Rab3a and Rab27b Expression in Nonfunctioning Pituitary Adenomas

Patients with nonfunctioning pituitary adenoma (NFPA) have normal circulating levels of anterior pituitary hormones. Here we examined the expression of exocytic trafficking regulators, Rab27b and Rab3a, in surgically resected pituitary adenoma tissues by immunohistochemical (IHC) analysis using anti-Rab27b and anti-Rab3a antibodies. Among the examined tissues, just over half of the null-cell adenomas and one-third of the gonadotropin-producing adenomas were immunonegative for both Rab27b and Rab3a. However, no Rab-negative samples were observed among the functioning adenomas. These results suggested that downregulated Rab protein expression in anterior pituitary endocrine cells could underlie, at least in part, the hormone-secretion defects of nonfunctioning adenoma cells. Rab27b, Rab3a, and their cellular regulators might therefore be promising pathological markers of patients with NFPA

Proteomic Profiling of Thyroid Papillary Carcinoma

Papillary thyroid carcinoma (PTC) is the most common endocrine malignancy. We performed shotgun liquid chromatography (LC)/tandem mass spectrometry (MS/MS) analysis on pooled protein extracts from patients with PTC and compared the results with those from normal thyroid tissue validated by real-time (RT) PCR and immunohistochemistry (IHC). We detected 524 types of protein in PTC and 432 in normal thyroid gland. Among these proteins, 145 were specific to PTC and 53 were specific to normal thyroid gland. We have also identified two important new markers, nephronectin (NPNT) and malectin (MLEC). Reproducibility was confirmed with several known markers, but the one of two new candidate markers such as MLEC did not show large variations in expression levels. Furthermore, IHC confirmed the overexpression of both those markers in PTCs compared with normal surrounding tissues. Our protein data suggest that NPNT and MLEC could be a characteristic marker for PTC

Functional tooth restoration by next-generation bio-hybrid implant as a bio-hybrid artificial organ replacement therapy

Bio-hybrid artificial organs are an attractive concept to restore organ function through precise biological cooperation with surrounding tissues in vivo. However, in bio-hybrid artificial organs, an artificial organ with fibrous connective tissues, including muscles, tendons and ligaments, has not been developed. Here, we have enveloped with embryonic dental follicle tissue around a HA-coated dental implant, and transplanted into the lower first molar region of a murine tooth-loss model. We successfully developed a novel fibrous connected tooth implant using a HA-coated dental implant and dental follicle stem cells as a bio-hybrid organ. This bio-hybrid implant restored physiological functions, including bone remodelling, regeneration of severe bone-defect and responsiveness to noxious stimuli, through regeneration with periodontal tissues, such as periodontal ligament and cementum. Thus, this study represents the potential for a next-generation bio-hybrid implant for tooth loss as a future bio-hybrid artificial organ replacement therapy

Expression of Keratin 75 (K6hf) in Oral Squamous Cell Carcinoma

Cytokeratin is commonly used diagnostic markers of oral squamous cell carcinoma (OSCC). Especially, Keratin17 (K17) is reported to be up-regulated in OSCC. Recently, identification and quantification of proteins from tissue section become possible by using laser microdissection and LC/MS/MS method. In this study, we performed nano-flow liquid chromatography, mass spectrometry and protein identification by tandem mass spectrometry (LC/MS/MS) analysis on pooled protein extracts from OSCC tissue section and compared the results with those from normal epithelium. As a result, Keratin 6hf is considered as a candidate marker of OSCC. From more validation, the expression of K6hf may be associated with malignancy of oral epithelial lesion. In previous study, K6hf is known to be specifically expressed in a hair follicle and specifically cross a partner with K17. But, there are no report about correlation between K6hf and carcinoma. In conclusion, K6hf expression may play an important role in the carcinogenesis progression of OSCC. However, further studies on the molecular function of K6hf are encouraged to clear the precise mechanism of K6hf in OSCC

Coordination of Cellular Dynamics Contributes to Tooth Epithelium Deformations.

The morphologies of ectodermal organs are shaped by appropriate combinations of several deformation modes, such as invagination and anisotropic tissue elongation. However, how multicellular dynamics are coordinated during deformation processes remains to be elucidated. Here, we developed a four-dimensional (4D) analysis system for tracking cell movement and division at a single-cell resolution in developing tooth epithelium. The expression patterns of a Fucci probe clarified the region- and stage-specific cell cycle patterns within the tooth germ, which were in good agreement with the pattern of the volume growth rate estimated from tissue-level deformation analysis. Cellular motility was higher in the regions with higher growth rates, while the mitotic orientation was significantly biased along the direction of tissue elongation in the epithelium. Further, these spatio-temporal patterns of cellular dynamics and tissue-level deformation were highly correlated with that of the activity of cofilin, which is an actin depolymerization factor, suggesting that the coordination of cellular dynamics via actin remodeling plays an important role in tooth epithelial morphogenesis. Our system enhances the understanding of how cellular behaviors are coordinated during ectodermal organogenesis, which cannot be observed from histological analyses

The regulation of the tooth morphogenesis via actin reorganization.

<p><b>(A)</b> The localizations of p-cofilin (green, left upper), cofilin (green, left lower), and F-actin (white, right) were detected by immunohistochemistry. The G0/G1 phase cells (red, center) are visualized with a Fucci probe. The lingual side is on the left in all panels. <b>(B)</b> Estimations of the p-cofilin/cofilin ratios in parts of the tooth germ epithelium (EK, enamel knot; DL, dental lamina; B and L, buccal side and lingual sides of the growing apex of the epithelium). The relative amounts of cofilin and p-cofilin in the regions of the epithelium were determined by immunoblotting (left). The intensities of the bands were calculated and are indicated in the bar graphs (right). <b>(C)</b> Measurements of actin dynamics in the epithelium using fluorescence recovery after photobleaching (FRAP). The right graph illustrates the best-fit curves of the normalized fluorescence intensity during the FRAP assay. The spots indicate the half-recovery times. <b>(D)</b> Gene expression of upstream molecules that regulate cofilin activity in the E14.5 tooth germ. The lingual side is on the left in all panels. The scale bars represent 100 μm. <b>(E)</b> Inhibition of cell proliferation by cofilin phosphorylation in a WST-8 assay. The results are presented as the mean ± s.d. of triplicate experiments. *<i>P</i> < 0.01, analyzed by <i>t</i>-test. LIMK WT, wild-type LIM-kinase (LIMK); LIMK D460A, dominant negative LIMK mutant; Rac V12, dominant active mutant of Rac1. <b>(F)</b> Inhibition of cell migration by cofilin phosphorylation in a wound healing assay. The bars indicate the migration distances of the epithelial cells. The results are presented as the mean ± s.d. of triplicate experiments. *<i>P</i> < 0.01, analyzed by <i>t</i>-test. <b>(G)</b> Schematic summarizing the observed results in this study.</p