Histology and histopathology Vol.24, nº8 (2009)
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- PublicationOpen AccessImproved methodology for the detection and quantification of the acrosome reaction in mouse spermatozoa(Murcia : F. Hernández, 2009) Lybaert, Pascale; Danguy, A.; Leleux, Fabienne; Meuris, Sylvain; Lebrun, PhilippeThis study evaluates the use of two fluorescein-labelled (FITC) plant lectins, Pisum sativum (edible pea) agglutinin (PSA) and Arachis hypogaea (peanut) agglutinin (PNA), in order to determine the most accurate and reliable method to experimentally detect and assess the acrosome reaction in mouse spermatozoa. PNA-FITC labelling was restricted to the acrosome and was not influenced by the fixation procedure; either absolute methanol or paraformaldehyde. In contrast, PSA-FITC not only labelled the acrosome, but also the whole head and the flagellum. This aspect was especially marked after methanol fixation. The cytoplasmic droplet, when present, was also stained by PSA-FITC. Incubation with the calcium ionophore ionomycin induced a concentration and time-dependent increase in the number of acrosome reactions. Compared to spotted preparations, smear samples exhibited a high proportion of spermatozoa with damaged acrosome. In conclusion, PNA-FITC labelling was more accurate than PSA-FITC labelling to detect the acrosome of mouse spermatozoa. The fixation method (methanol vs. paraformaldehyde) had no influence on the staining pattern of PNA-FITC labelling, but spotted preparations are recommended to avoid mechanical damage to the acrosome. Ionophore challenge confirmed the existence of a calcium-dependent acrosome reaction in mouse spermatozoa and validated the use of PNA-FITC to quantify this physiological process. The present study illustrates important methodological considerations which need to be taken into account in order to design a reliable and reproducible protocol for the study of the acrosome reaction.
- PublicationOpen AccessExpression of hexokinases and glucose transporters in treated and untreated oesophageal adenocarcinoma(Murcia : F. Hernández, 2009) Fonteyne, Philippe; Casneu, Veerle; Pauwels, Patrick; Van Damme, Nancy; Peeters, Marc; Dierckx, Rudi; Van de Wiele, ChristopheThe aim of this study was to assess the expression pattern of the high glucose affinity glucose transporters GLUT 1, 2, 3, 4, 8 and 9 and of hexokinases I, II and III in newly diagnosed oesophageal adenocarcinoma by means of immunohistochemistry. Twenty patients eligible to undergo primary surgery and 18 patients with incomplete pathological response following induction radio chemotherapy, all suffering from oesophageal adenocarcinoma, were included in the study. The intensity and amount of positive tumour cells in the immuno-reaction (histology score (Hscore)) for GLUT 1, 3, 4, 8 and 9 as well as for hexokinase I, II and III were assessed independently by two experienced observers, blinded to the clinical results. In patients that underwent primary surgery, Hscores of GLUT8 (µ 6.7; sd3.3) and GLUT1 (µ 5.5; sd: 5.3) were significantly higher than Hscores of GLUT9 (µ 2.2; sd 1.5) and GLUT3 (µ 3.2, sd: 2.5). Hscores of hexokinase I (µ : 8.3; sd: 4.3), II (µ 5.5, sd: 4.0) and III (Ì 1.5, sd: 0.7) were all significantly different from each other (p<0.04). In patients that underwent radiochemotherapy prior to surgical tumour resection, µ Hscores were 6.9 (sd: 4.4) for GLUT1, 6.8 (sd: 5.3) for GLUT3, 5.9 (sd: 4.2) for GLUT8, 3.4 for GLUT9 (sd: 2.7) and 2.3 (sd: 3.6) for GLUT 4. Hscores of GLUT1 and GLUT3 were significantly higher than Hscores of GLUT4. Finally, Hscores of patients with radiochemotherapy for GLUT3, hexokinase II and III were significantly higher when compared to patients that underwent primary surgery.
- PublicationOpen AccessTumor cell expression of podoplanin correlates with nodal metastasis in esophageal squamous cell carcinoma(Murcia : F. Hernández, 2009) Chuang, Wen-Yu; Yeh, Chi-Ju; Wu, Yi-Chin; Chao, Yin-Kai; Liu, Yun-Hen; Tseng, Chen-Kan; Chang, Hsien-Kun; Liu, Hui-Ping; Hsueh, ChuenPodoplanin is a mucin-like glycoprotein expressed in the lymphatic endothelium. It has been suggested to play a role in lymphangiogenesis, since podoplanin deficient mice were found to have dilated malfunctioning lymphatic vessels and lymphedema. High podoplanin expression in tumor cells was found to correlate with lymph node metastasis and poor clinical outcome in patients with oral squamous cell carcinoma (SCC). However, the prognostic significance of podoplanin expression in esophageal SCC remains unexplored. Herein, we studied podoplanin expression in 59 patients who underwent surgical resection of esophageal SCC, with 43 of them preceded by preoperative concurrent chemoradiotherapy (CCRT). We found that high podoplanin expression strongly correlated with clinical nodal metastasis (cN1; p=0.0063), which was associated with short survival (p=0.012). However, there was no direct association between high podoplanin expression and short survival. We also found that lymphatic vessel invasion in the resected esophagus was strongly associated with pathological nodal metastasis (pN1; p=0.00092). Our results suggest that podoplanin could also play a role in tumor aggressiveness in esophageal SCC, as well as in oral SCC.
- PublicationOpen AccessCytoplasmic inclusions of TDP-43 in neurodegenerative diseases: A potential role for caspases(Murcia : F. Hernández, 2009) Rohn, Troy T.TAR DNA-binding protein-43 (TDP-43) proteinopathies are classified based upon the extent of modified TDP-43 inclusions and include a growing number of neurodegenerative diseases including amyotrophic lateral sclerosis (ALS), frontotemporal lobar degeneration with ubiquitin immunoreactive, tau negative inclusions (FTLD-U) and FTLD with motor neuron disease (FTLD-MND). In addition, TDP-43 inclusions have also been identified in a number of other neurodegenerative disorders including Alzheimer’s disease, corticobasal degeneration, Lewy body related diseases and Pick’s disease. Current understanding suggests that in these diseases, TDP-43 is relocated from the nucleus to the cytoplasm and sequestered into inclusions that contain modified TDP-43. Major modifications of TDP-43 have been identified as being hyperphosphorylation and proteolytic cleavage by caspases. In this review a summary of the major findings regarding the proteolytic modification of TDP-43 will be discussed as well as potential toxic-gain mechanisms these fragments may cause including cytoskeletal disruptions.
- PublicationOpen AccessVaspin and amylin are expressed in human and rat placenta and regulated by nutritional status(Murcia : F. Hernández, 2009) Caminos, Jorge E.; Bravo, Susana B.; Garcés, Maria F.; González, C. Ruth; Cepeda, Libia A.; González, Adriana C.; Nogueiras, Rubén; Gallego, R.; Garcia-Caballero, Tomas; Cordido, Fernando; López, Miguel; Diéguez, C.Amylin (islet amyloid polypeptide) and vaspin (visceral adipose tissue specific serpin) are gut and adipocyte hormones involved in the regulation of body weight homeostasis. The aim of this study was to examine whether amylin and vaspin are expressed in human and rat placenta, as well as their regulation by nutritional status. Our results demonstrate that amylin and vaspin are localized in both human and rat placenta. In the rat term placenta vaspin was demonstrated in the trophoblast of the fetal villi, the labyrinth. Vaspin immunostaining in human placenta was localized in cytotrophoblast and syncytiotrophoblast in the first trimester placentas while in the third trimester vaspin was localized in the syncytiotrophoblast. Regarding amylin, rat placenta of 16 days of gestational age showed an intense immunostaining, mainly localized in the labyrinth. On the other hand, in the human third trimester placenta amylin immunoreactivity was intense in the syncytiotrophoblast of the chorionic villi and in decidual cells. Furthermore, placental amylin and vaspin showed an opposite pattern of expression during pregnancy, with vaspin showing the highest expression level at the end and amylin at the beginning of pregnancy. Finally, food restriction also has contrary effects on their expression, increasing vaspin but decreasing amylin placental mRNA and protein levels. Taken together, our results demonstrate that vaspin and amylin are modulated by energy status in the placenta, which suggests that these proteins may be involved in the regulation of placental metabolic functions.
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