- Association between duration and type of Androgen Deprivation Therapy and risk of diabetes in men with prostate cancer. [JOURNAL ARTICLE]
- Int J Cancer 2016 Aug 25.
Androgen deprivation therapy (ADT) for prostate cancer (PCa) increases risk of type 2 diabetes (T2DM); however the association between types and duration of ADT has not been fully elucidated. We examined how type and duration of ADT affects risk of T2DM. Using data from Prostate Cancer database Sweden (PCBaSe) we investigated risk of T2DM in a cohort of 34,031 men with PCa on ADT; i.e. anti-androgens (AA), orchiectomy, or gonadotropin-releasing hormone (GnRH) agonists compared to an age-matched, PCa-free comparison cohort (n=167,205) using multivariate Cox proportional hazard regression. T2DM was defined as a newly filled prescription for metformin, sulphonylurea or insulin in the Prescribed Drug Register. A total of 21,874 men with PCa received GnRH agonists, 9,143 AA and 3,014 underwent orchiectomy. Risk of T2DM was increased in men in the GnRH agonists/orchiectomy group during the first 3 years of ADT [i.e.1-1.5 years HR: 1.61 (95%CI: 1.36-1.91)], compared to PCa-free men. The risk decreased thereafter (e.g 3-4 years HR: 1.17 (95% CI: 0.98-1.40)). Conversely, no increased risk was seen in men on AA (HR: 0.74 (95%CI: 0.65-0.84). The incidence of T2DM per 1,000 person-years was 10 for PCa-free men, 8 for men on AA, and 13 for men on GnRH agonists/orchiectomy. Duration of ADT has a significant impact on risk of T2DM. With the peak after three years of treatment, our data indicates that men on ADT, even for a limited period of time, such as adjuvant to radiotherapy, are at increased risk of T2DM. This article is protected by copyright. All rights reserved.
- The Impact of Obesity on Patient Reported Outcomes Following Stereotactic Body Radiation Therapy for Prostate Cancer. [Journal Article]
- Cureus 2016; 8(7):e669.
The relationship between obesity (Body Mass Index ->30 kg/m(2)) and quality of life (QoL) following prostate cancer (PCa) radiation therapy (RT) is unknown. Excess abdominal fat may compromise the precise delivery of radiation, putting surrounding organs at risk for greater radiation exposure. Stereotactic body radiation therapy (SBRT) utilizes a real-time tracking system that provides updated prostate position information and allows for correction of the therapeutic beam during treatment with high accuracy. In this study, we evaluate the impact of obesity on patient reported outcomes following SBRT for prostate cancer.Between February 2008 and April 2012, 88 obese and 178 non-obese patients with PCa were treated with SBRT at Georgetown University Hospital, Washington, DC. Health-related quality of life (HRQol) was assessed via the expanded prostate cancer index composite (EPIC)-26 at baseline, 6, 12, 18, and 24 months after 5-fraction delivery of 35-36.25 Gy with the CyberKnife. Patients who received androgen deprivation therapy (ADT) were excluded from this analysis due to its known negative impact on HRQoL.Pretreatment characteristics of obese and non-obese patient groups were similar except that obese patients had lower total testosterone levels. Urinary and bowel function and bother scores between the two patient cohorts were comparable at baseline and subsequent follow-ups. Sexual function and bother were also similar at baseline between both groups. Bother was defined by displeasure patients may experience from functional decline. At 24 months post-SBRT, obese men experienced borderline clinically significant decrease in sexual function and greater sexual bother compared to non-obese patients. Fatigue was significantly higher in obese patients compared to non-obese patients at 18 months post-SBRT.Prostate SBRT affects obese and non-obese patients similarly in total HRQoL scores and majority of its domains. Obesity has been associated with cancer recurrence; therefore longer follow-up is required to determine the impact of obesity on cancer control.
- Evidence-based recommendations on androgen deprivation therapy for localized and advanced prostate cancer. [Journal Article, Review]
- Cent European J Urol 2016; 69(2):131-8.
The management of prostate cancer (PC) is still evolving. Although, androgen deprivation therapy (ADT) is an established treatment option, particularly in patients with disseminated disease, important data regarding hormonal manipulation have recently emerged. The aim of this paper is to review the evidence on ADT, make recommendations and address areas of controversy associated with its use in men with PC.An expert panel was convened. Areas related to the hormonal management of patients with PC requiring evidence review were identified and questions to be addressed by the panel were determined. Appropriate literature review was performed and included a search of online databases, bibliographic reviews and consultation with experts.The panel was able to provide recommendations on: 1) which patients with localised PC should receive androgen deprivation in conjunction with radiotherapy (RT); 2) what standard initial treatment should be used in metastatic hormone-naïve PC (MHNPC); 3) efficacy of androgen deprivation agents; 4) whether ADT should be continued in patients with castration resistant PC (CRPC). However, no recommendations could be made for combined ADT and very high-dose RT in patients with an intermediate-risk disease.ADT remains the cornerstone of treatment for both metastatic hormone-naïve and castration-resistant PC. According to the expert panel's opinion, based on the ERG report, luteinizing hormone-releasing hormone agonists might not be equivalent but this needs to be confirmed in long-term data. The combined use of ADT and RT improves outcome and survival in men with high-risk localised disease. The benefits in patients with intermediate-risk disease, particularly those subject to escalated dose RT are controversial.
- Transcript Levels of Androgen Receptor Variant 7 and Ubiquitin-Conjugating Enzyme 2C in Hormone Sensitive Prostate Cancer and Castration-Resistant Prostate Cancer. [JOURNAL ARTICLE]
- Prostate 2016 Aug 22.
This study is designed to identify the androgen receptor variant 7 (AR-V7) status, clinical significance of AR-V7 in hormone sensitive prostate cancer (HSPC). Then, we evaluated AR-V7 and changes of its target gene, ubiquitin-conjugating enzyme E2C (UBE2C) which is an anaphase-promoting complex/cyclosome (APC/C)-specific ubiquitin-conjugating enzyme, in castration-resistant prostate cancer (CRPC) in serial tumor biopsies from patients receiving androgen deprivation therapy.We used RT-PCR and Q-PCR assay to evaluate AR-V7, androgen receptor full length (AR-FL), and UBE2C in tumor biopsies from patients with HSPC and CRPC. We examined associations between mRNA expression of AR-V7 and clinicopathologic factors. Furthermore, to identify other potential genes involved in the development of CRPC, RNA sequencing was conducted, using paired prostate cancer (PCa) tissues obtained immediately prior to treatment and at the time of therapeutic resistance.A total of 13 HSPC patients and three CRPC patients were enrolled. Neither a high Gleason score (score of 8 and 9) nor a high risk of PCa (a high risk of locally advanced PCa according to NCCN guidelines) was correlated with mRNA expression of AR-V7 in HSPC (P = 0.153 and P = 0.215). The mRNA expression of AR-FL, but not AR-V7, was significantly associated with the mRNA expression of UBE2C level in HSPC (P = 0.007). However, increased expression of AR-V7, not AR-FL, paralleled increased expression of UBE2C in the CRPC specimens (P = 0.03). AR-V7 expression status before ADT was likely related to shorter CRPC development in patients treating ADT. The result of the RNA-sequencing analysis using serial samples from the same patient before and after castration demonstrated an increased level of the PI3K regulatory subunit 1 (P = 0.018).Our study revealed the role of UBE2C as a marker of the androgen signaling pathway in PCa. Differential gene expression analysis using serial samples from the same patient before and after castration revealed potential genes and pathways involved in development of CRPC. Further studies are needed to determine whether these genes and pathways are potential therapeutic target for CRPC. Prostate © 2016 Wiley Periodicals, Inc.
- Characterization of a monocyanide model of FeFe hydrogenases - highlighting the importance of the bridgehead nitrogen for catalysis. [JOURNAL ARTICLE]
- Dalton Trans 2016 Aug 23.
An azadithiolate bridged monocyanide derivative [Fe2(adt)(CO)5(CN)](-) of [Fe2(adt)(CO)4(CN)2](2-) has been prepared and extensively characterized as a model of the [FeFe]-hydrogenase active site, using a combination of FTIR spectroscopy, electrochemical methods and catalytic assays with chemical reductants. The presence of two basic nitrogen sites opens up multiple protonation pathways, enabling catalytic proton reduction. To our knowledge [Fe2(adt)(CO)5(CN)](-) represents the first example of a cyanide containing [FeFe]-hydrogenase active site mimic capable of catalytic H2 formation in aqueous media.
- Oligometastatic prostate cancer: Metastases-directed therapy? [Journal Article, Review]
- Arab J Urol 2016 Sep; 14(3):179-82.
Since the introduction of anatomical and functional imaging with multiparametric magnetic resonance imaging and choline or prostate-specific membrane antigen positron emission tomography-computed tomography, we are able to diagnose a previously unknown disease, the oligometastatic prostate cancer after local therapy. Reports on surgical and radiation treatment for low-volume metastatic recurrence have shown promising results, with definitive cure in few but a relevant delay of androgen-deprivation therapy with both treatment methods. Obviously, these results need to be validated with prospective randomised data.
- Activation of GRP/GRP-R signaling contributes to castration-resistant prostate cancer progression. [JOURNAL ARTICLE]
- Oncotarget 2016 Aug 17.
Numerous studies indicate that androgen receptor splice variants (ARVs) play a critical role in the development of castration-resistant prostate cancer (CRPC), including the resistance to the new generation of inhibitors of androgen receptor (AR) action. Previously, we demonstrated that activation of NF-κB signaling increases ARVs expression in prostate cancer (PC) cells, thereby promoting progression to CRPC. However, it is unclear how NF-κB signaling is activated in CRPC. In this study, we report that long-term treatment with anti-androgens increases a neuroendocrine (NE) hormone - gastrin-releasing peptide (GRP) and its receptor (GRP-R) expression in PC cells. In addition, activation of GRP/GRP-R signaling increases ARVs expression through activating NF-κB signaling. This results in an androgen-dependent tumor progressing to a castrate resistant tumor. The knock-down of AR-V7 restores sensitivity to antiandrogens of PC cells over-expressing the GRP/GRP-R signaling pathway. These findings strongly indicate that the axis of Androgen-Deprivation Therapy (ADT) induces GRP/GRP-R activity, activation NF-κB and increased levels of AR-V7 expression resulting in progression to CRPC. Both prostate adenocarcinoma and small cell NE prostate cancer express GRP-R. Since the GRP-R is clinically targetable by analogue-based approach, this provides a novel therapeutic approach to treat advanced CRPC.
- Perpetuating effects of androgen deficiency on insulin-resistance. [JOURNAL ARTICLE]
- Int J Obes (Lond) 2016 Aug 18.
Androgen deprivation therapy (ADT) is commonly used for treatment of prostate cancer, but is associated with side effects such as sarcopenia and insulin resistance. The role of lifestyle factors such as diet and exercise on insulin sensitivity and body composition in testosterone-deficient males is poorly understood. The aim of the present study was to examine the relationships between androgen status, diet, and insulin sensitivity.Middle-aged (11-12-yo) intact and orchidectomized male rhesus macaques were maintained for two months on a standard chow diet, and then exposed for six months to a Western-style, high-fat/calorie-dense diet (WSD) followed by four months of caloric restriction (CR). Body composition, insulin sensitivity, physical activity, serum cytokine levels, and adipose biopsies were evaluated before and after each dietary intervention.Both intact and orchidectomized animals gained similar proportions of body fat, developed visceral and subcutaneous adipocyte hypertrophy, and became insulin resistant in response to the WSD. CR reduced body fat in both groups, but reversed insulin resistance only in intact animals. Orchidectomized animals displayed progressive sarcopenia, which persisted after the switch to CR. Androgen deficiency was associated with increased levels of interleukin-6 and macrophage-derived chemokine (CCL22), both of which were elevated during CR. Physical activity levels showed a negative correlation with body fat and insulin sensitivity.Androgen deficiency exacerbated the negative metabolic side effects of the WSD, such that CR alone was not sufficient to improve altered insulin sensitivity, suggesting that ADT patients will require additional interventions to reverse insulin resistance and sarcopenia.International Journal of Obesity accepted article preview online, 18 August 2016. doi:10.1038/ijo.2016.148.
- Long-term decision regret after post-prostatectomy image-guided intensity-modulated radiotherapy. [JOURNAL ARTICLE]
- J Med Imaging Radiat Oncol 2016 Aug 16.
Decision regret (DR) may occur when a patient believes their outcome would have been better if they had decided differently about their management. Although some studies investigate DR after treatment for localised prostate cancer, none report DR in patients undergoing surgery and post-prostatectomy radiotherapy. We evaluated DR in this group of patients overall, and for specific components of therapy.We surveyed 83 patients, with minimum 5 years follow-up, treated with radical prostatectomy (RP) and post-prostatectomy image-guided intensity-modulated radiotherapy (IG-IMRT) to 64-66 Gy following www.EviQ.org.au protocols. A validated questionnaire identified DR if men either indicated that they would have been better off had they chosen another treatment, or they wished they could change their mind about treatment.There was an 85.5% response rate, with median follow-up post-IMRT 78 months. Adjuvant IG-IMRT was used in 28% of patients, salvage in 72% and ADT in 48%. A total of 70% of patients remained disease-free. Overall, 16.9% of patients expressed DR for treatment, with fourfold more regret for the RP component of treatment compared to radiotherapy (16.9% vs 4.2%, P = 0.01). DR for androgen deprivation was 14.3%. Patients were regretful of surgery due to toxicity, not being adequately informed about radiotherapy as an alternative, positive margins and surgery costs (83%, 33%, 25% and 8% of regretful patients respectively). Toxicity caused DR in the three radiotherapy-regretful and four ADT-regretful patients. Patients were twice as regretful overall, and of surgery, for salvage vs adjuvant approaches (both 19.6% vs 10.0%).Decision regret after RP and post-prostatectomy IG-IMRT is uncommon, although patients regret RP more than post-operative IG-IMRT. This should reassure urologists referring patients for post-prostatectomy IG-IMRT, particularly in the immediate adjuvant setting. Other implications include appropriate patient selection for RP (and obtaining clear margins), and ensuring adequately discussing definitive radiotherapy as an alternative to surgery.
- Contemporary Update of a Multi-Institutional Predictive Nomogram for Salvage Radiotherapy After Radical Prostatectomy. [JOURNAL ARTICLE]
- J Clin Oncol 2016 Aug 15.
We aimed to update a previously published, multi-institutional nomogram of outcomes for salvage radiotherapy (SRT) following radical prostatectomy (RP) for prostate cancer, including patients treated in the contemporary era.Individual data from node-negative patients with a detectable post-RP prostate-specific antigen (PSA) treated with SRT with or without concurrent androgen-deprivation therapy (ADT) were obtained from 10 academic institutions. Freedom from biochemical failure (FFBF) and distant metastases (DM) rates were estimated, and predictive nomograms were generated.Overall, 2,460 patients with a median follow-up of 5 years were included; 599 patients (24%) had a Gleason score (GS) ≤ 6, 1,387 (56%) had a GS of 7, 244 (10%) had a GS of 8, and 230 (9%) had a GS of 9 to 10. There were 1,370 patients (56%) with extraprostatic extension (EPE), 452 (18%) with seminal vesicle invasion (SVI), 1,434 (58%) with positive surgical margins, and 390 (16%) who received ADT (median, 6 months). The median pre-SRT PSA was 0.5 ng/mL (interquartile range, 0.3 to 1.1). The 5-yr FFBF rate was 56% overall, 71% for those with a pre-SRT PSA level of 0.01 to 0.2 ng/mL (n = 441), 63% for those with a PSA of 0.21 to 0.50 ng/mL (n = 822), 54% for those with a PSA of 0.51 to 1.0 ng/mL (n = 533), 43% for those with a PSA of 1.01 to 2.0 ng/mL (n = 341), and 37% for those with a PSA > 2.0 ng/mL (n = 323); P < .001. On multivariable analysis, pre-SRT PSA, GS, EPE, SVI, surgical margins, ADT use, and SRT dose were associated with FFBF. Pre-SRT PSA, GS, SVI, surgical margins, and ADT use were associated with DM, whereas EPE and SRT dose were not. The nomogram concordance indices were 0.68 (FFBF) and 0.74 (DM).Early SRT at low PSA levels after RP is associated with improved FFBF and DM rates. Contemporary nomograms can estimate individual patient outcomes after SRT in the modern era.