10 research outputs found

    HER2-enriched subtype and novel molecular subgroups drive aromatase inhibitor resistance and an increased risk of relapse in early ER+/HER2+ breast cancer

    Get PDF
    BACKGROUND: Oestrogen receptor positive/ human epidermal growth factor receptor positive (ER+/HER2+) breast cancers (BCs) are less responsive to endocrine therapy than ER+/HER2- tumours. Mechanisms underpinning the differential behaviour of ER+HER2+ tumours are poorly characterised. Our aim was to identify biomarkers of response to 2 weeksā€™ presurgical AI treatment in ER+/HER2+ BCs. METHODS: All available ER+/HER2+ BC baseline tumours (n=342) in the POETIC trial were gene expression profiled using BC360ā„¢ (NanoString) covering intrinsic subtypes and 46 key biological signatures. Early response to AI was assessed by changes in Ki67 expression and residual Ki67 at 2 weeks (Ki672wk). Time-To-Recurrence (TTR) was estimated using Kaplan-Meier methods and Cox models adjusted for standard clinicopathological variables. New molecular subgroups (MS) were identified using consensus clustering. FINDINGS: HER2-enriched (HER2-E) subtype BCs (44.7% of the total) showed poorer Ki67 response and higher Ki672wk (p<0.0001) than non-HER2-E BCs. High expression of ERBB2 expression, homologous recombination deficiency (HRD) and TP53 mutational score were associated with poor response and immune-related signatures with High Ki672wk. Five new MS that were associated with differential response to AI were identified. HER2-E had significantly poorer TTR compared to Luminal BCs (HR 2.55, 95% CI 1.14ā€“5.69; p=0.0222). The new MS were independent predictors of TTR, adding significant value beyond intrinsic subtypes. INTERPRETATION: Our results show HER2-E as a standardised biomarker associated with poor response to AI and worse outcome in ER+/HER2+. HRD, TP53 mutational score and immune-tumour tolerance are predictive biomarkers for poor response to AI. Lastly, novel MS identify additional non-HER2-E tumours not responding to AI with an increased risk of relapse

    Uptake, distribution and depuration of paralytic shellfish toxins from Alexandrium minutum in Australian greenlip abalone, Haliotis laevigata

    No full text
    Farmed greenlip abalone Haliotis laevigata were fed commercial seaweed-based food pellets or feed pellets supplemented with 8 Ɨ 10āµ Alexandrium minutum dinoflagellate cells gā»Ā¹ (containing 12 Ā± 3.0 Ī¼g STX-equivalent 100 gā»Ā¹, which was mainly GTX-1,4) every second day for 50 days. Exposure of abalone to PST supplemented feed for 50 days did not affect behaviour or survival but saw accumulation of up to 1.6 Ī¼g STX-equivalent 100 gā»Ā¹ in the abalone foot tissue (muscle, mouth without oesophagus and epipodial fringe), which is āˆ¼50 times lower than the maximum permissible limit (80 Ī¼g 100 gā»Ā¹ tissue) for PSTs in molluscan shellfish. The PST levels in the foot were reduced to 0.48 Ī¼g STX-equivalent 100 gā»Ā¹ after scrubbing and removal of the pigment surrounding the epithelium of the epipodial fringe (confirmed by both HPLC and LC-MS/MS). Thus, scrubbing the epipodial fringe, a common procedure during commercial abalone canning, reduced PST levels by āˆ¼70%. Only trace levels of PSTs were detected in the viscera (stomach, gut, heart, gonad, gills and mantle) of the abalone. A toxin reduction of approximately 73% was observed in STX-contaminated abalone held in clean water and fed uncontaminated food over 50 days. The low level of PST uptake when abalone were exposed to high numbers of A. minutum cells over a prolonged period may indicate a low risk of PSP poisoning to humans from the consumption of H. laevigata that has been exposed to a bloom of potentially toxic A. minutum in Australia. Further research is required to establish if non-dietary accumulation can result in significant levels of PSTs in abalone.Natalie Dowsett, Gustaaf Hallegraeff, Paul van Ruth, Roel van Ginkel, Paul McNabb, Brenda Hay, Wayne O'Connor, Andreas Kiermeier, Marty Deveney, Catherine McLeo

    Sex hormones and risk of breast cancer in premenopausal women: a collaborative reanalysis of individual participant data from seven prospective studies.

    No full text
    BACKGROUND: Associations between circulating concentrations of oestrogens, progesterone, and androgens with breast cancer and related risk factors in premenopausal women are not well understood. We aimed to characterise these associations with a pooled analysis of data from seven studies. METHODS: Individual participant data for prediagnostic sex hormone and sex hormone-binding globulin (SHBG) concentrations were contributed from seven prospective studies. We restricted analyses to women who were premenopausal and younger than 50 years at blood collection, and to women with breast cancer diagnosed before age 50 years. We estimated odds ratios (ORs) with 95% CIs for breast cancer associated with hormone concentrations by conditional logistic regression in cases and controls matched for age, date of blood collection, and day of cycle, with stratification by study and further adjustment for cycle phase. We examined associations of hormones with risk factors for breast cancer in control women by comparing geometric mean hormone concentrations in categories of these risk factors, adjusted for study, age, phase of menstrual cycle, and body-mass index (BMI). All statistical tests were two-sided. FINDINGS: We included data for up to 767 women with breast cancer and 1699 controls in the risk analyses. Breast cancer risk was associated with a doubling in concentrations of oestradiol (OR 1Ā·19, 95% CI 1Ā·06-1Ā·35), calculated free oestradiol (1Ā·17, 1Ā·03-1Ā·33), oestrone (1Ā·27, 1Ā·05-1Ā·54), androstenedione (1Ā·30, 1Ā·10-1Ā·55), dehydroepiandrosterone sulphate (1Ā·17, 1Ā·04-1Ā·32), testosterone (1Ā·18, 1Ā·03-1Ā·35), and calculated free testosterone (1Ā·08, 0Ā·97-1Ā·21). Breast cancer risk was not associated with luteal phase progesterone (doubling in concentration OR 1Ā·00, 95% CI 0Ā·92-1Ā·09), and adjustment for other factors had little effect on any of these ORs. Cross-sectional analyses in control women showed several associations of sex hormones with breast cancer risk factors. INTERPRETATION: Circulating oestrogens and androgens are positively associated with the risk for breast cancer in premenopausal women
    corecore