Ulrike Schwarz-Boeger

Large-Scale Association Study Identifies ICAM Gene Region as Breast and Prostate Cancer Susceptibility Locus

We conducted a large-scale association study to identify genes that influence nonfamilial breast cancer risk using a collection of German cases and matched controls and >25,000 single nucleotide polymorphisms located within 16,000 genes. One of the candidate loci identified was located on chromosome 19p13.2 [odds ratio (OR) = 1.5, P = 0.001]. The effect was substantially stronger in the subset of cases with reported family history of breast cancer (OR = 3.4, P = 0.001). The finding was subsequently replicated in two independent collections (combined OR = 1.4, P < 0.001) and was also associated with predisposition to prostate cancer in an independent sample set of prostate cancer cases and matched controls (OR = 1.4, P = 0.002). High-density single nucleotide polymorphism mapping showed that the extent of association spans 20 kb and includes the intercellular adhesion molecule genes ICAM1, ICAM4, and ICAM5. Although genetic variants in ICAM5 showed the strongest association with disease status, ICAM1 is expressed at highest levels in normal and tumor breast tissue. A variant in ICAM5 was also associated with disease progression and prognosis. Because ICAMs are suitable targets for antibodies and small molecules, these findings may not only provide diagnostic and prognostic markers but also new therapeutic opportunities in breast and prostate cancer.

Modulation of CXCR3 ligand secretion by prostaglandin E2 and cyclooxygenase inhibitors in human breast cancer

IntroductionIn murine breast cancer models, the two interferon-gamma (IFN-γ) inducible chemokines and CXC-chemokine receptor 3 (CXCR3) receptor ligands, monokine induced by γ-interferon (CXCL9) and interferon-γ-inducible protein-10 (CXCL10) impair tumor growth and metastasis formation through recruitment of natural killer (NK) cells and tumor-suppressive T lymphocytes. In human breast cancer, CXCL9 mRNA overexpression correlates with the number of tumor infiltrating lymphocytes and predicts response to different chemotherapeutic regimens. Raising the intratumoral CXCR3 ligand concentration is therefore a possible way to enhance immune intervention in breast cancer. Little is known, however, about expression levels and regulation of these chemokines in human breast cancer. Since the inhibition of cyclooxygenases (COX) has been shown to reduce tumor growth and incidence of metastases in a lymphocytic and IFN-γ dependent manner, we argued that COX isoenzymes are a pharmacologic target to increase intratumoral CXCR3 ligand concentration in human breast cancer.MethodsCXCL9 was visualized in breast cancer specimens by immunohistochemistry, expression levels of CXCL9 and cyclooxygenases were determined by ELISA and western blotting, respectively. For regulation studies, Michigan Cancer Foundation-7 (MCF-7) and M.D. Anderson - Metastatic Breast 231 (MDA-MB 231) breast cancer cells were stimulated with IFN-γ with or without prostaglandin E2 (PGE2) or COX inhibitors (indomethacin, acetylsalicylic acid (ASA), celecoxib). CXCR3 ligand release from cells was measured by ELISA.ResultsWithin the tumor microenvironment, cancer cells are the major source of CXCL9. PGE2 impairs IFN-γ mediated CXCL9 and CXCL10 release from MCF-7 and MDA-MB 231 cells, and inhibition of endogenous cyclooxygenases by indomethacin or ASA correspondingly increases this secretion. Otherwise, high concentrations of the Cyclooxygenase-2 (COX-2) specific antagonist celecoxib have opposite effects and impair CXCL9 and CXCL10 release. In human breast cancer tissue specimens there is an inverse correlation between COX-2 overexpression and CXCL9 concentration, suggesting that the observed in vitro effects are of importance in vivo as well.ConclusionsSuppressing endogenous PGE2 synthesis by cyclooxygenase inhibition increases CXCL9 and CXCL10 release from breast cancer cells and is therefore a pharmacologic candidate to enhance intratumoral immune infiltration. Yet, to this end the unselective COX inhibitors ASA and indomethacin seem preferable to celecoxib that at higher concentrations reduces CXCR3 ligand release most probably due to COX independent mechanisms.

Intratumoral Heterogeneity of MicroRNA Expression in Breast Cancer

Profiling studies have identified specific microRNA (miRNA) signatures in malignant tumors including breast cancer. Our aim was to assess intratumoral heterogeneity in miRNA expression levels within primary breast cancers and between axillary lymph node metastases from the same patient. Specimens of 16 primary breast cancers were sampled in 8-10 distinct locations including the peripheral, intermediate, and central tumor zones, as well as two to five axillary lymph node metastases (n = 9). Total RNA was extracted from 132 paraffin-embedded samples, and the expression of miR-10b, miR-210, miR-31, and miR-335 was assessed as well as the reproducibility of RNA extraction and miRNA analysis by quantitative RT-PCR. Considerable intratumoral heterogeneity existed for all four miRNAs within primary breast cancers (CV 40%). No significant differences within (CV 34%) or between different tumor zones (CV 33%) were found. A similar variation in miRNA expression was observed between corresponding lymph node metastases (mean CV 40%). In comparison, the variation among different patients showed a CV of 80% for primary tumors and 103% for lymph node metastases. Both miRNA extraction procedures and quantitative RT-PCR showed high reproducibility (CV ≤ 2%). Thus, the intratumoral heterogeneity of miRNA expression in breast cancers can lead to significant sampling bias. Assessment of breast cancer miRNA profiles may require sampling at several different tumor locations and of several tumor-involved lymph nodes when deriving miRNA expression profiles of metastases.

A Fast, Highly Sensitive and Cheap Tool for Mutation Analysis of Complex Genes

The mutation analysis of complex genes without hot spots for sequence variation is very time consuming and expensive. The aim of our study was to introduce the Denaturing highperformance liquid chromatography (DHPLC) technique into the repertoire of scanning methods for DNA mutations and polymorphisms in the BRCA1 gene. To assess the accuracy of this screening method the analysis was done in parallel with direct sequencing. With 33 fragments we were able to screen the whole coding sequence and exon/intron boundaries of the BRCA1 gene. The comparison of the results revealed that with DHPLC none of the alterations detected by

The benefit using an integrated electronic trial platform for a neoadjuvant therapy trial (HEDON) in primary breast cancer – results of an evaluation study.

CTRC-AACR San Antonio Breast Cancer Symposium: 2008 Abstracts Abstract #3114 Background: At present, academic medical centers conducting investigator initiated trials (IIT) have the choice of relying on paper or going electronic regarding electronic data capture and data management solutions. Many of the electronic systems have originally been developed for requirements of the pharmaceutical industry and all of the currently available systems would thus be isolated in the existing IT setting of the medical centers. We here suggest an approach to integrate a data management system into existing hospital information systems (HIS) and to provide the end users (e.g. physicians, investigators, study nurses) with consolidated user interfaces and integrated systems. Methods: In 2005, a collaboration between the Department of Obstetrics and Gynecology, Klinikum rechts der Isar, Technical University of Munich and Siemens Medical Solutions was initiated as a pilot project. An integrated platform for clinical trials was developed and implemented to support the HEDON trial (Herceptin-Docetaxel-Neoadjuvant), an investigator initiated clinical phase II trial concerning primary systemic therapy of breast cancer. The HEDON trial started in February 2006 and will have recruited all of a total of 90 planned patients in the end of this year. In addition, a translational research trial (TransHEDON) evaluating therapy response markers is an essential component of the clinical trial. Using the integrated platform, clinical data as well as laboratory data are automatically populated from the HIS into the electronical study CRFs, after data confirmation by investigators or study nurses (depending on their defined role) using the validation buffer of the system. The existing PACS and HIS are made accessible from the platform which has special capabilities to greatly improve user interactions with all relevant systems. To quantify the benefit of such an integrated system, an integrated evaluation project was set up including the quantification time savings for all involved personnel. For a pre-defined time period, data capture and data management processes are performed paper based and electronically. This allows thorough and critical analysis of all involved processes Resukts; Errors that occur specially due to manually entering laboratory data can be dramatically minimized using such an electronical data capture system. Another important benefit is time savings. The data will be presented. Conclusion: This single-sign-on electronic platform for clinical trials has been validated in its whole and fulfils the regulatory requirements as specified by GCP or 21 CFR part 11 compliance for trials of the FDA. We consider this integrated system to be very helpful for implementation of clinical trials into a routine hospital setting. Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 3114.

San Antonio Report 2005: Diagnostics, Detection, Proteomics, Nanotechnology, Pathology, Operative Techniques

The San Antonio Breast Cancer Symposium (SABCS), the 28th taking place December 8th-11th 2005 again in San Antonio, TX, USA, has become over the years a leading and essential scientific meeting for state-of-theart breast cancer diagnostics and therapy. In the following selected presentations on new developments and latest aspects in nanotechnology, proteomics, pathology, diagnostics and detection as well as in operative techniques including sentinel lymph node biopsy are described, evaluated and summarized.

Extensive Intraabdominal Metastasis of Inflammatory Breast Cancer

Background: Intraabdominal metastasis is a rare complication of metastatic breast cancer. Case Report: We report a case of extensive intraabdominal metastasis with neurologic symptoms of the left leg in a patient who was treated for breast cancer 2 years before. Diagnosis of metastasis was based on imaging techniques and confirmed by histology. Treatment options were discussed in an interdisciplinary tumor board and chemotherapy with a combination of vinorelbine and capecitabine was initiated. After 3 cycles, the patient showed clinical partial response with reduced tumor volume. Conclusion: An interdisciplinary approach is vital to tailor the best treatment option for the individual patient.