0000000000199528

AUTHOR

Angel Guerrero-zotano

Dynamic clonal remodelling in breast cancer metastases is associated with subtype conversion

Background: Changes in the clinical subtype (CS) and intrinsic subtype (IS) between breast cancer (BC) metastases and corresponding primary tumours have been reported. However, their relationship with tumour genomic changes remains poorly characterised. Here, we analysed the association between genomic remodelling and subtype conversion in paired primary and metastatic BC samples. Methods: A total of 57 paired primary and metastatic tumours from GEICAM/2009-03 (ConvertHER, NCT01377363) study participants with centrally assessed CS (n = 57) and IS (n = 46) were analysed. Targeted capture and next-generation sequencing of 202 genes on formalin-fixed paraffin-embedded samples was performed. Th…

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A polymorphism at the 3'-UTR region of the aromatase gene defines a subgroup of postmenopausal breast cancer patients with poor response to neoadjuvant letrozole

Abstract Background Aromatase (CYP19A1) regulates estrogen biosynthesis. Polymorphisms in CYP19A1 have been related to the pathogenesis of breast cancer (BC). Inhibition of aromatase with letrozole constitutes the best option for treating estrogen-dependent BC in postmenopausal women. We evaluate a series of polymorphisms of CYP19A1 and their effect on response to neoadjuvant letrozole in early BC. Methods We analyzed 95 consecutive postmenopausal women with stage II-III ER/PgR [+] BC treated with neoadjuvant letrozole. Response to treatment was measured by radiology at 4th month by World Health Organization (WHO) criteria. Three polymorphisms of CYP19A1, one in exon 7 (rs700519) and two in…

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Abstract PD1-05: Latest findings from the breast cancer cohort in SUMMIT - a phase 2 ‘basket’ trial of neratinib + trastuzumab + fulvestrant for HER2-mutant, hormone receptor-positive, metastatic breast cancer

Abstract Background: HER2 mutations are oncogenic in hormone receptor positive (HR+) metastatic breast cancer (MBC), and may confer resistance to prior endocrine therapy but retain sensitivity to neratinib. Neratinib is an oral, irreversible, pan-HER tyrosine kinase inhibitor with clinical activity either as a single agent or in combination with fulvestrant in HER2-mutated, HER2-non-amplified MBC. Genomic analyses suggest that acquired resistance to neratinib can occur via additional HER2 alterations, which may alter HER2-pathway signaling. We investigated whether dual HER2-targeted therapy could improve clinical benefit in a cohort of patients with HER2-mutant, HR+ MBC treated with neratin…

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MamaPred: A new and innovative approach to determine recurrence risk in HR+/HER2- early-stage breast cancer using HTG EdgeSeq technology.

558 Background: Genomic platforms, such as Mammaprint (Agendia) (MP) and OncoType (Genomic Health) (OT), have been validated to determine the risk of relapse in therapeutic decision-making in early-stage hormone receptor positive (HR+), epidermal growth factor receptor 2 (HER2) negative breast cancer (BC). Discordances in risk allocation between these platforms affect up to 30% of patients. This study aims to develop the MamaPred test to improve the diagnostic performance of recurrence risk in HR+/HER2- early-stage BC. Methods: A total of 606 HR+/HER2- early-stage BC previously tested with OT [n = 287; Low Risk (LR) = 165, Intermediate Risk (IR) = 103 and High Risk (HR) = 19] and MP (n = 3…

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Familial breast cancer in Spain: A retrospective study of family history and clinical/pathologic characteristics from the GEICAM “El Álamo III” project.

e12513 Background: Family history (FH) of breast cancer (BC), ovarian cancer (OC), and individual features (IF), like early age of onset, bilateral BC, coexistence of BC and OC, and triple negative BC (TNBC) younger than 50 years, are suspicion criteria of hereditary BC. Although it is assumed in the literature that 15-30% of BC cases can be familial BC (FBC), only 5-10% of BC are hereditary, explained by a germline mutation in BRCA1 or 2. Moreover, there is no international consensus to define FBC (e.g. number of relatives affected, age of onset), in contrast with, e.g. Lynch syndrome and Amsterdam/Bethesda criteria, in order to offer genetic counseling. In Spain, there are not population…

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MYC and MCL1 Cooperatively Promote Chemotherapy-Resistant Breast Cancer Stem Cells via Regulation of Mitochondrial Oxidative Phosphorylation

Summary Most patients with advanced triple-negative breast cancer (TNBC) develop drug resistance. MYC and MCL1 are frequently co-amplified in drug-resistant TNBC after neoadjuvant chemotherapy. Herein, we demonstrate that MYC and MCL1 cooperate in the maintenance of chemotherapy-resistant cancer stem cells (CSCs) in TNBC. MYC and MCL1 increased mitochondrial oxidative phosphorylation (mtOXPHOS) and the generation of reactive oxygen species (ROS), processes involved in maintenance of CSCs. A mutant of MCL1 that cannot localize in mitochondria reduced mtOXPHOS, ROS levels, and drug-resistant CSCs without affecting the anti-apoptotic function of MCL1. Increased levels of ROS, a by-product of a…

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Intrinsic Subtypes and Gene Expression Profiles in Primary and Metastatic Breast Cancer.

Biological changes that occur during metastatic progression of breast cancer are still incompletely characterized. In this study, we compared intrinsic molecular subtypes and gene expression in 123 paired primary and metastatic tissues from breast cancer patients. Intrinsic subtype was identified using a PAM50 classifier and χ2 tests determined the differences in variable distribution. The rate of subtype conversion was 0% in basal-like tumors, 23.1% in HER2-enriched (HER2-E) tumors, 30.0% in luminal B tumors, and 55.3% in luminal A tumors. In 40.2% of cases, luminal A tumors converted to luminal B tumors, whereas in 14.3% of cases luminal A and B tumors converted to HER2-E tumors. We ident…

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ER+ Breast Cancers Resistant to Prolonged Neoadjuvant Letrozole Exhibit an E2F4 Transcriptional Program Sensitive to CDK4/6 Inhibitors

AbstractPurpose: This study aimed to identify biomarkers of resistance to endocrine therapy in estrogen receptor–positive (ER+) breast cancers treated with prolonged neoadjuvant letrozole.Experimental Design: We performed targeted DNA and RNA sequencing in 68 ER+ breast cancers from patients treated with preoperative letrozole (median, 7 months).Results: Twenty-four tumors (35%) exhibited a PEPI score ≥4 and/or recurred after a median of 58 months and were considered endocrine resistant. Integration of the 47 most upregulated genes (log FC > 1, FDR < 0.03) in letrozole-resistant tumors with transcription-binding data showed significant overlap with 20 E2F4-regulated genes (P =…

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