Citations

Abstract Purpose: Tamoxifen and raloxifene, are primary prevention strategies for women at high risk of breast cancer (Visvanathan, 2013). Recent advances in genetic studies of breast cancer risk have identified common susceptibility loci that explain 14% of familial risk for breast cancer in the general population (Michailidou, 2013). However, it is not known if these loci are risk factors for breast cancer among high-risk women treated with SERMs for breast cancer prevention. We hypothesized that the large risk reduction associated with SERMs, coupled with the fact that several breast cancer loci correlate with family history, may limit the contribution of these common genetic loci to breast cancer in this high risk population. We present the first report to evaluate 75 established breast cancer susceptibility loci, in the context of a polygenic risk score (PRS), as a risk factor for breast cancer among high risk women taking raloxifene and tamoxifen for breast cancer prevention. Methods: We conducted a matched case-control study of 594 cases (i.e., participants who developed breast cancer while on SERM therapy) and 1,171 matched controls selected from the 33,000 participants enrolled in the NSABP P-1 and P-2 breast cancer prevention trials. Genotypes of 75 single nucleotide polymorphisms (SNPs) were available from a genome-wide association study conducted at the RIKEN Center for Genomic Medicine. We formed a quantitative PRS from reported per-SNP odds ratios (OR) for the 75 susceptibility loci. Conditional logistic regression was used to examine the PRS as a risk factor for breast cancer and to assess whether the PRS and breast cancer association differed by treatment type, family history, or other clinical characteristics. Analyses also examined associations of PRS with invasive vs. in situ cancer and ER-positive vs. ER-negative cancer. Results: The PRS ranged from 3.98 to 7.74, and a one unit change in PRS was associated with a 42% increase in breast cancer (OR=1.42; 95% CI: 1.18-1.70; P = 0.0002). There was evidence of a stronger association of PRS with breast cancer among women with no first-degree family history (OR=1.62, 95% CI: 1.18-2.21) compared to those with a positive family history (OR=1.32, 95% CI: 1.06-1.66) (Pintx<0.05). The PRS also appeared a stronger risk factor for ER-positive (OR=1.59, 95% CI: 1.25-2.02, P < 0.0002) vs. ER-negative (OR=1.05, 95% CI: 0.68-1.62, P=0.84) breast cancer, although differences did not reach statistical significance (Pintx=0.10). PRS and breast cancer associations were similar across tamoxifen and raloxifene treatments, age at trial entry, 5-year predicted Gail model risk, hysterectomy status, BMI, presence of atypical hyperplasia and invasive vs. in situ cancer. Conclusion: A polygenic risk score composed of 75 loci was a risk factor for ER-positive breast cancer, especially in the absence of a first-degree family history of breast cancer. Further, the PRS associations with breast cancer were similar for women taking tamoxifen or raloxifene for prevention. These data suggest that common genetic variation adds information on risk of ER-positive breast cancer in a high-risk population receiving SERMs. Citation Format: Celine M Vachon, Daniel J Schaid, James N Ingle, Matthew P Goetz, Donald L Wickerham, Michiaki Kubo, Erin E Carlson, Soonmyung Paik, Norman Wolmark, Yusuke Nakamura, Liewei Wang, Richard M Weinshilboum, Fergus J Couch. The contribution of common genetic variation to breast cancer risk among women receiving tamoxifen or raloxifene within the National Surgical Adjuvant Breast and Bowel Project (NSABP) P-1 and P-2 trials [abstract]. In: Proceedings of the Thirty-Seventh Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2014 Dec 9-13; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2015;75(9 Suppl):Abstract nr P6-10-03.

Abstract Background: While the biological functions and clinical importance of ERα are well understood in breast cancer, much less is known about its most closely related family member, ERβ, particularly in the setting of triple negative disease. Additionally, the ability to therapeutically target ERβ in triple negative breast cancer (TNBC) has not been fully explored. Methods: Expression of ERβ protein was determined using a well characterized and validated ERβ specific monoclonal antibody that only recognizes the full-length form of this receptor (PPG5/10) in a cohort of 71 TNBCs. To further define the biological functions of ERβ in TNBC, novel ERβ expressing triple negative cell lines (MDA-MB-231 and Hs578T) were developed and comprehensively characterized at the level of global gene expression profiling, modulation of important biological pathways, cellular proliferation and response to targeted therapies. Results: In TNBCs from 71 patients, nuclear and cytoplasmic ERβ was detected at moderate to high levels in 24% and 32% of cases respectively. This moderate to high expression of both nuclear and cytoplasmic ERβ was associated with higher levels of Ki67. Of the 17 tumors expressing ERβ, 13 (76%) were negative for androgen receptor expression. In the triple negative MDA-MB-231-ERβ and Hs578T-ERβ cell lines, expression of ERβ led to inhibition of proliferation in response to both estrogen and multiple ERβ specific agonists. Microarray analysis and RT-PCR profiling of these cells revealed that estrogen and ERβ agonists highly induced the expression of multiple cystatins, a family of small secreted cysteine protease inhibitors, while suppressing the expression of many interleukins. Conditioned media isolated from estrogen or ERβ agonist treated MDA-MB-231-ERβ cells inhibited the proliferation rates and blocked TGFβ signaling in non-ERβ expressing TNBC cells, effects that were completely reversed following depletion of cystatins from the conditioned media. Conclusions: ERβ is expressed in a substantial proportion of TNBCs, and most do not express the androgen receptor. In TNBC, where targeted therapies are lacking, our data suggest that estrogen or ERβ specific agonists would be expected to elicit anti-tumor effects when ERβ is expressed. These tumor suppressive effects of ERβ appear to be mediated in part through the actions of cystatins, and their inhibition of TGFβ signaling, suggesting that this family of secreted proteins may represent novel biomarkers for monitoring ERβ specific drug responsiveness and/or patient outcomes. Citation Format: Jordan M Reese, Malayannan Subramaniam, Vera J Suman, Xianglin Wu, Vivian Negron, Anne Gingery, Kevin S Pitel, Sejal S Shah, Heather E Cunliffe, Ann E McCullough, Barbara A Pockaj, Thomas C Spelsberg, Matthew P Goetz, James N Ingle, John R Hawse. Therapeutic targeting of ERβ in triple negative breast cancer [abstract]. In: Proceedings of the Thirty-Seventh Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2014 Dec 9-13; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2015;75(9 Suppl):Abstract nr P6-03-06.

Abstract Background: Triple negative breast cancer (TNBC) represents 15% of all breast cancers, and is characterized by an aggressive clinical course. While efforts are ongoing to characterize the molecular basis for variation in TNBC, there are conflicting data regarding the impact of prognostic factors such as age and Ki-67 typically used for treatment decisions in other breast cancer subtypes. We identified a retrospective cohort of women with ER- breast cancer with long term follow-up, and performed central confirmation of ER, PR, HER2, Ki-67 and histological classification to assess the association of Ki-67 and histologic subtype on clinical outcome in TNBC pateints (pts). Methods: 9,836 women who underwent breast cancer surgery at Mayo Clinic Rochester from 1985-2005 were identified. Pts were excluded due to: ER+ disease (7363); prior cancer (553); non-invasive disease (465); bilateral breast cancer (167); metastatic disease [at diagnosis or within 60 days of surgery (110)]; ER- disease treated with neoadjuvant chemotherapy (121) or adjuvant hormonal therapy (112); or tumor block exhausted (94). For all others, centralized ER/PR/HER2 identified the following for exclusion, >1% ER staining (n=76), > 1% PR (n=14) and HER2+ (n=144) by IHC (3+) or FISH amplification. 225 cases are still undergoing review. For the centrally confirmed pts with TNBC (n=392), Ki-67 and histological characterization (WHO subtypes) were assessed. Results: Patient characteristics are listed in the table. The median age for all TNBC’s was 45 (range 29-88) and nearly all tumors were grade 3 (91%) with high proliferation (63% with Ki-67 > 30%). The median follow-up was >10 years, where 139 pts had a disease event: progression (86) or second primary (53) and 53 died without a disease event. The 10 yr DFS rate was 55.8% (95%CI: 48.8-63.9%) among the 238 pts who did not receive adjuvant chemotherapy (AdjCT) and 58.9% (95% CI: 48.9-70.9%) among the 102 pts administered AdjCT. In pts without adjCT, DFS was found to differ with respect to number of positive LNs (0 vs. 1-4 vs. 4+; log rank p=0.003) and medullary histology (log rank p=0.015) but not with age (< 50 vs. ≥ 50), tumor size (< 2.0 vs. 2-5 vs. ≥ 5.0 cm) or Ki-67 (0-15% vs. 15.1-30% vs. >30 %). Conclusions: Our findings confirm the poor prognosis of TNBC. The medullary histological subtype is associated with significantly better prognosis than other TNBC subtypes (10 year DFS rate of 78.5%; 95%CI: 59.1-99.9% in pts not treated with adjCT). After central confirmation, neither age nor Ki-67 provide additional prognostic information. Patient characteristicsMedian Age (range)45(29-88) n%Histology Apocrine287.1Carcinoma, anaplastic or undiffrentiated9323.7Central scar/necrotizing348.7Clear Cell297.4Infiltrating ductal ca7118.1Large Cell neuroendocrine143.6Medullary and atypical medullary4311.0Metaplastic ca246.1Trabecular ca338.4other histologies235.9Grade 130.82317.9335891.3Tumor Size 0.1-2 cm19650> 2.0 cm19549.6not stated10.3Nodal status 0251641-38220.94-9338.410+225.6not evaluated41.0Ki-67 0-157719.615.1-306516.6>30%24763.3not done20.5Adjuvant Chemotherapy Yes10226.0No23860.7unknown5213.3 Citation Format: Ahmed Elkhanany, Vera J Suman, Victoria Cafourek, Judith A Gilbert, James N Ingle, Fergus Couch, Daniel W Vissscher, Matthew P Goetz. Triple negative breast cancer: The role of classic histological and prognostic factors on disease free survival [abstract]. In: Proceedings of the Thirty-Seventh Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2014 Dec 9-13; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2015;75(9 Suppl):Abstract nr P5-02-11.

Abstract [Background] Patient advocates bring a unique, valuable perspective and presence to SPOREs. However, although patient advocates are recommended members of SPORE grants, guidelines are not given on the role of advocates or on measurement of the performance of advocates. [Methods] The Mayo Clinic Breast Cancer SPORE Patient Advocate Advisory Committee has developed a participation measurement tool. This tool will underpin and augment evaluations of the individual advocate contributions by the program PI and the SPORE project leaders. The Advocate Advisory Committee Chair will review the evaluations with the individual advocates. Annually, the advocate committee will review the performance of the group by the standard of the metrics. [Results] Advocates kept a log of their SPORE activities for four months then worked with a statistician to discern patterns of measurable, evaluable behaviors. The determined evaluable areas are training, scientific activity, meeting attendance, communication. Currently, those metrics are being tracked. Advocates developed the metrics together and report activities at the monthly advocate meetings. Currently, activities are simply tracked and categorized. No minimum standards are set. This will be the third step in the development of the metrics. [Conclusions] This approach is the first step in the development of meaningful evaluation of advocate SPORE activities. It quantifies the participation of advocates in the SPORE and provides the basis for developing a qualitative performance evaluation. The SPORE PI and the Committee Chair will use the evaluations to interpret the involvement of advocates in SPORE research and activities and to plan interventions to strengthen the advocate contributions to the SPORE. Citation Format: Cynthia Chauhan, Wayland Eppard, Lori Denison, Debra Gearhart, Lawanna Holmes, Ruth Kraft, Linda Miller, Mary A Sitta, Mary L Smith, James Ingle, Matthew Goetz. Measurements of advocate participation in and contributions to the Mayo Clinic breast cancer SPORE [abstract]. In: Proceedings of the Thirty-Seventh Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2014 Dec 9-13; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2015;75(9 Suppl):Abstract nr P2-09-04.

Abstract Endocrine therapy, with SERMs and AIs, is the most important treatment modality for the 70% of patients with ER+ early breast cancer. Clinically, there is marked variability between patients in response to treatment and adverse events (AEs) such as musculoskeletal (MS) AEs with AIs. In 649 women with early-stage breast cancer we identified large inter-individual variations in pretreatment and on-anastrozole (A) plasma estrogens as well as plasma A concentrations, suggesting that the approved A dose of 1 mg per day may not be optimal for all patients. We performed a series of genome-wide association studies (GWAS) and identified a genome-wide significant variant SNP associated with concentrations of E2 that created an estrogen response element (ERE), and a significant SNP associated with E1-conjugates, providing potential insights into the variability. Pharmacogenomics (PGx) is the study of the role of germline and somatic genetic variation in individual variability in drug response phenotypes, i.e., disease response and AEs. The scientific goal is to understand mechanisms for the phenotype and the clinical goal is the determination of the right drug at the right dose for the right patient. The Mayo PGx Research Network Center and Breast SPORE and the RIKEN Center for Integrative Medical Science have worked collaboratively with cooperative groups to perform GWAS in women treated with both SERMs and AIs. The PGx paradigm consists of the GWAS as the initial step in a process that goes beyond the identification of associations to study the relationship of the single nucleotide polymorphisms (SNPs) to genes and the relationships of these SNPs and genes to the drug effect and the phenotype under study. Using the phenotype of AI-related MS-AEs, the major reason women stop therapy, a case-control GWAS was performed with patients from MA.27. The GWAS identified a SNP on chromosome (Chr) 14 that was associated with MS-AEs, near a gene (TCL1A), and created an ERE. Importantly, TCL1A expression was related to expression of multiple cytokine receptors, NFκB, and chemokines (related to rheumatoid arthritis) in an E2- and SNP-dependent fashion. These results provide a pharmacogenomic basis for MS-AEs with AIs. Using the phenotype of development of breast cancer in high-risk women receiving SERMs, a case-control GWAS was performed with patients entered on the NSABP P-1 and P-2 trials. The GWAS revealed variant SNPs on Chr 4 near CTSO (deleterious) and Chr 16 in ZNF423 (protective). The OR for differences in risk of breast cancer for participant homozygous for both protective or both deleterious alleles was 5.71. Both CTSO and ZNF423 were shown to participate in E2-dependent induction of BRCA1 expression in a SNP-dependent fashion. Most remarkable was that the presence of a SERM reversed the E2-inducible expression of ZNF423 and BRCA1 in a SNP-dependent fashion. In addition, ZNF423 was shown to be an E2-inducible BRCA1 transcription factor. The deleterious variant SNP near CTSO was found to disrupt an ERE. The GWAS described led to functional genomic studies that produced new knowledge relating to endocrine biology that provide a focus for further research to move towards precision endocrine therapy for women with breast cancer. Citation Format: James N. Ingle. Pharmacogenomics in the Quest for Precision Endocrine Therapy of Breast Cancer [abstract]. In: Proceedings of the Thirty-Seventh Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2014 Dec 9-13; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2015;75(9 Suppl):Abstract nr ML-1.

Abstract OBJECTIVE: To determine the role of grape extract as a potential aromatase inhibitor by testing of plasma hormone levels. PROCEDURE: A six-week study was conducted involving postmenopausal women during which 94 grams of grape extract was consumed in addition to their usual diet. Plasma hormones were measured before and after treatment. RESULTS: Of the 18 women involved in the study, average age and BMI were 61.4 years and 24.4, respectively. For the hormone levels studied, the following median (IQR) percent change from baseline to 6 weeks values were found: estradiol +11.8% (-34.4%,+44.2%), p = 0.42; estrone +3.4% (-15.7%,+12.9%), p = 0.64; estrone sulfate +5.3% (-19.9%,+56.3%), p = 0.35; testosterone -1.5% (-14.7%,+10.7%), p = 0.97; androstenedione +12.6% (-17.1%, +49.1%), p = 0.15. The hormone levels did not significantly change between baseline and six weeks. Further, the changes that were observed did not tend to go in the hypothesized direction (estrogens and conjugates increased slightly, testosterone decreased slightly). Only androstenedione showed a trend toward change in the hypothesized direction. CONCLUSION: In this study, there was no evidence that plasma hormone levels are altered by 6 weeks of daily consumption of 94 grams of grape extract powder. Citation Format: Janet E. Olson, Summer V. Allen, Vera J. Suman, Tanya L. Hoskin, Celine M. Vachon, James N. Ingle. Evaluation of the aromatase inhibition potential of standardized grape extract. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 3259. doi:10.1158/1538-7445.AM2014-3259

Abstract INTRODUCTION Patient derived xenografts (PDX) may better reflect individual patient (pt) tumor biology; however, the feasibility of collecting PDX from percutaneous tumor biopsies (PTB) in the neoadjuvant setting is unknown. Furthermore, drug response phenotypes observed in PDX have not been prospectively compared to the corresponding pt clinical outcomes. METHODS The Breast Cancer Genome Guided Therapy Study (BEAUTY) is a prospective Mayo study of pts with high-risk breast cancer treated with neoadjuvant weekly paclitaxel (T) +/- trastuzumab followed by anthracycline based chemotherapy. PTB (at baseline) and residual surgical tissue (after all chemotherapy) are obtained for next generation sequencing (NGS) and PDX. Tumor biopsies (1-2 cores from 14 gauge needle) were implanted with Matrigel <1 hour of collection in the flanks of NOD-SCID or NSG mice. Low dose estradiol was supplemented in the drinking water. Primary outgrowth rate was defined as PDX tumor volume >50 mm3. Take rate was defined as development of at least 1 stably transplantable xenograft line/pt. To determine whether clinical T response assessed by MRI corresponded with in vivo T response, pretreatment PDX from 5 pts were injected into NOD-SCID mice (20 mice per pt PDX) and when tumors reached 100-200mm3, mice were randomized to no treatment vs T (20 mg/kg, ip. every 3-4 days). Two of these 5 patients had a MRI response defined as >30% decrease in longest lesion. RESULTS Pretreatment PTB from 81 unique pts were implanted in 251 mice (2-4 mice/pt). PDX outgrowth rates were 33.3% (27/81 pts) and 22 stable PDX were established (overall take rate 27.2%). Take rates were as follows: triple negative breast cancer (46%; 13/28); HER2 (27%; 6/22), Luminal B (13%; 3/22), and luminal A (0%; 0/9). Residual surgical tumor (after all treatment) from 17 pts was injected into 85 mice (average 5 mice/pt) and the initial outgrowth rate was 23% (4/17) with 3 stably transplantable lines established. PDX, derived from pretreatment PTB of 5 pts (2 responders and 3 non-responders), were assessed for in vivo T response. The size of the T treated group was significantly smaller than the no treatment group for the PDX derived from the 2 clinical responders, with complete disappearance of tumor by 18 days. In contrast, the PDX derived from the 3 clinical non-responders had no evidence for T response. CONCLUSIONS We have demonstrated the feasibility of using PTB to establish PDX in a prospective neoadjuvant clinical study and have demonstrated similar T drug response phenotypes in in the PDX as seen in the corresponding pt. These data suggest that PDX generated prospectively may be useful for biomarker validation and the development and individualization of new drug therapy. Funded by the Mayo Clinic Center for Individualized Medicine and the Mayo Clinic Cancer Center Citation Format: Jia Yu, Ping Yin, Bowen Gao, Jason P. Sinnwell, Ann M. Moyer, Daniel W. Visscher, Amy L. Conners, Travis J. Dockter, Krishna R. Kalari, Xiaojia Tang, Kevin J. Thompson, Hugues Sicotte, Douglas W. Mahoney, Steven N. Hart, Peter T. Vedell, Poulami Barman, Katie N. Jones, Sarah A. McLaughlin, John A. Copland, Alvaro Moreno Aspitia, Donald W. Northfelt, Richard J. Gray, Vera J. Suman, Jeanette E. Eckel Passow, Eric D. Wieben, James N. Ingle, Zhenkun Lou, Gianrico Farrugia, Richard Weinshilboum, Matthew P. Goetz, Judy C. Boughey, Liewei Wang. Feasibility of using percutaneous tumor biopsies from a prospective neoadjuvant breast cancer study to develop patient derived xenografts and assess in vivo chemotherapy sensitivity. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1195. doi:10.1158/1538-7445.AM2014-1195

PurposeThe effects of ovarian function suppression (OFS) on survival and patient-reported outcomes were evaluated in a phase III trial in which premenopausal women were randomly assigned to tamoxifen with or without OFS.Patients and MethodsPremenopausal women with axillary node-negative, hormone receptor–positive breast cancer tumors measuring ≤ 3 cm were randomly assigned to tamoxifen alone versus tamoxifen plus OFS; adjuvant chemotherapy was not permitted. Primary end points were disease-free survival (DFS) and overall survival (OS). Secondary end points included toxicity and patient-reported outcomes. Patient-reported outcome data included health-related quality of life, menopausal symptoms, and sexual function. These were evaluated at baseline, 6 months, 12 months, and then annually for up to 5 years after registration.ResultsIn all, 345 premenopausal women were enrolled: 171 on tamoxifen alone and 174 on tamoxifen plus OFS. With a median follow-up of 9.9 years, there was no significant difference between arms for DFS (5-year rate: 87.9% v 89.7%; log-rank P = .62) or OS (5-year rate: 95.2% v 97.6%; log-rank P = .67). Grade 3 or higher toxicity was more common in the tamoxifen plus OFS arm (22.4% v 12.3%; P = .004). Patients treated with tamoxifen plus OFS had more menopausal symptoms, lower sexual activity, and inferior health-related quality of life at 3-year follow-up (P < .01 for all). Differences diminished with further follow-up.ConclusionWhen added to tamoxifen, OFS results in more menopausal symptoms and sexual dysfunction, which contributes to inferior self-reported health-related quality of life. Because of early closure, this study is underpowered for drawing conclusions about the impact on survival when adding OFS to tamoxifen.