Results of the FLAC European Database of Metastatic Castration-Resistant Prostate Cancer Patients Treated With Docetaxel, Cabazitaxel, and Androgen Receptor-Targeted Agents.

BACKGROUND: Several agents have demonstrated an overall survival (OS) benefit in patients with metastatic castration-resistant prostate cancer (mCRPC); however, the optimal sequencing of these therapies is unknown as a result of a lack of prospective randomized controlled trials. This retrospective study aimed to identify clinical factors influencing outcomes and to determine optimal treatment sequencing in patients with mCRPC treated with cabazitaxel (CABA) and/or androgen receptor-targeted agents (ART) after androgen-deprivation therapy (ADT) and docetaxel (DOC). PATIENTS AND METHODS: Records of 574 consecutive patients treated (2012-2016) at 44 centers in 6 countries were retrospectively examined. RESULTS: A total of 267 patients received ADT → DOC → CABA (group 1), 183 patients ADT → DOC → ART → CABA (group 2), and 124 patients ADT → DOC → CABA → ART (group 3), with respective median OS from diagnosis of mCRPC of 38.3, 44.45, and 53.9 months (P = .012 for group 3 vs. group 1). Multivariate analysis showed response to first ADT ≤ 12 months, Gleason score of 8 to 10, clinical progression, and high prostate-specific antigen levels at mCRPC diagnosis were associated with worse OS. Prior receipt of ART did not influence activity of CABA. CONCLUSION: OS appeared to increase with the number of life-extending therapies, with a sequence including DOC, CABA, and an ART providing the greatest OS benefit.

Targeting of CYP17A1 Lyase by VT-464 Inhibits Adrenal and Intratumoral Androgen Biosynthesis and Tumor Growth of Castration Resistant Prostate Cancer.

Cytochrome P450 17α-hydroxylase/17,20-lyase (CYP17A1) is a validated treatment target for the treatment of metastatic castration-resistant prostate cancer (CRPC). Abiraterone acetate (AA) inhibits both 17α-hydroxylase (hydroxylase) and 17,20-lyase (lyase) reactions catalyzed by CYP17A1 and thus depletes androgen biosynthesis. However, coadministration of prednisone is required to suppress the mineralocorticoid excess and cortisol depletion that result from hydroxylase inhibition. VT-464, a nonsteroidal small molecule, selectively inhibits CYP17A1 lyase and therefore does not require prednisone supplementation. Administration of VT-464 in a metastatic CRPC patient presenting with high tumoral expression of both androgen receptor (AR) and CYP17A1, showed significant reduction in the level of both dehydroepiandrosterone (DHEA) and serum PSA. Treatment of a CRPC patient-derived xenograft, MDA-PCa-133 expressing H874Y AR mutant with VT-464, reduced the increase in tumor volume in castrate male mice more than twice as much as the vehicle (P < 0.05). Mass spectrometry analysis of post-treatment xenograft tumor tissues showed that VT-464 significantly decreased intratumoral androgens but not cortisol. VT-464 also reduced AR signaling more effectively than abiraterone in cultured PCa cells expressing T877A AR mutant. Collectively, this study suggests that VT-464 therapy can effectively treat CRPC and be used in precision medicine based on androgen receptor mutation status.

Differential transcriptional and protein expression of thyroid-stimulating hormone receptor in ovarian carcinomas.

OBJECTIVE: Thyroid-stimulating hormone (TSH) regulates normal thyroid function by binding to its receptor (thyroid-stimulating hormone receptor -TSHR) that is expressed at the surface of thyroid cells. Recently, it has been demonstrated that TSHR is abundantly expressed in several tissues apart from the thyroid, among them the normal ovarian surface epithelium. The role of TSHR expression outside the thyroid is not completely understood. The current study examines possible alterations of TSHR expression in ovarian carcinomas and its implication in ovarian carcinogenesis. MATERIALS AND METHODS: Quantitative real-time polymerase chain reaction and immunohistochemistry analysis of TSHR expression were performed in 34 ovarian carcinoma specimens and 10 normal ovarian tissues (controls). RESULTS: Significant reduction in TSHR messenger RNA (mRNA) expression was detected in ovarian carcinomas (mean [SD]: 0.518 [0.0934] vs normal, 49.4985 [89.1626]; P < 0.001, Mann-Whitney U test), whereas TSHR protein levels were significantly increased (percentage of positive cells: cancer, 73.55% [20.09%], vs normal, 54.54% [21.14%]; intensity: cancer, 2.52 [0.508], vs normal 1 [0]; P = 0.012, Mann-Whitney U test). No significant differences in TSHR mRNA were found according to history of thyroid disease. CONCLUSIONS: Our study describes for the first time alterations in TSHR expression both at mRNA and protein levels in ovarian carcinomas. The discrepancy between the decreased levels of the TSHR mRNA and the increased protein expression has already been described in thyroid carcinomas and might be due to alterations in its degradation by the ubiquitin system or other unknown mechanisms. Further analysis could elucidate the role of these findings in ovarian carcinogenesis.