Histology and histopathology Vol.24,nº11 (2009)

Ir a Estadísticas

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http://hdl.handle.net/10201/177692

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Open Access
Temporal and spatial distribution of TGF-B isoforms and signaling intermediates in corneal regenerative wound repair
(Murcia : F. Hernández, 2009) Huh, Man-IL; Chang, Yongmin; Jung, Jae-Chang
The present study analyzed the temporal and spatial expression of TGF-ß isoforms and activated pSmad2 and p38MAPK during epithelial debridement wound repair, using chick cornea by immunohistochemistry. Normal corneas showed low-level TGFßs staining. Following wounding, TGF-ß1 expression was strong in the Bowman’s layer (BL). TGF-ß3 expression was confined to basal cells in the regenerating and unwounded regions, and was not detected in migrating epithelial, stromal or endothelial cells. In addition, TGF-ß3 treatment stimulated the proliferation of cultured epithelial cells. Our present findings seem to suggest that the TGF-ß3 signal may be required for epithelial cell proliferation. TGF-ß2 expression was strong in migrating and proliferating epithelial cells, many active migrating fibroblasts at the wound edge, endothelial cells and Descemet’s membrane (DM). Although both nuclear pSmad2 and p38MAPK staining was observed in many basal epithelial cells, pSmad2 positive cells were co-localized with PCNA positive cells. Therefore, it seems likely that the pSmad2 signal may affect epithelial cell proliferation in healing corneas. Both pSmad2 and p38MAPK expression were also observed in endothelial cells. Interestingly, many active fibroblasts over the whole stroma in early wound healing at day 2 expressed nuclear pSmad2, but little if any cytoplasmic p38MAPK. Collectively, temporal/spatial up-regulation and distribution of the three TGF-ß isoforms, as well as concerted activation of both Smad2 and p38MAPK, appears to be a key aspect of regenerative corneal wound healing in the chick.
Open Access
FOXP1 status in splenic marginal zone lymphoma, a fluorescence in situ hybridization and immunohistochemistry approach
(Murcia : F. Hernández, 2009) Baró, Cristina; Espinet, Blanca; Salido, Marta; Colomo, Lluis; Luño, Elisa; Florensa, Lourdes; Ferrer, Ana; Salar, Antonio; Campo, Elías; Serrano, Sergi; Solé, Francesc
Splenic marginal zone lymphoma (SMZL) is a well-recognized entity in which chromosomal aberrations seem to be potential markers in diagnosis, prognosis and disease monitoring. FOXP1 is a transcriptional regulator of B lymphopoiesis that is deregulated in some types of NHL. Translocation t(3;14)(p14;q32) has been described in marginal zone lymphomas but few series have studied FOXP1 involvement in SMZL. We performed cytogenetic, fluorescence in situ hybridization (FISH) and immunohistochemical (IHC) studies in a series of 36 patients in order to study the status of FOXP1 in this entity. According to our results, FOXP1 is not rearranged in SMZL, although we were able to demonstrate gains of FOXP1 gene due to trisomy 3/3p by FISH. FOXP1 protein expression seemed to be not related to any aberration and IHC studies are not conclusive.
Open Access
Hepatocyte nuclear factor-1B(HNF-1B) in human urogenital organs, Its expression and role in embryogenesis and tumorigenesis
(Murcia : F. Hernández, 2009) Kato, Noriko; Motoyama, Teiichi
Molecules responsible for embryogenesis are often involved in tumorigenesis. Recent exhaustive cDNA microarray analyses in human neoplasms expanded knowledge of such molecules. Hepatocyte nuclear factor-1ß (HNF-1ß) is a homeobox transcription factor that functions as a homodimer or heterodimer with HNF-1a. In contrast to HNF-1a, HNF-1ß is very weakly expressed in the liver and is commonly expressed in the kidneys. During human embryonic stage, HNF-1ß plays an important role in organogenesis, especially of the urogenital system. In the human fetus, HNF-1ß expression is common in mesonephric duct derivatives and metanephros (permanent kidneys). HNF-1ß germline mutations cause malformations of these structures. Recent microarray analyses have disclosed that HNF-1ß is aberrantly up-regulated in clear cell carcinoma of the ovary, which is a carcinoma of müllerian nature, but which was initially misnamed “mesonephroma”. HNF-1ß is also expressed in ovarian endometriosis, which is a probable origin of clear cell carcinoma. On the other hand, HNF-1ß is downregulated in renal neoplasms, such as chromophobe cell carcinoma. In this review, we first summarize HNF-1ß expression in the developing urogenital system of the human embryo. Then, we describe the HNF-1ß status in human urogenital neoplasms and discuss its role in tumorigenesis.
Open Access
Lymphatic spread of mesenchymal renal tumor to metastatic parathymic lymph nodes in rat
(Murcia : F. Hernández, 2009) Rozsa, David; Trencsenyi, Gyorgy; Kertai, Pal; Marian, Terez; Nagy, Gabor; Banfalvi, Gaspar
Rat mesenchymal renal tumor cells (NeDe) transplanted under the kidney capsule of F344 rats resulted in metastases in the parathymic lymph nodes. Tumor cells were isolated from these tumor-bearing lymph nodes and 106 cells were implanted under the kidney capsule. Tumor growth after this implantation could be traced within six days. India ink was implanted to prove that there is a connection between the lymphatic vessels of the kidney capsule and the parathymic lymph nodes. The distribution of the radioligand 18FDG in different organs also provided evidence that the parathymic lymph nodes are the primary sites of metastatic tumor growth. Tumor growth was followed after staining sections of biopsies of normal, tumorous kidneys and parathymic lymph nodes embedded in paraffin. The progression of tumor formation was seen as a frontline between the healthy and tumor bearing tissue. This demarcation line was sharp at the beginning of the invasion and at the peripheral regions of the tumor, while the central region infiltrated into the healthy kidney tissue. The initial invasion gradually turned to an infiltration resulting in the disruption of the renal tissue, especially at the periphery. Accumulation of lipids and flow of blood to the lymphatic vessels was due to the lack of angiogenesis, leading to an increased pressure of the interstitial fluid. Interstitial damage ultimately led to the appearance of blood and the growth of tumor cells in parathymic lymph nodes. The kidney capsule-parathymic lymph node complex is proposed as a suitable metastatic model for the isolated in vivo examination of tumor development and for the analysis of secondary tumors.
Open Access
Staining patterns of keratins in the human urinary tract
(Murcia : F. Hernández, 2009) Alonso, Angélica; Ikinger, Uwe; Kartenbeck, Jürgen
The keratins, members of the intermediate filament family, are characteristically expressed in epithelial cells. In the various types of epithelia, the keratin expression pattern is characterized by cell-type specific combinations of the keratin isotypes with a plain pattern in monolayered (simple) epithelia and more complex patterns in stratified and pseudostratified epithelia. Here we demonstrate that the transitional epithelium of the human urinary tract holds an exceptional position between the pseudostratified and stratified epithelia. We show that the simple epithelia keratins 7, 8, 18 and 19 are expressed throughout the whole epithelium as known from pseudostratified epithelia. In addition, we demonstrate expression of keratins 5, 14 and 17, otherwise present in basal cells of multilayered epithelia, and keratins 4 and 13, present in suprabasal areas of non cornified multilayered epithelia. Moreover, we report differences in expression in the various morphological parts of the urinary tract which might be related to their specific functions. Keratin 20, a typical component of the simple epithelia of the digestive tract, is present in bladder and ureter but not in the renal pelvis. Keratin 6, typical for stratified epithelia, is found only in parts of the renal pelvis. We further show that changes in keratin pattern occur during the development from embryonic to adult bladder urothelium. In contrast to adult tissue, the simple type keratins 7, 8 and 18 are not synthesized in basal embryonic cells. Further, keratin 20, present in cells facing the bladder lumen in adult urothelium, is expressed in all but the basal cells in embryonic bladder.

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