يعرض 1 - 5 نتائج من 5 نتيجة بحث عن '"Gregory Kirkner"', وقت الاستعلام: 0.66s تنقيح النتائج
  1. 1
    دورية أكاديمية

    المصدر: npj Breast Cancer, Vol 10, Iss 1, Pp 1-12 (2024)

    الوصف: Abstract The ESR1 ligand binding domain activating mutations are the most prevalent genetic mechanism of acquired endocrine resistance in metastatic hormone receptor-positive breast cancer. These mutations confer endocrine resistance that remains estrogen receptor (ER) dependent. We hypothesized that in the presence of the ER mutations, continued ER blockade with endocrine therapies that target mutant ER is essential for tumor suppression even with chemotherapy treatment. Here, we conducted comprehensive pre-clinical in vitro and in vivo experiments testing the efficacy of adding fulvestrant to fluorouracil (5FU) and the 5FU pro-drug, capecitabine, in models of wild-type (WT) and mutant ER. Our findings revealed that while this combination had an additive effect in the presence of WT-ER, in the presence of the Y537S ER mutation there was synergy. Notably, these effects were not seen with the combination of 5FU and selective estrogen receptor modulators, such as tamoxifen, or in the absence of intact P53. Likewise, in a patient-derived xenograft (PDX) harboring a Y537S ER mutation the addition of fulvestrant to capecitabine potentiated tumor suppression. Moreover, multiplex immunofluorescence revealed that this effect was due to decreased cell proliferation in all cells expressing ER and was not dependent on the degree of ER expression. Taken together, these results support the clinical investigation of the combination of ER antagonists with capecitabine in patients with metastatic hormone receptor-positive breast cancer who have experienced progression on endocrine therapy and targeted therapies, particularly in the presence of an ESR1 activating mutation.

    وصف الملف: electronic resource

  2. 2
    دورية أكاديمية

    المصدر: Nature Communications, Vol 14, Iss 1, Pp 1-10 (2023)

    مصطلحات موضوعية: Science

    الوصف: Abstract The molecular underpinnings of HER2-low and HER2-0 (IHC 0) breast tumors remain poorly defined. Using genomic findings from 1039 patients with HER2-negative metastatic breast cancer undergoing next-generation sequencing from 7/2013-12/2020, we compare results between HER2-low (n = 487, 47%) and HER2-0 tumors (n = 552, 53%). A significantly higher number of ERBB2 alleles (median copy count: 2.05) are observed among HER2-low tumors compared to HER2-0 (median copy count: 1.79; P = 2.36e-6), with HER2-0 tumors harboring a higher rate of ERBB2 hemideletions (31.1% vs. 14.5%). No other genomic alteration reaches significance after accounting for multiple hypothesis testing, and no significant differences in tumor mutational burden are observed between HER2-low and HER2-0 tumors (median: 7.26 mutations/megabase vs. 7.60 mutations/megabase, p = 0.24). Here, we show that the genomic landscape of HER2-low and HER2-0 tumors does not differ significantly, apart from a higher ERBB2 copy count among HER2-low tumors, and a higher rate of ERBB2 hemideletions in HER2-0 tumors.

    وصف الملف: electronic resource

  3. 3
    دورية أكاديمية
  4. 4

    المصدر: Cancer Research. 83:HER2-05

    مصطلحات موضوعية: Cancer Research, Oncology

    الوصف: Background: About half of all breast cancers exhibit low HER2 expression. Despite lack of ERBB2 amplification, HER2-low tumors respond to trastuzumab deruxtecan (T-DXd), leading to the NCCN recommendation of T-DXd both for patients with HER2+ and HER2-low metastatic breast cancer (MBC). It remains however unclear if HER2-low represents a distinct molecular entity, as compared to HER2-0 MBC. Here, we compare the genomic landscape of HER2-low versus HER2-0 breast cancers in a large, single institution cohort. Methods: We identified consecutive patients with MBC seen at Dana-Farber Cancer Institute between 07/2013 and 12/2020. Patients were included if they had HER2-negative MBC per ASCO/CAP Guidelines and had undergone next generation sequencing (NGS) testing with a targeted, tumor-only platform (OncoPanel). Based on the HER2 status of the specimen tested by NGS, patients were divided into 2 groups: (i) HER2-low if immunohistochemistry (IHC) 1+ or 2+ non-amplified, or (ii) HER2-0 if IHC 0. Mutations of interest detected on NGS were classified as oncogenic using the OncoKB tool and additional annotation. Genomic profiles of HER2-low and HER2-0 tumors were compared using Chi-Square and Kruskal-Wallis tests. To determine genomic event enrichment between the two HER2 groups, logistic regression models were used, accounting for background rate and estrogen receptor (ER) expression. ERBB2 copy counts were calculated for tumors with recorded histology-estimated purities and copy-number segmentation using a simple model of allelic gain/loss. Results: Among 1847 patients with HER2-negative MBC, 1043 underwent NGS testing on a HER2-low (n=489, 47%) or HER2-0 sample (n=554, 53%). Most samples were metastatic (71%, n=743) while 29% (n=300) were from primary tumors. 73% had ductal histology, 13% were lobular and 14% had mixed or other histology. ER expression was enriched among HER2-low vs. HER2-0 tumors (76% vs. 60%; p< 0.001). Focusing on the most commonly occurring genetic mutations, no major differences were observed in HER2-low vs. HER2-0 tumors, after correcting for ER status (Table 1). Among all mutational events, any mutation in MPL, CYLD, and MAP3K and oncogenic mutations in TP53 and NF1 were more common in HER2-0, while any mutation in MTOR, RAD21, DNMT3A, and PDGFRA were enriched in HER2-low patients, when controlling for ER status and background mutational rate (p< 0.05). However, no mutation reached significance after accounting for multiple hypothesis testing. Similarly, no deep deletion or high amplification CNV events reached significance for either group. Analysis of tumor mutational burden in HER2-low vs. HER-0 tumors revealed no significant differences (median: 7.26 muts/Mb vs. 7.60 muts/Mb, p=1.00), including when accounting for ER status. Finally, among tumors with sufficient tumor purity for ERBB2 copy count analysis (n=374 and 419 for HER2-low and HER2-0, respectively), HER2-low tumors had a significantly higher number of ERBB2 alleles as compared to HER2-0 (< 2 copies, 15.0% vs. 30.9%, 2 copies 67.4% vs. 60.5%, and >2 copies, 17.6% vs. 8.6%; p< 0.001 by Kruskal-Wallis). Conclusions: To our knowledge, this is the largest comprehensive genomic analysis of HER2-low MBC to date. In our cohort of patients with HER2-negative MBC, the genomic landscape of HER2-low and HER2-0 tumors did not differ significantly, apart from a higher number of ERBB2 alleles. These data further support the notion that HER2-low, as currently defined, is not a distinct molecular subtype of breast cancer. Citation Format: Paolo Tarantino, Hersh V. Gupta, Melissa E. Hughes, Janet L. Files, Sarah Strauss, Gregory Kirkner, Anne-Marie Feeney, Yvonne Y. Li, Ana C. Garrido-Castro, Romualdo Barroso-Sousa, Brittany Bychkovsky, Laura MacConaill, Neal Lindeman, Bruce Johnson, Matthew Meyerson, Sheheryar Kabraji, Rinath Jeselsohn, Xintao Qiu, Rong Li, Henry W. Long, Eric Winer, Deborah A. Dillon, Giuseppe Curigliano, Andrew Cherniack, Sara Tolaney, Nancy U. Lin. HER2-05 Comprehensive genomic characterization of HER2-low breast cancer [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr HER2-05.

  5. 5

    المصدر: Cancer Research. 83:P5-14

    مصطلحات موضوعية: Cancer Research, Oncology

    الوصف: Background. Patients (pts) who develop MBC at older ages are underrepresented in clinical trials, are less likely to be included in comprehensive biomarker characterization studies, and experience worse breast cancer-specific survival than their younger counterparts. Elucidating genomic underpinnings of MBC and possible therapeutic targets for older breast cancer patients are critical priorities. Methods. We identified pts age >70 years at MBC diagnosis and a younger cohort (ages 50-69; age < 50), who were treated for MBC at a single center and who had their metastatic (or if not available, the primary) tumor, assessed by a targeted, tumor-only next generation sequencing (NGS) platform (OncoPanel) between 2013-2020. The NGS panel included mutations, copy number variation, tumor mutational burden (TMB), and hypermutation (HM) status, with mutations classified as oncogenic using the OncoKB tool and additional annotation. Copy number events were selected as being “oncogenic” if a high amplification was called for an oncogene or a deep deletion for a tumor suppressor. We compared findings for older (age >70) vs. younger (age < 50 and ages 50-69) MBC pts using Chi-Square and Kruskal-Wallis tests. To determine genomic event enrichment, logistic regression (LR) models were used, controlling for age (continuous), background rate, and tumor subtype (those with unknown subtype [n=27] were excluded from models). False discovery rate (FDR) was used to correct for multiple hypothesis testing. Results. The final analytic cohort included 2,380 pts. The median age at MBC diagnosis was 54.1 years overall (range 18.5- 91.9) and 73.6 years for those age >70. A total of 137 metastatic and 76 primary tumors were sequenced in pts age >70; in those age < 70, 1383 metastatic and 784 primary tumors were sequenced (for age < 50 [n=857] and 50-69 [n=1310]). Older pts were more likely to present with HR+/HER2- tumors (70.9% v. 62.4% v. 52.4%), and less likely to present with HER2+ (9.4% v. 14.4% v. 22.8%) or triple-negative breast cancer (TNBC) (18.8% v. 21.9% vs. 24.0%) at MBC diagnosis (listed >70, 50-69, < 50; P=1e-7). Older pts had higher average TMB vs. younger pts (9.57 in pts > 70, 8.56 in ages 50-69, 7.34 in ages < 50; P=3.5e-5). This was due to older pts having a higher incidence of hypermutation status as defined as TMB >10: 26.3% in age >70, 23.2% in ages 50-69, 16.8% in age < 50. Using q=0.1 as the threshold of significance, the presence of CDH1, PIK3CA, MAP3K1, TET2, and AKT oncogenic mutations were also enriched in older pts, while the presence of oncogenic GATA3, BRCA2, and TP53 mutations, as well as any mutation in BRCA1 were enriched in younger pts (too few oncogenic BRCA1 mutations were present for accurate modeling). The frequency of oncogenic PIK3CA mutations in HR+/HER2- tumors was highest in the oldest pts (44.4% in pts age >70 v. 31.6% in age 50-69 v. 26.7% in age < 50). Of pts who had oncogenic BRCA1/2 mutations identified on tumor-only NGS testing and underwent clinical germline testing (n=7 v. 60 v. 67, oldest to youngest), older pts had the lowest incidence of germline BRCA pathogenic variants (14.3% vs. 47.2.% vs. 67.2%; p=0.01); most BRCA mutations identified on NGS testing in older patients were considered likely somatic. When assessing enrichment in copy number events, ERBB2, RAD21, and BRIP1 amplifications were all significantly less frequent in older pts (q< 0.1), even when accounting for tumor subtype. Conclusions. In a large cohort of pts with MBC, the mutational and copy number landscape for older pts differs from that in younger pts, even after controlling for tumor subtype. Key actionable findings include a higher proportion of high TMB and PIK3CA-mutated tumors, emphasizing the importance of genomic profile testing in this pt population and further exploration of efficacy and tolerability of relevant therapies in those age >70 years. Citation Format: Hersh V. Gupta, Rachel Freedman, Melissa E. Hughes, Yvonne Y. Li, Gregory Kirkner, Janet L. Files, Sarah Strauss, Ana C. Garrido-Castro, Lauren Buckley, Romualdo Barroso-Sousa, Brittany Bychkovsky, Sara Tolaney, Laura MacConaill, Neal Lindeman, Bruce Johnson, Matthew Meyerson, Eric Winer, Deborah A. Dillon, Andrew Cherniack, Nancy U. Lin. Tumor Genomic Landscape in Older Women with Metastatic Breast Cancer (MBC) [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P5-14-06.