Managing Difficulties of Microsatellite Instability Testing in Endometrial Cancer-Limitations and Advantages of Four Different PCR-Based Approaches.

Microsatellite instability (MSI), a common alteration in endometrial cancers (EC) is known as a biomarker for immune checkpoint therapy response alongside screening for Lynch Syndrome (LS). However, former studies described challenging MSI profiles in EC hindering analysis by using MSI testing methods intensively validated for colorectal cancer (CRC) only. In order to reduce false negatives, this study examined four different PCR-based approaches for MSI testing using 25 EC samples already tested for mismatch repair deficiency (dMMR).

Detection of HPV subtypes by mass spectrometry in FFPE tissue specimens: a reliable tool for routine diagnostics.

Aims: Human papilloma virus (HPV) infection is a causative agent for approximately 5% of all new cancer cases in humans. The virus is detected in cervical, anal, vaginal, penile, vulvar and head and neck cancers and has prognostic implications. Thus, test systems are required to detect high-risk but also low-risk HPV subtypes with high specificity and sensitivity in a time-effective and cost-effective manner.

Expression of miR-146a, miR-155, and miR-223 in formalin-fixed paraffin-embedded synovial tissues of patients with rheumatoid arthritis and osteoarthritis.

Rheumatoid arthritis (RA) is a chronic autoimmune disease with a heterogeneous clinical presentation affecting about 1 % of adults in developed countries. Currently, the diagnosis is based on the revised criteria of the American College of Rheumatology (ACR) and the European League Against Rheumatism (EULAR) from 2010. These criteria include clinical and laboratory parameters.

Detection of KRAS, NRAS and BRAF by mass spectrometry - a sensitive, reliable, fast and cost-effective technique.

Background: According to current clinical guidelines mutational analysis for KRAS and NRAS is recommended prior to EGFR-directed therapy of colorectal cancer (CRC) in the metastatic setting. Therefore, reliable, fast, sensitive and cost-effective methods for routine tissue based molecular diagnostics are required that allow the assessment of the CRC mutational status in a high throughput fashion.

Methods: We have developed a custom designed assay for routine mass-spectrometric (MS) (MassARRAY, Agena Bioscience) analysis to test the presence/absence of 18 KRAS, 14 NRAS and 4 BRAF mutations.

The urokinase-system--role of cell proliferation and apoptosis.

The serine protease urokinase-type plasminogen activator (uPA) and its receptor (uPAR) are involved in the control of extracellular matrix turnover, cell migration, invasion and cell signalling leading to a variety of different responses, under both physiological and pathological conditions. The urokinase receptor, binding to the growth factor-like domain of uPA, directs membrane-associated extracellular proteolysis and signals through transmembrane proteins, thus regulating tissue regeneration, angiogenesis, cancer growth and metastasis. Since these physiological and patho-physiological processes of the uPA-system are known, less informations concerning uPA-induced cell proliferation and anti-apoptotic effects of the uPA-system are available.

The expression of metastasis suppressor MIM/MTSS1 is regulated by DNA methylation.

MIM/MTSS1 was initially described as a gene missing in invasive bladder cancer cell lines. Functional analysis revealed that MIM is an actin binding protein involved in the regulation of actin cytoskeleton dynamics. MIM was shown to be sonic hedgehog (Shh) signaling dependent and synergizes with the effects of Gli transcription factors.

The coincidence of chromosome 15 aberrations and beta2-microglobulin gene mutations is causative for the total loss of human leukocyte antigen class I expression in melanoma.

Purpose: Total loss of surface presentation of human leukocyte antigen (HLA) class I molecules, protecting tumor cells from the recognition by cytotoxic host CD8+ T cells, is known to be caused by mutations in the beta2-microglobulin (beta2m) gene. We asked whether abnormalities of chromosome 15, harboring the beta2m gene on 15q21, in addition to beta2m gene mutations, are causative for the HLA class I-negative phenotype of melanoma cells.

Experimental Design: To answer this, we established primary cell lines from the beta2m-negative metastatic melanoma tissues of four different patients and analyzed them for beta2m gene mutations and chromosome 15 aberrations, the latter by loss of heterozygosity analysis, fluorescence in situ hybridization (FISH), and multicolor FISH.

Urokinase-type plasminogen activator induces proliferation in breast cancer cells.

Urokinase-type plasminogen activator (uPA) is implicated in various pathophysiological processes, including extracellular matrix turnover, cell migration and invasion. Our study aimed to determine the role of uPA in both proliferation and mitogen-activated protein kinase (MAPK) pathway. Hence, we analyzed the effects induced by exogeneous addition of domain-specific uPA antibodies and uPA-interacting molecules on proliferation of uPA-suppressed MDA-MB-231 breast cancer cells.

Dual FISH analysis of benign and malignant tumors of the salivary glands and paranasal sinuses.

To date, the underlying genomic changes in benign and malignant tumors of salivary-gland and paranasal-sinus origin are poorly understood. This is due in part to the low incidence of these tumors and the enormous histological variety of tumors within this head and neck region. We examined 58 of these tumors (14 adenoid cystic carcinomas, 9 adenocarcinomas, 5 cylindrical carcinomas, 11 pleomorphic adenomas, and 19 inverted papillomas) by dual fluorescence in situ hybridization (FISH) with centromere-specific probes on six chromosomes (3, 7, 9, 11, 17, and 18) for numerical changes.

HER2/neu, p53, Ki67, and hormone receptors do not change during neoadjuvant chemotherapy in breast cancer.

The selection of a systemic breast cancer therapy is based on the expression pattern of immunohistochemical prognostic markers. In our study we sought to determine whether neoadjuvant chemotherapy may alter these expression patterns within the tumors. Our hypothesis was that the expression of the immunohistochemical prognostic markers does not differ between tissue specimens before and after neoadjuvant chemotherapy.

In vitro suppression of urokinase plasminogen activator in breast cancer cells--a comparison of two antisense strategies.

High level expression of urokinase plasminogen activator (uPA) has been well documented in a variety of tumors. In breast cancer, expression of uPA is essential for tumor cell invasion, metastasis and proliferation. By contrast, the primary objective of tumor therapy is to reduce the uPA expression level within the tumor, which results in abrogation of proliferation, invasion and metastasizing of the tumor cells.

Intratumoral genomic heterogeneity in primary head and neck cancer and corresponding metastases detected by dual-FISH.

Intratumoral genomic heterogeneity, which can be defined as both intersample and intrasample heterogeneity, is still a poorly understood phenomenon in head and neck squamous cell carcinoma (HNSCC) with presumed implications on tumor behavior and even prognosis. We analyzed 89 tumor specimen from 37 HNSCC patients by fluorescence in situ hybridization (dual-FISH) using specific DNA probes binding to centromeric sites of 6 chromosomes to investigate intratumoral heterogeneity. A derivation from disomy in at least 1/6 chromosomes was detected in 88/89 (99%) specimen.