Translational offsetting as a mode of estrogen receptor α-dependent regulation of gene expression.

Estrogen receptor alpha (ERα) activity is associated with increased cancer cell proliferation. Studies aiming to understand the impact of ERα on cancer-associated phenotypes have largely been limited to its transcriptional activity. Herein, we demonstrate that ERα coordinates its transcriptional output with selective modulation of mRNA translation. Importantly, translational perturbations caused by depletion of ERα largely manifest as "translational offsetting" of the transcriptome, whereby amounts of translated mRNAs and corresponding protein levels are maintained constant despite changes in mRNA abundance. Transcripts whose levels, but not polysome association, are reduced following ERα depletion lack features which limit translation efficiency including structured 5'UTRs and miRNA target sites. In contrast, mRNAs induced upon ERα depletion whose polysome association remains unaltered are enriched in codons requiring U34-modified tRNAs for efficient decoding. Consistently, ERα regulates levels of U34-modifying enzymes and thereby controls levels of U34-modified tRNAs. These findings unravel a hitherto unprecedented mechanism of ERα-dependent orchestration of transcriptional and translational programs that may be a pervasive mechanism of proteome maintenance in hormone-dependent cancers.

Intraoperative intraocular pressure changes during robot-assisted radical prostatectomy: associations with perioperative and clinicopathological factors.

BACKGROUND: Steep Trendelenburg position (ST) during robot-assisted radical prostatectomy (RARP) poses a risk of increase in intraocular pressure (IOP) in men receiving robot-assisted radical prostatectomy (RARP). The aim of the study was to identify clinicopathological factors associated with increased IOP during RARP. METHODS: We prospectively studied 59 consecutive prostate cancer patients without glaucoma. IOP was measured at 6 predefined time points before, during and after the operation (T1 to T6). RESULTS: Compared with T1, IOP decreased after beginning of anesthesia(T2) (by - 6.5 mmHg, p < 0.05), and increased 1 h after induction of pneumoperitoneum in the steep Trendelenburg position (ST) (T3) (+ 7.3 mmHg, p < 0.05). IOP continued to increase until the end of ST (T4) (+ 10.2 mmHg, p < 0.05), and declined when the patient was returned to supine position under general anesthesia (T5) (T1: 20.0 and T5: 20.1 mmHg, p above 0.05). The console time affected the elevation of IOP in ST; IOP elevation during ST was more prominent in men with a console time of ≥4 h (n = 39) than in those with a console time of < 4 h (n = 19) (19.8 ± 6.3 and 15.4 ± 5.8 mmHg, respectively, p < 0.05). Of the 59 patients, 29 had a high baseline IOP (20.0 mmHg or higher), and their IOP elevated during ST was also reduced at T5 (T1: 22.6 and T5: 21.7 mmHg, p above 0.05). There were no postoperative ocular complications. CONCLUSIONS: Console time of < 4 h is important to prevent extreme elevation of IOP during RARP. Without long console time, RARP may be safely performed in those with relatively high baseline IOP.

Limited significance of repeated long-term radiological and hormonal examination in nonfunctioning adrenal incidentalomas.

PURPOSE: The purposes of the present study were to evaluate growth rate of nonfunctioning adrenal incidentalomas (AIs) and their development to hormonal hypersecretion on follow-up. MATERIALS AND METHODS: A retrospective study was conducted from the electronic medical records. A total of 314 patients were diagnosed with adrenal tumors between 2000 and 2016. After excluding patients who had overt adrenal endocrine disorders or whose adrenal tumors were clinically diagnosed as metastatic malignancies, we investigated 108 patients with nonfunctioning AIs including characteristics, the treatment, the way of follow-up and pathology. RESULTS: Fifteen patients received immediate adrenalectomy because of the initial tumor size or patient's preference. Pathological examination revealed malignancy in 2 patients. In the remaining 93 patients, radiological examinations were performed periodically. Tumor enlargement of ≥ 1.0cm was observed in 8.6% of the patients who were followed up as nonfunctioning AIs with a median follow-up period of 61.5 months (range: 4-192). Eleven patients underwent adrenalectomy. On the pathological examinations, all of the tumors, which showed a size increase, were diagnosed as benign tumors. Regarding the followed up patients without adrenalectomy, only 2.4% of the patients had tumor enlargement during the prolonged follow-up. Furthermore, none of the patients developed hormonal hypersecretion or clinical signs such as obesity, glucose intolerance or poorly controlled hypertension. CONCLUSIONS: Tumor enlargement of AIs did not correlate with malignancy. The value of repeat radiological and hormonal examinations may be limited in the long-term follow-up of patients whose AIs are not enlarged.

A carbon 21 steroidal metabolite from progestin, 20ß-hydroxy-5α-dihydroprogesterone, stimulates the androgen receptor in prostate cancer cells.

BACKGROUND: Clarifying the mechanisms underlying prostate cancer (PC) progression and resistance to androgen deprivation therapy (ADT) is an urgent clinical issue. ADT influences steroidal metabolism in patients with PC and promotes the accumulation of carbon 21 steroids (C21s), such as progestin. Because the enzymes responsible for C21s metabolism are similar to those for androgen metabolism, PC cells may be able to metabolize C21s intracellularly. Therefore, there is a possibility that intracrine C21s are implicated in PC progression and resistance to ADT, and the influence of C21s on PC cells is yet to be elucidated. In the present study, we focused on 20ß-hydroxy-5α-dihydroprogesterone (20ß-OHDHP), a C21s metabolized from progestin, and showed that 20ß-OHDHP is synthesized in PC cells and is able to directly stimulate the androgen receptor (AR). METHODS: LNCaP, VCaP, and DU145 cells, which express a mutant AR (mAR), wild-type AR (wAR), and glucocorticoid receptor (GR), respectively, were incubated in the presence of several agents. After incubation, cell growth was determined by the MTS assay. PSA levels were determined by an enzyme immunoassay, and C21s and androgen levels were measured using liquid chromatography-mass spectrometry. Gene expression was analyzed by quantitative real-time polymerase chain reaction, and steroidal-receptor-related signaling was determined by a reporter assay. RESULTS: We affirmed that 20ß-OHDHP was synthesized from pregnenolone intracellularly in LNCaP and VCaP cells, and 20ß-OHDHP significantly promoted the growth of both cell lines without androgen conversion. 20ß-OHDHP directly stimulated both mAR and wAR. The presence of 20ß-OHDHP was sufficient for the proliferation and survival of LNCaP or VCaP cells, and 20ß-OHDHP promoted cell growth even in the presence of abiraterone. Using DU145 cells, we affirmed that 20ß-OHDHP did not stimulate GR, which has a potential to bypass AR signaling in PC cells promote PC cell growth. CONCLUSIONS: Under ADT, 20ß-OHDHP synthesized intracellularly from accumulated progestin in PC cells may accelerate cell growth via stimulation of both wAR and mAR. This pathway may represent an interesting candidate for targeted therapy.

A multicenter retrospective analysis of sequential treatment of abiraterone acetate followed by docetaxel in Japanese patients with metastatic castration-resistant prostate cancer.

OBJECTIVE: Abiraterone acetate and docetaxel are promising treatment options for metastatic castration-resistant prostate cancer patients. However, the optimal sequencing of these agents is unclear, and no previous reports discuss Japanese metastatic castration-resistant prostate cancer patients. The purpose of this analysis is to reveal the outcomes of Japanese metastatic castration-resistant prostate cancer patients treated with abiraterone acetate followed by docetaxel. METHODS: We retrospectively reviewed Japanese Phase 1 and Phase 2 trials of metastatic castration-resistant prostate cancer patients treated with abiraterone acetate until disease progression and subsequently treated with docetaxel. The primary outcome measure was the rates of prostate-specific antigen declines ≧30 and ≧50%, respectively, with docetaxel. Secondary outcome measures included progression-free survival with docetaxel, and overall survival after initiation of abiraterone acetate and docetaxel. We performed correlation analysis between previous prostate-specific antigen response to abiraterone acetate and subsequent prostate-specific antigen response to docetaxel. RESULTS: We identified 15 patients had experienced disease progression with abiraterone acetate and subsequently were treated with docetaxel. Prostate-specific antigen declines ≧30 and ≧50% with docetaxel were observed in five patients (33%) and two patients (13%), respectively. The median progression-free survival with docetaxel was 3.7 months (95% confidence interval: 2.9-4.6). The median overall survival from initiation of docetaxel and abiraterone acetate were 14.4 months (95% confidence interval: 6.3-22.4), and 25.7 months (95% confidence interval: 20.1-30.7), respectively. No significant correlation was observed between these prostate-specific antigen responses (Pearson r = 0.206, P = 0.46). CONCLUSION: The efficacy of docetaxel in Japanese mCRPC patients that was resistant to abiraterone acetate was modest. The prostate-specific antigen response to previous abiraterone acetate could not predict the efficacy of subsequent docetaxel. Larger prospective trials are needed to validate these findings.

Altered association of interleukin-6 with sex steroids in lipid metabolism disorder in men with prostate cancer receiving androgen deprivation therapy.

BACKGROUND: Interleukin-6 produced in adipose tissue plays a role in lipid metabolism, and also interacts with sex steroids. This study was performed to elucidate the mechanism of lipid metabolism disorder during androgen deprivation therapy (ADT) in terms of the association of interleukin-6 with sex steroids. METHODS: Seventy-two patients with localized prostate cancer were prospectively studied based on their body-composition and blood samples before and after ADT for 6 months. RESULTS: Before ADT, serum interleukin-6 levels were inversely correlated with serum total-testosterone (rs = -0.305, P = 0.009) and dihydrotestosterone (rs = -0.380, P = 0.006) concentrations, but not correlated with adrenal androgen or estradiol levels. Pretreatment interleukin-6 levels were positively correlated with %body fat (rs = 0.349, P = 0.003) and %visceral fat (rs = 0.384, P = 0.001). After ADT, %body fat increased (P < 0.001) and lean body mass decreased (P = 0.036). After ADT, in contrast to the pretreatment relationship, interleukin-6 levels were positively correlated with total-testosterone concentrations (rs = 0.343, P = 0.003), and were positively correlated also with levels of androstenedione (rs = 0.351, P = 0.002) and estoradiol (rs = 0.335, P = 0.004). Interleukin-6 levels were equivalent between before and after ADT (2.02 vs. 2.16 pg/ml, P = 0.205), but the positive correlation between interleukin-6 levels and %body or %visceral fat noted before ADT disappeared after ADT. CONCLUSIONS: Posttreatment interleukin-6 levels had a strong positive correlation with total-testosterone, androstenedione, and estradiol levels, suggesting that a regulation loop may emerge between these sex steroids and interleukin-6 during ADT. The altered association between interleukin-6 and sex steroids is possibly involved in ADT-related lipid metabolism disorder with unchanged interleukin-6 levels despite increased %body fat.

External validation of the UCSF-CAPRA (University of California, San Francisco, Cancer of the Prostate Risk Assessment) in Japanese patients receiving radical prostatectomy.

OBJECTIVE: In 2005, the University of California, San Francisco developed the Cancer of the Prostate Risk Assessment (UCSF-CAPRA) score as a new risk stratification tool. The UCSF-CAPRA, which ranges from 0 to 10 points, consists of five clinical variables, prostate-specific antigen, Gleason score, T stage, percent of positive biopsies and age. The aim of this study was to validate the UCSF-CAPRA score for Japanese prostate cancer patients receiving radical prostatectomy using the contemporary Gleason grading. METHODS: From 1999 to 2010, 211 men who underwent radical prostatectomy were used for validation. Biochemical progression-free survival was calculated using the Kaplan-Meier method and the UCSF-CAPRA and D'Amico risk categories were compared using the log-rank method. The concordance index (c-index) for the UCSF-CAPRA and D'Amico risk classification was calculated. RESULTS: Using the UCSF-CAPRA score, 85 (40.3%), 106 (50.2%) and 20 (9.5%) subjects were stratified as 0-2 points (low risk), 3-5 points (intermediate risk) and 6-10 points (high risk). Using the D'Amico risk criteria, 66 (31.3%), 89 (42.2%) and 56 (26.5%) were stratified as low-, intermediate- and high-risk groups, respectively. The Kaplan-Meier analysis showed that the UCSF-CAPRA divided the patients significantly into each risk category. There was no significant difference between low and intermediate in the D'Amico risk classification. The c-index of the UCSF-CAPRA and D'Amico classification was 0.755 and 0.713, respectively. CONCLUSION: The UCSF-CAPRA is an acceptable risk category tool comparable to that of the D'Amico risk classification for Japanese prostate cancer patients receiving radical prostatectomy in the contemporary Gleason grading era.

Serum prostate-specific antigen levels reflect the androgen milieu in patients with localized prostate cancer receiving androgen deprivation therapy: Tumor malignant potential and androgen milieu.

BACKGROUND: Although androgen deprivation therapy (ADT) has a marked impact on the androgen milieu in vivo and outcomes of prostate cancer (PCa), it remains unclear which parameters reflect the androgen milieu during ADT or whether the milieu is associated with PCa aggressiveness. METHODS: Seventy-two patients with localized PCa were prospectively studied based on their blood samples before and after ADT for 6 months. Serum androgens and related values were measured. RESULTS: Before ADT, there was no correlation between the serum prostate-specific antigen (PSA) and androgen levels. After ADT, the serum PSA levels were correlated with each level of serum testosterone, dihydrotestosterone, androstenedione, dehydroepiandrosterone-sulfate (DHEA-S), and 3alpha-diol G (P < 0.010 in all). Before ADT, patients with Gleason score of > or = 8 were likely to have lower serum testosterone levels than those with Gleason score of < or = 6 (P = 0.058). After ADT, conversely, the testosterone levels in patients with Gleason score of > or = 8 appeared to be higher than in those with Gleason score of < or = 6 (P = 0.060). The serum DHEA-S level was correlated with Gleason score before and after ADT (P = 0.050 and P = 0.040, respectively). CONCLUSIONS: The serum PSA levels well reflect the androgen milieu in localized PCa patients receiving ADT, which can be explained by the Saturation Model and disease control. The androgen milieu in men with high Gleason score PCa is probably less affected by conventional ADT than that in men with low score cancer, which was suggested to be associated with adrenal androgen levels.

Bone metabolic disorder in patients with prostate cancer receiving androgen deprivation therapy (ADT): impact of ADT on the growth hormone/insulin-like growth factor-1/parathyroid hormone axis.

BACKGROUND: Although androgen deprivation therapy (ADT) has been associated with bone loss in patients with prostate cancer, its mechanism remains unclear. The growth hormone (GH)/insulin-like growth factor-1 (IGF-1)/parathyroid hormone (PTH) axis plays a critical role in bone synthesis, but its activity during ADT is also unknown. METHODS: Seventy-one patients with localized prostate cancer, who received ADT, were prospectively studied based on their bone mineral density (BMD) and blood and urine samples at the baseline and after ADT for 6 months. RESULTS: The IGF-1 level was correlated with BMD before ADT (rs = 0.325, P = 0.007), but such a relationship disappeared after ADT (P = 0.565). Following ADT, the serum IGF-1 level increased compared with that at the baseline (22 +/- 6 nmol/L vs. 19 +/- 5 nmol/L, respectively, P < 0.001). The serum PTH level was reduced after ADT (41 +/- 33 ng/L) compared with the baseline (55 +/- 44 ng/L) (P < 0.001), but no change was observed in the serum GH level (P = 0.691). Bone resorption markers such as blood N-telopeptide (NTx), urinary NTx, calcium, and inorganic phosphorus levels increased after ADT (P < 0.001 in all). The ratio of the IGF-1 level after ADT/before ADT was associated with the ratio of the value after ADT/before ADT of alkaline phosphatase (rs = 0.266, P = 0.025) and calcium (rs = 0.242, P = 0.042). CONCLUSION: Despite the unaffected GH and upregulated bone resorption, the serum IGF-1 level was elevated by ADT. The IGF-1 level was correlated with BMD before ADT, but the relationship was disrupted after ADT. IGF-1 or its receptor in the bone may be functionally inactivated during ADT.

Adrenocorticotropic hormone is involved in regulation of androgen synthesis in men receiving androgen deprivation therapy for localized prostate cancer.

PURPOSE: We elucidated the regulatory mechanism of adrenal androgen synthesis and examined the influence of pituitary-adrenal axis activity on prostate specific antigen during androgen deprivation therapy. MATERIALS AND METHODS: A total of 72 patients with localized prostate cancer were prospectively studied based on blood samples before and after androgen deprivation therapy for 6 months. Serum pituitary hormones, androgens and prostate specific antigen were measured using highly sensitive assays. RESULTS: After androgen deprivation therapy serum levels of luteinizing hormone, follicle-stimulating hormone, testosterone, dehydroepiandrosterone sulfate, androstenedione and prostate specific antigen decreased compared with those at the baseline (all values p <0.001). No difference was noted between serum levels before and after androgen deprivation therapy in growth hormone (p = 0.098) and adrenocorticotropic hormone (p = 0.101). Each serum level of luteinizing hormone, follicle-stimulating hormone and growth hormone after androgen deprivation therapy was not correlated with the serum levels of androgens or prostate specific antigen. The serum adrenocorticotropic hormone level after androgen deprivation therapy was correlated with the serum levels of testosterone (p = 0.002), dehydroepiandrosterone sulfate (p = 0.002), androstenedione (p = 0.006) and prostate specific antigen (p <0.001). Serum dehydroepiandrosterone sulfate and androstenedione levels were also correlated with serum prostate specific antigen (p <0.001 and p = 0.002, respectively). CONCLUSIONS: In patients treated with androgen deprivation therapy the pituitary-adrenal axis mediated by adrenocorticotropic hormone has a central role in the regulation of androgen synthesis. Serum adrenocorticotropic hormone and adrenal androgen concentrations were correlated with the posttreatment prostate specific antigen. Adrenocorticotropic hormone mediated androgen synthesis is a potential target for advanced androgen deprivation therapy.

Oncological results, functional outcomes and health-related quality-of-life in men who received a radical prostatectomy or external beam radiation therapy for localized prostate cancer: a study on long-term patient outcome with risk stratification.

Health-related quality-of-life (HRQOL) after a radical prostatectomy (RP) or external beam radiation therapy (EBRT) has not been studied in conjunction with oncological outcomes in relation to disease risk stratification. Moreover, the long-term outcomes of these treatment approaches have not been studied. We retrospectively analyzed oncological outcomes between consecutive patients receiving RP (n=86) and EBRT (n=76) for localized prostate cancer. HRQOL and functional outcomes could be assessed in 62 RP (79%) and 54 EBRT (79%) patients over a 3-year follow-up period (median: 41 months) using the Medical Outcomes Study Short Form-36 (SF-36) and the University of California Los Angeles Prostate Cancer Index (UCLA PCI). The 5-year biochemical progression-free survival did not differ between the RP and EBRT groups for low-risk (74.6% vs. 75.0%, P=0.931) and intermediate-risk (61.3% vs. 71.1%, P=0.691) patients. For high-risk patients, progression-free survival was lower in the RP group (45.1%) than in the EBRT group (79.7%) (P=0.002). The general HRQOL was comparable between the two groups. Regarding functional outcomes, the RP group reported lower scores on urinary function and less urinary bother and sexual bother than the EBRT group (P<0.001, P<0.05 and P<0.001, respectively). With risk stratification, the low- and intermediate-risk patients in the RP group reported poorer urinary function than patients in the EBRT group (P<0.001 for each). The sexual function of the high-risk patients in the EBRT group was better than that of the same risk RP patients (P<0.001). Biochemical recurrence was not associated with the UCLA PCI score in either group. In conclusion, low- to intermediate-risk patients treated with an RP may report relatively decreased urinary function during long-term follow-up. The patient's HRQOL after treatment did not depend on biochemical recurrence.

Enzalutamide-induced severe thrombocytopenia complicated by a seizure in a 76-year-old man with castration-resistant prostate cancer.

INTRODUCTION: Adverse events with enzalutamide widely used for men with castration-resistant prostate cancer are of interest. CASE PRESENTATION: A 76-year-old man developed castration-resistant prostate cancer. He received 160 mg of enzalutamide daily. On the 13th day after treatment, severe thrombocytopenia was observed (platelet count: 1.9 × 104/µL). Normal coagulation and fibrinolytic systems suggested thrombocytopenia induced by enzalutamide. Enzalutamide was withdrawn immediately, and platelet count uneventfully recovered to 7.0 × 104/µL and 28.8 × 104/µL 9 and 30 days after discontinuation, respectively. He restarted enzalutamide therapy without thrombocytopenia recurrence. However, 81 days after restarting enzalutamide, he experienced a seizure. There were no significant findings from brain computed tomography, which suggested that the seizure was also an enzalutamide-associated adverse event. CONCLUSION: Thrombocytopenia may occur early following enzalutamide therapy, and blood analysis within 2 weeks after treatment may facilitate its management. Enzalutamide-induced thrombocytopenia, complicated by seizure, has not been reported.

Primary solitary fibrous tumor (SFT) in the retroperitoneum.

BACKGROUND: Solitary fibrous tumor (SFT) is an infrequent but distinct neoplasm, which generally arises from submesothelial connective tissue in the pleura. SFT is rarely recognized in extrathoracic sites, and histologically identical conditions have also been reported in the retroperitoneum, although their pathophysiology has not been extensively investigated. METHODS: We present four cases of primary SFT in the retroperitoneum, and review 37 similar cases in the previous literature. RESULTS: About 40% of patients were asymptomatic, and 19.2% and 15.4% presented with an abdominal mass and urinary symptoms, respectively. The tumor size ranged between 2 and 26 (mean 9.1) cm. Sixty-three percent of tumors showed nonspecific development with haphazard distribution of bland short spindle or polygonal cells with or without collagenous bundles and stromal hyalinization. In 22.0%, hemangiopericytomatous appearance was seen. About 15% of cases showed histologically malignant characteristics. The tumor cells were immunoreactive for vimentin in all cases, CD34 in 91% and Bcl-2 in 86%. All tumors were excised, and in 85.4% of cases, tumors did not recur postoperatively for 6 to 48 months. No significant difference was found between the recurrence rate of histologically benign and malignant cases. Cases positive for both CD34 and Bcl-2 had no recurrence. CONCLUSIONS: The identification of SFT in the retroperitoneum is of importance because histopathological indicators of malignancy are not necessarily associated with clinical malignant potential in many cases of retroperitoneal SFT. Retroperitoneal SFT showing typical pathological features with expression of CD34 and Bcl-2 is associated with a favorable outcome following excision.

[LEIOMYOSARCOMA OF THE OVARIAN VEIN WITH THE RENAL VEIN INVASION: A CASE REPORT].

A 56-year-old woman had complained of two year's consecutive left-side abdominal pain. Retroperitoneal tumor was diagnosed and the patient was referred to our institute in December 2014. Laboratory data including endocrinological activity and serological markers were within the normal ranges. Imaging studies showed that the solid tumor measuring 5 cm in diameter was uncovered in the retroperitoneum, between the abdominal aorta and left kidney. The patient underwent surgical removal of the tumor with the left kidney because the mass was highly adhesive to the left ovarian vessels and left renal vein. Histological examination showed proliferating spindle cells in the tumor, and immunoreactivity for desmin and alfa-smooth muscle actin in tumor cells confirmed the diagnosis of leiomyosarcoma originated in left ovarian vein with left renal vein invasion. The patient has been free of disease 21 months after the surgery. Ovarian vein leiomyosarcoma is extremely rare and we have found 18 cases in literature. Furthermore, only three cases of leiomyosarcoma arising from the ovarian vein with the renal vein invasion were reported including our case.

Dihydrotestosterone synthesis pathways from inactive androgen 5α-androstane-3ß,17ß-diol in prostate cancer cells: Inhibition of intratumoural 3ß-hydroxysteroid dehydrogenase activities by abiraterone.

Intratumoural dihydrotestosterone (DHT) synthesis could be an explanation for castration resistance in prostate cancer (PC). By using liquid chromatography-mass spectrometry, we evaluated the intratumoral DHT synthesis from 5α-androstane-3ß,17ß-diol (3ß-diol), which is inactive androgen metabolized from DHT. 3ß-diol had biochemical potential to be converted to DHT via three metabolic pathways and could stimulate PC cell growth. Especially, 3ß-diol was not only converted back to upstream androgens such as dehydroepiandrosterone (DHEA) or Δ5-androstenediol but also converted directly to DHT which is the main pathway from 3ß-diol to DHT. Abiraterone had a significant influence on the metabolism of DHEA, epiandrosterone and 3ß-diol, by the inhibition of the intratumoural 3ß-hydroxysteroid dehydrogenase (3ß-HSD) activities which is one of key catalysts in androgen metabolic pathway. The direct-conversion of 3ß-diol to DHT was catalysed by 3ß-HSD and abiraterone could inhibit this activity of 3ß-HSD. These results suggest that PC had a mechanism of intratumoural androgen metabolism to return inactive androgen to active androgen and intratumoural DHT synthesis from 3ß-diol is important as one of the mechanisms of castration resistance in PC. Additionally, the inhibition of intratumoural 3ß-HSD activity could be a new approach to castration-resistant prostate cancer treatment.

Estrogen receptor alpha drives proliferation in PTEN-deficient prostate carcinoma by stimulating survival signaling, MYC expression and altering glucose sensitivity.

While high doses of estrogen, in combination with androgens, can initiate prostate cancer (PCa) via activation of the estrogen receptor α (ERα), the role of ERα in PCa cells within established tumors is largely unknown. Here we show that expression of ERα is increased in high grade human PCa. Similarly, ERα is elevated in mouse models of aggressive PCa driven by MYC overexpression or deletion of PTEN. Within the prostate of PTEN-deficient mice, there is a progressive pattern of ERα expression: low in benign glands, moderate in tumors within the dorsal, lateral and ventral lobes, and high in tumors within the anterior prostate. This expression significantly correlates with the proliferation marker Ki67. Furthermore, in vitro knockdown of ERα in cells derived from PTEN-deficient tumors causes a significant and sustained decrease in proliferation. Depletion of ERα also reduces the activity of the PI3K and MAPK pathways, both downstream targets of non-genomic ERα action. Finally, ERα knockdown reduces the levels of the MYC protein and lowers the sensitivity of cellular proliferation to glucose withdrawal, which correlates with decreased expression of the glucose transporter GLUT1. Collectively, these results demonstrate that ERα orchestrates proliferation and metabolism to promote the neoplastic growth of PCa cells.

Limited significance of repeated long-term radiological and hormonal examination in nonfunctioning adrenal incidentalomas

ABSTRACT Purpose: The purposes of the present study were to evaluate growth rate of nonfunctioning adrenal incidentalomas (AIs) and their development to hormonal hypersecretion on follow-up. Materials and methods: A retrospective study was conducted from the electronic medical records. A total of 314 patients were diagnosed with adrenal tumors between 2000 and 2016. After excluding patients who had overt adrenal endocrine disorders or whose adrenal tumors were clinically diagnosed as metastatic malignancies, we investigated 108 patients with nonfunctioning AIs including characteristics, the treatment, the way of follow-up and pathology. Results: Fifteen patients received immediate adrenalectomy because of the initial tumor size or patient's preference. Pathological examination revealed malignancy in 2 patients. In the remaining 93 patients, radiological examinations were performed periodically. Tumor enlargement of ≥ 1.0cm was observed in 8.6% of the patients who were followed up as nonfunctioning AIs with a median follow-up period of 61.5 months (range: 4-192). Eleven patients underwent adrenalectomy. On the pathological examinations, all of the tumors, which showed a size increase, were diagnosed as benign tumors. Regarding the followed up patients without adrenalectomy, only 2.4% of the patients had tumor enlargement during the prolonged follow-up. Furthermore, none of the patients developed hormonal hypersecretion or clinical signs such as obesity, glucose intolerance or poorly controlled hypertension. Conclusions: Tumor enlargement of AIs did not correlate with malignancy. The value of repeat radiological and hormonal examinations may be limited in the long-term follow-up of patients whose AIs are not enlarged.

Androgen deprivation promotes intratumoral synthesis of dihydrotestosterone from androgen metabolites in prostate cancer.

Intratumoral synthesis of dihydrotestosterone (DHT) from precursors cannot completely explain the castration resistance of prostate cancer. We showed that DHT was intratumorally synthesized from the inactive androgen metabolites 5α-androstane-3α/ß,17ß-diol (3α/ß-diol) in prostate cancer cells via different pathways in a concentration-dependent manner. Additionally, long-term culture in androgen-deprived media increased transcriptomic expression of 17ß-hydroxysteroid dehydrogenase type 6 (HSD17B6), a key enzyme of oxidative 3α-HSD that catalyzes the conversion of 3α-diol to DHT in prostate cancer cells. Correspondingly, the score for HSD17B6 in tissues of 42 prostate cancer patients undergoing androgen deprivation therapy (ADT) was about 2-fold higher than that in tissues of 100 untreated individuals. In men receiving ADT, patients showing biochemical progression had a higher HSD17B6 score than those without progression. These results suggested that 3α/ß-diol also represent potential precursors of DHT, and the back conversion of DHT from androgen derivatives can be a promising target for combination hormone therapy.

Insulin-like growth factor-1 is associated with regulation of the luteinizing hormone production in men receiving androgen deprivation therapy with gonadotropin-releasing hormone analogues for localized prostate cancer.

BACKGROUND: Luteinizing hormone (LH) during androgen-deprivation therapy (ADT) with gonadotropin-releasing hormone analogues (GnRHa) has been thought to be biologically inactive, and the regulation of LH during ADT with GnRHa is thus unknown. Insulin-like growth factor-1 (IGF-1) is involved in the regulation of cell proliferation and differentiation, and IGF-1 production in the liver is dependent on growth hormone (GH) secretion from the anterior pituitary. Despite the presence of IGF-1 receptors in the gonadotroph, associations between the GH/IGF-1 and pituitary-gonadal axes, e.g., whether IGF-1 elicits the LH secretion, remain unclear. METHODS: Seventy-one patients with localized prostate cancer, who received ADT with GnRHa, were prospectively studied based on their blood samples before treatment and after ADT for 6 months. We employed highly sensitive assays for measurement of serum testosterone (electrochemiluminescence immunoassay), GH/IGF-1 (radioimmunoassay), adrenocorticotropic hormone (ACTH: immunoradiometric assay), LH (chemiluminescent immunoassay), and dehydroepiandrosterone sulfate (DHEA-S: chemiluminescent enzyme immunoassay). RESULTS: No correlation was noted between the pretreatment LH and IGF-1 levels; after ADT, the serum LH level was closely correlated with the IGF-1 concentration [Spearman's correlation coefficient (rs) = 0.370, P = 0.001]. The serum levels of androgens and gonadotropins reduced following ADT (P < 0.001 in all). The serum IGF-1 level increased (22 ± 6 nmol/L) compared with that at the baseline (19 ± 5 nmol/L) (P < 0.001), but no change was observed in the serum GH concentration between before and after ADT (1.4 ± 2.3 vs. 0.9 ± 0.9 µg/L, respectively, P = 0.691). The serum testosterone level was not correlated with the LH level either before or after ADT. The testosterone and DHEA-S levels after ADT were correlated with ACTH concentration (rs = 0.367, P = 0.002 and rs = 0.354, P = 0.002, respectively). We did not identify any correlations between the serum IGF-1 concentration and Gleason score, PSA value, or androgen levels. CONCLUSIONS: During ADT with GnRHa, IGF-1 possibly promotes LH production, although its role is unclear. Associations among pituitary-gonadal, pituitary-adrenal, and GH/IGF-1 axes represented by IGF-1-mediated LH secretion and ACTH-mediated androgen synthesis are of interest, since both prostate epithelium proliferation and male anabolic activity are involved in these 3 axes. Assessment of oncologic outcomes is warranted for their significance in patients with prostate cancer.

Deficiency in androgens and upregulation of insulin-like growth factor-1 are involved in high bone turnover in men receiving androgen deprivation therapy for prostate cancer.

OBJECTIVE: This study was performed to elucidate the mechanism of high bone turnover during androgen deprivation therapy (ADT) in terms of osteogenic endocrine activity by testosterone, adrenal androgens, and insulin-like growth factor-1 (IGF-I), and to identify markers reflecting the bone mineral density (BMD) during ADT. DESIGN: BMD and samples of blood and urine were studied before and after 6months of ADT in 70 patients with localized prostate cancer. RESULTS: Before ADT, serum free-testosterone, dehydroepiandrosterone sulfate (DHEA-S), androstenedione, and IGF-I levels were correlated with BMD (rs=0.344, p=0.004; rs=0.264, p=0.027; rs=0.329, p=0.005; rs=0.300, p=0.012, respectively). The serum IGF-I level was independently correlated with the pretreatment BMD (Multivariate p=0.001). These relationships disappeared after ADT (p=0.519, 0.316, 0.116, and 0.597, respectively). After ADT, serum levels of free-testosterone decreased (7.9 to 0.2pg/mL), and DHEA-S and androstenedione were also reduced (3.6 to 2.3µmol/L and 5.6 to 2.9nmol/L, respectively) (p<0.001 in all). In contrast, IGF-I levels were elevated after ADT by 11.6% (19.9 to 22.3nmol/L, p<0.001). Delta-values of IGF-I (post- minus pretreatment levels, mean: +2.2, ranged between -7.1 and +15.3) were inversely correlated with the pretreatment (rs=-0.333 p=0.005) and post-treatment (rs=-0.408, p=0.001) BMD. After ADT, the serum IGF-I level was closely correlated with the serum level of the bone formation marker bone-specific alkaline phosphatase (BAP) (rs=0.328, p=0.006), and delta-IGF-I and delta-BAP showed a close positive correlation (rs=0.388, p=0.001). The post-treatment BMD was correlated only with the urine deoxypyridinoline (DPD) concentration (rs=-0.302, p=0.024) among the bone formation/resorption markers including serum/urine N-telopeptide. CONCLUSIONS: Serum IGF-I levels increased during ADT in men with a low BMD. Coupled with reduced androgen levels, elevated IGF-I levels, which were positively correlated with BAP during ADT, possibly explain the mechanism of ADT-related high bone turnover. The increase of IGF-I is more prominent in men whose BMD is already low at the baseline, and urine DPD might be a marker that reflects BMD during ADT.