S100B and neurofibromin immunostaining and X-inactivation patterns of laser-microdissected cells indicate a multicellular origin of some NF1-associated neurofibromas.

Neurofibromatosis 1 (NF1) is an autosomal dominant disease that predisposes individuals to developing benign neurofibromas. Some features and consequences of NF1 appear to result from partial deficiency of neurofibromin (Nfn), the NF1 gene protein product, as a result of haploinsufficiency for the NF1 gene. Other features and consequences of NF1 appear to involve total deficiency of Nfn, which arises as a result of either loss of function of the second NF1 allele or excess degradation of Nfn produced by the second allele in a particular clone of cells.

Different patterns of mast cells distinguish diffuse from encapsulated neurofibromas in patients with neurofibromatosis 1.

Multiple neurofibromas are cardinal features of neurofibromatosis 1 (NF1). Several different types of NF1-associated neurofibromas occur, each distinct in terms of pathological details, clinical presentation, and natural history. Mast cells are present in most neurofibromas and have been shown to be critical to the origin and progression of neurofibromas in both human NF1 and relevant mouse models.

MicroRNA-616 induces androgen-independent growth of prostate cancer cells by suppressing expression of tissue factor pathway inhibitor TFPI-2.

Expression of microRNA genes is profoundly altered in cancer but their role in the development of androgen-independent prostate cancer has received limited attention as yet. In this study, we report a functional impact in prostate cancer cells for overexpression of the microRNA miR-616, which occurred consistently in cells that were androgen-independent (AI) versus androgen-dependent (AD). miR-616 overexpression was confirmed in malignant prostate tissues as opposed to benign prostate specimens.

Lipopolysaccharide-induced epithelial monoamine oxidase mediates alveolar bone loss in a rat chronic wound model.

Reactive oxygen species (ROS) production is an antimicrobial response to pathogenic challenge that may, in the case of persistent infection, have deleterious effects on the tissue of origin. A rat periodontal disease model was used to study ROS-induced chronic epithelial inflammation and bone loss. Lipopolysaccharide (LPS) was applied for 8 weeks into the gingival sulcus, and histological analysis confirmed the onset of chronic disease.

Minimum altered regions in early prostate cancer progression identified by high resolution whole genome tiling path BAC array comparative hybridization.

Background: Carcinoma of the prostate (CaP) is a serious health problem. The altered molecular mechanisms that lead to this disease are poorly understood.

Methods: Specimens from radical prostatectomies and blood were collected from 18 CaP surgery patients.

DNA fingerprinting tags novel altered chromosomal regions and identifies the involvement of SOX5 in the progression of prostate cancer.

Identification of genomic alterations associated with the progression of prostate cancer may facilitate the better understanding of the development of this highly variable disease. Matched normal, premalignant high-grade prostatic intraepithelial neoplasia and invasive prostate carcinoma cells were procured by laser capture microdissection (LCM) from human radical prostatectomy specimens. From these cells, comparative DNA fingerprints were generated by a modified PCR-based technique called scanning of microdissected archival lesion (SMAL)-PCR.

Allele-specific marker generation and linkage mapping on the Xiphophorus sex chromosomes.

There is great interest in the sex chromosomes of Xiphophorus fishes because both WY/YY and XX/XY sex-determining mechanisms function in these species, with at least one taxon possessing all three types of sex chromosomes, and because in certain interspecific hybrids melanoma arises as a consequence of inheritance of the sex-linked macromelanophore determining locus (MDL). Representational difference analysis (RDA) has been used to clone two sequences from the sex-determining region of X. maculatus, including a cholinergic receptor, nicotinic, delta polypeptide (CHRND) orthologue.

The genetic map of Xiphophorus fishes represented by 24 multipoint linkage groups.

Hybrids between distinct Xiphophorus species have been utilized for over 70 years to study melanoma and other neoplasms that can develop spontaneously in hybrid offspring. Genetic linkage mapping has proven to be important in delineating genomic areas that harbor oncogenes and tumor suppressors. Within this report, two parallel backcrosses have been utilized to generate a genetic linkage map for Xiphophorus fishes.

Correlations of EGFR mutations and increases in EGFR and HER2 copy number to gefitinib response in a retrospective analysis of lung cancer patients.

Background: Gefitinib, a small molecule tyrosine kinase inhibitor of the Epidermal Growth Factor Receptor (EGFR), has shown limited efficacy in the treatment of lung cancer. Recognized clinical predictors of response to this drug, specifically female, non-smoker, Asian descent, and adenocarcinoma, together suggest a genetic basis for drug response. Recent studies have addressed the relationship between response and either sequence mutations or increased copy number of specific receptor tyrosine kinases.

Dynamics of expression of growth differentiation factor 15 in normal and PIN development in the mouse.

Growth differentiation factor (GDF15) is a distant member of the transforming growth factor-beta superfamily, a diverse group of structurally related proteins that exert multiple effects on cell fate such as on cell growth and differentiation but little is known about GDF15 in these processes. Previously we observed the mature GDF15 to be associated with human prostate carcinogenesis hence prompting us to study GDF15 further. Here we report gdf15 expression both at the RNA and protein levels, in normal prostatic tissues of wild type (wt) and prostatic intraepithelial neoplasia (PIN) of transgenic (Tg) 12T-7s model mice during embryonic, postnatal, and adult prostate formation up to 15 weeks after birth.

The significance of LMO2 expression in the progression of prostate cancer.

LIM domain only 2 (LMO2) proteins are important regulators in determining cell fate and controlling cell growth and differentiation. This study has investigated LMO2 expression in human prostatic tissue specimens, prostate cancer cell lines, and xenografts; and has assessed the possible role and mechanism of LMO2 in prostate carcinogenesis. Immunohistochemical analysis on a tissue microarray consisting of 91 human prostate specimens, including normal, prostatic hyperplasia, high-grade prostatic intraepithelial neoplasia, and invasive carcinoma, revealed that overexpression of LMO2 was significantly associated with advanced tumour stage, as measured by Gleason score (p = 0.

Protein profiling of microdissected prostate tissue links growth differentiation factor 15 to prostate carcinogenesis.

Identification of proteomic alterations associated with early stages in the development of prostate cancer may facilitate understanding of progression of this highly variable disease. Matched normal, high-grade prostatic intraepithelial neoplasia (hPIN) and prostate cancer cells of predominantly Gleason grade 3 were procured by laser capture microdissection from serial sections obtained from snap-frozen samples dissected from 22 radical prostatectomy specimens. From these cells, protein profiles were generated by surface-enhanced laser desorption/ionization-time of flight mass spectrometry.

Comparative structure and characterization of a CDKN2 gene in a Xiphophorus fish melanoma model.

We have cloned, sequenced, and characterized the RNA expression properties of a fish CDKN2 gene from Xiphophorus helleri and X. maculatus. This gene, termed CDKN2X, shows a high degree of amino acid sequence similarity to members of the mammalian CDKN2 gene family, which includes the tumor suppressor loci CDKN2A (P16) and CDKN2B (P15).

The Xiphophorus-derived antibody, XMEL, shows sensitivity and specificity for human cutaneous melanoma but is not a prognostic marker.

XMEL is a monoclonal antibody raised against part of the extracellular domain of the putative tyrosine kinase receptor protein implicated in the pathogenesis of melanoma formation in the Xiphophorus fish melanoma model. Our objective in this study was to determine the diagnostic and prognostic utility of XMEL for human melanoma. Formalin-fixed tissue from 82 melanomas, 42 carcinomas, 23 neural tumors, 12 lymphomas and 12 sarcomas were immunostained with XMEL and compared with a widely used melanoma antibody, HMB-45.

The melanoma-specific XMEL antigen is expressed in dysplastic naevi.

We have previously shown that a novel monoclonal antibody, XMEL, exhibited reactivity with deep primary melanomas while showing no reactivity with other tumours and normal tissue. XMEL was raised against a part of the extracellular domain of Xmrk, a growth factor receptor presumed to mediate melanoma formation in the Xiphophorus fish model. Here we investigate the range of XMEL immunohistochemical reactivity in paraffin sections from human common acquired and dysplastic naevi of both junctional and compound type.

Generation of poly- and mono-clonal antibodies against trout fibronectin (FN) and their use in FN immunodetection in teleost fishes.

Immunization of rats with gelatin-affinity column purified fibronectin (FN) from rainbow trout (Oncorhynchus mykiss) plasma produced a polyclonal antiserum that reacts specifically with FN in immunoblotted protein extracts and cultured cells, not only from trout but also from swordtails (Xiphophorus helleri). Most importantly, this antiserum specifically stains FN-containing structures in sections from embryos, as well as skin and dorsal fin of swordtails and platyfish (Xiphophorus maculatus), allowing, e.g.

Differences in transcription and promoters of Xmrk-1 and Xmrk-2 genes suggest a role for Xmrk-2 in pigment pattern development in the platyfish, Xiphophorus maculatus.

Pigment (macromelanophore) patterns in the platyfish Xiphophorus maculatus are due to a complex pigmentary locus; for example, the spotted-dorsal (Sd) fin pattern is due to the Sd locus. In interspecific backcross hybrids with the swordtail X. helleri, the Sd pattern changes into benign or malignant dorsal fin melanoma as a result of hemi- or homozygous loss of a platyfish regulatory (R) gene, the tumor suppressor gene Diff, that appears to play a role in the final differentiation of macromelanophores.

Relationship between variant forms of estrogen receptor RNA and an apoptosis-related RNA, TRPM-2, with survival in patients with breast cancer.

Background: Although smaller variant forms of estrogen receptor (ER) messenger RNA (mRNA) have been detected in breast tumors, neither their prevalence nor their prognostic significance have been evaluated. Similarly, TRPM-2 mRNA, the product of a gene induced principally during the onset of apoptosis, is present in mouse and human breast cancer cell lines, but whether it also occurs in primary breast tumors and is related to disease outcome is unknown.

Methods: The relative expression and transcript size of ER mRNA and TRPM-2 mRNA in 126 primary breast tumors were measured by Northern analysis and compared with tumor grade, hormone receptor status, extent of tumor necrosis, and survival.

A putative marker for human melanoma. A monoclonal antibody derived from the melanoma gene in the Xiphophorus melanoma model.

A MoAb was raised against a peptide corresponding to an exposed domain of the putative tyrosine kinase receptor protein encoded by Xmrk, a gene involved in melanoma formation and/or progression in the Xiphophorus fish melanoma model. The antibody reacts specifically with cells from human melanocytic lesions, ie, common acquired nevi, primary and metastatic melanoma biopsies. No reactivity with other cells, including normal melanocytes, was observed in the biopsies or with cells in biopsies from normal tissue (skin, liver, lung, spleen) and from other malignancies including those of neuroectodermal origin.

Functional analysis and temporal expression of promoter regions from fish antifreeze protein genes in transgenic Japanese medaka embryos.

Several series of sequences that are upstream of the transcriptional start site of different types of fish AFP genes were fused to the bacterial CAT gene, and their transcriptional role was examined in a transient expression assay after microinjection into Japanese medaka (Oryzias latipes) embryos at the 1-4 cell stage. Our studies demonstrated that the AFP genes have functional promoter regions containing positive as well as negative regulatory regions, indicating that these genes could be regulated at multiple sites. We also observed a promoter-specific pattern of temporal expression.

Transient expression of foreign DNA during embryonic and larval development of the medaka fish (Oryzias latipes).

Species of small fish are becoming useful tools for studies on vertebrate development. We have investigated the developing embryo of the Japanese medaka for its application as a transient expression system for the in vivo analysis of gene regulation and function. The temporal and spatial expression patterns of bacterial chloramphenicol acetyltransferase and galactosidase reporter genes injected in supercoiled plasmid form into the cytoplasm of one cell of the two-cell stage embryo was promoter-specific.

Explanted Fish Neural Tubes Give Rise to Differentiating Neural Crest Cells: (neural crest cell culture/pigment cells/Xiphophorus/medaka/fish).

Neural tubes were explanted from the trunk of various embryonic stages of three teleost fish, Xiphophorus maculatus (platyfish), X. helleri (swordtail), and Oryzias latipes (Japanese medaka) with the aim to obtain in vitro differentiating neural crest cells. Outgrowth of cells was observed immediately after attachment of the explants on dishes coated with fibronectin.

Distribution and migration pathways of HNK-1-immunoreactive neural crest cells in teleost fish embryos.

Whole mounts and cross-sections of embryos from three species of teleost fish were immunostained with the HNK-1 monoclonal antibody, which recognizes an epitope on migrating neural crest cells. A similar distribution and migration was found in all three species. The crest cells in the head express the HNK-1 epitope after they have segregated from the neural keel.

Stable lines of transgenic zebrafish exhibit reproducible patterns of transgene expression.

To study the frequency of germ-line transformation and to examine the reproducibility of tissue-specific transgene expression, we produced several lines of transgenic zebrafish expressing a recombinant chloramphenicol acetyltransferase (CAT) gene. Supercoiled plasmids containing both Rous sarcoma virus and SV-40 promoter sequences upstream of the CAT coding region were injected into zebrafish embryos prior to first cleavage. CAT activity could be detected in batches of injected embryos as early as 8 h and up to at least 12 days post-fertilization.