Histology and histopathology Vol.22, nº 9 (2007)

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http://hdl.handle.net/10201/177350

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Open Access
The S100 proteins for screening and prognostic grading of bladder cancer
(Murcia : F. Hernández, 2007) Yao, R.; Davidson, D.D.; López Beltrán, A.; MacLennan, G.T.; Montironi, R.; Cheng, L.
The S100 gene family, which is composed of at least 24 members carrying the Ca2+ binding EF-hand motif, has been implicated in both intracellular and extracellular functions, including enzyme activities, immune responses, cytoskeleton dynamics, Ca2+ homeostasis, cell growth and cell differentiation. Altered S100 protein levels are associated with a broad range of diseases, including cardiomyopathy, inflammatory and immune disorders, neurodegenerative disorders and cancer. Although the precise role of S100 protein in carcinogenesis is poorly understood, it seems that formation of homo- and hetero-dimers, binding of Ca2+ and interaction with effector molecules are essential for the development and progression of many cancers. Several studies have suggested that S100 proteins promote cancer progression and metastasis through cell survival and apoptosis pathways. In animal models of bladder cancer, several S100 proteins are differentially expressed in bladder tumors relative to normal urothelium. In human bladder cancer, overexpression of S100A4, S100A8 or S100A11 are associated with stage progression, invasion, metastasis and poor survival. This review summarizes these findings and evaluates their implications for human bladder cancer management
Open Access
Prenatal corticosterone influences the trajectory of neuronal development, delaying or accelerating aspects of the Purkinje cell differentiation
(Murcia : F. Hernández, 2007) Rugerio-Vargas, C.; Ramírez-Escoto, M.; DelaRosa-Rugerio, C.; Rivas-Manzano, P.
The nervous system developmental programs proceed in orderly fashion following strict timetables. However, the mechanisms regulating developmental timing remain largely unknown. Increases or decreases in glucocorticoids in the fetal brain can be detrimental. We present evidence supporting that corticosterone forwards the migration of cerebellar granule neurons when applied acutely during pregnancy. This change in developmental tempo enhances dendritic growth of Purkinje neurons, increases the nuclear area, accelerates perinucleolar rosette appearance and decreases the development of Nissl bodies. Our observations thus support that forwarding the occurrence of developmental events does not always arrest neuronal growth, as some heterochronic developmental models imply. We suggest that prenatal glucocorticoids alter the trajectory of Purkinje neurons development soon after birth. These changes could represent a transient condition or could produce medium or long-term later consequences. More studies are needed to evaluate these intriguing possibilities
Open Access
Expression pattern of squamous cell carcinoma antigen in oesophageal dysplasia and squamous cell carcinoma
(Murcia : F. Hernández, 2007) Parenti, Anna; Porzionato, A.; Pizzi, S.; Guzzardo, V.; Fassina, G.; Macchi, Verónica; Ninfo, V.; De Caro, Raffaelle
The aim of the present study was to evaluate the tissue expression of squamous cell carcinoma antigen (SCCA) in oesophageal dysplasia and squamous cell carcinoma (SCC) with reference to its clinicopathologic and prognostic significance. Immunohistochemistry using SCCA polyclonal antibody was performed on SCCs from 61 surgical oesophagectomies. Fifteen cases of low-grade dysplasia (LGD) and 37 noncoexistent high-grade dysplasia (HGD) were also sampled from these materials, together with sixteen chronic cases of oesophagitis. SCCA immunoreactivity was present in the maturative compartments of all normal epithelia and oesophagitis. LGDs showed no SCCA immunoreactivity in the dysplastic proliferative component but only in the superficial normal layers. In 94.6% of HGDs, no SCCA immunoreactivity was detected throughout the thickness of the epithelium. In SCCs, SCCA expression higher than 25% was found in 54% of cases. SCCA positivity showed an inverse correlation with histological grade, whereas no statistically significant correlation was found with TNM classifications, stage, or survival. SCCA is not expressed in early oesophageal carcinogenesis but, in SCC, it represents an indicator of histologic differentiation. In differentiated SCC, SCCA may represent a negative factor for cancer invasiveness, through inhibition of proteases
Open Access
Prostate stem cells and cancer
(Murcia : F. Hernández, 2007) Nikitin, Alexander Y.; Matoso, A.; Roy-Burman, P.
Properties shared by neoplastic and stem cells indicate a possibility that somatic stem cells or transit-amplifying cells that have reacquired stem cell properties, particularly the ability for self-renewal, represent favorable targets for malignant transformation. In this review we discuss significance of the stem cell model for understanding prostate cancer pathogenesis and describe relevant studies in animals. It is proposed that dissemination of rare cancer stem cells may lead to metastatic disease and that resistance of such cells to multiple drugs and androgen ablation make them responsible for failure of current treatments. Thus further understanding of the cancer stem cell biology is needed for development of efficient rationally designed therapy permitting better targeting and better treatment outcomes for patients with prostate neoplasms
Open Access
ß-Galactosidase staining on bone marrow. The osteoclast pitfall
(Murcia : F. Hernández, 2007) Kopp, H.G.; Hooper, A.T.; Shmelkov, S.V.; Rafii, S.
The enzyme ß-galactosidase, encoded by the bacterial gene lac-Z, is commonly used as a histochemical reporter to track transplanted cells in vivo or to analyze temporospatial gene expression patterns by coupling expression of specific target genes to ßgalactosidase activity. Previously, endogenous ßgalactosidase activity has been recognized as a confounding factor in the study of different soft tissues, but there is no description of the typical background on bone marrow sections when using the chromogenic substrate 5-Bromo-4-chloro-3-indolyl ß-D-Galactoside (X-Gal). In this report, we show that osteoclasts in bone marrow sections specifically and robustly stain blue with X-Gal. This leads to a typical background when bone marrow is examined that is present from the first day post partum throughout the adult life of experimental mice and can be confused with transgenic, bacterial ßgalactosidase expressing hematopoietic or stromal cells. Experimental variations in the X-Gal staining procedure, such as pH and time of exposure to substrate, were not sufficient to avoid this background. Therefore, these data demonstrate the need for strenuous controls when evaluating ß-galactosidase positive bone marrow cells. Verifiable bacterial ß-galactosidase positive bone marrow cells should be further identified using immunohistological or other approaches. Specifically, ßgalactosidase positive hematopoietic or stromal cells should be proven specifically not to be osteoclasts by costaining or staining adjacent sections for specific markers of hematopoietic and stromal cells.

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