48 research outputs found
Gonadal suppression alters axillary steroid secretions in men, but does that affect olfactory social signaling?
Background and objective: Luteinizing hormone-releasing hormone agonists (LHRHa) suppress gonadal hormone production and are commonly used to treat prostate cancer (PC) in men and conditions ranging from uterine fibroids to estrogen-sensitive cancers in women. They are also used to delay sexual development in children considering gender reassignment or experiencing premature puberty. As chemically castrating agents, LHRHa may affect cutaneous steroid secretions, which, in turn, could alter body odor and influence the psycho-sexual dynamics between individuals. The objectives of the present study were to determine (1) if LHRHa indeed alter cutaneous skin secretions, and (2) whether this leads to perceivable changes in body odor. Material and methods: Axillary skin secretions were collected on new cotton T-shirts worn by men undergoing androgen deprivation therapy with an LHRHa to treat PC (n = 10), both before starting the LHRHa and 3 months later. Healthy heterosexual university students (50 males, 50 females) were recruited to smell and rate the shirts for their masculinity, attractiveness, and intensity of odor. Liquid chromatography-mass spectrometry (LC-MS) was also used to analyze steroids extracted from the shirt samples. Results: LC-MS showed a statistically significant decline in the concentration of the androgenic metabolites, androsterone and 5α-androstane-3,17-dione. This confirms that LHRHa drugs that suppress gonadal hormone production markedly reduce cutaneous secretion of androgenic metabolic intermediates in adult males. However, no differences in odor were detected in the ratings of the shirts by male, female, nor male and female raters combined for any of the three variables assessed. Possible reasons why the human sniffers failed to perceive a change in odor are explored. Conclusion: Our data document that LHRHa alter steroid skin secretions in older men, but whether such changes alter the olfactory signals that might influence psychosocial interactions remains unresolved
Dysregulated fibronectin trafficking by Hsp90 inhibition restricts prostate cancer cell invasion
Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/.The molecular chaperone Hsp90 is overexpressed in prostate cancer (PCa) and is responsible for the folding, stabilization and maturation of multiple oncoproteins, which are implicated in PCa progression. Compared to first-in-class Hsp90 inhibitors such as 17-allylamino-demethoxygeldanamycin (17-AAG) that were clinically ineffective, second generation inhibitor AUY922 has greater solubility and efficacy. Here, transcriptomic and proteomic analyses of patient-derived PCa explants identified cytoskeletal organization as highly enriched with AUY922 treatment. Validation in PCa cell lines revealed that AUY922 caused marked alterations to cell morphology, and suppressed cell motility and invasion compared to vehicle or 17-AAG, concomitant with dysregulation of key extracellular matrix proteins such as fibronectin (FN1). Interestingly, while the expression of FN1 was increased by AUY922, FN1 secretion was significantly decreased. This resulted in cytosolic accumulation of FN1 protein within late endosomes, suggesting that AUY922 disrupts vesicular secretory trafficking pathways. Depletion of FN1 by siRNA knockdown markedly reduced the invasive capacity of PCa cells, phenocopying AUY922. These results highlight a novel mechanism of action for AUY922 beyond its established effects on cellular mitosis and survival and, furthermore, identifies extracellular matrix cargo delivery as a potential therapeutic target for the treatment of aggressive PCa
Correction: Epidermal Growth Factor Receptor in Prostate Cancer Derived Exosomes
<p>Correction: Epidermal Growth Factor Receptor in Prostate Cancer Derived Exosomes</p
Steroidogenesis in Peripheral and Transition Zones of Human Prostate Cancer Tissue
The peripheral zone (PZ) and transition zone (TZ) represent about 70% of the human prostate gland with each zone having differential ability to develop prostate cancer. Androgens and their receptor are the primary driving cause of prostate cancer growth and eventually castration-resistant prostate cancer (CRPC). De novo steroidogenesis has been identified as a key mechanism that develops during CRPC. Currently, there is very limited information available on human prostate tissue steroidogenesis. The purpose of the present study was to investigate steroid metabolism in human prostate cancer tissues with comparison between PZ and TZ. Human prostate cancer tumors were procured from the patients who underwent radical prostatectomy without any neoadjuvant therapy. Human prostate homogenates were used to quantify steroid levels intrinsically present in the tissues as well as formed after incubation with 2 µg/mL of 17-hydroxypregnenolone (17-OH-pregnenolone) or progesterone. A Waters Acquity ultraperformance liquid chromatography coupled to a Quattro Premier XE tandem quadrupole mass spectrometer using a C18 column was used to measure thirteen steroids from the classical and backdoor steroidogenesis pathways. The intrinsic prostate tissue steroid levels were similar between PZ and TZ with dehydroepiandrosterone (DHEA), dihydrotestosterone (DHT), pregnenolone and 17-OH-pregnenolone levels higher than the other steroids measured. Interestingly, 5-pregnan-3,20-dione, 5-pregnan-3-ol-20-one, and 5-pregnan-17-ol-3,20-dione formation was significantly higher in both the zones of prostate tissues, whereas, androstenedione, testosterone, DHT, and progesterone levels were significantly lower after 60 min incubation compared to the 0 min control incubations. The incubations with progesterone had a similar outcome with 5-pregnan-3,20-dione and 5-pregnan-3-ol-20-one levels were elevated and the levels of DHT were lower in both PZ and TZ tissues. The net changes in steroid formation after the incubation were more observable with 17-OH-pregnenolone than with progesterone. In our knowledge, this is the first report of comprehensive analyses of intrinsic prostate tissue steroids and precursor-driven steroid metabolism using a sensitive liquid chromatography-mass spectrometry assay. In summary, the PZ and TZ of human prostate exhibited similar steroidogenic ability with distinction in the manner each zone utilizes the steroid precursors to divert the activity towards backdoor pathway through a complex matrix of steroidogenic mechanisms.AlumniNon UBCMedicine, Faculty ofUrologic Sciences, Department ofReviewedFacult
Epidermal Growth Factor Receptor in Prostate Cancer Derived Exosomes
<div><p>Exosomes proteins and microRNAs have gained much attention as diagnostic tools and biomarker potential in various malignancies including prostate cancer (PCa). However, the role of exosomes and membrane-associated receptors, particularly epidermal growth factor receptor (EGFR) as mediators of cell proliferation and invasion in PCa progression remains unexplored. EGFR is frequently overexpressed and has been associated with aggressive forms of PCa. While PCa cells and tissues express EGFR, it is unknown whether exosomes derived from PCa cells or PCa patient serum contains EGFR. The aim of this study was to detect and characterize EGFR in exosomes derived from PCa cells, LNCaP xenograft and PCa patient serum. Exosomes were isolated from conditioned media of different PCa cell lines; LNCaP xenograft serum as well as patient plasma/serum by differential centrifugation and ultracentrifugation on a sucrose density gradient. Exosomes were confirmed by electron microscopy, expression of exosomal markers and NanoSight<sup>™</sup> analysis. EGFR expression was determined by western blot analysis and ELISA. This study demonstrates that exosomes may easily be derived from PCa cell lines, serum obtained from PCa xenograft bearing mice and clinical samples derived from PCa patients. Presence of exosomal EGFR in PCa patient exosomes may present a novel approach for measuring of the disease state. Our work will allow to build on this finding for future understanding of PCa exosomes and their potential role in PCa progression and as minimal invasive biomarkers for PCa.</p></div
EGFR in PCa derived-exosomes.
<p>EGFR was present in exosomes derived from <b>a) panel</b> of AR-responsive and AR-unresponsive as well as benign prostate epithelial cells (RWPE-1) and compared with cell lysate, <b>b)</b> Control nude mouse and LNCaP xenograft serum. <b>c)</b> EGFR is contained in exosomes derived from four different PCa patients’ plasma (1–4), 3 serum samples (5–7) and control subject and in unprocessed plasma from control subject and patient (1 and 2). <b>d)</b> The expression of EGFR at 170kDa and 110kDa in serum and plasma is increased with increasing loading protein concentration. Interestingly, there is a significant amount of EGFR in unprocessed plasma which is in addition to the exosomal fraction. The histogram <b>(e)</b> shows EGFR levels (ng/ml) measured by ELISA in unprocessed plasma from control subject and PCa patient plasma/serum and exosomes derived from corresponding plasma/serum. The levels of serum EGFR are relatively similar in control and PCa subjects whereas exosomes isolated from PCa patient serum contained significantly higher amounts of EGFR than the control subject. Data represented as mean ±SEM, *p<0.05.</p
Exosome isolation from plasma is validated by the presence of exosome markers.
<p><b>a)</b> CD9 was present in exosomes derived from LNCaP xenograft mice bearing small, medium and large LNCaP tumours whereas the control mouse serum lacked CD9. GRP94, a known endoplasmic reticulum protein which is used as a negative control was absent in the exosomes suggesting enrichment <b>b)</b> LAMP2 was present in exosomes derived from PCa patient plasma whereas absence of LAMP2 in whole plasma indicated successful enrichment. <b>c)</b> Alix was present in exosomes derived from patient plasma at different exosomal protein concentrations.</p
Information of PCa plasma and serum used to derive exosomes.
<p>Information of PCa plasma and serum used to derive exosomes.</p
Representative graphs of NanoSight<sup>™</sup> particle tracking analysis.
<p>The analysis showed that mean size of exosomes isolated from control mouse was 126 nm <b>(a)</b> whereas LNCaP xenografted mice bearing small tumour was 81nm (b), 137 nm from medium <b>(c)</b> and 67 nm from large tumours <b>(d)</b>. The concentration of exosomes secreted increased with the increasing size of the tumour.</p