Molecular changes in lobular breast cancers in response to endocrine therapy
Ontology highlight
ABSTRACT: Invasive lobular cancer (ILC) accounts for approximately 10-15% of breast carcinomas and although it responds poorly to neoadjuvant chemotherapy, it appears to respond well to endocrine therapy. Pre- and on-treatment (after 2 weeks and 3 months) biopsies and surgical samples were obtained from 14 post-menopausal women with ER+ histologically confirmed ILC who responded to 3 months of neoadjuvant letrozole and were compared with a cohort of 14 responding infiltrating ductal carcinomas (IDCs) matched on clinicopathological features by gene expression profiling. Dynamic clinical response was assessed using periodic 3D ultrasound measurements performed during treatment and defined as a reduction of >70% in tumour volume by 3 months. The changes in gene expression in response to letrozole were highly consistent between responding ILC and IDC tumours, genes involved in proliferation were down-regulated and those involved with immune function and ECM remodelling were up-regulated. However, molecular differences between the histological subtypes were maintained upon treatment. This is the first study of molecular changes in ILC in response to endocrine therapy to date. The genes which change on letrozole are highly consistent between ILC and IDC. Differences in gene expression between ILC and IDC at diagnosis and are maintained at each time point on treatment.
ORGANISM(S): Homo sapiens
PROVIDER: GSE55374 | GEO | 2014/08/11
SECONDARY ACCESSION(S): PRJNA239428
REPOSITORIES: GEO
ACCESS DATA