AR-V7 negative

P2, N=223, Active, not recruiting, ECOG-ACRIN Cancer Research Group | Trial primary completion date: Dec 2024 --> Mar 2025

Conclusions The benefit of continuing ENZ beyond progression with Doc vs Doc alone is greatest in patient with no evidence of plasma AR gain or AR-V7+ CTC. Plasma tumor DNA detection after 3 weeks Doc +/- ENZ identifies patients with shorter PFS.

At this early stage, independently to ADT administration, AR-V7 positivity is associated to risk classification and it can predict biochemical and radiological progression after surgery. Validation of our findings in a larger cohort will be relevant for further studies to define a subset of PC cases submitted to RP in which intensification of adjuvant treatments could be indicated.

Baseline CTC biomarkers may be prognosticators for cabazitaxel-treated mCRPC patients. Cabazitaxel at lower (20 mg/sqm) dose was associated with poorer outcomes in AR-V7 positive patients compared to AR-V7 negative patients in a post hoc subgroup analysis.

P2, N=32, Completed, Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins | N=15 --> 32

Using ultra-deep targeted RNA-Seq, we provide among the first comprehensive descriptions of the ARV landscape in primary prostate cancer. Moreover, we show that detectable AR-V7 in prostatectomy specimens was associated with inferior outcomes following salvage RT+ADT, suggesting for the first time that AR-V7 may modulate outcomes for localized as well as metastatic disease. Ongoing work includes comparison with Decipher score and validation in independent cohorts.

Using a custom ultra-deep targeted RNA-Seq approach, we provide among the first comprehensive descriptions of the AR splice variant landscape in primary prostate cancer. Moreover, we show that detectable AR-V7 expression in prostatectomy specimens was associated with inferior outcomes following subsequent salvage RT+ADT, suggesting for the first time that AR-V7 may modulate outcomes for localized as well as metastatic disease.

P2, N=15, Completed, Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins | Active, not recruiting --> Completed | Trial completion date: Sep 2022 --> Oct 2021 | Trial primary completion date: Sep 2021 --> Dec 2020

Notably, inhibiting ERG/AR-mediated DLX1 transcription using BET inhibitor (BETi) or/and anti-androgen drugs reduce its expression and downstream oncogenic effects. Conclusively, this study establishes DLX1 as a direct-target of ERG/AR with an oncogenic role and demonstrates the clinical significance of BETi and anti-androgens for DLX1-positive patients.

We conclude that positive AR IHC and apocrine morphology are pathologic features that may indicate testing for AR-V7 is warranted in both primary and metastatic BC in the appropriate clinical context. The study findings further encourage the assessment of AR-V7 as a predictive biomarker for AR antagonist benefit in ongoing clinical BC trials.

The results of this meta-analysis, the first in literature to be specifically focused on this topic so far, suggest that AR-V7 positivity may be associated with any site metastases and bone metastases; conversely, no association has been highlighted between AR-V7 expression and lymph node or visceral metastases. Although this meta-analysis should be interpreted with caution due to some limitations, our findings confirm that AR-V7 status could designate a unique and peculiar subtype of PC. Further studies aimed at improving and standardizing AR-V7 detection in clinical trials on CRPC patients are warranted.