WRAP53 Is Essential for Cajal Body Formation and for Targeting the Survival of Motor Neuron Complex to Cajal Bodies

The WRAP53 protein regulates the formation and maintenance of Cajal bodies (nuclear sub-organelles), as well as directs the recruitment of nuclear factors to Cajal bodies

Autoimmune diseases, asthma and risk of haematological malignancies: A nationwide case-control study in Sweden

To investigate potential associations between several autoimmune diseases and haematological malignancies, we studied 39,908 cases of leukaemia, Hodgkin's disease, non-Hodgkin's lymphoma and myeloma that occurred during 1987-1999 in Sweden, and 149,344 controls. Hospital discharge diagnoses of psoriasis, Sjogren's syndrome, autoimmune haemolytic anaemia, idiopathic thrombocytopenic purpura, pernicious anaemia, multiple sclerosis, rheumatic fever or asthma from 1969 to 1999 were retrieved from the Swedish Hospital Discharge Registry. Psoriasis was positively associated with leukaemia, excluding chronic lymphocytic leukaemia, (odds ratio [OR] = 1.6, 95% confidence interval [CI] 1.1-2.3) and non-Hodgkin's lymphoma (OR = 1.6, 95% CI 1.3-2.1). Sjogren's syndrome increased the risks of all haematological malignancies combined (OR = 4.0, 95% CI 2.3-7.0), and of non-Hodgkin's lymphoma (OR = 6.4, 95% CI 3.5-12). These findings, together with increased risks of several haematological malignancies in autoimmune haemolytic anaemia and idiopathic thrombocytopenic purpura but not in asthma, suggest chronic autoimmunity and immune stimulation as mechanisms contributing to the development of haematological malignancies

Parallel Visualization of Multiple Protein Complexes in Individual Cells in Tumor Tissue

Cellular functions are regulated and executed by complex protein interaction networks. Accordingly, it is essential to understand the interplay between proteins in determining the activity status of signaling cascades. New methods are therefore required to provide information on different protein interaction events at the single cell level in heterogeneous cell populations such as in tissue sections. Here, we describe a multiplex proximity ligation assay for simultaneous visualization of multiple protein complexes in situ. The assay is an enhancement of the original proximity ligation assay, and it is based on using proximity probes labeled with unique tag sequences that can be used to read out which probes, from a pool of probes, have bound a certain protein complex. Using this approach, it is possible to gain information on the constituents of different protein complexes, the subcellular location of the complexes, and how the balance between different complex constituents can change between normal and malignant cells, for example. As a proof of concept, we used the assay to simultaneously visualize multiple protein complexes involving EGFR, HER2, and HER3 homo- and heterodimers on a single-cell level in breast cancer tissue sections. The ability to study several protein complex formations concurrently at single cell resolution could be of great potential for a systems understanding, paving the way for improved disease diagnostics and possibilities for drug development

Identification of new cancer biomarkers based on aberrant mucin glycoforms by in situ Proximity Ligation

Mucin glycoproteins are major secreted or membrane-bound molecules that, in cancer, show modifications in both the mucin proteins expression and in the O-glycosylation profile, generating some of the most relevant tumour markers in clinical use for decades. Thus far, the identification of these biomarkers has been based on the detection of either the protein or the O-glycan modifications. We therefore aimed to identify the combined mucin and O-glycan features, that is, specific glycoforms, in an attempt to increase specificity of these cancer biomarkers. Using in situ proximity ligation assays (PLA) based on existing monoclonal antibodies directed to MUC1, MUC2, MUC5AC and MUC6 mucins and to cancer-associated carbohydrate antigens Tn, Sialyl-Tn (STn), T, Sialyl-Le(a) (SLe(a)) and Sialyl-Le(x) (SLe(x)) we screened a series of 28 mucinous adenocarcinomas from different locations (stomach, ampulla of Vater, colon, lung, breast and ovary) to detect specific mucin glycoforms. We detected Tn/STn/SLe(a)/SLe(x)-MUC1 and STn/SLe(a)/SLe(x)-MUC2 glycoforms in $50% of the cases, with a variable distribution among organs. Some new glycoforms-T/SLe(a)-MUC2, STn/T/SLe(a)/SLe(x)-MUC5AC and STn/T/SLe(a)/SLe(x)-MUC6-were identified for the first time in the present study in a variable percentage of cases from different organs. In conclusion, application of the PLA technique allowed sensitive detection of specific aberrant mucin glycoforms in cancer, increasing specificity to the use of antibodies either to the mucin protein backbone or to the O-glycan haptens alone

Protein expression and cellular localization in two prognostic subgroups of diffuse large B-cell lymphoma: Higher expression of ZAP70 and PKC-beta II in the non-germinal center group and poor survival in patients deficient in nuclear PTEN

Patients diagnosed with diffuse large B-cell lymphoma (DLBCL) show varying responses to conventional therapy, and this might be contributed to the differentiation stage of the tumor B-cells. The aim of the current study was to evaluate a panel of kinases (ZAP70, PKC-beta I and II and phosphorylated PKB/Akt) and phosphatases (PTEN, SHP1 and SHP2) known to be frequently deregulated in lymphoid malignancies. De novo DLBCL cases were divided into two subgroups, the germinal center (GC) group (14/28) and the non-germinal center (non-GC) or activated B-cell (ABC) group (14/28). ZAP70 and PKC-beta II were expressed in a significantly higher percentage of tumor cells in the clinically more aggressive non-GC group compared with the prognostically favourable GC group. Also, the subcellular localization of PKC-beta I and II differed in DLBCL cells, with the PKC-beta I isoform being expressed in both the cytoplasm and nucleus, while PKC-beta II was found exclusively in the cytoplasm. Loss of nuclear PTEN correlated with poor survival in cases from both subgroups. In addition, five cell lines of DLBCL origin were analyzed for protein expression and for mRNA levels of PTEN and SHP1. For the first time, we show that ZAP70 is expressed in a higher percentage of tumor cells in the aggressive non-GC subgroup of DLBCL and that PKC-beta I and II are differently distributed in the two prognostic subgroups of de novo DLBCL

Antagonists of IGF:Vitronectin Interactions Inhibit IGF-I-Induced Breast Cancer Cell Functions

Free to read\ud \ud We provide proof-of-concept evidence for a new class of therapeutics that target growth factor:extracellular matrix (GF:ECM) interactions for the management of breast cancer. Insulin-like growth factor-I (IGF-I) forms multiprotein complexes with IGF-binding proteins (IGFBP) and the ECM protein vitronectin (VN), and stimulates the survival, migration and invasion of breast cancer cells. For the first time we provide physical evidence for IGFBP-3:VN interactions in breast cancer patient tissues; these interactions were predominantly localized to tumor cell clusters and in stroma surrounding tumor cells. We show that disruption of IGF-I:IGFBP:VN complexes with L27-IGF-II inhibits IGF-I:IGFBP:VN-stimulated breast cancer cell migration and proliferation in two- and three-dimensional assay systems. Peptide arrays screened to identify regions critical for the IGFBP-3/-5:VN and IGF-II:VN interactions demonstrated IGFBP-3/-5 and IGF-II binds VN through the hemopexin-2 domain, and VN binds IGFBP-3 at residues not involved in the binding of IGF-I to IGFBP-3. IGFBP-interacting VN peptides identified from these peptide arrays disrupted the IGF-I:IGFBP:VN complex, impeded the growth of primary tumor-like spheroids and, more importantly, inhibited the invasion of metastatic breast cancer cells in 3D assay systems. These studies provide first-in-field evidence for the utility of small peptides in antagonizing GF:ECM-mediated biologic functions and present data demonstrating the potential of these peptide antagonists as novel therapeutics