Hortobagyi, G. N.

Abstract Purpose: Statins may mediate suppression of molecular pathways conferring benefit in cancer. Statins have shown anti-tumor effects in preclinical studies and have been associated with decreased recurrence and improved disease-specific survival. While designed to target cholesterol biosynthesis, statins can also have liver, bone and brain effects. We collected data on statin use in the S0307 adjuvant bisphosphonate trial to test the hypothesis that statin use may decrease risk of recurrence to liver, bone and brain as well as second primary (contralateral) breast cancers, and may act synergistically with bisphosphonates to decrease the risk of recurrence to bone. Patients and Methods: In S0307, 6097 patients diagnosed with Stage I-III breast cancer who had undergone surgery and were receiving adjuvant systemic therapy were randomized to receive zoledronic acid, clodronate, or ibandronate for 3 years. No significant difference was found in disease-free survival (DFS) among the 3 groups, including a sub-analysis of patients > age 55. Statin use was infrequent in younger women in S0307, consequently we analyzed statin use in those > age 55. Cox proportional hazard models were used to determine which variables were independently associated with DFS and to estimate hazard ratios (HR) and 95% confidence intervals (CI). Results: Among women aged ≥ 55 years, 684 (27%) reported taking a statin at baseline and 1,848 did not. Both groups were similar in terms of hormone receptor and HER2 status (p = 0.82). Median age in the statin group was 64.3 versus 61.0 years in the no statin group, mean BMI 31.2 v. 29.5, mean tumor size 2.1cm v. 2.3cm, negative lymph nodes 60% v. 54%, Stage I disease 47% v. 36%, and receipt of chemotherapy 62% v. 71% (all p < 0.01). In the statin group, 122 (17.8%) experienced a DFS event compared to 313 (16.9%) in the no statin group (HR 1.18, CI 0.95-1.46). No difference was observed by statin use in overall recurrence (p=0.28), distant recurrence (p=0.64), or recurrences to the bone (p=0.64), liver (p=0.38) or brain (p=0.65) at initial recurrence. There was no synergy between statin use and specific bisphosphonates. Recurrence and statin useOutcomeGroup 1: On stan at baseline n=684Group 2: No statin at baseline n=1848DFS events122 (17.8%)313 (16.9%)Died without recurrence51 7.5%)97 (5.2%)Recurrence71 (10.4%)216 (11.7%)Contralateral breast cancer9 (1.3%)17 (0.9%)Distant recurrence48 (7%)157 (8.5%)Bone as 1st site of distant recurrence (% distant recurrence)31 (65%)76 (48%)Liver as 1st site of distant recurrence (% distant recurrence)6 (13%)24 (16%)Brain/CNS as 1st site of distant recurrence (% distant recurrence)5 (10%)17 (11%) Conclusions: We found no evidence that statins reduce risk of second primary breast cancers or distant metastases among post-menopausal women with early-stage breast cancer. Despite promising preclinical data, they did not appear to act in synergy with a specific bisphosphonate. Though women in the statin group had less advanced disease at study entry, statin use was not associated with improved DFS. Results are limited by lack of information about type of statin used, adherence, or initiation of statin in control group. Citation Format: Kizub D, Miao J, Stopeck A, Thompson P, Paterson AH, Clemons M, Dees EC, Ingle JN, Falkson CI, Barlow W, Hortobagyi GN, Gralow JR. Statin use, site of recurrence, and survival among post-menopausal women taking bisphosphonates as adjuvant therapy for breast cancer (SWOG S0307) [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P1-17-03.

Abstract BACKGROUND: Unique genes and pathways were identified for prognosis on tamoxifen (T, 5 yrs) and prediction on CAF-T vs T in S8814 using whole transcriptome RNA-Seq from archival FFPE tissue. (Albain, et al; Cherbavaz, et al; SABCS 2015) Discovery was robust for early DFS events but sparse for late. The aims of this new analysis were to 1) utilize a new endpoint BCSE for gene discovery of late events, prognosis and prediction and 2) add intronic counts to the previous exonic results to define whole genes impacting on late BCSE. METHODS: Charts of patients (pts) on CAF-T (212) vs T (142) were reviewed to define the BCSE endpoint (local/regional, contralateral, distant). Deaths without BC were treated as competing risks. BCSE models (including metagenes) of late prognosis and prediction used cumulative incidence functions. Consolidated intronic regions counts within genes were added to exonic regions counts. Using these “whole gene” (WG) counts, association of gene expression with time to BCSE was assessed by Cox regression. A multiple WG score (MWGS) for BCSE prognosis beyond 5 yrs (to 12.5 yrs) was constructed and evaluated for 1-3 and 4+ node (N) groups. False discovery rate was controlled at 10%. RESULTS: More exons and WG were discovered for prognosis on T alone over 12.5 yrs with the BCSE endpoint than DFS. For prognosis of late BCSE after 5 yrs, more genes were discovered using WG (n=111) than by exons (n=9). There were significantly fewer genes for late BCSE on CAF-T (8, WG; 0, exons). The functions of WG prognostic for late BCSE were: cell cycle/proliferation-26 genes, chromosome segregation/mitotic spindle-22, DNA repair/maintenance-10, transcriptional/translational control-5, cell adhesion/migration-4, immune-3, diverse/unknown-32 and growth factor/hormone receptor signaling-9 (this group was only found by WGs, not exons). Of these 111 WG, a MWGS prognostic for late BCSE on T used 57 previously discovered genes pre-specified for this analysis. Probability of BCSE beyond 5 yrs for low vs high MWGS was 8% vs 21% in N1-3+ and 17% vs 42% in N4+. Late prognosis on T differed by low vs high risk defined in a metagene model: cumulative BCSE at year 10 was 0% vs 47% (low vs high risk, p=0.001). Prediction of 10-yr incidence of BCSE varied by risk level by treatment in a metagene model: low risk- CAF-T=47%, T=0% (p=0.045); high risk- CAF-T=35%, T=45% (p=0.027). CONCLUSIONS: Gene discovery for prognosis of late BCSE is enhanced with a novel WG transcriptome expression approach. Use of chemotherapy (CT) before T significantly attenuated gene discovery, so that molecular tools for decisions on extending endocrine therapy (ET) may not be reliable in a setting of prior CT. Some pts on ET for 5 yrs may not require either longer ET or CT, given a N+ cohort was defined with no BCSE observed over 12.5 yrs. For prediction of CT benefit, CAF-T appeared to be inferior to T in a low risk metagene model for BCSE. In sum, these results add more evidence that ET alone may be sufficient (perhaps better) in select N+ settings. Validation in SWOG S1007 (RxPONDER) is planned. SUPPORT: NCI CA180888, 180819, 180821, 180820, 180863; in part, Genomic Health, Inc. Citation Format: Albain KS, Crager MR, Barlow WE, Baehner FL, Bergamaschi A, Rae JM, Ravdin PM, Tripathy D, Gralow JR, Livingston RB, Osborne CK, Ingle JN, Pritchard KI, Davidson NE, Carey LA, Cherbavaz DB, Sing AP, Shak S, Hortobagyi GN, Hayes DF. Discovery of molecular predictors of late breast cancer specific events (BCSE) in ER+, node+ breast cancer – new transcriptome expression whole gene analysis of the phase III adjuvant trial SWOG S8814 [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr PD7-07.

Abstract BACKGROUND: In SWOG-8814A, pts with ER+ node+ breast cancer and low 21 gene recurrence scores (RS) had good prognosis and no CAF benefit, but high RS predicted longer survival from CAF followed by T (CAF-T) vs T (Albain, Lancet Oncol 2010). The aims of SWOG-8814B were to identify novel genes and networks for 1) prognosis of early and late relapse and 2) prediction of CAF benefit, using whole transcriptome expression analysis with next generation RNA sequencing (NGS). METHODS: Stored RNA previously extracted for SWOG-8814A (T, CAF-T arms; T, 5 yrs) was analyzed for RNA/library yield (see companion abstract Cherbavaz et al. for methods). Genes were sequenced and expression of mRNA species was related to disease-free survival (DFS) using Cox proportional hazards. Discovery analyses controlled false discovery rate (FDR) at 10%. Genes were identified for prognosis on T and prediction on CAF-T vs T. Networks of genes/pathways were explored. Early (0-5 yrs) and late (5-13+ yrs) time periods were studied. Gene Ontology, Cytoscape, pathway and hierarchical clustering were used for functional gene and metagene analyses. RESULTS: Of 367 samples, 354 (96%; 142 T, 212 CAF-T; 141 DFS events) had sufficient RNA/library yield, with 20,101 genes sequenced. For prognosis on T, there were 2327 and 568 genes discovered in early and all-yrs follow-up, with only 9 genes prognostic after 5 yrs. Prognosis analyses for residual risk after CAF-T were uninformative. Functional mapping found that genes prognostic for worse DFS were enriched for proliferation (G2M, M-phase), cellular metabolism, DNA repair, stress response and EMT; whereas, those with better DFS involved transcription regulation/repression via zinc finger proteins. Hierarchical clustering (T arm) found significant DFS prognostic metagene signatures for ER-related genes, immune response, ECM/stroma, chromatin remodeling-transcription factor activity and TGFb pathway. All varied for early vs late DFS events. For example, low ER/high stroma expression signatures correlated with high proliferation gene expression and were strongly associated with early events (standardized [st] HR 2.94, p<0.001). Late recurrence was associated with high proliferation, both individually (stHR 1.51, p=.035) and in combination with higher ER expression (stHR 1.51, p=0.09). Fifteen genes predicted CAF benefit (9 better DFS, 6 worse), or 129 genes if FDR relaxed to 20%. Cluster analysis for CAF prediction is ongoing. CONCLUSIONS: Unique genes, clusters and pathways were identified by NGS of archival material in ER+ N+ breast cancer, including previously unreported signatures. While ER, stroma and proliferation-related signatures were associated with early prognosis, proliferation best predicted worse DFS after 5 yrs. NGS of the primary tumor is most informative for early events in pts with only 5 years of T, with few genes selecting only for late relapse. If validated, these signatures may identify pts with excellent DFS despite positive nodes for endocrine therapy alone as well as others for whom chemotherapy and/or biologics are also required . SUPPORT: NCI CA 180888, 180819, 180821, 180820, 180863; in part, Genomic Health, Inc. Citation Format: Albain KS, Crager MR, Barlow WE, Baehner FL, Bergamaschi A, Rae JM, Ravdin PM, Tripathy D, Gralow JR, Livingston RB, Osborne CK, Ingle JN, Pritchard KI, Davidson NE, Carey LA, Cherbavaz DB, Sing AP, Shak S, Hortobagyi GN, Hayes DF. Molecular predictors of outcome on adjuvant CAF plus tamoxifen (T) vs T in postmenopausal patients (pts) with ER+, node+ breast cancer – Transcriptome expression analysis of the phase III trial SWOG-8814. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr S3-02.