RAD51C – a new human cancer susceptibility gene for sporadic squamous cell carcinoma of the head and neck (HNSCC)

INTRODUCTION: Head and neck squamous cell carcinomas (HNSSCs) are one of the leading causes of cancer-associated death worldwide. Although certain behavioral risk factors are well recognized as tumor promoting, there is very little known about the presence of predisposing germline mutations in HNSCC patients. METHODS: In this study, we analyzed 121 individuals with HNSCCs collected at our institution for germline alterations in the newly identified cancer susceptibility gene RAD51C. RESULTS: Sequencing of all exons and the adjacent introns revealed five distinct heterozygous sequence deviations in RAD51C in seven patients (5.8%). A female patient without any other risk factors carried a germline mutation that disrupted the canonical splice acceptor site of exon 5 (c.706-2A>G). CONCLUSIONS: As there are only a few publications in the literature identifying germline mutations in head and neck cancer patients, our results provide the first indication that paralogs of RAD51, recently described as mutated in breast and ovarian cancer patients, might also be candidates for genetic risk factors in sporadic squamous cell carcinomas of the head and neck

Genome-wide and gene-centric analyses of circulating myeloperoxidase levels in the charge and care consortia

Increased systemic levels of myeloperoxidase (MPO) are associated with the risk of coronary artery disease (CAD). To identify the genetic factors that are associated with circulating MPO levels, we carried out a genome-wide association study (GWAS) and a gene-centric analysis in subjects of European ancestry and African Americans (AAs). A locus on chromosome 1q31.1 containing the complement factor H (CFH) gene was strongly associated with serum MPO levels in 9305 subjects of European ancestry (lead SNP rs800292; P = 4.89 × 10−41) and in 1690 AA subjects (rs505102; P = 1.05 × 10−8). Gene-centric analyses in 8335 subjects of European ancestry additionally identified two rare MPO coding sequence variants that were associated with serum MPO levels (rs28730837, P = 5.21 × 10−12; rs35897051, P = 3.32 × 10−8). A GWAS for plasma MPO levels in 9260 European ancestry subjects identified a chromosome 17q22 region near MPO that was significantly associated (lead SNP rs6503905; P = 2.94 × 10−12), but the CFH locus did not exhibit evidence of association with plasma MPO levels. Functional analyses revealed that rs800292 was associated with levels of complement proteins in serum. Variants at chromosome 17q22 also had pleiotropic cis effects on gene expression. In a case–control analysis of ∼80 000 subjects from CARDIoGRAM, none of the identified single-nucleotide polymorphisms (SNPs) were associated with CAD. These results suggest that distinct genetic factors regulate serum and plasma MPO levels, which may have relevance for various acute and chronic inflammatory disorders. The clinical implications for CAD and a better understanding of the functional basis for the association of CFH and MPO variants with circulating MPO levels require further study

lmmunoreactivity of Thomsen-Friedenreich (TF) antigen in human neoplasms: The importance of carrier-specific glycotope expression on MUC1

On the basis of their known fine specificities we evaluated the immunohistochemical marker qualities of two monoclonal antibodies (mabs) defining the tumor-associated TF disaccharide GalBl-3GalNAc. This antigen is expressed in certain tumors in correlation with prognosis and metastasis. The reactivity of one of these mabs (A78-G/A7) depends on clustered TF disaccharides (glycosylation at vicinal Ser~Thr positions) while the other - rnab BW835 - has been characterized to bind specifically to TF disaccharide linked to a motif within the MUCl repeat. Therefore, rnab BW835 represents an interesting tool for the identification of tumor-associated glycoforms of MUC1, which are involved in tumor progression and metastasis, but also in the recognition of tumor cells by cytotoxic T cells.As references the TF-binding lectins from peanut (PNA) and Artocarpus integrifolia (jacalin) were applied. The binding patterns of these immunoreagents were strikingly distinct. Mab BW835 showed a significantly stronger reactivity than rnab A78-G/A7, especially in gastric, mammary, pancreatic, thyreoideal, renal and bladder carcinomas. PNA and jacalin receptors exhibited an expression in the majority of all cancer types, with the exception of seminoma and glioblastoma/ sarcoma. These results can be explained by the broader fine specificities of the lectins. Furthermore, a strong expression of MUC1-bound TF antigen is indicated by the staining pattern of rnab BW835. The marker qualities of both antigens, TF and MUC1, are combined in the binding specificity of BW835, and hence this antibody may have a high impact for the immunodetection of these tumor-associated antigens

Altered apoptosis and cell cycling of mast cells in bone marrow lesions of patients with systemic mastocytosis

Enhanced expression of the apoptosis-preventing protein bcl-xL and the cell cycle-regulating protein p21 was observed in bone marrow infiltrates of systemic mastocytosis. Expression of bcl-2, Ki67, and p53 as well as ISEL apoptosis staining were comparable in patients with mastocytosis and in controls. An altered rate of apoptosis and cell cycling may contribute to accumulation of mast cells in mastocytosis

Prognostic Significance of a New Grading System of Lymph Node Morphology After Neoadjuvant Radiochemotherapy for Esophageal

Background. Along with primary tumor response, lymph node (LN) status after radiochemotherapy is one of the most important prognostic factors for advanced esophageal carcinoma. We investigated the influence of neoadjuvant radiochemotherapy on histomorphologic parameters of LNs. Methods. One hundred ninety-two patients with esophageal carcinoma underwent surgery after preoperative radiochemotherapy. Response of primary tumor was graded as minor or major. Two matched subgroups were chosen: 20 patients with minor response and 20 patients with major response. Histomorphologic criteria of LNs underwent univariate and multivariate analyses and correlated with tumor response and prognosis statistics. Results. The LNs from 40 patients (N = 1276) were examined (median number of LNs per patient, 31). Of patients with minor response, 65% showed LN metastasis; of those with major response, 20% did so (p = 0.011). Major responders had significantly lower rates of capsular and central fibrosis and vascular transformation and had more sarcoidlike lesions. Logistic regression analysis did not distinguish these parameters between major and minor responders. The 5-year survival rate was 55% for major responders and 10% for minor responders (p = 0.025), 47% for patients with LN metastasis (LNM) and 18% for patients with LNM (p = 0.041). An optimal prognostic factor, LN morphologic grading, was defined as follows: low risk, no LNM and less than 3 LNs with central fibrosis; medium risk, no LNM and central fibrosis in 3 or more LNs or LNM with an LN ratio of less than 0.05; high risk, all other cases. The 5-year survival rate was 56%, 25%, and 0% for patients considered to have low, medium, and high risk, respectively, according to LN morphologic grading (p < 0.003). With the inclusion of this classification in the Cox regression analysis, no other factors showed prognostic relevance. Conclusions. Grading of LN morphology after neoadjuvant radiochemotherapy is the most important prognostic factor for patients with esophageal cancer

DNP‐Supported Solid‐State NMR Spectroscopy of Proteins Inside Mammalian Cells

Elucidating at atomic level how proteins interact and are chemically modified in cells represents a leading frontier in structural biology. We have developed a tailored solid-state NMR spectroscopic approach that allows studying protein structure inside human cells at atomic level under high-sensitivity dynamic nuclear polarization (DNP) conditions. We demonstrate the method using ubiquitin (Ub), which is critically involved in cellular functioning. Our results pave the way for structural studies of larger proteins or protein complexes inside human cells, which have remained elusive to in-cell solution-state NMR spectroscopy due to molecular size limitations

Comparative Quantitative Analysis of Macrophage Populations Defined by CD68 and Carbohydrate Antigens in Normal and Pathologically Altered Human Liver Tissue

Liver macrophages, which are involved in the different types of hepatitis, may indirectly induce hepatic fibrogenesis, since they have the possibility to activate hepatic stellate cells and fibroblasts by secretion of TGF-β , TNF-α and IL-1. To evaluate variations of the number of liver macrophages and their subpopulations, a quantification was carried out in normal human liver tissue, fatty liver, fatty liver hepatitis and hepatitis B. Identification was performed by the mab PG-M1 (anti-CD68) and, comparatively, four lectins, Griffonia simplicifolia agglutinin I (GSA-I), Erythrina cristagalli agglutinin (ECA), peanut agglutinin (PNA) and soybean agglutinin (SBA). A slight decrease in the frequency of macrophages in pericentral fields was observable in fatty liver and fatty liver hepatitis as compared to normal liver tissue. On the other hand, the number of CD68+ cells was significantly enhanced in hepatitis B with moderate and severe inflammatory activity. The highest incidence of macrophages was found in portal tracts of liver with fatty liver hepatitis and, particularly, hepatitis B. The fraction of cells stained by ECA, PNA or SBA did not increase significantly under pathological conditions. In contrast, the percentage of GSA-I binding macrophages was higher in liver parenchyma of hepatitis B and in portal tract macrophages in fatty liver hepatitis and also hepatitis B. In conclusion, our results indicate that GSA-I may aid in the detection of the subpopulation of activated macrophages which are assumed to play a pivotal role in liver pathology