A Reliable Stem Cell Carrier: An Experimental Study in Wistar Rats.

INTRODUCTION: Treatments based on cell biology need reliable and precise carriers for reaching the desired targets. For that reason, a PDO-based cell carrier was idealized, with the purpose of carrying stem cells to distant sites at room temperature. MATERIALS AND METHODS: Three modalities of the same carrier were evaluated: one containing undifferentiated human dental pulp stem cells (DPSCs); one loaded with stem cells induced to neurogenic differentiation (DPSCNs); and one without cells (Blank). The carriers were implanted in sciatic nerve gaps in 48 Wistar rats that were divided in three groups. Two other rats were included in a SHAM control group. Immunohistochemical, histological and clinical analyses were performed in two, four, six and eight weeks of time. RESULTS: Efficacy of human stem cell transportation at room temperature to rats was attested. Moreover, it was possible to confirm that those cells show tropism for inflamed environments and are also prone to induction of neurogenesis in the first two weeks, vanishing after that period. CONCLUSION: Clinical evaluation of the animals' gait recovery shows a promising perspective of success with the inclusion of stem cell-loaded PDO tubes in nerve gaps, which may be positively compared to previously published studies. NO LEVEL ASSIGNED: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors - www.springer.com/00266.

The Profile of Heparanase Expression Distinguishes Differentiated Thyroid Carcinoma from Benign Neoplasms.

INTRODUCTION: The search for a specific marker that could help to distinguish between differentiated thyroid carcinoma and benign lesions remains elusive in clinical practice. Heparanase (HPSE) is an endo-beta-glucoronidase implicated in the process of tumor invasion, and the heparanase-2 (HPSE2) modulates HPSE activity. The aim of this study was to evaluate the role of heparanases in the development and differential diagnosis of follicular pattern thyroid lesions. METHODS: HPSE and HPSE2 expression by qRT-PCR, immunohistochemistry evaluation, western blot analysis and HPSE enzymatic activity were evaluated. RESULTS: The expression of heparanases by qRT-PCR showed an increase of HPSE2 in thyroid carcinoma (P = 0.001). HPSE activity was found to be higher in the malignant neoplasms than in the benign tumors (P<0.0001). On Western blot analysis, HPSE2 isoforms were detected only in malignant tumors. The immunohistochemical assay allowed us to establish a distinct pattern for malignant and benign tumors. Carcinomas showed a typical combination of positive labeling for neoplastic cells and negative immunostaining in colloid, when compared to benign tumors (P<0.0001). The proposed diagnostic test presents sensitivity and negative predictive value of around 100%, showing itself to be an accurate test for distinguishing between malignant and benign lesions. CONCLUSIONS: This study shows, for the first time, a distinct profile of HPSE expression in thyroid carcinoma suggesting its role in carcinogenesis.