The copper transporter, SLC31A1, transcriptionally activated by ELF3, imbalances copper homeostasis to exacerbate cisplatin-induced acute kidney injury through mitochondrial dysfunction.

Acute kidney injury (AKI) is a common complication of cisplatin chemotherapy, which greatly limits its clinical effect and application. This study explored the function of solute Carrier Family 31 Member 1 (SLC31A1) in cisplatin-induced AKI and its possible mechanism. Mice and HK-2 cells were exposed to cisplatin to establish the in vivo and in vitro AKI models. Cell viability was detected by CCK-8. Mitochondrial and oxidative damage was determined by Mito-Tracker Green staining, mtROS level, ATP production, mitochondrial membrane potential, MDA content and CAT activity. AKI was evaluated by renal function and histopathological changes. Apoptosis was detected by TUNEL and caspase-3 expression. Molecule expression was measured by RT-qPCR, Western blotting, and immunohistochemistry. Molecular mechanism was studied by luciferase reporter assay and ChIP. SLC31A1 level was predominantly increased by cisplatin exposure in AKI models. Notably, copper ion (Cu+) level was enhanced by cisplatin challenge. Moreover, Cu+ supplementation intensified cisplatin-induced cell death, mitochondrial dysfunction, and oxidative stress in HK-2 cells, indicating the involvement of cuproptosis in cisplatin-induced AKI, whereas these changes were partially counteracted by SLC31A1 knockdown. E74 like ETS transcription factor 3 (ELF3) could directly bind to SLC31A1 promoter and promote its transcription. ELF3 was up-regulated and positively correlated with SLC31A1 expression upon cisplatin-induced AKI. SLC31A1 silencing restored renal function, alleviated mitochondrial dysfunction, and apoptosis in cisplatin-induced AKI mice. ELF3 transcriptionally activated SLC31A1 to trigger cuproptosis that drove cisplatin-induced AKI through mitochondrial dysfunction, indicating that SLC31A1 might be a promising therapeutic target to mitigate AKI during cisplatin chemotherapy.

Ropivacaine suppresses the progression of renal cell carcinoma through regulating the lncRNA RMRP/EZH2/CCDC65 axis.

BACKGROUND: Renal cell carcinoma (RCC) is a common malignancy. Local anesthetics were displayed powerful effects against various cancers. This study aims to probe the functions and molecular mechanism of ropivacaine in RCC. METHODS: Different concentrations of ropivacaine were performed to administrate RCC cells including 786-O and Caki-1 cells. Cell viability and cell apoptosis were examined using CCK-8 and flow cytometry, respectively. Cell migration and invasion were determined by transwell assay. RMRP and CCDC65 expression was firstly predicted using TCGA dataset and further validated in RCC cells using qRT-PCR and western blot. The interactions among RMRP, EZH2 and CCDC65 were verified by RNA immunoprecipitation (RIP) and chromatin immunoprecipitation (ChIP) assays. RESULTS: Ropivacaine effectively suppressed RCC cell viability, migration and invasion and enhanced cell apoptosis rate. Aberrantly elevated RMRP expression in RCC tissues was predicted by TCGA database. Interestingly, overexpressed RMRP observed in RCC cells could be also blocked upon the administration of ropivacaine. Likewise, RMRP knockdown further strengthened ropivacaine-mediated tumor suppressive effects on RCC cells. In terms of mechanism, RMRP directly interacted with EZH2, thereby modulating the histone methylation of CCDC65 to silence its expression. Moreover, ropivacaine inhibited tumor growth in mice bearing RCC tumor through regulating RMRP/EZH2/CCDC65 axis. CONCLUSION: In sum up, our work revealed that ropivacaine suppressed capacities of RCC cell viability, migration and invasion through modulating the RMRP/EZH2/CCDC65 axis, which laid the experimental foundation of ropivacaine for clinical application in the future.