Anti-LAMP2 monoclonal antibody, clone M3/84 [Biotin]

Malfunction of polycystin 1 (PC1) is linked to abnormally high epithelial cell proliferation and fluid secretion, eventually leading to renal cyst development and declined renal function as found in autosomal dominant polycystic kidney disease (ADPKD). Currently, there is no effective therapy for ADPKD. Recent studies report PC1 regulates CFTR chloride channels and beta-catenin levels in normal renal epithelial cells. Concurrently, our previous study found steviol retarded renal cyst enlargement in an in vitro and in an in vivo models by reducing CFTR expression and activity. Therefore, a potential relationship between steviol and PC1 is worthy of exploration. The present study was aimed to determine the effect of steviol on PC1, CFTR, and beta-catenin levels in renal epithelial cells with defective PC1 biogenesis and expression (Prkcsh(-/-) cell) and postnatal Pkd1 homozygous cell (Pkd1(-/-) cells). Using western blot analysis, it was found that steviol treatment at 100 mu M for 24-48 h substantially enhanced and stabilized PC1 C-terminal expression, while decreasing CFTR and beta-catenin protein expression in both Prkcsh(-/-) and Pkd1(-/-) cells. In addition, steviol promoted LAMP2 expression, a lysosomal enzyme marker. Interestingly, hydroxychloroquine (a lysosome inhibitor) treatment abolished steviol's effect in reducing CFTR and beta-catenin protein expression. Taken together, these findings suggest steviol slows cyst progression in cells and animal models of PKD, in part, by enhancing and stabilizing PC1 protein expression as well as by promoting lysosomal degradation of CFTR and beta-catenin. Therefore, steviol may represent a promising compound for treatment of polycystic kidney disease. (C) 2017 Elsevier Masson SAS. All rights reserved.

Purpose: Autophagy plays a critical role in PCa development. DAXX has a potent pro-survival effect by enhancing cell growth in PCa via suppression of autophagy. Here, we depicted a network governed by DAXX and SPOP by which the autophagy pathway is suppressed through the ubiquitination and modulation of key cellular signaling pathways mediators including LAMP2 and RARRES1. Materials and Methods: Through network-based bioinformatics approaches, the expression levels of DAXX, RARRES1, LAMP2, and SPOP genes was assessed in 50 PCa tissues and 50 normal adjacent from the same sample as well as 50 benign prostatic hyperplasia (BPH) tissues by quantitative RT-PCR. The normal adjacent tissues were taken from regions more than 5mm away from the bulk of those tumor tissues with clearly distinct margins. RNA extraction, cDNA synthesis and Real-time Quantitative RT-PCR were done for assessment of gene expression. To evaluate the primary gene network centered on autophagy pathway, according to the Query-dependent weighting algorithm, these two networks were integrated with Cytoscape 3.4 software. Results: We found that in PCa tissues the DAXX expression level was significantly increased (P < 0.001) and the expressions of SPOP, RARRES1, and LAMP2 were significantly down-regulated, when compared to both control groups including normal adjacent and BPH tissues. Moreover, significant correlations were observed between expression levels of all four genes. Additionally, ROC curve analysis revealed that LAMP2 had the most sensitivity and specificity. Conclusion: These findings suggest that the contribution of SPOP, DAXX, RARRES1, and LAMP2 together could be a putative regulatory element acting as a prognostic signature and therapeutic target in PCa.