Alternatively spliced tissue factor synergizes with the estrogen receptor pathway in promoting breast cancer progression.

BACKGROUND: Procoagulant full-length tissue factor (flTF) and its minimally coagulant alternatively spliced isoform (asTF), promote breast cancer (BrCa) progression via different mechanisms. We previously showed that flTF and asTF are expressed by BrCa cells, resulting in autoregulation in a cancer milieu. BrCa cells often express hormone receptors such as the estrogen receptor (ER), leading to the formation of hormone-regulated cell populations. OBJECTIVE: To investigate whether TF isoform-specific and ER-dependent pathways interact in BrCa. METHODS: Tissue factor isoform-regulated gene sets were assessed using ingenuity pathway analysis. Tissues from a cohort of BrCa patients were divided into ER-positive and ER-negative groups. Associations between TF isoform levels and tumor characteristics were analyzed in these groups. BrCa cells expressing TF isoforms were assessed for proliferation, migration and in vivo growth in the presence or absence of estradiol. RESULTS: Ingenuity pathway analysis pointed to similarities between ER- and TF-induced gene expression profiles. In BrCa tissue specimens, asTF expression was associated with grade and stage in ER-positive but not in ER-negative tumors. flTF was only associated with grade in ER-positive tumors. In MCF-7 cells, asTF accelerated proliferation in the presence of estradiol in a ß1 integrin-dependent manner. No synergy between asTF and the ER pathway was observed in a migration assay. Estradiol accelerated the growth of asTF-expressing tumors but not control tumors in vivo in an orthotopic setting. CONCLUSION: Tissue factor isoform and estrogen signaling share downstream targets in BrCa; the concomitant presence of asTF and estrogen signaling is required to promote BrCa cell proliferation.

Immunological subtypes in breast cancer are prognostic for invasive ductal but not for invasive lobular breast carcinoma.

BACKGROUND: Classical patient and tumour characteristics are the benchmark of personalised breast cancer (BC) management. Recent evidence has demonstrated that immune and molecular profiling of BC may also play an important role. Despite evidence of differences between invasive ductal (IDC) and lobular (ILC) BC, they are infrequently accounted for when making treatment decisions for individual patients. The purpose of this study was to investigate the relevance of the tumour immune response in the major histological subtypes of BC. We also assessed the relationship between immune responses and molecular subtypes and their prognostic potential. METHODS: Immunostains were done for HLA-I, HLA-E, HLA-G, Tregs, NK cells and CTLs for the composition of the immune profiles and Ki67, EGFR, CK5/6, ER, PR and HER2 for molecular profiles in 714 breast cancer patients who underwent primary surgery. RESULTS: No significant association was found between IDC (90.6%) and ILC (9.4%) and tumour immune subtypes (P=0.4) and molecular subtypes (P=0.4). However, for the relapse-free period (RFP) tumour immune subtyping was prognostic (P=0.002) in IDC, but not ILC. Contrary to ILC, IDC patients frequently expressed higher cleaved caspase-3 and Ki67, which was prognostic. Intermediate immune-susceptible IDC expressing high cleaved caspase-3 or Ki67 showed worse RFP than those with low expression (caspase-3: P=0.004; Ki67: P=0.002); this was not seen for ILC or in high or low immune-susceptible tumour types for either IDC or ILC. CONCLUSIONS: Tumour immune characteristics and host immune responses are prognostic in IDC, but not ILC. In addition, tumour immune profiles are only prognostic in Luminal A tumours.

Expression of cell adhesion molecules and prognosis in breast cancer.

BACKGROUND: Cell adhesion molecules (CAMs) play an important role in the process of metastasis. The prognostic value of tumour expression of N-cadherin, E-cadherin, carcinoembryonic antigen (CEA) and epithelial CAM (Ep-CAM) was evaluated in patients with breast cancer. METHODS: A tissue microarray of the patient cohort was stained immunohistochemically for all markers and analysed by microscopy. Expression was classified into two categories, with the median score as cut-off level. For CEA, the above-median category was further subdivided in two subgroups based on staining intensity (low or high intensity). RESULTS: The cohort consisted of 574 patients with breast cancer with a median follow-up of 19 years. Below-median expression of E-cadherin (P = 0·015), and above-median expression of N-cadherin (P = 0·004), Ep-CAM (P = 0·046) and CEA (P = 0·001) all resulted in a shorter relapse-free period. Multivariable analysis revealed E-cadherin and CEA to be independent prognostic variables. Combined analysis of CEA and E-cadherin expression showed a 3·6 times higher risk of relapse for patients with high-intensity expression of CEA, regardless of E-cadherin expression, compared with patients with below-median CEA and above-median E-cadherin tumour expression (hazard ratio 3·60, 95 per cent confidence interval 2·12 to 6·11; P < 0·001). An interaction was found between expression of these two CAMs (P < 0·001), suggesting a biological association. CONCLUSION: Combining E-cadherin and CEA tumour expression provides a prognostic parameter with high discriminative power that is a candidate tool for prediction of prognosis in breast cancer.

The prognostic role of TGF-ß signaling pathway in breast cancer patients.

BACKGROUND: The transforming growth factor-ß (TGF-ß) pathway has dual effects on tumor growth. Seemingly, discordant results have been published on the relation between TGF-ß signaling markers and prognosis in breast cancer. Improved prognostic information for breast cancer patients might be obtained by assessing interactions among TGF-ß signaling biomarkers. PATIENTS AND METHODS: The expression of nuclear Smad4, nuclear phosphorylated-Smad2 (p-Smad2), and the membranous expression of TGF-ß receptors I and II (TßRI and TßRII) was determined on a tissue microarray of 574 breast carcinomas. Tumors were stratified according to the Smad4 expression in combination with p-Smad2 expression or Smad4 in combination with the expression of both TGF-ß receptors. RESULTS: Tumors with high expression of TßRII, TßRI and TßRII, and p-Smad2 (P = 0.018, 0.005, and 0.022, respectively), and low expression of Smad4 (P = 0.005) had an unfavorable prognosis concerning progression-free survival. Low Smad4 expression combined with high p-Smad2 expression or low expression of Smad4 combined with high expression of both TGF-ß receptors displayed an increased hazard ratio of 3.04 [95% confidence interval (CI) 1.390-6.658] and 2.20 (95% CI 1.464-3.307), respectively, for disease relapse. CONCLUSIONS: Combining TGF-ß biomarkers provides prognostic information for patients with stage I-III breast cancer. This can identify patients at increased risk for disease recurrence that might therefore be candidates for additional treatment.