Characterization of Precursor-Dependent Steroidogenesis in Human Prostate Cancer Models

Abstract

Castration-resistant prostate tumors acquire the independent capacity to generate androgens by upregulating steroidogenic enzymes or using steroid precursors produced by the adrenal glands for continued growth and sustainability. The formation of steroids was measured by liquid chromatography-mass spectrometry in LNCaP and 22Rv1 prostate cancer cells, and in human prostate tissues, following incubation with steroid precursors (22-OH-cholesterol, pregnenolone, 17-OH-pregnenolone, progesterone, 17-OH-progesterone). Pregnenolone, progesterone, 17-OH-pregnenolone, and 17-OH-progesterone increased C21 steroid (5-pregnan-3,20-dione, 5-pregnan-3,17-diol-20-one, 5-pregnan-3-ol-20-one) formation in the backdoor pathway, and demonstrated a trend of stimulating dihydroepiandrosterone or its precursors in the backdoor pathway in LNCaP and 22Rv1 cells. The precursors differentially affected steroidogenic enzyme messenger RNA (mRNA) expressions in the cell lines. The steroidogenesis following incubation of human prostate tissue with 17-OH-pregnenolone and progesterone produced trends similar to those observed in cell lines. Interestingly, the formation of C21 steroids from classical pathway was not stimulated but backdoor pathway steroids (e.g., 5-pregnan-3,20-dione, 5-pregnan-3-ol-20-one) were elevated following incubations with prostate tissues. Overall, C21 steroids were predominantly formed in the classical as well as backdoor pathways, and steroid precursors induced a diversion of steroidogenesis to the backdoor pathway in both cell lines and human prostate tissue, and influenced adaptive steroidogenesis to form C21 steroids.

Steroidogenesis in Peripheral and Transition Zones of Human Prostate Cancer Tissue

“…It is worth mentioning that except some very limited radiometry-based studies with human tissues [ 31 , 32 , 38 ], our study evaluated a much wider range of steroids in a convincing manner ( Figure 3 ). The results from the current study are consistent with our previously reported cellular steroidogenesis work which suggested predominance of backdoor pathways following incubation of steroid precursors with LNCaP and 22Rv1 cells for 48 h [ 29 ]…”

“…Steroids were detected using the hydroxylamine derivatization method and quantification was performed by using calibration curve created by derivatized steroid standards at varying concentrations. The internal standards, including trideuterated testosterone (d3T) and trideuterated dihydrotestosterone (d3DHT), offered very good matrix correction for testosterone and DHT, and they were also reasonable for the other ketosteroids profiled with the oxime derivatization as described previously [ 29 ].…”

“…Analysis was performed on a Waters Acquity ultraperformance liquid chromatography (UPLC) coupled to a Quattro Premier XE using a 2.1 × 100 mm BEH 1.7 µM C 18 column as described previously [ 29 ]. MassLynxTM 4.1 (Waters Corporation, Milford, MA, USA) was used for instrument control.…”

“…The enzyme levels and steroidogenic potential within the same cell lines differ based on method of culture, supplementation and test conditions [ 27 , 28 ]. In comparison, mouse xenograft models developed by using human prostate cancer cells are also used to mimic the human prostate tissue steroidogenesis, but mouse tumor microenvironments are responsible for the substantial differences between xenografts and human prostate tumors [ 20 , 29 ]. While cell lines can be monoclonal for a specific cell type, the tissue samples represent a large heterogeneous population of different cell types [ 30 ].…”

Steroidomics for the Prevention, Assessment, and Management of Cancers: A Systematic Review and Functional Analysis

“…Generally, steroidogenesis has been extensively targeted by using inhibitors of steroidogenesis as therapeutic agents for cancer and other diseases [104,105,106]. Recently, the underlying mechanism of steroidogenesis was characterized in castration-resistant prostate cancer cell lines and tissues to provide better insights into steroid substrate utilization [107]. Moreover, differential gene expressions related to androgen and estrogen metabolism were explored between hereditary and sporadic prostate cancer [108].…”