Transfection with Plasmid-Encoding lncRNA-SLERCC nanoparticle-mediated delivery suppressed tumor progression in renal cell carcinoma

Background The accumulating evidence confirms that long non-coding RNAs (lncRNAs) play a critical regulatory role in the progression of renal cell carcinoma (RCC). But, the application of lncRNAs in gene therapy remains scarce. Here, we investigated the efficacy of a delivery system by introducing the plasmid-encoding tumor suppressor lncRNA-SLERCC (SLERCC) in RCC cells. Methods We performed lncRNAs expression profiling in paired cancer and normal tissues through microarray and validated in our clinical data and TCGA dataset. The Plasmid-SLERCC@PDA@MUC12 nanoparticles (PSPM-NPs) were tested in vivo and in vitro, including cellular uptake, entry, CCK-8 assay, tumor growth inhibition, histological assessment, and safety evaluations. Furthermore, experiments with nude mice xenografts model were performed to evaluate the therapeutic effect of PSPM-NPs nanotherapeutic system specific to the SLERCC. Results We found that the expression of SLERCC was downregulated in RCC tissues, and exogenous upregulation of SLERCC could suppress metastasis of RCC cells. Furthermore, high expression DNMT3A was recruited at the SLERCC promoter, which induced aberrant hypermethylation, eventually leading to downregulation of SLERCC expression in RCC. Mechanistically, SLERCC could directly bind to UPF1 and exert tumor-suppressive effects through the Wnt/[beta]-catenin signaling pathway, thereby inhibiting progression and metastasis in RCC. Subsequently, the PSPM-NPs nanotherapeutic system can effectively inhibit the growth of RCC metastases in vivo. Conclusions Our findings suggested that SLERCC is a promising therapeutic target and that plasmid-encapsulated nanomaterials targeting transmembrane metastasis markers may open a new avenue for the treatment in RCC. Keywords: lncRNA-SLERCC, Nanoparticles, Renal cell carcinoma, Gene therapy, Tumor suppressor