MRNA vaccines are regarded as a highly promising avenue for next‐generation cancer therapy. Nevertheless, the intricacy of production, inherent instability, and low expression persistence of linear mRNA significantly restrict their extensive utilization. Circular RNAs (circRNAs) offer a novel solution to these limitations due to their efficient protein expression ability, which can be rapidly generated in vitro without the need for extra modifications. Here, we present a novel neoantigen vaccine based on circRNA that induces a potent anti‐tumor immune response by expressing hepatocellular carcinoma‐specific tumor neoantigens. By cyclizing linearRNA molecules, we were able to enhance the stability of RNA vaccines and form highly stable circRNA molecules with the capacity for sustained protein expression. We confirmed that neoantigen‐encoded circRNA can promote dendritic cell (DC) activation and enhance DC‐induced T‐cell activation in vitro, thereby enhancing T‐cell killing of tumor cells. Encapsulating neoantigen‐encoded circRNA within lipid nanoparticles for in vivo expression has enabled the creation of a novel circRNA vaccine platform. This platform demonstrates superior tumor treatment and prevention in various murine tumor models, eliciting a robust T‐cell immune response. Our circRNA neoantigen vaccine offers new options and application prospects for neoantigen immunotherapy in solid tumors.

Dual and multi-stimuli responsive polymeric nanoparticles that respond to two or more signals can further improve drug release performance compared with nanoparticles that respond to a single stimulus. However, usage of such nanoparticles to deliver siRNA and chemotherapeutic drugs in a sequential manner are currently very rare; meanwhile, this technology is vital to optimize the efficacy of chemotherapy towards cancer cells with multidrug resistance. By loading o-nitrobenzyl ester derivative caged DOX (DOC) into the inner poly(lactic-co-glycolic acid) (PLGA) core and adsorbing siRNA of P-gp protein onto the cationic polymeric shell derived from a disulfide-containing alkyl modified polyethylenimine (C₁₆-S-S-PEI), here, a reduction/photo dual responsive device (RPDRD) is successfully designed for programmed P-gp siRNA and doxorubicin delivery. The dual-stimuli design of the RPDRD allows tumor microenvironment-specific and rapid release of P-gp siRNA triggered by the enrichment of reducing agent glutathione (GSH, up to 10 mM) for reversal of drug resistance by initially suppressing P-gp protein expression in MCF/ADR cells and then selectively triggering drug release by external light for chemotherapy afterwards. The sequential release behavior of P-gp siRNA and DOX can be demonstrated both in vitro and in vivo, thus enhancing the intracellular drug retention and optimizing the chemotherapy efficacy of DOX by silencing P-gp; this strategy may have extensive application prospects in MDR cancer treatment in future.

Purpose: The aim of this work was to investigate the clinicopathological significance of fibrinogen gamma chain (FGG) and its biological roles during hepatocellular carcinoma (HCC) development and progression. Methods: The expression of FGG was examined by Western blot and reverse transcription quantitative PCR in two different sample sets, including 24 or 35 pairs of HCC tumor tissues and their corresponding adjacent non-tumorous tissues. Afterward, association analysis between the expression of FGG and clinicopathological characteristics was systematically analyzed in 79 HCC patients. Subsequently, the mobility and invasiveness of SK-HEP-1 cells with FGG overexpression or knockdown were evaluated by transwell assay and wound healing assay. Additionally, the expressions of epithelial to mesenchymal transition (EMT)-associated markers were also detected in FGG overexpressed or silenced SK-HEP-1 cells. Results: The expression of FGG was significantly increased in primary HCC tissues comparing with its corresponding adjacent non-tumorous tissues. Clinical pathological analysis demonstrated that upregulation of intracellular FGG was significantly associated with increased vascular invasion, more satellite nodules, and more advanced TNM stage, and HCC patients with stronger expression of FGG had a higher recurrence rate and correspondingly a shorter overall survival time. Meanwhile, the high expression of FGG was also proved to be an independent risk factor for disease-free survival after surgical resection. In vitro phenotype studies showed that overexpression of FGG could promote the migration and invasion in SK-HEP-1 cells; conversely, these phenotypes could be significantly inhibited by knocking down the expression of FGG. Mechanism studies indicated that FGG could promote the migration and invasion through EMT signaling pathway by regulating the expressions of Slug and ZEB1. Conclusion: FGG played important roles in enhancing cancer cell motility and invasiveness through EMT signaling, and might serve as a potential prognostic biomarker for HCC patients.

It is well known that the stability of RNA, the interaction between RNA and protein, and the correct translation of protein are significant forces that drive the transition from normal cell to malignant tumor. Adenosine deaminase acting on RNA 1 (ADAR1) is an RNA editing enzyme that catalyzes the deamination of adenosine to inosine (A-to-I), which is one dynamic modification that in a combinatorial manner can give rise to a very diverse transcriptome. ADAR1-mediated RNA editing is essential for survival in mammals and its dysregulation results in aberrant editing of its substrates that may affect the phenotypic changes in cancer. This overediting phenomenon occurs in many cancers, such as liver, lung, breast, and esophageal cancers, and promotes tumor progression in most cases. In addition to its editing role, ADAR1 can also play an editing-independent role, although current research on this mechanism is relatively shallowly explored in tumors. In this review, we summarize the nature of ADAR1, mechanisms of ADAR1 editing-dependent and editing-independent and implications for tumorigenesis and prognosis, and pay special attention to effects of ADAR1 on cancers by regulating non-coding RNA formation and function.