Hans Peter Sinn

Identification of a population of blood circulating tumor cells from breast cancer patients that initiates metastasis in a xenograft assay.

It has been hypothesized that carcinoma metastasis is initiated by a subpopulation of circulating tumor cells (CTCs) found in the blood of patients. However, although the presence of CTCs is an indicator of poor prognosis in several carcinoma entities, the existence and phenotype of metastasis-initiating cells (MICs) among CTCs has not been experimentally demonstrated. Here we developed a xenograft assay and used it to show that primary human luminal breast cancer CTCs contain MICs that give rise to bone, lung and liver metastases in mice. These MIC-containing CTC populations expressed EPCAM, CD44, CD47 and MET. In a small cohort of patients with metastases, the number of EPCAM+CD44+CD47+MET+ CTCs, but not of bulk EPCAM+ CTCs, correlated with lower overall survival and increased number of metastasic sites. These data describe functional circulating MICs and associated markers, which may aid the design of better tools to diagnose and treat metastatic breast cancer.

International Expert Panel on the Use of Primary (Preoperative) Systemic Treatment of Operable Breast Cancer: Review and Recommendations

Primary systemic therapy (PST) represents the standard of care in patients with locally advanced breast cancer. In addition, there is increasing information on PST in operable breast disease that supports the use of PST in routine practice. However, current regimens and techniques vary. To address this concern, a group of representatives from breast cancer clinical research groups in France, Germany, Italy, the United Kingdom, and the United States reviewed all available data on prospective randomized trials in this setting. Recommendations are made regarding terminology, indications, regimen, diagnosis before treatment, monitoring of efficacy, tumor localization, surgery, pathologic evaluation, and postoperative treatment.

Gene Expression Signature Predicting Pathologic Complete Response With Gemcitabine, Epirubicin, and Docetaxel in Primary Breast Cancer

PURPOSE Primary systemic therapy (PST) with gemcitabine (G), epirubicin (E), and docetaxel (Doc) has resulted in a pathologic complete response (pCR) in 26% of primary breast cancer patients. This study was aimed at the identification of a gene expression signature in diagnostic core biopsy tissue samples that predicts pCR. PATIENTS AND METHODS Core biopsy samples from patients with operable primary breast cancer, T2-4N0-2M0, enrolled onto two phase I and II trials evaluating GEDoc (n = 48) and GE sequentially followed by Doc (GEsDoc; n = 52) as PST were snap frozen and subjected to RNA expression profiling. A signature predicting pCR was discovered in the training set (GEsDoc) applying a support vector machine algorithm, and performance of this classifier was validated on the independent test set (GEDoc) by receiver operator characteristics analysis. RESULTS We identified a signature consisting of 512 genes, which was enriched in genes involved in transforming growth factor beta and RAS-mediated signaling pathways, that predicts pCR with a sensitivity of 78%, a specificity of 90%, and an overall accuracy of 88% (95% CI, 75% to 95%). Apart from our signature, only HER2 overexpression was an independent predictor of pCR in multivariate analysis. CONCLUSION In conclusion, our gene expression signature allows prediction of pCR to PST containing G, E, and Doc with unprecedented high overall accuracy and robustness.

The histone acetyltransferase hMOF is frequently downregulated in primary breast carcinoma and medulloblastoma and constitutes a biomarker for clinical outcome in medulloblastoma

Loss of H4 lysine 16 (H4K16) acetylation was shown to be a common feature in human cancer. However, it remained unclear which enzyme is responsible for the loss of this modification. Having recently identified the histone acetyltransferase human MOF (hMOF) to be required for bulk H4K16 acetylation, here we examined the involvement of hMOF expression and H4K16 acetylation in breast cancer and medulloblastoma. Analysis of a recent mRNA expression profiling study in breast cancer (n = 100 cases) and an array‐CGH screen in medulloblastomas (n = 102 cases), revealed downregulation in 40% and genomic loss in 11% of cases, respectively. We investigated hMOF protein expression as well as H4K16 acetylation in large series of primary breast carcinomas (n = 298) and primary medulloblastomas (n = 180) by immunohistochemistry. In contrast to nontransformed control tissues, significant fractions of both primary breast carcinomas and medulloblastomas showed markedly reduced hMOF mRNA and protein expression. In addition, hMOF protein expression tightly correlated with acetylation of H4K16 in all tested samples. For medulloblastoma, downregulation of hMOF protein expression was associated with lower survival rates identifying hMOF as an independent prognostic marker for clinical outcome in univariate as well as multivariate analyses.

Common Breast Cancer Susceptibility Loci Are Associated with Triple-Negative Breast Cancer

Triple-negative breast cancers are an aggressive subtype of breast cancer with poor survival, but there remains little known about the etiologic factors that promote its initiation and development. Commonly inherited breast cancer risk factors identified through genome-wide association studies display heterogeneity of effect among breast cancer subtypes as defined by the status of estrogen and progesterone receptors. In the Triple Negative Breast Cancer Consortium (TNBCC), 22 common breast cancer susceptibility variants were investigated in 2,980 Caucasian women with triple-negative breast cancer and 4,978 healthy controls. We identified six single-nucleotide polymorphisms, including rs2046210 (ESR1), rs12662670 (ESR1), rs3803662 (TOX3), rs999737 (RAD51L1), rs8170 (19p13.1), and rs8100241 (19p13.1), significantly associated with the risk of triple-negative breast cancer. Together, our results provide convincing evidence of genetic susceptibility for triple-negative breast cancer.

Synthetic antitumor vaccines containing MUC1 glycopeptides with two immunodominant domains-induction of a strong immune response against breast tumor tissues.

A shot in the arm for cancer treatment: two MUC1 tetanus toxoid vaccines were synthesized and induced a strong immune response in mice. The antibodies elicited by the vaccines show a high selectivity for the tumor cells in mammary carcinoma tissues and also distinguish between tumor tissues at different stages.

Genome-wide methylation screen in low-grade breast cancer identifies novel epigenetically altered genes as potential biomarkers for tumor diagnosis

Aberrant DNA methylation constitutes a well‐established epigenetic marker for breast cancer. Changes in methylation early in cancer development may be clinically relevant for cancer detection and prognosis‐based therapeutic decisions. In the present study, a combination of methyl‐CpG immunoprecipitation (MCIp) and human CpG island (CGI) arrays was applied to compare genome‐wide DNA methylation profiles in 10 low‐grade in situ and invasive breast cancers against 10 normal breast samples. In total, 214 CGIs were found to be hypermethylated in ≥6 of 10 tumors. Functional term enrichment analyses revealed an overrepresentation of homeobox genes and genes involved in transcription and regulation of transcription. Significant hypermethylation of 11 selected genes in tumor vs. normal tissue was validated in two independent sample sets (45 tumors and 11 controls, 43 tumors and 8 controls) using quantitative EpiTyper technology. In tumors, median methylation levels of BCAN, HOXD1, KCTD8, KLF11, NXPH1, POU4F1, SIM1, and TCF7L1 were ≥30% higher than in normal samples, representing potential biomarkers for tumor diagnosis. Using the 90th percentile of methylation levels in normal tissue as cutoff value, 62–92% of in situ samples (n=13), 72–97% of invasive samples from the first validation set (n=32), and 86–100% of invasive samples from the second validation set (n=43) were classified as hypermethylated. Hypermethylation of KLF11 and SIM1 might also be associated with increased risk of developing metastases. In summary, early methylation changes are frequent in the low‐grade pathway of breast cancer and may be useful in the development of differential diagnostic and possibly also prognostic markers.—Faryna, M., Konermann, C., Aulmann, S., Bermejo, J. L., Brugger, M., Diederichs, S., Rom, J., Weichenhan, D., Claus, R., Rehli, M., Schirmacher, P., Sinn, H.‐P., Plass, C., Gerhauser, C. Genome‐wide methylation screen in low‐grade breast cancer identifies novel epigenetically altered genes as potential biomarkers for tumor diagnosis. FASEB J. 26, 4937–4950 (2012). www.fasebj.org

Centrosomal aberrations in primary invasive breast cancer are associated with nodal status and hormone receptor expression

Our purpose was to assess the presence of centrosomal aberrations as measured by immunohistochemistry in primary invasive breast cancer and their association with established and proposed prognostic factors. Tissue sections of 103 primary invasive breast cancers were examined using centrosome‐specific antibodies to pericentrin and γ‐tubulin. At least 3 different tumor regions per case were examined to determine maximum centrosomal aberration levels, which represent the proportion of cells with abnormal centrosomes in the region with the highest percentage of cells with centrosomal aberrations. The χ2 test was performed to evaluate the association of maximum centrosomal aberration levels with patient age; tumor size; nodal status; nuclear grade; hormone receptor and Her2/neu expression; proportion of Ki67‐, p53‐ and Bcl‐2‐positive tumor cells; DNA index; S‐phase fraction; and proliferation index. With pericentrin immunohistochemistry, maximum centrosomal aberration levels >35% were detectable in 92 of the 103 breast carcinomas (89%). We found a highly significant correlation of maximum centrosomal aberration levels above 35% with axillary nodal tumor involvement (p < 0.0001) and the absence of hormone receptors (p < 0.0001). In addition, there was a borderline significant relationship with age <50 years (p = 0.050) and Her2/neu overexpression (p = 0.050). Among node‐negative patients, maximum centrosomal aberration levels >35% were also associated with an increased DNA index (p = 0.006). In a subset of patients, additional staining of centrosomes with a monoclonal anti‐γ‐tubulin antibody essentially confirmed these results. In primary invasive breast cancer, centrosomal aberrations are associated with those factors predicting a more aggressive course of disease. This might indicate a fundamental role of centrosomal dysfunction in disease evolution, possibly as a result of chromosome missegregation during mitosis.

C-myc oncogene amplification in ductal carcinoma in situ of the breast

The c-myc oncogene is frequently activated in invasive breast cancer and has been associated with high nuclear grade, lymph node metastasis and poorer disease outcome. We have examined c-myc oncogene amplification using fluorescence in situ hybridization in a series of 96 pure DCIS. Additionally we assessed amplification and expression of the Her2 and bcl-2 oncogenes. The findings were compared with clinicopathological data, Ki-67 proliferative index and hormone receptor status. We observed c-myc oncogene amplification in 19 tumours (20%). These cases were significantly associated with an average of 38% higher proliferative activity (p = 0.045), a 43% larger tumour size (p = 0.029) and the otherwise rare micropapillary subtype (p = 0.0005). Concluding the c-myc oncogene appears to be involved in the development of a more aggressive phenotype of DCIS.

c-myc Amplifications in primary breast carcinomas and their local recurrences

Objective: To evaluate the role of c-myc oncogene amplifications in the progression of invasive breast carcinomas. Methods: c-myc gene copy number was evaluated in a series of 49 primary breast carcinomas and the corresponding local recurrences using fluorescence in situ hybridisation. Results: 11 of the primary carcinomas (22%) harboured c-myc amplifications; these tumours typically were hormone receptor negative and occurred in younger patients (43 v 53 years). At the time of relapse, six additional tumours had acquired a c-myc amplification. The mean recurrence-free survival was 24 months; c-myc amplified tumours relapsed significantly earlier than carcinomas without amplification (18 v 27 months). Univariate analysis showed a worse overall survival in these patients. Conclusions: While c-myc amplifications can be observed in early stage breast cancer, especially in younger patients, they often occur later in tumour development and appear to be associated with disease progression.