serum albumin (14C-BSA) across HBEC and measurement of electrical resistance of HBEC; 2) release of interleukin-6 (IL-6), interleukin-8 (IL-8) and tumour necrosis factor-alpha (TNF-alpha) into the supernatant, by enzyme-linked immunosorbent assay (ELISA); and 3) expression of intercellular adhesion molecule-1 (ICAM-1), by immunofluorescence staining. HIE did not significantly increase the movement of 14C-BSA across HBEC. In contrast, HIE progressively increased the electrical resistance of HBEC, such that this was significant after 24 h. Compared with untreated cells, 10-100 micrograms.ml-1 HIE-treated cells released significantly greater amounts of IL-6, IL-8 and TNF-alpha, after 24 h, which was blocked by 10(-5) M hydrocortisone. Similarly, incubation of HBEC with 10-100 micrograms.ml-1 HIE, significantly increased the total number of ICAM-1 positive cells, which were significantly decreased on incubation of the cells in the presence 10(-5) M hydrocortisone. Conditioned medium from HIE-exposed HBEC lead to significant increase in neutrophil chemotaxis and adhesion to endothelial cells in vitro. These results suggest that HIE may affect epithelial cell function and influence inflammation of the airway mucosa via induction of proinflammatory mediators.

Isolated rat calvaria cells plated at low density in medium supplemented with ascorbic acid and organic phosphate form discrete three-dimensional mineralized nodules having the characteristics of bone. We have studied the effects of glucocorticoids on the formation of bone nodules by these cell populations. Cells isolated from 21-day-old fetal rat calvaria were maintained in vitro for up to 27 days. Dexamethasone (Dex) induced a dose-related increase in the number of nodules formed, with a peak at 10 nM and a half-maximal response at about 1 nM. Dex (10 nM) also significantly increased the size of bone nodules formed (P less than 0.002). High concentrations of Dex (1 microM) did not increase nodule number. In cells in primary culture maintained in medium containing 10 nM Dex, the increase in nodule number was 50-100% over the control value. The effect of Dex was much greater in first subculture cells, where the number of nodules was 600-800% higher than the control value. Dishes collected and quantitated from 12-27 days showed that nodule formation ceased between 15 and 18 days in cultures without Dex, whereas in the presence of Dex the number of nodules increased up to 27 days. Addition of 10 nM Dex only during specific periods resulted in significantly more nodules than in control cultures, but significantly fewer nodules than in cultures constantly exposed to Dex. Cell population doubling times during log phase growth were unaltered, but a significant increase in saturation density (P less than 0.001) was observed with 10 nM Dex. Hydrocortisone also caused an increase in the number of nodules formed, with a maximal effect of 50 nM and a half-maximal response at 8 nM. The results indicate that physiological levels of glucocorticoids stimulate bone nodule formation in long term cell culture by increasing the number of cells forming bone nodules and that maximization of the stimulatory effect of glucocorticoids on bone formation may require constant exposure to low levels of the hormone.

In vitro hydrocortisone in physiologic and pharmacologically attainable concentrations caused a marked enhancement of the PWM-induced PFC response of normal human peripheral blood B lymphocytes. This effect was seen only when hydrocortisone was added within the first 24 hr of culture and only when hydrocortisone and PWM were present together in cultures. Only suprapharmacologic concentrations of hydrocortisone (10(-3) M) were capable of suppressing early B cell activation. Late stages of antibody production and secretion were resistant to suppression by even these extraordinarily high concentrations. Hydrocortisone did not replace the T cell requirement of PWM-induced PFC responses. A single dose of in vivo hydrocortisone (400 mg) to normal adult volunteers did not produce this enhancing effect when PFC responses were measured in vitro in the absence of hydrocortisone. The data strongly suggest that the enhancing effect of hydrocortisone was due not to elimination of naturally occurring suppressor cells, but to a modulation of the triggering signal either directly on the B cell itself or via the balance of positive and negative T cell regulation of B cell activation.

Nitric oxide (NO) has been suggested to be involved in the regulation of osteoclast activity. Since osteoblasts, through the release of various factors, are the main regulators of osteoclastic resorption, first we have investigated whether osteoblast-like cells and fetal mouse long bone explants are able to produce NO. Second, we have assessed the effect of NO on osteoclastic resorption in whole bone cultures. In this study we show that primary rat osteoblast-like cells as well as the clonal rat osteoblast-like cell line UMR-106, stimulated with IFN-gamma together with TNF-alpha and LPS, produce NO, measured as nitrite production. IL-1 alpha enhanced while TGF-beta 2 inhibited TNF-alpha + IFN-gamma + LPS-stimulated NO production in UMR-106 cells dose dependently. Both the cytokines, however, had no effect when given alone. The competitive inhibitor of NO production, NG-monomethyl-arginine (L-NMMA), and cycloheximide abolished the increase in nitrite production induced by TNF-alpha + IFN-gamma + LPS, while hydrocortisone had no effect, as previously reported for chondrocytes. Calciotropic hormones had either no effect [1,25(OH)2D3] or had a small inhibitory effect (parathyroid hormone) on stimulated NO production. Furthermore, we found that in cultured fetal mouse long bone explants the combination of TNF-alpha + IFN-gamma + LPS as well as the NO donor sodium nitroprusside could inhibit osteoclastic resorption, measured as 45Ca release. The inhibition of resorption was prevented by concurrent administration of L-NMMA. Histological evaluation revealed that the TNF-alpha + IFN-gamma + LPS-induced inhibition of 45Ca release was associated with a decrease in the number of tartrate-resistant acid phosphatase-positive osteoclasts. We propose that the NO production by osteogenic cells (osteoblasts and chondrocytes) may represent an important regulatory mechanism of osteoclastic activity especially under pathological conditions characterized by release of bone-resorbing inflammatory cytokines.

The administration of glucagon to rats causes a marked increase in the phosphorylation of a specific serine residue in lysine-rich (f1) histone of liver during a one-hour period following the administration of the hormone. It is proposed that histone phosphorylation is the mechanism by which glucagon, and perhaps other hormones whose actions are mediated by adenosine 3',5'-cyclic phosphate (cyclic AMP), induce RNA synthesis in target tissues. The incorporation of (32)P-phosphate into lysine-rich histone is determined by isolation of a tryptic peptide which contains the phosphorylated serine residue. This peptide is identical to the major tryptic phosphopeptide obtained from lysine-rich histone after phosphorylation in vitro by a purified cyclic AMP-dependent liver histone kinase preparation; the partial sequence Lys-Ala-SerPO(4)(Thr,Ser,Glu,Pro(2),Gly,Val,Ile,Leu)Lys has been determined for the peptide. Hydrocortisone and adrenocorticotrophic hormone do not cause a detectable increase in histone phosphorylation in liver. However, insulin, which like glucagon induces an actinomycin sensitive synthesis of liver enzymes, also causes increased histone phosphorylation.

HeLa cells in culture synthesize metallothionein. To investigate the effects of glucocorticoids on metallothionein synthesis we adapted HeLa cells to growth in a defined medium lacking hydrocortisone. In this defined medium, containing 1.5 x 10(-6)M Zn2+, dexamethasone (10(-6)M) caused a five- to sixfold increase in the synthesis of metallothionein. Progesterone (10(-5)M), a known antagonist of glucocorticoids, inhibited this response by 50 percent.

Interleukin-12 is a recently discovered lymphokine displaying an array of in vitro activities suggesting a major role in protective immunity against infectious agents like viruses. This study provides evidence that IL-12 may also be implicated in the selection of the immunoglobulin isotypes. We show that picomolar concentrations of rIL-12 markedly inhibit the synthesis of IgE by IL-4-stimulated PBMC. The suppression of IgE is observed at the protein and at the mRNA levels, it is isotype specific, and it is abolished by neutralizing anti-IL-12 mAbs. IL-12 may suppress IgE synthesis by: (a) inducing the production of IFN-gamma, a known inhibitor of IgE synthesis and (b) by a novel mechanism which is IFN-gamma independent. The best evidence for this is from studies on IgE synthesis by IL-4-plus hydrocortisone-stimulated umbilical cord blood lymphocytes, which do not produce detectable amounts of IFN-gamma. In such cultures, rIL-12 inhibits IgE synthesis even in the presence of a large excess of neutralizing anti-IFN-gamma mAb.

Proliferation of adult human prostatic epithelial cells in serum-free medium occurs upon the addition of cholera toxin, epidermal growth factor, pituitary extract, and hydrocortisone to basal medium PFMR-4A. Insulin and selenium enhance proliferation and permit growth at lower cell densities. Reducing the level of calcium in the medium dramatically alters morphology and also seems to increase proliferation. Mortal strains of cells derived from normal central or peripheral zone, benign hyperplasia, or cancer respond similarly to growth factors and calcium, but two populations of cancer cells which have been long-lived and may be immortal lines behave differently. GKC-CA cells require serum proteins or high levels of pituitary extract for optimal growth, and neither GKC-CA cells or cells of another cancer line, WB-CA, proliferate well in medium containing reduced levels of calcium. These observations may, however, be a reflection of attachment phenomena rather than of growth responses per se. Growth of cells in serum-free medium has allowed definitive studies of the effects of androgens, and regardless of cell type no response to androgens of prostate epithelial cells under any experimental conditions has been seen.

The differentiation of isolated human cytotrophoblast cells has been studied by staining cells with anti-desmoplakin antibodies, to reveal cell boundaries, and with anti-nuclear antibodies, to reveal nuclei. During the first 24 h after plating in Ham's/Waymouth medium, mononucleated cytotrophoblast cells began to spread and aggregate, forming colonies. This was accompanied by progressive changes in the pattern of desmoplakin staining. In single cells, desmoplakin was dispersed throughout the cytoplasm. As cells aggregated, desmoplakin was redistributed and formed linear, punctate arrays at regions of cell-cell contact, consistent with desmosome formation. A pavement-like staining pattern was maintained even at 5 days. Double staining for desmoplakin and nuclei revealed that most cells within colonies were mononucleated. When plated in a growth medium originally formulated for keratinocytes, cytotrophoblast cells aggregated and formed desmosomes normally. However, after 48 h, cell diameters were increased and nuclei changed from being evenly distributed to forming clusters within large cells, consistent with syncytiotrophoblast formation. While cells grown in Ham's/Waymouth medium for 2 days could be induced to differentiate by switching to keratinocyte growth medium, cells cultured for 5 days before switching were resistant to the differentiation-inducing effects of the keratinocyte medium. Desmosome-type junctions within colonies of trophoblast cells were unstable and, even after 5 days in culture, could be disrupted by lowering the extracellular Ca2+ concentration. While syncytiotrophoblast formation in keratinocyte growth medium (which contains epidermal growth factor, insulin and hydrocortisone) was accompanied by a 15- to 20-fold increase in chorionic gonadotropin secretion, syncytiotrophoblast formation occurred to a similar extent in keratinocyte basal medium (which does not contain these factors) but with only a twofold increase in chorionic gonadotropin release. These results support the notion that biochemical and morphological differentiation of trophoblast are independent events.

Because lymphoid progenitors can give rise to natural killer (NK) cells, NK ontogeny has been considered to be exclusively lymphoid. Here, we show that rare human CD34(+) hematopoietic progenitors develop into NK cells in vitro in the presence of cytokines (interleukin-7, interleukin-15, stem cell factor, and fms-like tyrosine kinase-3 ligand). Adding hydrocortisone and stromal cells greatly increases the frequency of progenitor cells that give rise to NK cells through the recruitment of myeloid precursors, including common myeloid progenitors and granulocytic-monocytic precursors to the NK-cell lineage. WNT signaling was involved in this effect. Cells at more advanced stages of myeloid differentiation (with increasing expression of CD13 and macrophage colony-stimulating factor receptor [M-CSFR]) could also differentiate into NK cells in the presence of cytokines, stroma, and hydrocortisone. NK cells derived from myeloid precursors (CD56(-)CD117(+)M-CSFR(+)) showed more expression of killer immunoglobulin-like receptors, a fraction of killer immunoglobulin-like receptor-positive-expressing cells that lacked NKG2A, a higher cytotoxicity compared with CD56(-)CD117(+)M-CSFR(-) precursor-derived NK cells and thus resemble the CD56(dim) subset of NK cells. Collectively, these studies show that NK cells can be derived from the myeloid lineage.

OBJECTIVE

Increasing evidence indicates that enhanced intratumoral androgen synthesis contributes to prostate cancer progression after androgen deprivation therapy. This phase II study was designed to assess responses to blocking multiple steps in androgen synthesis with inhibitors of CYP17A1 (ketoconazole) and type I and II 5alpha-reductases (dutasteride) in patients with castration-resistant prostate cancer (CRPC).

METHODS

Fifty-seven men with CRPC were continued on gonadal suppression and treated with ketoconazole (400 mg thrice daily), hydrocortisone (30 mg/AM, 10 mg/PM), and dutasteride (0.5 mg/d).

RESULTS

Prostate-specific antigen response rate >> or =50% decline) was 56% (32 of 57; 95% confidence interval, 42.4-69.3%); the median duration of response was 20 months. In patients with measurable disease, 6 of 20 (30%) responded by the Response Evaluation Criteria in Solid Tumors. Median duration of treatment was 8 months; 9 patients remained on therapy with treatment durations censored at 18 to 32 months. Median time to progression was 14.5 months. Grade 3 toxicities occurred in 32% with only one reported grade 4 (thrombosis) toxicity. Dehydroepiandrosterone sulfate declined by 89%, androstenedione by 56%, and testosterone by 66%, and dihydrotestosterone declined to below detectable levels compared with baseline levels with testicular suppression alone. Median baseline levels and declines in dehydroepiandrosterone sulfate, androstenedione, testosterone, and dihydrotestosterone were not statistically different in the responders versus nonresponders, and hormone levels were not significantly increased from nadir levels at relapse.

CONCLUSIONS

The response proportion to ketoconazole, hydrocortisone, and dutasteride was at least comparable with previous studies of ketoconazole alone, whereas time to progression was substantially longer. Combination therapies targeting multiple steps in androgen synthesis warrant further investigation.