Molecular characterisation of aromatase inhibitor-resistant advanced breast cancer: the phenotypic effect of ESR1 mutations.

BACKGROUND:Several thousand breast cancer patients develop resistance to aromatase inhibitors (AIs) each year in the UK. Rational treatment requires an improved molecular characterisation of resistant disease. MATERIALS AND METHODS:The mutational landscape of 198 regions in 16 key breast cancer genes and RNA expression of 209 genes covering key pathways was evaluated in paired biopsies before AI treatment and at progression on AI from 48 patients. Validity of findings was assessed in another five ESR1-mutated tumours progressing on AI. RESULTS:Eighty-nine mutations were identified in 41 matched pairs (PIK3CA in 27%; CDH1 in 20%). ESR1 (n = 5), ERBB2 (n = 1) and MAP2K4 (n = 1) had mutations in the secondary sample only. There was very high heterogeneity in gene expression between AI-resistant tumours with few patterns apparent. However, in the ESR1-mutated AI-resistant tumours, expression of four classical oestrogen-regulated genes (ERGs) was sevenfold higher than in ESR1 wild-type tumours, a finding confirmed in the second set of ESR1-mutated tumours. In ESR1 wild-type AI-resistant tumours ERG expression remained suppressed and was uncoupled from the recovery seen in proliferation. CONCLUSIONS:Major genotypic and phenotypic heterogeneity exists between AI-resistant disease. ESR1 mutations appear to drive oestrogen-regulated processes in resistant tumours

Biological network-driven gene selection identifies a stromal immune module as a key determinant of triple-negative breast carcinoma prognosis

Triple-negative breast cancer (TNBC) is a heterogeneous group of aggressive breast cancers for which no targeted treatment is available. Robust tools for TNBC classification are required, to improve the prediction of prognosis and to develop novel therapeutic interventions. We analyzed 3,247 primary human breast cancer samples from 21 publicly available datasets, using a five-step method: (1) selection of TNBC samples by bimodal filtering on ER-HER2 and PR, (2) normalization of the selected TNBC samples, (3) selection of the most variant genes, (4) identification of gene clusters and biological gene selection within gene clusters on the basis of String© database connections and gene-expression correlations, (5) summarization of each gene cluster in a metagene. We then assessed the ability of these metagenes to predict prognosis, on an external public dataset (METABRIC). Our analysis of gene expression (GE) in 557 TNBCs from 21 public datasets identified a six-metagene signature (167 genes) in which the metagenes were enriched in different gene ontologies. The gene clusters were named as follows: Immunity1, Immunity2, Proliferation/DNA damage, AR-like, Matrix/Invasion1 and Matrix2 clusters respectively. This signature was particularly robust for the identification of TNBC subtypes across many datasets (n = 1,125 samples), despite technology differences (Affymetrix© A, Plus2 and Illumina©). Weak Immunity two metagene expression was associated with a poor prognosis (disease-specific survival; HR = 2.68 [1.59–4.52], p = 0.0002). The six-metagene signature (167 genes) was validated over 1,125 TNBC samples. The Immunity two metagene had strong prognostic value. These findings open up interesting possibilities for the development of new therapeutic interventions

Solitary splenic metastasis from nasopharyngeal carcinoma: a case report and systematic review of the literature

Background: Solitary splenic metastases are a rare occurrence, and the nasopharyngeal carcinoma represents one of the most uncommon primary sources. The present study aimed to describe a rare case of a solitary single splenic metastasis from nasopharyngeal carcinoma and to assess the number of cases of isolated nasopharyngeal carcinoma metastases to the spleen reported in the literature. Main body: We describe the case of a 56-year-old man with a history of nasopharyngeal carcinoma and complete remission after chemo-radiotherapy. Three months after complete remission, positron emission tomography/ computed tomography scan revealed a hypermetabolic splenic lesion without increased metabolic activity in other areas. After laparoscopic splenectomy, the pathology report confirmed a single splenic metastasis from undifferentiated carcinoma of the nasopharyngeal type. The postoperative period was uneventful. We also performed a systematic review of the literature using MEDLINE and Google Scholar databases. All articles reporting cases of splenic metastases from nasopharyngeal carcinoma, with or without histologic confirmation, were evaluated. The literature search yielded 15 relevant articles, which were very heterogeneous in their aims and methods and described only 25 cases of splenic metastases from nasopharyngeal carcinoma. Conclusion: The present review shows that solitary splenic metastases from nasopharyngeal carcinoma are a rare event, but it should be considered in patients presenting with splenic lesions at imaging and a history of primary or recurrent nasopharyngeal carcinoma. No evidence supports a negative impact of splenectomy in patients with solitary splenic metastasis from nasopharyngeal carcinoma