Characteristics of Leiomyosarcoma: Induction of Hematogenous Metastasis by Isolated Uterine Mesenchymal Tumor Stem-like Cells.

Background/aim: Uterine leiomyosarcoma (Ut-LMS) is a refractory tumor that repeatedly recurs with hematogenous metastasis, which may be due to the presence of drug-resistant tumor stem cells. Its treatment is limited to surgical procedures. We previously reported that Ut-LMS spontaneously developed in mice deficient in the proteasome component low-molecular mass polypeptide 2 (LMP2).

Characterization of Leiomyomatoid Angiomatous Neuroendocrine Tumour (LANT)-like Tumour in the Myometrium with Histopathological Examination.

Leiomyomatoid angiomatous neuroendocrine tumour (LANT) is possibly a new disease entity that was reported as a dimorphic neurosecretory tumour with a leiomyomatous vascular component; it was found in the pituitary. We describe uterine LANT-like malignant tumour in a 45-year-old woman with uterine mesenchymal tumour, diagnosed clinically as uterine leiomyoma. She underwent laparoscopic myomectomy.

Molecular Pathology and Novel Clinical Therapy for Uterine Leiomyosarcoma.

Patients with uterine leiomyosarcoma (LMS) typically present with vaginal bleeding, pain, and a pelvic mass, with atypical presentations of hypercalcemia and eosinophilia also being reported. Radiographic evaluation with combined positron-emission tomography/computed tomography may assist in diagnosis and surveillance in women with uterine LMS; these are commonly used with stage and tumour grade as prognostic indicators and a recently developed risk-assessment index to predict disease-specific survival. Recent studies have shown that the addition of adjuvant therapy after surgical management does not seem to improve survival, and ovarian preservation does not appear to negatively impact outcome.

Development of unique antibodies directed against each of the six different phosphotyrosine residues within the T cell receptor CD3ζ chain.

Signal transduction from the T cell antigen receptor (TCR)/CD3 complex involves six different immunoreceptor tyrosine-based activation motifs (ITAM) located within the cytoplasmic tails of the CD3 chains. Each ITAM possesses two conserved tyrosine residues that can undergo phosphorylation upon TCR/CD3 crosslinking and become a docking site for SH2-containing effector molecules. Specificity of the SH2 domains is determined by their ability to bind a phosphorylated tyrosine in the context of a longer peptide motif within the target protein.

Antibody arrays--an emerging tool in cancer proteomics.

Cancer is a result of complex changes that occur in normal cells as they transform to become malignant and further when they become metastatic. These changes are not a consequence of a single protein but rather involve multiple proteins that function in pathways and networks. Thus, profiling cancer-associated changes requires simultaneous measurement of many proteins in a single sample.

Melanoma cells exhibit strong intracellular TASK-3-specific immunopositivity in both tissue sections and cell culture.

Amplification of the kcnk9 gene and overexpression of the encoded channel protein (TASK-3) seems to be involved in carcinogenesis. In the present work, TASK-3 expression of melanoma cells has been studied. For the investigation of TASK-3-specific immunolabelling, a monoclonal antibody has been developed and applied along with two, commercially available polyclonal antibodies targeting different epitopes of the channel protein.

Panorama Ab Microarray Cell Signaling kit: a unique tool for protein expression analysis.

Antibody arrays are a promising new tool for mass analysis of protein level changes in cells responding to different stimuli. Here we describe a novel antibody array system called Panorama Ab Microarray Cell Signaling, that contains 224 antibodies spotted on FAST nitrocellulose-coated slides that can detect protein levels as low as a few nanograms per mL. The antibodies spotted are specific for proteins important in various areas of cell signaling such as phosphorylation, cell cycle, apoptosis, nuclear signaling and cytoskeleton proteins.

Analyzing the role of the putative inositol 1,3,4,5-tetrakisphosphate receptor GAP1IP4BP in intracellular Ca2+ homeostasis.

Inositol 1,3,4,5-tetrakisphosphate (IP(4)) has been linked to a potential role in the regulation of intracellular free Ca(2+) concentration ([Ca(2+)](i)) following cellular stimulation with agonists that activate phosphoinositide-specific phospholipase C. However, despite many studies, the function of IP(4) remains unclear and indeed there is still some debate over whether it has a function at all. Here we have used various molecular approaches to address whether manipulation of the potential IP(4) receptor, GAP1(IP4BP), affects [Ca(2+)](i) following cellular stimulation.

Regulation of S33/S37 phosphorylated beta-catenin in normal and transformed cells.

A novel phosphorylation-specific antibody (alphapbeta-catenin) was generated against a peptide corresponding to amino acids 33-45 of human beta-catenin, which contained phosphorylated serines at positions 33 and 37. This antibody is specific to phosphorylated beta-catenin and reacts neither with the non-phosphorylated protein nor with phosphorylated or non-phosphorylated plakoglobin. It weakly interacts with S33Y beta-catenin but not with the S37A mutant.

Detection of partially phosphorylated forms of ERK by monoclonal antibodies reveals spatial regulation of ERK activity by phosphatases.

When cells are stimulated by mitogens, extracellular signal-regulated kinase (ERK) is activated by phosphorylation of its regulatory threonine (Thr) and tyrosine (Tyr) residues. The inactivation of ERK may occur by phosphatase-mediated removal of the phosphates from these Tyr, Thr or both residues together. In this study, antibodies that selectively recognize all combinations of phosphorylation of the regulatory Thr and Tyr residues of ERK were developed, and used to study the inactivation of ERK upon mitogenic stimulation.

Detection of ERK activation by a novel monoclonal antibody.

The mitogen-activated protein kinase, ERK is activated by a dual phosphorylation on threonine and tyrosine residues. Using a synthetic diphospho peptide, we have generated a monoclonal antibody directed to the active ERK. The antibody specifically identified the active doubly phosphorylated, but not the inactive mono- or non- phosphorylated forms of ERKs.

Natural autoantibodies in sera of patients with Gaucher's disease.

Gaucher's disease (GD) is associated with hyperactivity of the immune system, which manifests by polyclonal hypergamma-globulinemia and an increased incidence of monoclonal gammopathies in GD patients. We analyzed sera of 43 patients with GD for the presence of autoantibodies against 14 autoantigens. The results demonstrated a significant increase in the incidence of all autoantibodies tested, ranging from 11% for anti-RNP, pyruvate dehydrogenase (PDH), and DNA antibodies to 57% for rheumatoid factor.

Antimitochondrial (pyruvate dehydrogenase) antibodies in leprosy.

Sera from 69 patients with leprosy but without liver involvement were assayed for the presence of mitochondrial pyruvate dehydrogenase (PDH)-specific autoantibodies by enzyme-linked immunoabsorbent assay (ELISA), immunoblotting using PDH as an antigen and by enzymatic inhibition test. Twenty-seven of the leprosy serum samples (39.1%) were found to react with PDH by ELISA.

A rheumatoid factor transgenic mouse model of autoantibody regulation.

To address whether B cells expressing a disease-associated autospecificity are regulated in normal mice, we have established a rheumatoid factor (RF) transgenic model of autoimmunity, using V genes derived from an IgA anti-IgG2a RF isolated from an autoimmune MRL/lpr mouse. As we wished to study induction of tolerance during B cell development, we cloned the VH gene into an IgM expression vector. The RF we chose binds only IgG2a of the 'a' allotype (IgG2a) but not IgG2ab allowing us to produce transgenic animals on IgHa and IgHb backgrounds, which either express or lack the self-antigen.

Quantitative analysis of bone marrow thymic progenitors in young and aged mice.

Our studies on the capacity of bone marrow (BM) to generate T lymphocytes in aging have revealed that under the competitive conditions of thymic reconstitution, cells of aged mice are significantly inferior to those of the young. The present study was designed to further investigate the basis of this age-related change. Two mechanisms were considered: (a) The potential of BM-derived T cell precursors from aged mice to proliferate and differentiate in the thymic microenvironment is impaired.

Altered VH gene segment utilization in the response to phosphorylcholine by aged mice.

Newly generated bone marrow B cell precursors of aged BALB/c mice, stimulated in splenic fragment cultures, display a markedly increased frequency of phosphorylcholine (PC)-responsive cells. This increased frequency is found for both precursors that utilize VHS107, a phenotype common to essentially all PC-specific B cells of young mice, and, surprisingly, for precursors that utilize VH genes other than VHS107. PC-specific hybridomas derived from bone marrow cells of aged mice utilize members of at least three VH gene segment families that have never been observed in PC responses of young mice.

The role of IL-4 in the generation of B lymphocytes in the bone marrow.

It has been indicated that IL-4 supports the maturation of pre-B cells to B lymphocytes. The present study was designed to investigate the mechanism by which IL-4 influences this maturational process. In order to determine whether IL-4 acts directly on pre-B cells, we sorted out B220+, sIg- cells from bone marrow of young adult (C3H X C57BL/6)F1 mice.

Age-related changes in the capability of the bone marrow to generate B cells.

The capability of the bone marrow (BM) to generate new B cells in aging was studied in vitro. BM cells from old (26 to 30 mo) or young (3 mo) BALB/c and (C3H/eB x C57BL/6)F1 mice were depleted of mature B cells and these surface Ig (sIg) BM cells were incubated in culture for 3 days. The frequency of newly generated B cells in these cultures was determined by assessing the frequency of slg+ cells and of B cells forming colonies in agar and by assaying the proliferative capacity of these newly generated B cells after stimulation by LPS.

Age-related changes in the capacity of bone marrow cells to differentiate in thymic organ cultures.

The capacity of the bone marrow to give rise to T cells in advanced age was studied in vitro by reconstituting fetal thymic lobes from 14-day C57BL/Ka (Thy-1.1) mice with bone marrow cells from old (24-month) or young (3-month) C57BL/6 (Thy-1.2) mice.

Ontogeny of T cells: development of pre-T cells from fetal liver and yolk sac in the thymus microenvironment.

The patterns of development of T cells from the very early stem cells that settle in the embryonic thymus have been studied. For this purpose, mouse embryonic thymuses (14 days) depleted of thymocytes were reconstituted with hemopoietic stem cells from fetal liver (FL) and yolk sac (YS) and T-cell development was followed in vitro in organ culture. It was found that cells derived from FL and YS of 10- to 14-day-old embryos were capable of reconstituting depleted thymic explants and exhibiting membrane markers in a pattern similar to that of thymocytes developing in intact thymic explants.

T cell involvement in the decrease of antigen-responsive B cells in aged mice.

The role of T cells in the reduced frequency of splenic B cells specific for several antigens in aged mice was studied by assessing B cell responsiveness in (a) aged nude mice and (b) irradiated young mice repopulated with splenic B cells or with Ig- bone marrow cells from young mice and T cells from aged vs. young mice. Using the fragment culture technique to assess B cells specific for 2,4-dinitrophenyl (DNP) and for (4-hydroxy-3,5-dinitrophenyl) acetyl, we found that the frequency of responsive splenic B cells in aged BALB/c nude mice was very similar to that of young nude mice.

The frequency and fine specificity of B cells responsive to (4-hydroxy-3-nitrophenyl)acetyl in aged mice.

The B-cell response to NP-Hy of two murine strains has been analyzed in order to evaluate the affects of aging on B-cell repertoire expression. The results indicate that for both BALB/c mice (Igha) and B10.D2 mice (Ighb) the frequency of (4-hydroxy-3-nitrophenyl)acetyl (NP)-responsive splenic B cells is approximately twofold lower, on a per B cell basis, in aged mice as compared to young adults.