STAT3 activation in HER2-positive breast cancers: Analysis of data from a large prospective trial.

The JAK/STAT3 signaling pathway may be aberrantly activated and have various and conflicting roles in breast cancer. The current study explored prognostic implications of activated STAT3 in human epidermal growth factor receptor 2 (HER2)-positive primary breast cancers in the context of a large prospective study (ALTTO). Activated STAT3 was determined by immunohistochemical analysis of STAT3 phosphorylation (Y705) performed on the primary tumors.

High-Sensitivity Troponin T and NT-proBNP Kinetics in Breast Cancer Chemotherapy.

Background/aims: Doxorubicin (DOX) and trastuzumab (TRA) are associated with cardiac dysfunction.

Method: High-sensitivity troponin T (hs-TnT) and brain natriuretic peptide attached to the amino acid N-terminal fragment in the prohormone (NT-proBNP) were measured before and on days +1, +2, +3, and +7 during cycles 1 and 2 of therapy with DOX or TRA in breast cancer patients.

Results: Five of eleven DOX-treated women, compared with 2/11 TRA-treated women, had undetectable baseline hs-TnT.

SLCO1B1 polymorphisms and plasma estrone conjugates in postmenopausal women with ER+ breast cancer: genome-wide association studies of the estrone pathway.

Background: Estrone (E1), the major circulating estrogen in postmenopausal women, promotes estrogen-receptor positive (ER+) breast tumor growth and proliferation. Two major reactions contribute to E1 plasma concentrations, aromatase (CYP19A1) catalyzed E1 synthesis from androstenedione and steroid sulfatase (STS) catalyzed hydrolysis of estrone conjugates (E1Cs). E1Cs have been associated with breast cancer risk and may contribute to tumor progression since STS is expressed in breast cancer where its activity exceeds that of aromatase.