Springer Science and Business Media LLC

Mammaglobin-A (MGBA), a 10-kD protein, is over expressed in 80% of primary and metastatic human breast cancers. Breast cancer patients demonstrate high frequencies of CD8+ cytotoxic T lymphocytes (CTL) specific to MGBA. Defining CD8+ CTL responses to HLA class I-restricted MGBA-derived epitopes assumes significance in the context of our ongoing efforts to clinically translate vaccine strategies targeting MGBA for prevention and/or treatment of human breast cancers. In this study, we define the CD8+ CTL response to MGBA-derived candidate epitopes presented in the context of HLA-B7, which has a frequency of 17.7% in Caucasian and 15.5% in African American populations. We identified seven MGBA-derived candidate epitopes with high predicted binding scores for HLA-B7 using a computer algorithm. Membrane stabilization studies with TAP-deficient T2 cells transfected with HLA-B7 indicated that MGBA B7.3 (VSKTEYKEL), B7.6 (KLLMVLMLA), B7.7 (NPQVSKTEY), and B7.1 (YAGSGCPLL) have the highest HLA-B7 binding affinities. Further, two CD8+ CTL cell lines generated in vitro against T2.B7 cells individually loaded with MGBA-derived candidate epitopes showed significant cytotoxic activity against MGBA B7.1, B7.3, B7.6, and B7.7. In addition, the same CD8+ CTL lines lysed the HLA-B7+/MGBA+ human breast cancer cell line DU-4475 but had no significant cytotoxicity against HLA-B7− or MGBA− breast cancer cell lines. Cold-target inhibition studies strongly suggest that MGBA B7.3 is an immunodominant epitope. In summary, our results define HLA-B7-restriced, MGBA-derived, CD8+ CTL epitopes with all of the necessary features for developing novel vaccine strategies against HLA-B7 expressing breast cancer patients.

Establishing accurate estimates of physical activity at baseline is essential for interventions assessing the potential benefits of exercise in adults with cancer. This study compares self-reported physical activity with independent data from activity trackers in women with early breast cancer (BC) recruited into a “walking” intervention during chemotherapy. Baseline (pre-intervention) questions inquired about self-reported physical activity—number of walking days/week and minutes/day—in women who were initiating chemotherapy for Stage I–III BC. Activity trackers measured steps per day during the first full week of chemotherapy. Weighted Kappa statistic and Pearson correlation coefficients were used to evaluate agreement and association between self-reported and objectively tracked physical activity levels, respectively. Univariate analyses were conducted to identify variables that may influence congruence between the two measures. In a sample of 161 women, 77% were white, with mean age 56 years. Agreement between self-reported and objectively tracked physical activity was “fair” (kappa coefficient = 0.31), with most patients (59%) over-reporting their physical activity levels. There was weak correlation between the two measures (r = 0.24); however, correlation was strong in participants who were not married (r = 0.53) and/or living alone (r = 0.69). Objective methods for assessing physical activity (activity trackers, accelerometers) should be used as a complement to self-reported measures to establish credible activity levels for intervention studies seeking to increase physical activity and/or measure the impact of increased physical activity in women with breast cancer.

Although there is abundant information about the independent effects of estrogen receptor (ER) and progesterone receptor (PR) on outcomes of breast cancer, comparatively little is known about the impact of joint (ER+PR+, ER+PR−, ER−PR+ and ER−PR−) ERPR expression. The purpose of this study was to evaluate the prognostic relevance of joint ERPR expression to progression free survival (PFS). Data from 710 patients with a median follow-up of 119 months has been analyzed retrospectively. Our results indicate that the effect of the ER+PR+ phenotype on PFS was significantly time-dependent (p < 0.0001); favorable in the first 3 years of follow-up (HR = 0.67, p = 0.0175) compared to ER−PR− phenotype, but unfavorable during the later follow-up period (HR =  2.89, p = 0.0006). Similar patterns were also observed for ER+PR− and ER−PR+ phenotypes, but the effect did not reach statistical significance. In the tree-based analysis, we found that, among patients with more than 4 positive nodes and age greater than 40, those with ER−PR+ tumors had the worst PFS ( p = 0.025), and among patients with 1–3 positive nodes and stage of T1 and T2, those with ER+PR− had the worst outcome ( p = 0.006). Our results demonstrate that failure to recognize the time-varying effect of the steroid hormonal receptors can obscure their role in the prognosis of breast cancer. We also provide more evidence to support the concept that ER−PR+ is a real group representing a distinct clinical entity.

HER2 overexpression/amplification is linked with poor prognosis in early breast cancer. Co-expression of HER2 and HER3 is associated with endocrine and chemotherapy resistance, driven not simply by expression but by signalling via HER2:HER3 or HER2:HER2 dimers. Proximity ligation assays (PLAs) detect protein–protein complexes at a single-molecule level and allow study of signalling pathways in situ. A cohort of 100 tumours was analyzed by PLA, IHC and FISH. HER complexes were analyzed by PLA in a further 321 tumours from the BR9601 trial comparing cyclophosphamide, methotrexate and fluorouracil (CMF) with epirubicin followed by CMF (epi-CMF). The relationships between HER dimer expression and RFS and OS were investigated, and multivariate regression analysis identified factors influencing patient prognosis. PLA successfully and reproducibly detected HER2:HER2 and HER2:HER3 protein complexes in vivo. A significant association (P < 0.00001) was identified between HER2 homodimerization and HER2 gene amplification. Following a minimum p value approach high levels of HER2:HER2 dimers were significantly associated with reduced relapse-free (RFS; hazard ratio = 1.72, 95% confidence interval 1.15–2.56, P = 0.008) and overall survival (OS HR = 1.69 95% CI = 1.09–2.62, P = 0.019). Similarly, high levels of HER2:HER3 dimers were associated with reduced RFS (HR = 2.18, 95% CI = 1.46–3.26, P = 0.00016) and OS (HR = 2.21, 95% CI = 1.41–3.47, P = 0.001). This study demonstrates that in situ detection of HER2 and HER2:3 protein:protein complexes can be performed robustly and reproducibly in clinical specimens, provides novel prognostic information and opens a significant novel opportunity to probe the clinical impact of cellular signalling processes.

The prognostic significance of ultrasound real-time elastography (RTE) in patients with breast lesions is controversial. There are two different diagnostic methods: the elasticity score (ES) and the strain ratio (SR). A meta-analysis was performed using a random-effect model to assess the overall sensitivity and specificity of RTE in the differentiation of breast lesions. MEDLINE, EMBASE, PubMed, and the Cochrane Library before February 2011 were searched. A total of 22 studies, which included 4,713 breast nodules in 4,266 patients were analyzed. The overall mean sensitivity and specificity for the diagnosis of malignant breast lesions by RTE were 0.834 [95% confidence interval (CI) 0.814–0.853] and 0.842 (95% CI, 0.829–0.854) for ES, and 0.883 (95% CI, 0.844–0.916) and 0.814 (95% CI, 0.786–0.839) for SR, respectively. RTE has a high sensitivity and specificity in the evaluation of breast lesions and can potentially reduce unnecessary breast biopsies.