Downregulation of SAV1 plays a role in pathogenesis of high-grade clear cell renal cell carcinoma

<p>Abstract</p> <p>Background</p> <p>Clinical outcome of patients with high-grade ccRCC (clear cell renal cell carcinoma) remains still poor despite recent advances in treatment strategies. Molecular mechanism of pathogenesis in developing high-grade ccRCC must be clarified. In the present study, we found that SAV1 was significantly downregulated with copy number loss in high-grade ccRCCs. Therefore, we investigated the SAV1 function on cell proliferation and apoptosis in vitro. Furthermore, we attempted to clarify the downstream signaling which is regulated by SAV1.</p> <p>Methods</p> <p>We performed array CGH and gene expression analysis of 8 RCC cell lines (786-O, 769-P, KMRC-1, KMRC-2, KMRC-3, KMRC-20, TUHR4TKB, and Caki-2), and expression level of mRNA was confirmed by quantitative RT-PCR (qRT-PCR) analysis. We next re-expressed SAV1 in 786-O cells, and analyzed its colony-forming activity. Then, we transfected siRNAs of SAV1 into the kidney epithelial cell line HK2 and renal proximal tubule epithelial cells (RPTECs), and analyzed their proliferation and apoptosis. Furthermore, the activity of YAP1, which is a downstream molecule of SAV1, was evaluated by western blot analysis, reporter assay and immunohistochemical analysis.</p> <p>Results</p> <p>We found that SAV1, a component of the Hippo pathway, is frequently downregulated in high-grade ccRCC. SAV1 is located on chromosome 14q22.1, where copy number loss had been observed in 7 of 12 high-grade ccRCCs in our previous study, suggesting that gene copy number loss is responsible for the downregulation of SAV1. Colony-forming activity by 786-O cells, which show homozygous loss of SAV1, was significantly reduced when SAV1 was re-introduced exogenously. Knockdown of SAV1 promoted proliferation of HK2 and RPTEC. Although the phosphorylation level of YAP1 was low in 786-O cells, it was elevated in SAV1-transduced 786-O cells. Furthermore, the transcriptional activity of the YAP1 and TEAD3 complex was inhibited in SAV1-transduced 786-O cells. Immunohistochemistry frequently demonstrated nuclear localization of YAP1 in ccRCC cases with SAV1 downregulation, and it was preferentially detected in high-grade ccRCC.</p> <p>Conclusions</p> <p>Taken together, downregulation of SAV1 and the consequent YAP1 activation are involved in the pathogenesis of high-grade ccRCC. It is an attractive hypothesis that Hippo signaling could be candidates for new therapeutic target.</p

Histological classification of Japanese IgA nephropathy with a small number of glomeruli using Bayes’ theorem

Abstract In Japan an original pathological classification of IgA nephropathy was used, while Oxford classification of IgA nephropathy was used globally. The Oxford classification requires ≥ 8 glomeruli while the Japanese classification requires ≥ 10. Ninety-nine patients diagnosed with IgA nephropathy were included. To determine the accuracy of histological staging, we calculated the posterior probability using Bayes' theorem and adopted three model of prior distribution. First, the actual staging distribution was reclassified using the beta distribution (reclassified distribution). Second a model with the same distribution (actual distribution) as the actual staging was used. Third, a model assuming that all cases are equally distributed (equal distribution) was used. The median number of collected glomeruli was 12 (8–19). There were 33 cases (33%) wherein the glomerular count was ≤ 9. When only cases with ≥ 10 glomeruli were included, the median posterior probability was 91% (74–99) (actual distribution, 90% [74–98]; equal distribution, 85% [73–96]). Even among the 33 cases with ≤ 9 glomeruli, there were approximately 7 cases in which the posterior probability was ≥ 90% for each model. Using Bayesian probabilistic analysis, it was possible to evaluate the histologic classification of IgA nephropathy, even when the number of obtained glomeruli was ≤ 9

Randomised clinical trial: Pemafibrate, a novel selective peroxisome proliferator‐activated receptor α modulator (SPPARMα), versus placebo in patients with non‐alcoholic fatty liver disease

BackgroundPemafibrate is a novel, selective peroxisome proliferator-activated receptor α modulator (SPPARMα). In mice, Pemafibrate improved the histological features of non-alcoholic steatohepatitis (NASH). In patients with dyslipidaemia, it improved serum alanine aminotransferase (ALT).AimsTo evaluate the efficacy and safety of Pemafibrate in patients with high-risk, non-alcoholic fatty liver disease (NAFLD).MethodsThis double-blind, placebo-controlled, randomised multicentre, phase 2 trial randomised 118 patients (1:1) to either 0.2&nbsp;mg Pemafibrate or placebo, orally, twice daily for 72&nbsp;weeks. The key inclusion criteria included liver fat content of ≥10% by magnetic resonance imaging-estimated proton density fat fraction (MRI-PDFF); liver stiffness of ≥2.5&nbsp;kPa, by magnetic resonance elastography (MRE); and elevated ALT levels. The primary endpoint was the percentage change in MRI-PDFF from baseline to week 24. The secondary endpoints included MRE-based liver stiffness, ALT, serum liver fibrosis markers and lipid parameters.ResultsThere was no significant difference between the groups in the primary endpoint (-5.3% vs -4.2%; treatment difference -1.0%, P&nbsp;=&nbsp;0.85). However, MRE-based liver stiffness significantly decreased compared to placebo at week 48 (treatment difference -5.7%, P&nbsp;=&nbsp;0.036), and was maintained at week 72 (treatment difference -6.2%, P&nbsp;=&nbsp;0.024), with significant reduction in ALT and LDL-C. Adverse events were comparable between the treatment groups and therapy was well tolerated.ConclusionsPemafibrate did not decrease liver fat content but had significant reduction in MRE-based liver stiffness. Pemafibrate may be a promising therapeutic agent for NAFLD/NASH, and also be a candidate for combination therapy with agents that reduce liver fat content. ClinicalTrials.gov, number: NCT03350165