PTEN Protein Loss and Clinical Outcome from Castration-resistant Prostate Cancer Treated with Abiraterone Acetate

Publikation

PTEN Protein Loss and Clinical Outcome from Castration-resistant Prostate Cancer Treated with Abiraterone Acetate

Wissenschaftlicher Artikel/Review - 04.11.2014

Ferraldeschi Roberta, Sideris Spyridon, Bianchini Diletta, Grist Emily, Thway Khin, Perez Lopez Raquel, Tunariu Nina, Parker Chris, Dearnaley David, Reid Alison, Attard Gerhardt, Altavilla Amelia, Mateo Joaquin, Nava Rodrigues Daniel, Riisnaes Ruth, Miranda Susana, Figueiredo Ines, Rescigno Pasquale, Ravi Praful, Pezaro Carmel, Omlin Aurelius, Lorente David, Zafeiriou Zafeiris, de Bono Johann

Zitation

Ferraldeschi R, Sideris S, Bianchini D, Grist E, Thway K, Perez Lopez R, Tunariu N, Parker C, Dearnaley D, Reid A, Attard G, Altavilla A, Mateo J, Nava Rodrigues D, Riisnaes R, Miranda S, Figueiredo I, Rescigno P, Ravi P, Pezaro C, Omlin A, Lorente D, Zafeiriou Z, de Bono J. PTEN Protein Loss and Clinical Outcome from Castration-resistant Prostate Cancer Treated with Abiraterone Acetate. Eur Urol 2014

Art

Wissenschaftlicher Artikel/Review (Englisch)

Zeitschrift

Eur Urol 2014

Veröffentlichungsdatum

04.11.2014

eISSN (Online)

1873-7560

Kurzbeschreibung/Zielsetzung

BACKGROUND
Loss of the tumor suppressor phosphatase and tensin homolog (PTEN) occurs frequently in prostate cancers. Preclinical evidence suggests that activation of PI3K/AKT signaling through loss of PTEN can result in resistance to hormonal treatment in prostate cancer.

OBJECTIVE
To explore the antitumor activity of abiraterone acetate (abiraterone) in castration-resistant prostate cancer (CRPC) patients with and without loss of PTEN protein expression.

DESIGN, SETTING, AND PARTICIPANTS
We retrospectively identified patients who had received abiraterone and had hormone-sensitive prostate cancer (HSPC) and/or CRPC tissue available for PTEN immunohistochemical analysis.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS
The primary end point was overall survival from initiation of abiraterone treatment. Relationship with outcome was analyzed using multivariate Cox regression and log-rank analyses.

RESULTS AND LIMITATIONS
A total of 144 patients were identified who had received abiraterone post-docetaxel and had available tumor tissue. Overall, loss of PTEN expression was observed in 40% of patients. Matched HSPC and CRPC tumor biopsies were available for 41 patients. PTEN status in CRPC correlated with HSPC in 86% of cases. Loss of PTEN expression was associated with shorter median overall survival (14 vs 21 mo; hazard ratio [HR]: 1.75; 95% confidence interval [CI], 1.19-2.55; p=0.004) and shorter median duration of abiraterone treatment (24 vs 28 wk; HR: 1.6; 95% CI, 1.12-2.28; p=0.009). PTEN protein loss, high lactate dehydrogenase, and the presence of visceral metastases were identified as independent prognostic factors in multivariate analysis.

CONCLUSIONS
Our results indicate that loss of PTEN expression was associated with worse survival and shorter time on abiraterone treatment. Further studies in larger and prospective cohorts are warranted.

PATIENT SUMMARY
PTEN is a protein often lost in prostate cancer cells. In this study we evaluated if prostate cancers that lack this protein respond differently to treatment with abiraterone acetate. We demonstrated that the survival of patients with loss of PTEN is shorter than patients with normal PTEN expression.