Distribution of IGFBP-rP1 in normal human tissues.

IGFBP-rP1/mac25 is a recently described member of the insulin-like growth factor binding protein (IGFBP) family. It has structural homology to the other members of the IGFBP family but has a lower affinity for insulin-like growth factors (IGFs). In previous studies using RNA blot hybridization, it was shown that the expression of IGFBP-rP1/mac25 was ubiquitous in normal human tissues. In this report we show by immunohistochemistry that the expression of IGFBP-rP1/mac25 is actually restricted to certain organs and specific cell types. We used an antibody raised against a decapeptide of the C-terminal part of the protein that recognizes a approximately 37-kD protein under reduced conditions. The immunohistochemistry performed on normal human tissues showed a ubiquitous intense staining of peripheral nerves and a variable degree of positive staining in smooth muscle cells, including those from blood vessel walls, gut, bladder, and prostate. Cilia from the respiratory system, epididymis, and fallopian tube showed intense immunoreactivity. Most endothelial cells showed some positivity, whereas fat cells, plasma cells, and lymphocytes were negative. There was specific expression limited to certain cell types in the kidney, adrenal gland, and skeletal muscle, indicating a possible specialized function of IGFBP-rP1/mac25 in these organs. We further noted an opposite pattern of staining in the lining epithelium of breast (typically positive) and prostate glands (largely negative). The specific localization of IGFBP-rP1/mac25 as described implies a function of the protein. However, its regulation within the IGF axis or a possible direct action of IGFBP-rP1/mac25 remains to be demonstrated.     

The distribution of collagenase in normal rat tissues.

A rabbit monospecific anti-rat uterus collagenase antibody has been used to study the distribution of collagenase in normal rat tissues by immunohistochemical methods. Indirect staining was performed with fluorescein-conjugated goat anti-rabbit immunoglobulin G antibody. The organs studied were brain, lung, myocardium, liver, spleen, kidney, adrenal, testes, uterus, xiphoid cartilage, tail tendon, skeletal (triceps) muscle and skin. Collagenase is widely present throughout the connective tissue structures in all organs examined. The enzyme is apparently bound to collagen fibers, reticulum fibers and basement membranes. The results suggest that control of collagenase activity depends on factors other than the presence of the enzyme in tissues.     

Characterization of serine palmitoyltransferase in normal human tissues.

Sphingolipids serve as structural elements of cells and as lipid second messengers. They regulate cellular homeostasis, mitogenesis, and apoptosis. Sphingolipid signaling may also be important in various pathophysiologies such as vascular injury, inflammation, and cancer. Serine palmitoyltransferase (SPT) catalyzes the condensation of serine with palmitoyl-CoA, the first, rate-limiting step in de novo sphingolipid biosynthesis. This integral microsomal membrane protein consists of at least two subunits, SPT1 and SPT2. In this study we analyzed the expression of SPT1 and SPT2 in normal human tissues. Strong SPT1 and SPT2 expression was observed in pyramidal neurons in the brain, in colon epithelium, and in mucosal macrophages. However, SPT2 expression was more prominent than SPT1 in the colon mucosal macrophages, the adrenomedullary chromaffin cells and endothelium, and in the uterine endothelium. SPT2 was localized in both nuclei and cytoplasm of the adrenomedullary chromaffin cells, whereas SPT1 was primarily cytoplasmic. These observations link enhanced SPT expression to proliferating cells, such as the lung, stomach, intestinal epithelium, and renal proximal tubular epithelium, and to potentially activated cells such as neurons, chromaffin cells, and mucosal macrophages. A baseline expression of SPT, established by this study, may serve as a measure for aberrant expression in various disease states.     

Nuclear phosphoprotein kinase activities in normal and neoplastic tissues.

Nuclear phosphoprotein kinases from normal rat liver and transplantable neoplasms were fractionated and compared. A phosphoprotein kinase fraction activated by Mn2+ was found to be present only in the neoplasms. This nuclear protein kinase phosphorylated nuclear proteins represented by one major and several minor bands as determined by polyacrylamide gel electrophoresis (M approximately 50,000).     

Characterization of matriptase expression in normal human tissues.

Matriptase is a type II transmembrane serine protease that has been implicated in the progression of epithelium-derived tumors. The role of this protease in the biology of normal epithelial cells remains to be elucidated. Matriptase mRNA has been detected by Northern analysis in tissues rich in epithelial cells, and the protein is expressed in vivo in normal and cancerous breast, ovarian, and colon tissues. However, a systematic analysis of the distribution of matriptase protein and mRNA in normal human tissues rich in epithelium has not been reported. In this study we characterized the expression of the protease in a wide variety of normal human tissues using a tissue microarray and whole tissue specimens. Significant immunoreactivity and mRNA expression were detected in the epithelial components of most epithelium-containing tissues. Matriptase expression was found in all types of epithelium, including columnar, pseudostratified columnar, cuboidal, and squamous. Distinct spatial distributions of reactivity were observed in the microanatomy of certain tissues, however. This suggests that although matriptase is broadly expressed among many types of epithelial cells, its activity within a tissue may be regulated in part at the protein and mRNA levels during the differentiation of selected epithelia.     

Haymaker gene expression in malignant and normal gynecologic tissues.

We previously reported that cell lines established from human carcinomas and leukemias/lymphomas expressed high levels of an intracellular membrane-bound protein, Haymaker, whereas cell lines derived from non-malignant connective tissue cells and lymphoid cells expressed low levels of this gene product. To determine whether these findings reflect neoplastic transformation or, alternatively, tissue specificity, we examined by immunohistochemical and molecular methods the expression of Haymaker in gynecologic organs with and without tumor. A highly specific, affinity-purified rabbit polyclonal antibody against a 25-mer Haymaker peptide was used for immunohistochemical staining and morphometric analysis of 85 tissue specimens. Immunohistochemical studies demonstrate, for the first time, that Haymaker protein is highly expressed in epithelial cells of the endometrium of the normal uterus and to a somewhat lesser extent in the mucosa of the normal vagina and cervix, but is poorly expressed or absent in cells of the connective tissue and smooth muscle strata of these organs (p < 0.005). Significant differences in Haymaker expression, as assessed by immunohistochemistry, between malignant and normal gynecologic tissues were not observed (p = 0.27). The expression of Haymaker protein does not appear, therefore, to be a marker of malignant transformation of the epithelium of gynecologic organs but rather distinguishes both normal and malignant epithelial cells from normal connective tissue and smooth muscle cells.     

Superoxide dismutase in normal and malignant tissues in different species.

1. Superoxide dismutase (superoxide: superoxide oxido-reductase, E.C. 1.15.1.1) in different species was determined quantitatively and qualitatively. Although quantitative differences were minor, there were significant differences in the isoenzyme patterns among the species. 2. No quantitative differences were found in superoxide dismutase (SOD) activities in the brains of mice between 1 and 23 days of age. The mitochondrial isoenzyme increased with age, attaining maximal levels between 9 and 12 days. In the six, regions of adult rat brain studied, highest values of SOD were found in the hypothalamus and lowest in the cortex. 3. SOD levels generally were lower in several transplantable mouse and rat tumors than in normal tissues of these species. Mn-SOD was not detected in the tumors studied by the methods employed.     

Structural differences in ferritins from normal and malignant rat tissues.

Ferritins purified from several normal and malignant rat tissues were examined for amino acid composition, content of tryptic peptides, available sulfhydryl groups and subunit sizes and proportion. Ferritin extracted from adult kidney, neonatal liver and hepatic and renal tumors differed from the ferritin of adult rat liver in migration on electrophoretic gels and in antibody affinity, but did not differ among themselves. Nevertheless, they showed distinctive differences in amino acid composition and tryptic peptide content. All of them and also adult liver ferritin contained two major species of subunits differing in molecular weight. The proportions of subunits, and the available sulfhydryl groups of the intact ferritin molecules, differed among these tissue ferritins. On the basis of amino acid and peptide content, the ferritins of hepatomas and the renal tumor analyzed showec the greatest similarity but not identity. The ferritin of neonatal liver was next most similar. Kidney ferritin differed considerably in composition from tumor and neonatal ferritins, while adult liver ferritin was the most extremely divergent of the series examined. A similar progressive difference was found on examining the proportions of subunits and sulfhydryl groups in these ferritins. However, changes in subunit proportion cannot explain the amino acid and peptide compositional changes.     

Distribution of CIAPIN1 in normal fetal and adult human tissues.

CIAPIN1, a newly identified antiapoptotic molecule that plays an essential role in mouse definitive hematopoiesis, is considered a downstream effector of the receptor tyrosine kinase-Ras signaling pathway. Our previous studies have indicated that CIAPIN1 is involved in the development of multidrug resistance (MDR) in gastric cancer cells. However, the mechanism of CIAPIN1-mediated antiapoptosis and MDR has not been fully elucidated. To reveal the possible physiological role of CIAPIN1, we examined the expression and distribution of CIAPIN1 in fetal and adult human tissues using immunohistochemistry. We found that CIAPIN1 was ubiquitously distributed in fetal and adult tissues, and was localized in both the cytoplasm and the nucleus. The expression patterns of CIAPIN1 were similar in fetal and adult tissues, and was correlated with the previously described expression pattern of p21ras. These observations suggest that CIAPIN1 expression appears to be involved in cell differentiation, and that it might exert universal and possibly important physiological functions under the regulation of Ras in humans.     

Expression of PDE11A in normal and malignant human tissues.

Cyclic nucleotide phosphodiesterase 11A (PDE11A) is the newest member in the PDE family. Although the tissue distribution of PDE11A mRNA has been shown, its protein expression pattern has not been well studied. The goal of this report is to investigate the distribution of PDE11A proteins in a wide range of normal and malignant human tissues. We utilized a polyclonal antibody that recognized all four PDE11A isoforms. Its specificity was demonstrated by Western blot analysis on a recombinant human PDE11A protein and native PDE11A proteins in various human tissues. Immunohistochemistry showed that PDE11A is widely expressed. Various degrees of immunoreactivity were observed in the epithelial cells, endothelial cells, and smooth muscle cells of all tissues examined. The highest expression was in the epithelial, endothelial, and smooth muscle cells of the prostate, Leydig, and spermatogenic cells of the testis, the tubule epithelial cells in the kidney, the epithelial and endothelial cells in the adrenal, the epithelial cells and macrophages in the colon, and the epidermis in the skin. Furthermore, PDE11A expression was also detected in several human carcinomas. Our results suggest that PDE11A might be involved in multiple physiological processes in various organs via its ability to modulate intracellular cAMP and cGMP levels.     

Retinoid-induced apoptosis in normal and neoplastic tissues

Vitamin A and its derivatives (collectively referred to as retinoids) are required for many fundamental life processes, including vision, reproduction, metabolism, cellular differentiation, hematopoesis, bone development, and pattern formation during embryogenesis. There is also considerable evidence to suggest that natural and synthetic retinoids have therapeutical effects due to their antiproliferative and apoptosis-inducing effects in human diseases such as cancer. Therefore it is not surprising that a significant amount of research was dedicated to probe the molecular and cellular mechanisms of retinoid action during the past decade. One of the cellular mechanisms retinoids have been implicated in is the initiation and modulation of apoptosis in normal development and disease. This review provides a brief overview of the molecular basis of retinoid signaling, and focuses on the retinoid-regulation of apoptotic cell death and gene expression during normal development and in pathological conditions in vivo and in various tumor cell lines in vitro.     

Galectin-4 in normal tissues and cancer

Galectin-4 belongs to a subfamily of galectins composed of two carbohydrate recognition domains within the same peptide chain. The two domains have all the conserved galectin signature amino acids, but their overall sequences are only approximately 40% identical. Both domains bind lactose with a similar affinity as other galectins, but their respective preferences for other disaccharides, and larger saccharides, are distinctly different. Thus galectin-4 has a property of a natural cross-linker, but in a modified sense since each domain prefers a different subset of ligands. Similarly to other galectins, galectin-4 is synthesized as a cytosolic protein, but can be externalized. During development and in adult normal tissues, galectin-4 is expressed only in the alimentary tract, from the tongue to the large intestine. It is often found in relatively insoluble complexes, as a component of either adherens junctions or lipid rafts in the microvillus membrane, and it has been proposed to stabilize these structures. Strong expression of galectin-4 can be induced, however, in cancers from other tissues including breast and liver. Within a collection of human epithelial cancer cell lines, galectin-4 is overexpressed and soluble in those forming highly differentiated polarized monolayers, but absent in less differentiated ones. In cultured cells, intracellular galectin-4 may promote resistance to nutrient starvation, whereas—as an extracellular protein—it can mediate cell adhesion. Because of its distinct induction in breast and other cancers, it may be a valuable diagnostic marker and target for the development of inhibitory carbohydrate-based drugs. Published in 2004. This revised version was published online in July 2006 with corrections to the Cover Date.