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Purpose: The RAS family comprises three proto-oncogenes (H-RAS, K-RAS, and N-RAS) and is among the most widely studied of oncogenes. The present study aimed at investigating the clinical relevance of mRNA levels of the three isoforms in a large group of breast cancer patients with a long-term follow-up., Methods: 198 previously untreated patients were enrolled in the study. mRNA levels of K-RAS, H-RAS, and N-RAS were measured using microarray (Affymetrix HG-U133A)., Results: Elevated H-RAS levels were found significantly more frequently in patients with larger (p = 0.021) and ER-positive tumors (p = 0.048), while elevated K-RAS levels were associated with nodal positivity (p = 0.001) and HER2-positivity (p = 0.010). Patients with high N-RAS mRNA levels were more likely to be diagnosed with triple-negativity (p < 0.001) and higher grading (p = 0.001). Patients with high K-RAS levels were more likely to show an elevated H-RAS (p = 0.003). After a median follow-up of 183 months, patients with high N-RAS expression had significantly reduced overall survival (OS) compared with patients with low N-RAS (mean: 146.9 vs. 211.0 months; median 169.3 vs. not reached; p = 0.009). In patients with non-metastatic disease at the time of tissue sampling, mean disease-free survival (DFS) was 150.1 months for patients with high N-RAS versus 227.7 months with low N-RAS; median DFS was not reached (p = 0.004). The expression of H-RAS and K-RAS was not associated with DFS/OS. In the multivariable analysis, distant metastasis, HER2 positivity, and elevated N-RAS mRNA levels independently predicted reduced OS, while nodal status, HER2 status, and N-RAS predicted reduced DFS., Conclusions: Elevated N-RAS mRNA levels predict impaired clinical outcome; hypothetically, further exploration of the RAS signaling pathway might enable identifying potential targeted treatment strategies. The association between high N-RAS levels and the most aggressive among breast cancer subtypes, the triple-negative phenotype, for which targeted approaches are still lacking, underlines the need to further investigate the RAS family.

Purpose: VEGF is one of the most important angiogenesis-stimulating cytokines and has been previously shown to be overexpressed in several solid cancers. The aim of the present study was to assess the clinical relevance of serum VEGF (sVEGF) in a large cohort of metastatic breast cancer patients and to explore the relationship between sVEGF and other blood-based biomarkers., Methods: Two hundred fifty-three patients with metastatic breast cancer were enrolled in this prospective, multicentre study. Blood samples were collected before start of first-line or later-line treatment. sVEGF was quantified by a commercially available ELISA. Circulating tumor cells (CTCs) were detected using CellSearch and other biomarkers (EGFR, HER2, RAS p21, TIMP1, CAIX) by ELISA., Results: Levels of sVEGF were determined in all patients, with a median concentration of 231 pg/ml. After a median follow-up of 19 months, median overall survival (OS) was 10.2 months in patients with sVEGF levels above the upper quartile (i.e. 367 pg/ml), while median OS has not been reached in patients with sVEGF < 367 pg/ml (p < 0.001). Median progression-free survival (PFS) was 4.8 months for patients with sVEGF ≥ 367 pg/ml versus 9.1 months with sVEGF levels < 367 pg/ml (p < 0.001). Patients with sVEGF levels ≥ 367 pg/ml and ≥ 5 CTCs had the shortest OS, while those with sVEGF < 367 pg/ml and non-elevated CTCs had the longest OS. CTCs, grading, line of therapy and RAS p21 were independent predictors of OS. sVEGF, line of therapy and CTCs were independent predictors of PFS in the multivariate analysis., Conclusions: Metastatic breast cancer patients with elevated levels of sVEGF have significantly worse clinical outcome. This finding supports the biological role of VEGF in breast cancer., Trial Registration: Current Controlled Trials ISRCTN59722891 (DETECT).

Background: Although some studies suggest that breast-conserving therapy (BCT) shows better psychosocial outcomes than mastectomy in patients with primary breast cancer, little is known about the outcomes of these surgical options in recurrent breast cancer. We investigated differences in overall survival and re-recurrence rates as well as psychosocial outcomes among patients who underwent BCT or mastectomy after the diagnosis of recurrent breast cancer in a single-center setting., Methods: 124 of 186 eligible patients who underwent surgical treatment for breast cancer recurrence completed the questionnaires on quality of life (EORTC QLQ-C30 and -BR23), fear of progression (PA-F-KF), anxiety and depression (HADS), and body image (BIS)., Results: Women after breast-conserving surgery (n = 46) showed significantly better outcomes than women after mastectomy (n = 61) with respect to body image (P < 0.001 in BIS and p < 0.001 in BR23), social functioning (p = 0.016), emotional functioning (p = 0.028), and role functioning (p = 0.043). There were no significant group differences regarding anxiety, depression, and fear of progression as well as re-recurrence and survival rates. Predictors of good quality of life were partnership (OR 2.46), higher monthly family income (OR 3.54), and higher professional qualification (OR 4.3) in our group of patients., Discussion: Our results indicate that patients treated with breast-conserving therapy after recurrent breast cancer perceive lower impairments in body image and several aspects of quality of life than patients treated with mastectomy.

Background: The incidence of brain metastases in breast cancer patients has increased in the last years. However, the knowledge about tumor cell invasion in the brain is still very limited. Based on our recent study on cDNA microarray data of breast cancer patients, we hypothesized that two enzymes involved in the hyaluronan metabolism, namely, hyaluronan synthase 2 (HAS2) and hyaluronidase 1 (HYAL1) are associated with brain metastases formation., Methods: Protein expression levels of hyaluronan, HAS2, and HYAL1 were analyzed in primary breast cancer, and metastatic tissue samples from different localizations (brain, bone, skin, liver, and lung) were included in four different cohorts by immunohistochemistry. Correlations of expression levels with clinical and pathological parameters were performed within the individual cohorts., Results: Higher HYAL1 expression was detected among primary tumors from patients with subsequent brain metastases compared with those without brain metastases (p = 0.011). Interestingly, brain metastatic tissue showed a significantly reduced HYAL1 expression compared with the corresponding primary tumor (p = 0.003). HYAL1 expression in brain metastases was also significantly lower than in skin, liver, and lung metastases. Further, hyaluronan staining in brain metastases was mainly located on the surface of the tumor cells, whereas in all other metastatic sites hyaluronan was only detected in the extracellular matrix. We could not show an association of HAS2 with the formation of brain metastases., Conclusions: In conclusion, our results suggest that the enzyme HYAL1 plays a role in tumor dissemination and brain-specific colonization, rather than in subsequent metastatic out-growth.

To study the influence of glycosylation on breast cancer progression by analyses on glycan, mRNA, and protein level. For detection of glycan structures, we performed lectin histochemistry with five lectins of different specificity (UEA-1, HPA, GNA, PNA, and PHA-L) on a tissue microarray with >400 breast cancer samples. For comparison, mRNA expression of glycosylation enzymes involved in the synthesis of HPA and PNA binding glycostructures (GALNT family members and C1GALT1) was analyzed in microarray data of 194 carcinomas. Additionally, C1GALT1 protein expression was analyzed by Western blot analysis in 106 tumors. Correlations with clinical and histological parameters including recurrence-free (RFS) and overall survival (OAS) were calculated. Positive binding of four lectins (HPA, GNA, PNA, and PHA-L) correlated significantly with parameters involved in tumor metastasis, namely lymphangiosis, vascular invasion, lymph node involvement, and presence of disseminated tumor cells in bone marrow. HPA and PNA binding also showed a negative prognostic impact in our cohort. Correspondingly, high expression of C1GALT1, GALNT1, GALNT8, or GALNT14 mRNA and C1GALT1 protein correlated significantly with shorter OAS. Notably, combined overexpression of C1GALT1/GALNT1 or C1GALT1/GALNT8 mRNA was associated with a significantly reduced OAS (HR 3.15 and 2.73) and RFS (HR 2.01 and 1.94), pointing to an additive influence of these enzymes. This prognostic impact retained significance in multivariate analysis including classical prognostic markers. Our data indicate that glycan structures containing βGal-βGalNAc residues and the enzymes involved in their synthesis play a role in breast cancer progression, at least partly by their promoting influence on haematogenic and lymphatic spread.

Glycosylation of cellular proteins has important impact on their stability and functional properties, and glycan structures strongly influence cell adhesion. Many enzymes are involved in glycoconjugate synthesis and degradation, but there is only limited information about their role in breast cancer progression. Therefore, we retrieved RNA expression data of 202 glycosylation genes generated by microarray analysis (Affymetrix HG-U133A) in a cohort of 194 mammary carcinomas with long-term follow-up information. After univariate and multivariate Cox regression analysis, genes with independent prognostic value were identified. These were further analysed by Kaplan-Meier analysis and log-rank tests, and their prognostic value was validated in a second cohort of 200 tumour samples from patients without systemic therapy. In our first cohort, we identified 24 genes with independent prognostic value, coding for sixteen anabolic and eight catabolic enzymes. Functionally, these genes are involved in all important glycosylation pathways, namely O-glycosylation, N-glycosylation, O-fucosylation, synthesis of glycosaminoglycans and glycolipids. Eighteen genes also showed prognostic significance in chemotherapy-treated patients. In the second cohort, six of the 24 relevant genes were of prognostic significance (FUT1, FUCA1, POFUT1, MAN1A1, RPN1 and DPM1), whereas a trend was observed for three additional probesets (GCNT4, ST3GAL6 and UGCG). In a stratified analysis of molecular subtypes combining both cohorts, great differences appeared suggesting a predominant role of N-glycosylation in luminal cancers and O-glycosylation in triple-negative ones. Correlations of gene expression with metastases of various localizations point to a role of glycan structures in organ-specific metastatic spread. Our results indicate that various glycosylation reactions influence progression and metastasis of breast cancer and might thus represent potential therapeutic targets.

High proliferation rates are characteristic of cancer, and proliferation markers make up the majority of genes included in RNA-based prognostic gene signatures applied for breast cancer patients. Based on prior data on differences in molecular subgroups of breast cancer, we hypothesized that the significance of single proliferation markers might differ in luminal, Her2-positive and triple-negative subtypes. Therefore, we compared mRNA expression data of Ki67, TOP2A, and RacGAP1 using a pool of 562 Affymetrix U133A microarrays from breast cancer samples. "Luminal," "triple-negative," and "Her2-positive" subcohorts were defined by ESR1 and ERBB2 mRNA expression using pre-defined cut-offs. The analysis of the three potential proliferation markers revealed subtype-specific differences: in luminal carcinomas, expression of all three markers was a significant indictor of early recurrence in univariate and multivariate analysis, but RacGAP1 was superior to Ki67 and TOP2A in significance. In triple-negative tumors, only Ki67 was a significant and independent marker, whereas none of the markers showed a significant prognostic impact in Her2-positive cases. Within the group of luminal carcinomas, the proliferation markers had different impact depending on the treatment of patients: in untreated patients, Ki67, TOP2A, and RacGAP1 were significant and independent prognostic markers. In chemotherapy-treated patients, overexpression of all three markers was predictive for early recurrence, but only RacGAP1 retained significance in multivariate analysis. In contrast, RacGAP1 was the only predictive proliferation marker in the endocrine treatment group. These data point to subtype-specific differences in the relevance of proliferation-associated genes, and RacGAP1 might be a strong prognostic and predictive marker in the luminal subgroup.

In the context of neoadjuvant therapy (NT) for breast cancer patients, different targeted therapy approaches are currently evaluated in clinical trials. Serum markers could help to monitor and optimize such treatment strategies. We investigated human epidermal growth factor receptor 2 serum (sHER2) levels in 175 breast cancer patients participating in the GeparQuattro trial. This study incorporated NT approaches and additional trastuzumab treatment for all patients with HER2-positive tumors. Human epidermal growth factor receptor 2 serum levels were measured by enzyme-linked immunosorbent assay (ELISA) before initiation of NT and after NT (pre-surgery) in a HER2-positive (n = 90) and a HER2-negative patient cohort (n = 85). Median pre-chemotherapy sHER2 levels were higher in patients with positive HER2 status of the primary tumor than in patients with negative HER2 status (14.9 ng/ml vs. 7.7 ng/ml, P < 0.001). A pre-chemotherapy sHER2 cut-off level of 10 ng/ml had the best sensitivity and specificity in discriminating between HER2-positive and HER2-negative primary tumors. In HER2-positive patients, we found a significant positive association between pathological complete remission (pCR) and elevated sHER2 levels (above 15 ng/ml, P = 0.045) and a decrease of sHER2 levels during NT (P = 0.02), which was also significant in multivariate analysis (OR = 3.29, 95% CI 1.001-10.89, P = 0.049). In HER2-negative patients, we observed no association between sHER2 levels and pCR (P > 0.05). Monitoring sHER2 levels in the presence of anti-HER2 treatment might be an adjunct to the clinical evaluation during NT.

Background: The extracellular domain of the HER-2/neu -receptor (ECD) is shed from the receptor protein and can be detected in serum. However, the clinical implication of HER-2/neu ECD measurement must be further evaluated., Methods: In patients with metastatic breast cancer participating in a trial on first-line chemotherapy, the association of serum HER-2/neu ECD with progression-free interval, survival, and response was studied. Blood samples of patients receiving epirubicin and either cyclophosphamide (EC) or paclitaxel (ET) were collected before (n = 103) and in addition, after three courses of therapy (n = 46)., Results: HER-2/neu ECD levels correlate with HER-2/neu overexpression of corresponding primary tumors determined by immunohistochemistry (antibody CB11, p = 0.018) with an optimized cut-off at 15 ng/mL. Elevated serum levels of HER-2/neu ECD before chemotherapy were correlated with shorter overall survival (p = 0.0097), but not with reduced progression-free survival and response to chemotherapy. In subgroup analyses, patients with elevated pretherapeutic HER-2/neu ECD levels treated with EC showed shorter overall survival (p = 0.0092); no difference was seen in the ET group. With regard to progression-free survival, patients with elevated HER-2/neu ECD levels tended to benefit from ET (p = 0.0341), in patients with low levels no difference was observed between EC and ET. A decrease of HER-2/neu ECD levels after three courses of therapy was associated with response to therapy (p = 0.006)., Conclusion: In our group of metastatic breast cancer patients, elevated HER-2/neu ECD levels are associated with decreased overall survival. With regard to progression-free survival, particularly patients with high HER-2/neu ECD levels seem to benefit from taxane-containing chemotherapy.