Sagar D Sardesai1, Alexandra Thomas2, Christopher Gallagher3, Filipa Lynce4, Yvonne Lynn Ottaviano5, Tarah Jean Ballinger6, Bryan P Schneider6, Anna Maria Storniolo6, Amber Bauchle6, Sandra K Althouse6, Susan M Perkins6, Andrea R Masters6, Robert E Stratford6, Zizheng Dong7, Jing-Yuan Liu8, Jian-Ting Zhang7, Kathy D Miller6.
Abstract
PURPOSE: Fatty acid synthase (FASN) is overexpressed in 70% of operable triple-negative breast cancer (TNBC) and is associated with poor prognosis. Proton pump inhibitors selectively inhibit FASN activity and induce apoptosis in TNBC cell lines. PATIENTS AND METHODS: Patients with operable TNBC were enrolled in this single-arm phase II study. Patients began omeprazole 80 mg orally twice daily for 4-7 days prior to neoadjuvant anthracycline-taxane-based chemotherapy (AC-T) and continued until surgery. The primary endpoint was pathologic complete response (pCR) in patients with baseline FASN overexpression (FASN+). Secondary endpoints included pCR in all surgery patients, change in FASN expression, enzyme activity, and downstream protein expression after omeprazole monotherapy, safety, and limited omeprazole pharmacokinetics.
RESULTS: Forty-two patients were recruited with a median age of 51 years (28-72). Most patients had ≥cT2 (33, 79%) and ≥N1 (22, 52%) disease. FASN overexpression prior to AC-T was identified in 29 of 34 (85%) evaluable samples. The pCR rate was 72.4% [95% confidence interval (CI), 52.8-87.3] in FASN+ patients and 74.4% (95% CI, 57.9-87.0) in all surgery patients. Peak omeprazole concentration was significantly higher than the IC50 for FASN inhibition observed in preclinical testing; FASN expression significantly decreased with omeprazole monotherapy [mean change 0.12 (SD, 0.25); P = 0.02]. Omeprazole was well tolerated with no grade ≥ 3 toxicities.
CONCLUSIONS: FASN is commonly expressed in early TNBC. Omeprazole can be safely administered in doses that inhibit FASN. The addition of omeprazole to neoadjuvant AC-T yields a promising pCR rate that needs further confirmation in randomized studies. ©2021 American Association for Cancer Research.
PURPOSE: Fatty acid synthase (FASN) is overexpressed in 70% of operable triple-negative breast cancer (TNBC) and is associated with poor prognosis. Proton pump inhibitors selectively inhibit FASN activity and induce apoptosis in TNBC cell lines. PATIENTS AND METHODS: Patients with operable TNBC were enrolled in this single-arm phase II study. Patients began omeprazole 80 mg orally twice daily for 4-7 days prior to neoadjuvant anthracycline-taxane-based chemotherapy (AC-T) and continued until surgery. The primary endpoint was pathologic complete response (pCR) in patients with baseline FASN overexpression (FASN+). Secondary endpoints included pCR in all surgery patients, change in FASN expression, enzyme activity, and downstream protein expression after omeprazole monotherapy, safety, and limited omeprazole pharmacokinetics.
RESULTS: Forty-two patients were recruited with a median age of 51 years (28-72). Most patients had ≥cT2 (33, 79%) and ≥N1 (22, 52%) disease. FASN overexpression prior to AC-T was identified in 29 of 34 (85%) evaluable samples. The pCR rate was 72.4% [95% confidence interval (CI), 52.8-87.3] in FASN+ patients and 74.4% (95% CI, 57.9-87.0) in all surgery patients. Peak omeprazole concentration was significantly higher than the IC50 for FASN inhibition observed in preclinical testing; FASN expression significantly decreased with omeprazole monotherapy [mean change 0.12 (SD, 0.25); P = 0.02]. Omeprazole was well tolerated with no grade ≥ 3 toxicities.
CONCLUSIONS: FASN is commonly expressed in early TNBC. Omeprazole can be safely administered in doses that inhibit FASN. The addition of omeprazole to neoadjuvant AC-T yields a promising pCR rate that needs further confirmation in randomized studies. ©2021 American Association for Cancer Research.
Entities:
Mesh:
Substances:
Year: 2021
PMID: 34400413 DOI: 10.1158/1078-0432.CCR-21-0493
Source DB: PubMed Journal: Clin Cancer Res ISSN: 1078-0432 Impact factor: 12.531