Serum testosterone plays an important role in the metastatic ability of castration resistant prostate cancer

Influence of fetal Leydig cells on the development of adult Leydig cell population in rats

Leydig cells are the main endogenous testosterone synthesis cells in the body. Testosterone is an essential hormone in males that affects metabolism, emotion, and pubertal development. However, little is known about the development of Leydig cells and relationship between fetal Leydig cells (FLCs) and adult Leydig cells (ALCs). The aims of this study were to investigate the effect of (FLCs) on ALC development. Our study showed that FLCs in neonatal rat testis can be eliminated by 100 mg/kg ethane dimethane sulfonate (EDS) treatment without affecting the health of newborn rats. Immunohistological results showed that eliminating FLCs led to early re-generation of the ALC population (progenitor Leydig cells [PLCs] and ALCs) accompanied at first by increased and then by decreased serum testosterone, indicating that ALCs which appeared after neonatal EDS treatment were degenerated or had attenuated functions. Our results showed that FLCs were eliminated 4 days after EDS treatment, the ALC population regenerated by 21 days, and serum testosterone levels dramatically decreased at 56 days. Collectively, our results indicate that the ablation of FLCs in neonatal rat results in abnormal development of ALCs. Our study further indicates that abnormal development of Leydig cells in the fetal stage leads to steroid hormone disorders, such as testosterone deficiency, in the adult stage. Therefore, studies of Leydig cell development are important for understanding the pathogenesis of testosterone deficiency or pubertas praecox.

Reporting and ideal testosterone levels in men undergoing androgen deprivation for prostate cancer-time for a rethink?

BACKGROUND

This study aims to review current laboratory reporting strategies across Australia and New Zealand with a view to propose a more useful template for reporting serum testosterone in the context of prostate cancer.

MATERIALS AND METHODS

Registered pathology laboratories in Australia and New Zealand were enrolled into the current study. An electronic or a phone survey was utilized to collect data from each participating laboratory. Obtained information included assay utilized, units reported, reference intervals, lowest reported value, and lowest detectable value. To identify recommendations for testosterone testing, a systematic search was performed across Web of Science (including MEDLINE), EMBASE, and Cochrane libraries.

RESULTS

Assessment of national pathology laboratories identified significant heterogeneity in the reporting methods. Reports typically used a "normal healthy male of 35 years of age" as a comparator but did not refer to optimal castrate levels, the lowest level that their assay was able to detect, nor did they include appended clinical guidelines relating to the prostate cancer patient cohort.

CONCLUSIONS

Across Australia and New Zealand, various methods for testing and reporting serum testosterone exist, while international guidelines remain vague. The fashion in which serum testosterone levels are displayed should be re-evaluated to address the relevant clinical population and reflect an agreed-upon castrate threshold in patients undergoing androgen deprivation therapy.

Antagonizing effects of membrane-acting androgens on the eicosanoid receptor OXER1 in prostate cancer

Accumulating evidence during the last decades revealed that androgen can exert membrane initiated actions that involve signaling via specific kinases and the modulation of significant cellular processes, important for prostate cancer cell growth and metastasis. Results of the present work clearly show that androgens can specifically act at the membrane level via the GPCR oxoeicosanoid receptor 1 (OXER1) in prostate cancer cells. In fact, OXER1 expression parallels that of membrane androgen binding in prostate cancer cell lines and tumor specimens, while in silico docking simulation of OXER1 showed that testosterone could bind to OXER1 within the same grove as 5-OxoETE, the natural ligand of OXER1. Interestingly, testosterone antagonizes the effects of 5-oxoETE on specific signaling pathways and rapid effects such as actin cytoskeleton reorganization that ultimately can modulate cell migration and metastasis. These findings verify that membrane-acting androgens exert specific effects through an antagonistic interaction with OXER1. Additionally, this interaction between androgen and OXER1, which is an arachidonic acid metabolite receptor expressed in prostate cancer, provides a novel link between steroid and lipid actions and renders OXER1 as new player in the disease. These findings should be taken into account in the design of novel therapeutic approaches in prostate cancer.

Testosterone therapy and prostate cancer--safety concerns are well founded

Testosterone is a potent hormone with a variety of physiological effects. The diagnosis of androgen deficiency has increased dramatically over the past decade, along with the widespread use of testosterone supplementation therapy (TST). The long-term effects of TST are uncertain, and the risk of overdiagnosis and overtreatment of men who have a normal age-related decline in testosterone is substantial. The biology of the androgen receptor (AR) pathway is complex, and the saturation model does not take the heterogeneity of human prostate cancer into account. Large-scale trials to confirm the safety of testosterone with respect to the risks of prostate cancer and cardiovascular disease with reasonable confidence limits have not been done, and existing data are insufficient to exclude these adverse events. Instead, evidence suggests that prostate cancer could, in fact, be stimulated by TST, and that the risk of cardiovascular events is increased. Overall, TST seems to impose significant risks, and should be used with caution.

A comparison of the biological features of prostate cancer with (PSA+, PSMA+) profile according to RKIP

PURPOSE

To investigate differences in the biological features of the most immunoexpressed prostate cancer (PC) profiles (PSA+, PSMA+) according to the RKIP.

METHODS

19 PC with dominant Gleason grade ≥ 8 were studied. Expression of PSA, PSMA, RKIP, Raf-1, MEK-1, ERK-1, ERK-2, p-Akt (T308), p-Akt (S473), NF- κ B p50, and NF- κ Bp65 were detected immunohistochemically.

RESULTS

. Loss of RKIP in the most immunoexpressed PC (PSA+, PSMA+) profile was associated with increased levels of PSA and PSMA expression. Intensities of immunoreactions to PSA and PSMA were higher in cancer cells negative for RKIP (12.51 ± 1.6 and 34.95 ± 1.92) compared to those positive for RKIP (4.68 ± 1.11 and 28.56 ± 0.91). In parallel, missing RKIP expression in PC patients with PSA+, PSMA+ profile was connected with increased components of both Raf-1/MEK/ERK and NF- κ B (p65/p50), whereas Akt is activated independently of RKIP.

CONCLUSIONS

Although characterized by the same (PSA+, PSMA+) profile, PC phenotype missing the RKIP related to invasive potential and greater biological aggressiveness reflected in overexpression of components of Raf-1/MEK/ERK and NF- κ B (p65/p50) in which Akt is activated independently of RKIP. Taking into account the PC phenotypes according to RKIP among PSA-PSMA profiles may improve distinguishing them from cancers that will become more aggressive and therefore adapt the therapeutic strategies in those patients.