No abstract

Calorie restriction (CR) extends lifespan and increases resistance to multiple forms of stress, including renal ischemia-reperfusion (I/R) injury. However, whether CR has protective effects on contrast-induced nephropathy (CIN) remains to be determined. In this study, we evaluated the therapeutic effects of CR on CIN and investigated the potential mechanisms. CIN was induced by the intravenous injection of iodinated contrast medium (CM) iopromide (1.8 g/kg) into Sprague Dawley rats with normal food intake or 40% reduced food intake, 4 weeks prior to iopromide administration. We found that CR was protective of CIN, assessed by renal structure and function. CM increased apoptosis, reactive oxygen species (ROS), and inflammation in the renal outer medulla, which were decreased by CR. The silent information regulator 1 (SIRT1) participated in the protective effect of CR on CIN, by upregulating glutathione peroxidase 4 (GPX4), a regulator of ferroptosis, because this protective effect was reversed by EX527, a specific SIRT1 antagonist. Our study showed that CR protected CIN via SIRT1/GPX4 activation. CR may be used to mitigate CIN.

Hypertensive nephropathy (HN) is a common cause of end-stage renal disease with renal fibrosis; chronic kidney disease is associated with elevated serum gastrin. However, the relationship between gastrin and renal fibrosis in HN is still unknown. We, now, report that mice with angiotensin II (Ang II)-induced HN had increased renal cholecystokinin receptor B (CCKBR) expression. Knockout of CCKBR in mice aggravated, while long-term subcutaneous infusion of gastrin ameliorated the renal injury and interstitial fibrosis in HN and unilateral ureteral obstruction (UUO). The protective effects of gastrin on renal fibrosis can be independent of its regulation of blood pressure, because in UUO, gastrin decreased renal fibrosis without affecting blood pressure. Gastrin treatment decreased Ang II-induced renal tubule cell apoptosis, reversed Ang II-mediated inhibition of macrophage efferocytosis, and reduced renal inflammation. A screening of the regulatory factors of efferocytosis showed involvement of peroxisome proliferator-activated receptor α (PPAR-α). Knockdown of PPAR-α by shRNA blocked the anti-fibrotic effect of gastrin in vitro in mouse renal proximal tubule cells and macrophages. Immunofluorescence microscopy, Western blotting, luciferase reporter, and Cut&tag-qPCR analyses showed that CCKBR may be a transcription factor of PPAR-α, because gastrin treatment induced CCKBR translocation from cytosol to nucleus, binding to the PPAR-α promoter region, and increasing PPAR-α gene transcription. In conclusion, gastrin protects against HN by normalizing blood pressure, decreasing renal tubule cell apoptosis, and increasing macrophage efferocytosis. Gastrin-mediated CCKBR nuclear translocation may make it act as a transcription factor of PPAR-α, which is a novel signaling pathway. Gastrin may be a new potential drug for HN therapy.

Background: Emerging evidence suggests that p53 participates in the regulation of tumor immunity. TP53 activation in the myeloid linage suppresses alternative (M2) macrophage polarization and attenuates tumor development and invasion. Retrospective clinical analyses suggested that MDM2 amplification is associated with hyper-progression. Targeting MDM2-p53 pathway may represent a novel strategy for reversing immunosuppression and enhancing antitumor immunity of PD-1/PD-L1 blockade. APG-115 is a potent and orally active small-molecule MDM2 protein inhibitor. Binding to MDM2 protein, APG-115 restores p53 expression, activates p53 -mediated apoptosis in tumor cells retaining wild-type p53. Preclinical studies demonstrated that APG-115 promoted the production of proinflammatory cytokines in T cells, enhanced CD4 þ T cell activation, and increased PD-L1 expression on tumor cells. Enhanced antitumor activity was demonstrated in syngeneic tumor models after APG-115 combined with PD-1 blockade. Methods: APG-115 has been evaluated as a single agent in a Phase I study in US (NCT02935907). In this study, total six dose levels (10 mg, 20 mg, 50 mg, 100 mg, 200 mg and 300 mg) have been tested. The preliminary results suggested a favorable safety and tolerability profile. APG-115 exhibited an approximately dose proportional increase in exposure in PK analyses. A Phase Ib/II study of APG-115 in combination with pembrolizumab for treatment of patients with metastatic solid tumor is ongoing. Pembrolizumab is administrated as a fixed dose of 200mg IV on d1 of a 21-d cycle. Safety, tolerability, and determination of the MTD and RP2D are primary objectives of phase Ib. Results: The second cohort (APG 115 at 100 mg) has enrolled, no DLT was observed, and evidence of antitumor activity has been observed. Biomarker studies are ongoing to identify potential selection criteria. Updated clinical data will be presented. Conclusions: This represents one of the first clinical trials to evaluate MDM2mediated resistance to immunotherapy. Clinical trial identification: NCT03611868. Legal entity responsible for the study: Ascentage Pharma Group Corp Limited.

Glioma is the most common malignant primary brain tumor with an inferior survival period and unsatisfactory prognoses. Identification of novel biomarkers is important for the improvements of clinical outcomes of glioma patients. In recent years, more and more biomarkers were identified in many types of tumors. However, the sensitive markers for diagnoses and prognoses of patients with glioma remained unknown. In the present research, our team intended to explore the expression and clinical significance of ABCC3 in glioma patients. Sequential data filtration (survival analyses, independent prognosis analyses, ROC curve analyses, and clinical association analyses) was completed, which gave rise to the determination of the relationship between glioma and the ABCC3 gene. Clinical assays on the foundation of CGGA and TCGA datasets unveiled that ABCC3 expression was distinctly upregulated in glioma and predicted a shorter overall survival. In the multivariable Cox analysis, our team discovered that the expression of ABCC3 was an independent prognosis marker for both 5-year OS (HR = 1.118, 95% CI: 1.052–1.188; P < 0.001 ). Moreover, our team also studied the association between ABCC3 expression and clinical features of glioma patients, finding that differential expression of ABCC3 was remarkably related to age, 1p19q codeletion, PRS type, chemo status, grade, IDH mutation state, and histology. Overall, our findings suggested ABCC3 might be a novel prognosis marker in glioma.