bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract P5-14-14: A validated clinical risk prediction model for cardiac toxicity in patients treated with antiHER2 agents
Authors: Advani Pooja P , Cornell Lauren , Li Zhuo , Ray Jordan , Sanchez Catalina , Villanueva Armando , Smith Taryn , Moreno-Aspitia Alvaro
Published: March 2020

Background: Cardiac toxicity (CT) in the form of left ventricular systolic dysfunction is a well-known complication of anti-HER2 therapy. Prior clinical trial data has suggested potential factors associated with increased risk for CT. We sought to develop a clinical risk prediction model from real world patients to better identify patients who may be at higher risk for CT. Methods: Patients treated with anti-HER2 agents at all Mayo Clinic sites from Jan 2008 to July 2015 were reviewed. Patient data including age, race, body mass index, comorbidities, smoking history, baseline ejection fraction (EF), presence of left ventricular hypertrophy (LVH), prior cancer treatments, number of anti-HER2 agents used, and cardiac medication use were recorded. Factors were compared in patients with and without development of CT. Cox regression models were used to identify univariate and multivariate predictors of CT. A risk score was then assigned based on the final multivariable model. Results: 604 patients were included in final analysis. Median follow-up 2.9 yrs; median age: 57 yr; baseline EF: 64%. One yr CT rate was 7%. Independent predictors of CT were age, baseline EF, LVH, and anthracycline use (C index=0.74). Based on model coefficient, scores of 1, 1, 2 and 3 were assigned to age>55, EF <60%, anthracycline exposure and LVH, respectively. Two random samples of 300 patients were created out of the original cohort for internal validation of the risk score model. In each, the risk score was found to be a highly significant predictor for CT with C index of 0.72 {HR 2.13 (95% CI 1.57-2.90), p <0.001} and 0.77 {HR 2.45 (95% CI 1.74-3.44), p <0.001}. Conclusions: Patients with risk factors of older age, lower baseline EF, anthracycline use and LVH are at increased risk for CT when treated with anti-HER2 agents. Using a risk prediction model at therapy initiation may enhance identification of patients who benefit from cardiology referral, closer cardiac monitoring, and/or prophylactic treatment while on anti-HER2 targeted therapy.

Table 1. Multivariable Cox regression model predicting cardiac dysfunctionParameterParameter EstimateHR (95%CI)p valueScoreAge >550.909552.48(1.27, 4.84)0.00751EF<600.634361.89(1.01, 3.53)0.04751Anthracycline Exposure1.046132.85(1.48, 5.46)0.00162Baseline LVH1.633565.12(2.04,12.85)<0.0013

Citation Format: Pooja P Advani, Lauren Cornell, Zhuo Li, Jordan Ray, Catalina Sanchez, Armando Villanueva, Taryn Smith, Alvaro Moreno-Aspitia. A validated clinical risk prediction model for cardiac toxicity in patients treated with antiHER2 agents [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P5-14-14.
Abstract P6-02-05: Clumped vs non-clumped internal enhancement patterns in linear non-mass enhancement on breast MRI
Authors: Chen Shu-Tian , Covelli James , Okamoto Satoko , Daniel Bruce , DeMartini Wendy , Ikeda Debra
Published: March 2020

Purpose To compare positive predictive values (PPVs) of clumped versus non-clumped (homogenous and heterogenous) internal enhancement on MRI detected linear non-mass enhancement (NME) on MRI-guided vacuum assisted breast biopsy (MRI-VABB). Materials and Methods With IRB approval, radiology reports were retrospectively reviewed of 598 lesions undergoing 9-gauge MRI-VABB from January 2015 to April 2018 for lesions showing linear NME, recording clumped and non-clumped internal enhancement. We reviewed the electronic medical records for MRI-guided VABB pathology, any follow up surgery and imaging and/or clinical follow-up >1 year (mean 1.7 years). The X2 test was performed for univariate analysis. Results There were 120/598 (20%) linear NME MRI-VABB lesions with clumped (52/120, 43%) vs non-clumped (68/120, 57%) internal enhancement, average size 1.8 cm (range 0.3-7.6 cm). On MRI-VABB, cancer was identified in 22/120 (18%) lesions, ductal carcinoma in situ (DCIS) was found in 18/22 (82%) and invasive cancer (3 IDC, 1 ILC) in 4 (18%). 31/120 (26%) were high-risk lesions with 3/31 (10%) high-risk lesions upgraded to DCIS at surgery, which comprising a total of 25/120 (21%) malignancies. Malignancy was found in 12/52 (23%) clumped lesions and in 13/68 (19%) of non-clumped lesions that showed heterogenous (5/13, 38%) or homogenous (8/13, 62%) internal enhancement. The PPV of linear NME with clumped internal enhancement (23.1%; 95% CI, 11.6-34.6) was not significantly different from the PPV of non-clumped linear NME (19.1%; 95% CI, 9.8-28.4) (p=0.597). The PPV of linear NME lesions <1cm (33.3%; 95% CI, 11.5-55.1) was not significantly different from the PPV of lesions ≥1cm (18.6%; 95% CI, 11.1-26.2) (p=0.157). 53/120 (44%) NME lesions were operated upon. Of the remaining 67 NME not operated upon, 2 benign findings were lost to follow up, and 65 (64 benign, 1 high-risk) showed no suspicious imaging and/or clinical features on follow up. Conclusion Linear NME showed malignancy in 21% of our series. Linear NME with clumped or non-clumped internal enhancement patterns, regardless of lesion size, should undergo MRI-VABB in appropriate clinical settings.

Citation Format: Shu-Tian Chen, James Covelli, Satoko Okamoto, Bruce Daniel, Wendy DeMartini, Debra Ikeda. Clumped vs non-clumped internal enhancement patterns in linear non-mass enhancement on breast MRI [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P6-02-05.
Abstract P6-03-07: NOTCH3 targeting inhibits ALDH1 activity and restores chemosensitivity in metastatic TNBC
Authors: D'Assoro Antonino Bonaventura
Published: March 2020

Background: Onset of metastases involves a complex multistep biological process termed the invasion-metastasis cascade, which include dissemination of cancer cells from the primary tumor to secondary organs. NOTCH signaling plays a critical role in promoting Triple Negative Breast Cancer (TNBC) metastasis. Although all four NOTCH receptors show oncogenic properties, the unique role of each of these receptors in the sequential stepwise events that typify the invasion-metastasis cascade remains elusive.

Methods: We established unique TNBC cells (TNBC-M14, -M25 and -M40), isolated from patient-derived brain metastasis xenografts (PD-BMXs). NOTCH3 genetic targeting was achieved using Lenti-vector shRNAs. Immunoblot analysis was used to assess NOTCH3 expression. ALDH1 activity was established using the ALDEOFLUOR Kit. To assess self-renewal capacity and resistance to docetaxel-based chemotherapy, TNBC cells were cultured under non-adherent conditions to form mammospheres (MPS). A publicly clinical database (http://kmplot.com) was employed to analyze NOTCH3 expression in a selected cohort of 107 lymph- node+ TNBC patients.

Results: TNBC-M14, -M25 and -M40 MPS showed NOTCH3 overexpression and higher ALDH1 activity compared to MDA-MB 231 MPS used as control. To investigate the causative role of NOTCH3 in inducing ALDH1 activity, self-renewal capacity and chemoresistance, we infected TNBC MPS with Lenti-vector shRNAs targeting NOTCH3. NOTCH3 geneting targeting induced a significant reduction of ALDH1 activity compared to TNBC MPS infected with scrambled Lenti-shRNAs. Significantly, NOTCH3 geneting targeting significantly impaired MPS formation and restored sensitivity to docetaxel. The correlation between aberrant NOTCH3 expression and poor outcome in patients with advanced TNBC was also investigated in a publicly clinical database.

Conclusions: These findings provide a compelling preclinical rationale for the design of novel clinical trials that will selectively target NOTCH3 to delay metastatic growth and to improve the clinical outcome of patients with advanced TNBC.

Citation Format: Antonino Bonaventura D'Assoro. NOTCH3 targeting inhibits ALDH1 activity and restores chemosensitivity in metastatic TNBC [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P6-03-07.
Abstract P6-03-16: Role of autophagy in CD24-mediated TNBC drug resistance
Authors: Huo Lihong , Deng Xinyu , Huang Xiang , Chang Helena R
Published: March 2020

Background: Triple-negative breast cancer (TNBC) is defined by lack of estrogen and progesterone receptors and absence of HER2 amplification. Compared with other breast cancer subtypes, TNBC is more aggressive with more frequent metastasis especially involving visceral and central nervous system. Currently, the only available standard adjuvant treatment is chemotherapy. However, mortality rate remains high despite chemotherapy. To improve treatment, it is crucial to develop novel strategies to predict and overcome drug resistance. Our pervious study showed that CD44/CD24 expressions were associated with drug sensitivity and CD44+/CD24+ TNBC was shown to be resistant to docetaxel. In this study, we aimed to investigate the regulatory mechanism involved in CD24-mediated taxane resistance in TNBC.

Methods: In this study, we used flow cytometry to determine the CD24 expressions in 7 TNBC cell lines. Western blot was used to demonstrate the levels of CD24 and LC3B-II (a marker for cellular autophagy activity) expressions in TNBC cell lines. CD24 expressions in TNBC cell lines were manipulated by target-specific shRNA and gene overexpression approaches. Cell apoptosis assay was used to determine docetaxel drug sensitivity in cells with manipulated CD24 expression. Using the same assay, autophagy inhibitors were used to further evaluate the involvement of autophagy in CD24-mediated drug resistance. To investigate the possible regulatory mechanism, autophagy related signaling pathway Akt/mTOR was studied in CD24 modified TNBC cells.

Results: In this study, the relationship between CD24 expression and autophagy activities in TNBC was evaluated. LC3B-II protein expression was used to determinate autophagy activities. We have shown that TNBC cell lines with high CD24 expressions are associated with increased LC3B-II expression. Suppression of autophagy in CD24 high TNBC cells improves drug sensitivities toward docetaxel. We further demonstrated that knocking down CD24 in TNBC cells suppressed LC3B-II expression and improved docetaxel sensitivity. In addition, gene overexpression of CD24was found to enhance docetaxel resistance in TNBC cells. Our study has also shown that docetaxel increases the activation of Akt/mTOR signaling pathway in drug-resistant TNBC cells. Knocking down CD24 increased Akt/mTOR activation, and decreased the expression of PP2A and LC3B-II in TNBC.

Conclusions: CD24 expression is associated with docetaxel sensitivity and autophagy activity in TNBC cells. Drug sensitivity of CD44+CD24+/high TNBC cells is regulated through autophagy related signaling pathway. Taken together, CD24 mediated TNBC drug resistance is at least partially through autophagy activity.

Citation Format: Lihong Huo, Xinyu Deng, Xiang Huang, Helena R Chang. Role of autophagy in CD24-mediated TNBC drug resistance [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P6-03-16.
Abstract P6-04-20: Proteogenomic analysis of estrogen modulated breast cancer metastasis
Authors: Chen Anran , Singh Purba , Kim Beom-Jun , Dobrolecki Lacey E , Welm Alana L , Lewis Michael T , Ellis Matthew J
Published: March 2020

Background: Estrogen Receptor (ER) positive breast cancer is the most common subtype (70%) and associated with the most deaths from the disease. Almost all deaths from breast cancer are caused by metastasis. While metastatic ER-positive breast cancer is a leading cause of cancer-related death, metastasis studies have largely focused on ER-negative breast cancer. A major reason for such imbalance is the lack of physiologically relevant mice models for studying ER-positive breast cancer. The patient derived xenograft (PDX) technique provides us with a powerful means to study highly clinically relevant human ER-positive breast cancer in mice, but most studies using PDX models still focus on orthotopic rather than metastatic tumor growth. Here we describe studies of the metastatic process using PDX models to more comprehensively understand the value of these PDX lines for therapeutic modelling. These findings will empower us to develop therapeutics designed to control systemic disease, not just orthotopic tumor growth.

Experimental design and methods: We have studied 14 ER positive PDX lines in ovariectomized SCID beige mice with and without estradiol supplementation. We have analyzed both orthotopic tumor and a variety of metastatic sites including liver, lung, brain and bone. Data is being generated using next-generation DNA and RNA sequencing, mass spectrometry-based proteomics. We use integrated bioinformatics pipelines to shed light on the metastatic process.

Results: We have generated macro-metastatic maps that record sites with observable metastatic nodules of each PDX line in mice. IHC of Liver, bone, brain, lung of each mouse also generated micro-metastatic maps. The most common organ of metastasis in mice is the lung. In some PDX lines, the sites of metastasis differ between groups with and without estradiol supply. The ongoing proteogenomic profiling of orthotopic and metastatic tumors reveals potential molecular drivers of metastasis in ER+ breast cancer.

Conclusion: Here, we describe an approach to the systematic investigation of the ER+ breast cancer metastasis process. This approach will allow us to identify druggable targets that may interrupt the metastatic process and/or inhibit tumor growth at metastatic sites.

Citation Format: Anran Chen, Purba Singh, Beom-Jun Kim, Lacey E Dobrolecki, Alana L Welm, Michael T Lewis, Matthew J Ellis. Proteogenomic analysis of estrogen modulated breast cancer metastasis [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P6-04-20.
Abstract P6-06-16: Resveratrol enhanced chemosensitivity by reversing macrophage polarization in breast cancer
Authors: Cheuk Isabella Wai Yin , Chen Jiawei , Siu Man Ting , Lam Sau Wing , Wang Jue , Shin Vivian Yvonne , Kwong Ava
Published: March 2020

Background: Resveratrol is a naturally occurring polyphenolic compound in Polygonum cuspidatum and is well known for its antitumor effect by targeting several cancer-related inflammatory pathways. However, limited data is available on the effect of resveratrol in the tumor microenvironment (TME). Tumor-associated macrophages (TAMs) are the most abundant leukocyte population within the tumors and are associated with poor prognosis in over 80% of breast cancer cases. This study aimed to investigate the effect of resveratrol on TAM polarization in breast cancer progression.

Methods: The antitumor effect of resveratrol was examined in MDA-MB-231(MB231), cisplatin resistance MDA-MB-231 (cisR) cells, and T47D by cell proliferation assay using MTT. Gene expressions of M1 and M2 markers in macrophages derived from THP-1 cells were examined by qPCR and immunofluorescence staining after treated with tumor-conditioned medium (TCM) with or without resveratrol (25μM). Cytokine profile of TCM was examined by Qiagen Multi-Analyte ELISArray and expression of cytokines in TCM was validated by qPCR and ELISA. The effect of resveratrol and its downstream targets on macrophage polarization were investigated by supplementing resveratrol with interferon gamma (IFN-γ, 20ng/ml) and lipopolysaccharide (LPS, 100ng/ml) for M1 macrophage polarization or IL-4 (20ng/ml) and IL-13 (20ng/ml)for M2 macrophage polarization. NOD/SCID mice were used to investigate the potential use of resveratrol in treating breast cancer and chemotherapy as complementary treatment in vivo.

Results: Our preliminary data demonstrated that resveratrol significantly reduced cell proliferation and enhanced chemosensitivity in MB231, cisR, and T47D cells. Resveratrol inhibited CD163 (M2 marker) and increased CXCL10 (M1 marker) expression. In addition, resveratrol decreased exogenous IL-6 levels in TCM, thus inhibited breast cancer cell proliferation by promoting M1/M2 macrophage polarization ratio and supressing IL-6/pSTAT3 pathway. Combined use of resveratrol and cisplatin significantly decreased tumor size in vivo.

Conclusion: Our data demonstrated that resveratrol enhanced chemosensitivity in vivo and in vitro by promoting M1/M2 macrophage polarization ratio and supressing STAT3 activation through reducing exogenous IL-6 levels. This study revealed a novel mechanism on resveratrol-mediated macrophage polarization on breast cancer progression.

Correspondence: akwong@asiabreastregistry.com

Citation Format: Isabella Wai Yin Cheuk, Jiawei Chen, Man Ting Siu, Sau Wing Lam, Jue Wang, Vivian Yvonne Shin, Ava Kwong. Resveratrol enhanced chemosensitivity by reversing macrophage polarization in breast cancer [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P6-06-16.
Abstract P6-08-14: Assessing the effectiveness of the NCCN genetic testing guidelines in identifying African American breast cancer patients with deleterious genetic mutations
Authors: Ademuyiwa Foluso O , Salyer Patricia , Ma Yinjiao , Fisher Sherri , Colditz Graham , Weilbaecher Katherine , Bierut Laura J
Published: March 2020

Purpose: Approximately 10% of breast cancers are hereditary. Identifying women at high risk for hereditary breast and ovarian cancer allows for early detection, prevention, and individualized disease management for those diagnosed with breast cancer. There is limited data about breast cancer genetic risks among African Americans (AA) as the majority of the large studies have been conducted in European Americans. We examined the distribution of deleterious genetic mutations in AA breast cancer patients, and evaluated the effectiveness of the National Comprehensive Cancer Network (NCCN) guidelines for identifying AA women at high risk for deleterious genetic mutations. Methods: AA participants with breast cancer underwent an interview regarding health and family history, and a 30-gene saliva test. Medical records were accessed to determine whether participants had received prior genetic testing as part of usual care, results of previous testing, and cancer characteristics. Results: Two hundred and fifty participants were enrolled between February 2016 and May 2018. Twenty (8.0%) had a deleterious mutation in one of the 30 genes; BRCA2 had the highest frequency (40.0%). 187 (74.8%) met eligibility for testing based on NCCN guidelines. Only 110 (58.8%) of participants eligible for genetic testing, according to guidelines, had received prior testing as part of routine care. Using the 30-gene test, we identified deleterious mutations in 17 of 187 (9.1%) of those who met NCCN criteria for testing, and three of 63 (4.8%) of those who did not meet criteria for testing nonetheless had a deleterious mutation associated with breast cancer. Conclusions: Our results indicate that a large proportion of African American breast cancer patients who meet criteria for genetic testing do not receive it as part of routine care. Even in women who do not meet testing guidelines, nearly 5% have a known deleterious mutation associated with breast cancer.

Citation Format: Foluso O Ademuyiwa, Patricia Salyer, Yinjiao Ma, Sherri Fisher, Graham Colditz, Katherine Weilbaecher, Laura J Bierut. Assessing the effectiveness of the NCCN genetic testing guidelines in identifying African American breast cancer patients with deleterious genetic mutations [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P6-08-14.
Abstract P6-08-32: Genetic variation and the role of multi-gene testing for hereditary breast cancer: A single institution experience
Authors: Lu Kit Yu , Smith Meagan , Verbiar Julia , Minor Haleigh , Lapse Jennifer , Blair Latesha , Torp Lisa
Published: March 2020

Introduction: The introduction of multi-gene testing for hereditary forms of breast cancer has changed the clinical approach to genetic testing for breast cancer patients. Recent consensus guideline now recommends genetic testing for all patients with a personal history of breast cancer and updated testing to those who have had negative germline BRCA 1 and 2 testing. This is a single institutional experience regarding the use and outcomes of multi-gene testing and updated testing.

Methods: This is a retrospective analysis of germline multi-gene testing for breast cancer patients at our institution. Information on tumor histology, personal and family history of cancer, age at diagnosis, and genetic testing information was obtained through records review.

Results: Between January 1, 2015 and December 31, 2018, 1568 breast cancer patients were diagnosed or treated at our institution. Of those, 26% of the patients had genetic results (age range 23-87; median age 52; <1% Male; 88% non-Hispanic whites, 8% blacks, 2% Asians, 2% Hispanics). Eight percent of the patients were found to carry a pathogenic variant that the NCCN guidelines designated as sufficient evidence to have an increased risk for breast cancer. Of those, only 3.4% were BRCA 1 and 2 mutations. The prevalent pathogenic variants found in multi-gene testing were BRCA 1/ 2 (3.4%), CHEK2 (2.2%), PALB2 (1%), TP53 (1%), PMS2 (1%), MYTYH (0.74%), FANCC (0.25%), ATM (0.25%), MSH2 (0.25%), MSH6 (0.25%), NBN (0.25%), and RAD51C (0.25%). Fifteen patients had initial testing looking only for the presence of germline BRCA 1 and 2 mutations. Of those, updated expanded testing identified an additional two patients who carried a pathogenic variant that was previously unidentified.

Conclusion: Multi-gene testing and expanded panel testing of all breast cancer patients could increase the detection of pathogenic variants and may have a potential clinical impact for patients and their family. Further understanding of genetic patterns and variation in multi-gene testing is needed. Increasing public awareness and decreasing the cost of genetic testing are also important to improve the rates of multi-gene testing.

Citation Format: Kit Yu Lu, Meagan Smith, Julia Verbiar, Haleigh Minor, Jennifer Lapse, Latesha Blair, Lisa Torp. Genetic variation and the role of multi-gene testing for hereditary breast cancer: A single institution experience [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P6-08-32.
Abstract P6-08-36: Uptake of preventive surgeries in a prospective cohort of BRCA1/2 healthy women
Authors: Nejo Priscila , Bexiga Catarina , Fragoso S. , Mayer A , Santos S , Louro P , Luis A , Moura C , Clara Ana , Vaz Fatima
Published: March 2020

PURPOSE

Previous studies referred to uptake of preventive surgeries (PS) in BRCA1/2 healthy carriers in ages older than recommended (35yrs). Since our population has a higher prevalence of BRCA2 mutations (usually associated with an older age at Breast Cancer diagnosis) we proposed to study ages and type of preventive surgeries uptaken by BRCA1/2 women included in prospective follow up.

PATIENTS AND METHODS

Review of all healthy (without a previous cancer diagnosis) BRCA1/2 carriers included in our program from January 2000 to June 2019. Follow-up started after genetic testing. Men were excluded from this analysis.

RESULTS

A total of 5504 cases (4021 index, 1483 relatives) consented for BRCA1/2 testing. We identified 238 healthy BRCA1/2 carriers (BRCA2:158 (66.4%) vs BRCA1 80 (33.6%). Median age at genetic diagnosis was 38.9 yrs (16-78). With a median follow up of 4yrs, bilateral adnexectomy (BA) was the most frequent PS observed (45 BRCA2 and 28 BRCA1 cases) with 15/45 % and 6/28% undergoing BA and bilateral mastectomy (BM) simultaneously. Bilateral mastectomy was uptaken by 14% BRCA2 women and 10% BRCA1 women. Median ages for PS were: BRCA2-AB: 47,4 (28-71), BRCA1-AB: 46.7 (37-59); BRCA2-BM: 36.6 (31-52) and BRCA1-BM:42.5 (30-55). Isolated BM was observed in 7 BRCA2 cases and 2 BRCA1 cases. Most of women submitted to BA, also underwent total hysterectomy (HT): 65% for BRCA2 and 61% BRCA1. Most cases (88% non-adherent) adhere to radiological surveillance, 111/238 with annual breast S MRI and mammography. All pts submitted to BM are prescribed at least one breast MRI to check for remaining breast tissue.

CONCLUSION

Our data reveal that even if, in general, BRCA1/2 women uptake preventive surgeries at a later age that recommended, we observed a strong adherence to radiological (most with breast MRI) surveillance. BA is the PS most frequently observed but, surprisingly for healthy women, most cases also underwent TH. BRCA2 healthy women uptaken bilateral mastectomy at an earlier age than BRCA1 women. It´s possible that BRCA1 women, when deciding for BM also decided for BA.

Citation Format: Priscila Nejo, Catarina Bexiga, S. Fragoso, A Mayer, S Santos, P Louro, A Luis, C Moura, Ana Clara, Fatima Vaz. Uptake of preventive surgeries in a prospective cohort of BRCA1/2 healthy women [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P6-08-36.
Abstract P6-10-29: Circular RNAs in exosomes derived from breast cancer: Promising biomarkers for diagnosis and prognosis of triple negative breast cancer (TNBC)
Authors: Yang Sujin , Tang Jinhai
Published: March 2020

Background: With the recent development of transcriptome sequencing technology, circular RNAs (circRNAs) have attracted extensive attention from researchers. Exosomes are usually recognized as a type of membrane vesicles containing RNA (mRNA, miRNA, circRNAs and other non-coding RNAs), proteins and lipids, and may be used as promising biomarkers for disease diagnosis. Unfortunately, circRNAs still remains many action mechanisms of circRNAs cannot be understood completely in the process of tumor development. The study aims to explore novel circRNAs and their potential functions in the treatment and progonsis of TNBC.Materials & methods: A combinative strategy of RNA-sequencing (RNA-seq) technique, RT-qPCR and bioinformatic analysis was employed to unearth the potential mechanism of differential circRNAs in serum-exosomes (n=20) and tissues (n=20) from TNBC patients.Results: Combination of the two datasets from differential circRNAs in serum-exosomes and tissues, the result showed that three circRNAs (has-circRNA-LPXN, has-circRNA-NUFIP2 and has-circRNA-HSDL2) were significantly differentially-expressed in both datasets. RT-qPCR used to verify these three circRNAs in cells and serum-exosomes also found has-circRNA-LPXN was down-regulated and has-circRNA-HSDL2 was up-regulated, which was valuable for breast cancer diagnosis by analyzing these circRNAs in serum-exosomes from BCa patients compared with healthy people.

Conclusion: The expression levels of has-circRNA-LPXN and has-circRNA-HSDL2 were found significantly different both in serum-exosomes and tissues of TNBC and these circRNAs might function as competing endogenous RNAs and play vital roles in the development of TNBC. More importantly, we constructed two circRNAs-miRNAs networks and provided new insight into prognosis and therapy of TNBC from circRNAs in the serum-exosomes.

Citation Format: Sujin Yang, Jinhai Tang. Circular RNAs in exosomes derived from breast cancer: Promising biomarkers for diagnosis and prognosis of triple negative breast cancer (TNBC) [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P6-10-29.
Abstract PD2-03: CDK4/6 inhibitor-resistant ER+ breast cancer cell lines are hypersensitive to TTK inhibition
Authors: Bretones Isabel Soria , Thu Kelsie L , Silvester Jennifer , Kiarash Reza , Fletcher Graham C , Cruickshank Jennifer , Bray Mark R , Mak Tak W , Cescon David W
Published: March 2020

Inhibitors of cyclin-dependent kinases 4 and 6 (CDK4/6i), in combination with hormonal therapies, have become standard of care for the treatment of estrogen receptor-positive (ER+)/HER2-negative metastatic breast cancer. Despite demonstrating significant improvements in progression-free survival, acquired resistance to these inhibitors invariably develops. Recent analyses of clinical samples have identified emergent genomic alterations conferring acquired resistance to CDK4/6i, and begin to define the biology of this new clinical entity. Discovery of vulnerabilities of CDK4/6i-resistant tumours is imperative to improve the survival of this group of patients. We modeled CDK4/6i resistance in ER+ breast cancer cell lines using two complementary approaches: (1) spontaneous development of resistance upon continuous exposure to the palbociclib for 6-9 months, and (2) genetic engineering of RB1 loss of function. In both cases, palbociclib resistance was confirmed by colony formation and cell proliferation assays. To identify potential therapeutic strategies for CDK4/6i-resistant cells, we tested the in vitro activity of novel cell cycle inhibitors using sulforhodamine B (SRB) cytotoxicity assays. CFI-402257, a selective TTK inhibitor now in Phase I testing, induced significantly increased cytotoxicity in different CDK4/6i-resistant models compared to parental cell lines, including but not exclusively those with RB1 loss. CFI-402257 treatment caused defects in cell cycle progression and increased DNA damage and genomic instability in CDK4/6i-resistant cells, while these effects were mild in parental, CDK4/6i-sensitive cell lines. In some cases, these phenotypes were accompanied by an increase in apoptotic signaling. Analysis of the molecular determinants of these effects are being evaluated (additional results will be presented). In xenografts derived from MCF7 cells, CFI-402257 treatment completely abrogated the growth of RB1-KO tumours and had a much less pronounced effect on wild-type tumours. In summary, our results nominate the TTK inhibitor CFI-402257 as a promising therapeutic strategy for breast cancer patients who progress after CDK4/6 inhibition. A clinical trial testing this strategy is being launched.

Citation Format: Isabel Soria Bretones, Kelsie L Thu, Jennifer Silvester, Reza Kiarash, Graham C Fletcher, Jennifer Cruickshank, Mark R Bray, Tak W Mak, David W Cescon. CDK4/6 inhibitor-resistant ER+ breast cancer cell lines are hypersensitive to TTK inhibition [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr PD2-03.
Abstract PD6-5: The association between radiotherapy and contralateral breast cancer risk in young BRCA1/2-associated breast cancer patients
Authors: van Barele Mark , Akdeniz Delal , Heemskerk-Gerritsen Bernadette AM , Baaijens Margreet HA , Sattler Margriet GA , Schmidt Marjanka K , Jager Agnes , Hooning Maartje J ,   HEBON collaborators
Published: March 2020

Background: Long-term side-effects of cancer treatment are becoming more important as survival improves. Secondary cancer is a concern after radiotherapy, especially for patients treated at a young age. Since the BRCA1/2 genes play an essential role in DNA-repair, carriers of BRCA1/2 mutations are possibly more susceptible to the harmful side-effects of radiotherapy.

Aim: To investigate whether breast cancer (BC) patients with a BRCA1/2 mutation are at increased risk of developing contralateral breast cancer (CBC) after treatment with adjuvant radiotherapy at a young age.

Methods: BRCA1/2 mutation carriers previously diagnosed with BC were selected from the Dutch national HEBON study. We used a left-truncated Cox proportional hazards model to estimate the association between radiotherapy (yes/no) and CBC risk, stratifying for age (<40 vs ≥40) and censoring for contralateral prophylactic mastectomy.

Results: Median follow-up was 10.1 years for the radiotherapy group (n=901), and 9.3 years for the non-radiotherapy group (n=609) (p=0.072). Median age at BC diagnosis and the distribution of BRCA1 and BRCA2 carriers was similar for both groups. Radiotherapy overall was not significantly associated with a higher risk of CBC (adjusted hazard ratio (HR) 1.31; 95%CI 0.91-1.89, n=1510). Six-hundred and forty patients were less than 40 years of age at BC diagnosis. Those treated with radiotherapy (n=366) had a higher stage and less often underwent mastectomy and prophylactic contralateral mastectomy.

Stratifying by age at diagnosis yielded a HR of 1.66 (95%CI 0.93-2.95) for age<40 and a HR of 1.01 (95%CI 0.64-1.61) for age≥ 40.

Conclusion: BRCA1/2 mutation carriers irradiated for primary BC under the age of 40 may have an increased risk of developing CBC.

Citation Format: Mark van Barele, Delal Akdeniz, Bernadette AM Heemskerk-Gerritsen, Margreet HA Baaijens, Margriet GA Sattler, Marjanka K Schmidt, Agnes Jager, Maartje J Hooning, HEBON collaborators. The association between radiotherapy and contralateral breast cancer risk in young BRCA1/2-associated breast cancer patients [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr PD6-5.
Abstract PD8-08: Characterization of spatial and temporal heterogeneity of ER positive metastatic breast cancer using serial biopsies
Authors: Allen Read K. , Pinto Christopher J. , Fitzgerald Donna M. , Huynh Tiffany G. , Chen Christopher T. , Juric Dejan
Published: March 2020

Background: Metastatic breast cancer is characterized by a remarkable level of temporal and spatial heterogeneity. Management decisions based on a single tissue biopsy are therefore inherently limited by sampling bias and by dynamic changes in the receptor status and the mutational profile of the tumor. Methods: We characterized 41 serially enrolled patients on the tissue collection protocol DFHCC 13-416, who had ER+/HER2- breast cancer at the time of diagnosis of early stage disease. Results: 36 out of 41 patients (87.8%) had at least one biopsy in the metastatic setting. The number of biopsies in the metastatic setting ranged from one to seven. Two most frequently biopsied sites were liver (24.4%) and recurrent breast lesions (22.0%). Six out of 41 patients (14.6%) developed ER loss over the course of treatment. Estrogen receptor status conversions were noted in both the liver and in the recurrent breast lesions. PR loss was far more common, noted in 24 out of 41 patients (58.5%). Nine of these patients (21.9%) were PR negative at the time of diagnosis and an additional 15 patients (36.6%) lost PR expression during the course of their therapy. Median time to the loss of ER expression was 6.83 years from the initial diagnosis, while the median time to the loss of PR expression was 4.97 years, consistent with sequential decrease in ER dependence, resulting in loss of PR expression and increased dependence on other survival pathways. Genomic and transcriptomic profiling of all serially collected tissues with reconstruction of phylogenetic trees is ongoing and will be presented at the meeting. Conclusions: Compared to previously published reports, high proportion of patients in this cohort had their metastatic disease confirmed and subsequently followed by serial biopsies. In majority of patients, receptor status changes follow a predictable pattern starting with loss of PR expression, followed by complete loss of ER expression. Concomitant changes in the mutation status of both ER and other co-mutated genes, as well as any associated transcriptomic changes may shed light into new interdependencies and vulnerabilities associated with these dynamic receptor status changes.

Citation Format: Read K. Allen, Christopher J. Pinto, Donna M. Fitzgerald, Tiffany G. Huynh, Christopher T. Chen, Dejan Juric. Characterization of spatial and temporal heterogeneity of ER positive metastatic breast cancer using serial biopsies [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr PD8-08.
Abstract PD8-10: Regulation of breast tumor metastasis by the dynamic interaction between the TMEM doorway macrophage, tumor and endothelial cells
Authors: Surve Chinmay , Harney Allison S. , Chen Mary , Wang Yarong , Ye Xianjun , Lin Yu , Sharma Ved , Stanley Richard , Oktay Maja H. , Condeelis John S.
Published: March 2020

Tumor cell intravasation is an essential step in the metastatic cascade, but its exact mechanism is not completely understood. We have previously shown that the direct physical association of a tumor cell over-expressing Mena, a Tie2hi/Vegfhi macrophage and an endothelial cell, creates a micro-anatomic doorway called “tumor microenvironment of metastasis” (TMEM). TMEM are responsible for cancer cell intravasation and dissemination to distant sites. The density of TMEM doorways is a clinically validated prognostic marker of distant metastasis in breast cancer patients. Although we know that TMEM doorways create increased localized vascular permeability which cancer cells utilize to intravasate, the precise molecular mechanisms relating TMEM-doorway function and intravasation has not been elucidated. Active TMEM doorways are found in pre-invasive and invasive ductal breast carcinoma as well as in metastatic foci in lymph nodes and lungs, indicating that TMEM-mediated cancer cell dissemination occurs not only at the primary tumor site but also at metastatic sites, which may perpetuate metastatic dissemination even after removal of the primary tumor. Thus it is essential to understand the exact molecular mechanism of TMEM-doorway function so that specific targeted therapies can be developed to intercept systemic cancer cell dissemination. We outline here the exact molecular mechanism of TMEM-doorway functions. TMEM doorway endothelial cell-secreted Ang2 (a Tie2 ligand) stimulates VEGF expression and production by the Tie2hi TMEM macrophage. Subsequently, the TMEM doorway tumor cell- secreted CSF1 stimulates local secretion of VEGF from the Tie2hi TMEM macrophages, leading to dissociation of endothelial adherens and tight junctions near TMEM and cancer cell intravasation. In addition, we show that acute blockage of CSF1R and Tie2-Ang2 signaling by inhibitors and blocking antibodies both in vitro and in mammary tumors leads to decreased macrophage VEGF production and secretion, decreased tumor cell trans-endothelial migration, and decreased TMEM-dependent vascular permeability, tumor cell dissemination and circulating tumor cells. This is the first description of the molecular mechanisms regulating TMEM doorway function and thus represents a major step in defining new biomarkers and targets for the treatment of metastatic tumors.

Citation Format: Chinmay Surve, Allison S. Harney, Mary Chen, Yarong Wang, Xianjun Ye, Yu Lin, Ved Sharma, Richard Stanley, Maja H. Oktay, John S. Condeelis. Regulation of breast tumor metastasis by the dynamic interaction between the TMEM doorway macrophage, tumor and endothelial cells [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr PD8-10.
Abstract B103: Molecular heterogeneity of gastric cancer explained by methylation-driven key regulators
Authors: Yoo Seungyeul , Chen Quan , Wang Li , Wang Wenhui , Chakravarthy Ankur , Busuttil Rita , Boussioutas Alex , Fenton Tim R. , Zhang Jiangwen , Fan Xiaodan , Leung Seut-Yi , Zhu Jun
Published: March 2020

Gastric cancer (GC) is a heterogeneous disease in which diverse genetic, genomic, and epigenetic alterations can accumulate in different molecular and histologic subtypes. Tumor microenvironment (TME) also contributes to the heterogeneity of GC. To investigate what molecular features of tumor cells drive GC heterogeneity, we developed an integrative causal model, called Integrative Sequential Causality Test (ISCT), to identify key regulators of GC by integrating DNA methylation, copy number variation, and transcriptomic data. Applying ISCT to three GC cohorts that contain methylation, CNV, and gene expression data, 11 common methylation-driven key regulators were identified: ADHFE1, CDO1, CRYAB, FSTL1, GTP, PKP3, PTPRCAP, RAB25, RHOH, SFN, and SORD. Based on these 11 genes, gastric tumors resolved into three groups that were associated with known molecular subtypes, Lauren classification, tumor stage, and patient survival, suggesting significance of the methylation-driven key regulators in molecular and histologic heterogeneity of GC. We also investigated the relationship between TME and the methylation-driven key regulators and showed that both immune/stromal proportions in TME and tumor cell genomics variations contributed to expression variations of the methylation-driven key regulators. Especially, FSTL1, significantly associated with patient survival and tumor progression as well as stromal proportion in TME, was expressed at high level in both stromal and cancer cells, indicating its potential role in mediating tumor-stroma interactions. In summary, this study suggests that genetic, genomic, and epigenetic alterations as well as their interactions with TME contribute to heterogeneity of GC.

Citation Format: Seungyeul Yoo, Quan Chen, Li Wang, Wenhui Wang, Ankur Chakravarthy, Rita Busuttil, Alex Boussioutas, Tim R. Fenton, Jiangwen Zhang, Xiaodan Fan, Seut-Yi Leung, Jun Zhu. Molecular heterogeneity of gastric cancer explained by methylation-driven key regulators [abstract]. In: Proceedings of the AACR Special Conference on Tumor Immunology and Immunotherapy; 2019 Nov 17-20; Boston, MA. Philadelphia (PA): AACR; Cancer Immunol Res 2020;8(3 Suppl):Abstract nr B103.
Abstract B20: Repurposing of fenofibrate to prevent and treat PM-induced pulmonary fibroblast-mediated inflammation: Mechanism involved in SIRT1-SREBP1-PIR/NLRP3 inflammasome axis
Authors: Tien Chia-Ping , Chang Yu-Chan , Hung Shih-Chieh , Hsiao Michael
Published: March 2020

Particulate matter (PM) has been shown to have strong link with a variety of human morbidity and mortality. World Health Organization (WHO) recognizes air pollution as an invisible killer responsible for around 7 million global deaths per year, including 43% from chronic obstructive pulmonary disease (COPD), 29% from lung cancer, 25% from heart diseases, 24% from stroke, and 24% from pneumonia. Cardiopulmonary disease is considered as the leading PM-induced complication. The main mechanism involved in PM-induced cardiopulmonary disease is through upregulation of redox-sensitive signaling pathways, mediated by nuclear factor kappa B (NF-κB). We analyzed transcriptomics data by microarray chips in human pulmonary fibroblasts (HPF) after being treated by different doses of PM, and our result identified sterol regulatory element-binding protein 1 (SREBP1) as the top 1 transcription factor activated after PM exposure in HPF. Our analysis showed that Pirin (PIR), an iron-dependent redox regulator of NF-κB, was the most significantly and plausible transcriptional targets of SREBP1. Additionally, SREBP1, directly deacetylated and inhibited by Sirtuin 1 (SIRT1), increased the expression of inflammasome markers, e.g., NACHT, LRR and PYD domains containing protein 3 (NLPR3), Apoptosis-Associated Speck-Like Protein Containing CARD (ASC), and interleukin-1β (IL-1β), were documented. Our results further showed PM-induced inflammation could be reversed by inhibitors of SIRT1, SREBF1, and PIR. We concluded that SIRT1-SREBP1-PIR/NLRP3 inflammasome axis may play a key role in PM-induced sequel and may present new targets. Fenofibrate, clinically prescribed for dyslipidemia, prevented atrial fibrillation rabbits from atrial metabolic remodeling through the SIRT1-SREBP1 pathway. Moreover, in vivo fenofibrate was reported to regulate hyperglycemia-induced metabolic memory and reduce the inflammatory response via SIRT1-dependent suppression of NF-κB. On the basis of previous work and this study, we may repurpose fenofibrate as an anti-PM drug to prevent and treat PM-induced cardiopulmonary disease, which can be used in combination with COPD, heart disease, or anticancer medicines in future research.

Citation Format: Chia-Ping Tien, Yu-Chan Chang, Shih-Chieh Hung, Michael Hsiao. Repurposing of fenofibrate to prevent and treat PM-induced pulmonary fibroblast-mediated inflammation: Mechanism involved in SIRT1-SREBP1-PIR/NLRP3 inflammasome axis [abstract]. In: Proceedings of the AACR Special Conference on Tumor Immunology and Immunotherapy; 2019 Nov 17-20; Boston, MA. Philadelphia (PA): AACR; Cancer Immunol Res 2020;8(3 Suppl):Abstract nr B20.
Abstract B79: PET CT might be better than CT scan when evaluating immune checkpoint inhibitor response
Authors: Choi JuWhan , Shin Hyun Seock , Oh Jee Youn , Lee Young Seok , Min Kyung Hoon , Shim Jae Jeong , Lee Sung Yong
Published: March 2020

Background: Immune checkpoint inhibitors (ICIs) are changing the paradigm of non-small cell lung cancer (NSCLC) treatment. However, in assessing tumor response, hyperprogression or pseudoprogression can cause difficulties in accurately identifying therapeutic response. We analyzed the usefulness of positron emission tomography-computed tomography (PET-CT) in treatment response assessment of ICI.

Methods: We retrospectively analyzed 12 advanced NSCLC patients who used ICI (pembrolizumab) as the first-line treatment. Chest CT was taken at two cycle intervals, and PET-CT was taken before ICI treatment and after the 2nd cycle. Comparison of response evaluation of tumor size was analyzed using chest CT, and the standardized uptake value (SUV) max was compared using PET-CT.

Results: Among 13 patients, eleven cases were male and one case was female. The mean age was 66.2 ± 6.7 years. Seven patients were treated with pembrolizumab monotherapy, and five patients were treated with pembrolizumab plus cytotoxic chemotherapy. 8 of the 12 patients received more than four cycles of treatment. The mean tumor size before treatment was 7.3 ± 3.3 cm and after treatment was 6.2 ± 3.7 cm, which was not statistically significant (P-value = 0.099). The mean SUV maximum value before treatment was 10.1 ± 3.3 and after treatment was 5.8 ± 2.6 cm, which was statistically significant (P-value = 0.004). SUV max showed a more pronounced trend than tumor size. Two of the five patients who showed stable disease in the first response assessment showed a partial response in the second response assessment. The mean SUV max value was decreased at 58.2% in these two patients.

Conclusion: In evaluating the response of ICIs, PET-CT showed more predictive change compared to CT scan. In predicting the therapeutic response of an ICIs, measuring the metabolic activity of a tumor may be more important than comparing tumor size. PET CT may be a useful tool in evaluating the treatment response of ICI.

Citation Format: JuWhan Choi, Hyun Seock Shin, Jee Youn Oh, Young Seok Lee, Kyung Hoon Min, Jae Jeong Shim, Sung Yong Lee. PET CT might be better than CT scan when evaluating immune checkpoint inhibitor response [abstract]. In: Proceedings of the AACR Special Conference on Tumor Immunology and Immunotherapy; 2019 Nov 17-20; Boston, MA. Philadelphia (PA): AACR; Cancer Immunol Res 2020;8(3 Suppl):Abstract nr B79.