The Predictive Value of Serum HER2/neu for Response to Anthracycline-Based and Trastuzumab-Based Neoadjuvant Chemotherapy

A Multicolor Immunosensor for Sensitive Visual Detection of Breast Cancer Biomarker Based on Sensitive NADH-Ascorbic-Acid-Mediated Growth of Gold Nanobipyramids

Many studies have demonstrated that the extracellular domain of human epidermal growth factor receptor 2 (HER2 ECD) level in serum can act as a breast cancer biomarker and serve as a monitoring neoadjuvant therapy of breast cancer. In this study, we developed a sensitive ascorbic acid (AA)-mediated AuNBPs (gold nanobipyramids) growth method with NADH (reduced nicotinamide adenine dinucleotide I) assistance, and we further fabricated a high-resolution multicolor immunosensor for sensitive visual detection of HER2 ECD in serum by using AuNBPs as signal and antibody as recognition probe. The NADH-assisted AA-mediated method effectively suppressed color formation in the blank and greatly improved the sensitivity of mediating AuNBPs growth, allowing us to use a low concentration of AA to mediate AuNBPs growth to generate more colorful and clearer color changes. The proposed multicolor immunosensor has higher resolution and more color changes corresponding to HER2 ECD concentrations. It can be used to detect as low as 0.5 ng/mL of HER2 ECD by bare eye observation and 0.05 ng/mL of HER2 ECD by UV-visible spectrophotometry. Using the immunosensor, we have successfully detected HER2 ECD in human serum with a recovery of 94%-96% and an RSD (n = 5) < 5%. The results obtained with our immunosensor were consistent with those obtained with ELISA, verifying the immunosensor has good accuracy. The immunosensor exhibited a vivid multicolor change, has low visual detection limit, excellent specificity and reproducibility, and robust resistance to matrix. All the above features makes our immunosensor a promising assay for the early diagnosis of HER2-dependent breast cancers in clinical diagnosis.

The Significance of Serum HER2 Levels at Diagnosis on Intrinsic Subtype-Specific Outcome of Operable Breast Cancer Patients

Purpose

This study evaluated the association of serum HER2 (sHER2) levels at diagnosis with clinicopathologic parameters and disease free survival (DFS) in operable breast cancer patients according to intrinsic subtype.

Methods

The sHER2 levels were measured using a chemiluminescence immunoassay. The HER2 status in all tumor tissues was determined by immunohistochemistry, and confirmed in equivocal cases by fluorescence in situ.

Results

There were 436 consecutive stage I-III breast cancer patients with sHER2 result at diagnosis between Nov 2004 and Dec 2011. High sHER2 levels (≥ 15 ng/ml) were reported in 52 patients (11.9%) and HER2 overexpression in tumor tissue was observed in 111 patients (25.5%). High sHER2 levels were associated significantly with advanced stage (P < 0.001), mastectomy (P = 0.012), neoadjuvant chemotherapy (P < 0.001), anti-HER2 therapy (P < 0.001) and hormone therapy (P = 0.022). The patients with high sHER2 levels had a worse DFS (P < 0.001). In multivariate analysis, high sHER2 levels were associated significantly with worse DFS (HR = 2.25, 95% CI 1.27–3.99, P = 0.005). High sHER2 levels were associated with worse DFS in the HR+/HER2-, HR+/HER2+ and HR-/HER2+ subtypes (P = 0.043, 0.003 and 0.041, respectively).

Conclusions

These results show that the sHER2 level at diagnosis is a useful prognostic factor in patients with operable breast cancer, especially in the HR+/HER2-, HR+/HER2+ and HR-/HER2+ subtypes.

Serum thymidine kinase 1 levels predict cancer-free survival following neoadjuvant, surgical and adjuvant treatment of patients with locally advanced breast cancer

In this study, the use of serum thymidine kinase 1 protein (STK1p) concentration for the prognosis of the overall survival of patients with locally advanced breast cancer (n=51) following routine treatment (neoadjuvant treatment, surgery and chemotherapy) was investigated. The patients were followed up for 44 months and the STK1p values were determined by a high-sensitivity enhanced chemiluminescence (ECL) dot blot assay. The variables investigated in relation to metastasis and survival were STK1p, clinical stage, tumor size and age, by the Kaplan-Meier method, the log-rank test and Cox uni- and multivariate analyses. Patients with high STK1p values (≥2.0 pM) 3–6 months after surgery exhibited a positive correlation to clinical stage, tumor size, occurrence of metastasis and survival. The hazard risk for the development of metastatic disease and mortality among breast cancer patients was 11–12 times higher in patients with high compared to those with low STK1p values (<2.0 pM). Notably, patients with stage III/IV disease and low STK1p values exhibited statistically significantly improved survival compared to patients with high STK1p values. A multivariate Cox analysis demonstrated that the STK1p levels 6 months after surgery was the only independent prognostic factor for metastasis and survival. In conclusion, STK1p is a prognostic marker in patients with locally advanced breast cancer and it may help identify a subgroup of stage III/IV patients with improved cancer-free survival expectancy, enabling personalized treatment.