Replication‐competent adenovirus (RCAd) has been used extensively in cancer gene therapy, and tumor‐selection is critical for the use of replication‐competent adenovirus. Here we investigated the anti‐tumor characterization of oncolytic virus, whose E1A gene is under the control of a renal cell carcinoma specific promoter – the G250 promoter. The constructed oncolytic virus G250‐Ki67 is armed with transgene of Ki67‐siRNA, and G250‐ZD55‐Ki67 also with E1B‐55 KD deleted. The tumor‐specific expression of E1A and Ki67 was demonstrated by Western blot and immunohistochemistry staining, and the tumor‐specific cytotoxicity was assessed by crystal violet staining and cell viability assays. The G250‐Ki67 and G250‐ZD55‐Ki67 adenoviruses could express E1A protein in 786‐O and OSRC cell lines but not in ACHN and HK‐2 cell lines. The expression of Ki67 gene in 786‐O and OSRC cell lines were suppressed by these adenoviruses. The cytotoxic effects induced by G250‐ZD55‐Ki67 and G250‐Ki67 were more obvious on the 786‐O cell lines than on the OSRC cell lines. Each group of adenoviruses could inhibit the proliferation of the 786‐O cells and OSRC cells. However, the effects induced by G250‐ZD55‐Ki67 and G250‐Ki67 on 786‐O cells were stronger than on OSRC cells. Moreover, G250‐ZD55‐Ki67 had enhanced antitumor activities in these renal cancer cells compared with G250‐Ki67. G250 promoter‐derived CRAds carrying Ki67‐siRNA could highly amplify and express Ki67‐siRNA in renal cancer cells with expression of G250 antigen, inhibit renal cancer cells proliferation and induce apoptosis. These results demonstrated that the G250‐specific oncolytic adenovirus expressing Ki67‐siRNA is applicable for human renal clear cell cancer therapy.

Background & Aims: Intrahepatic cholangiocarcinoma (iCCA) has two main histological subtypes: large and small duct‐type iCCA, which are characterized by different clinicopathological features. This study was conducted with the purpose of expanding our understanding of their differences in molecular features and immune microenvironment.Methods: We selected 132 patients who underwent radical surgery at our department between 2015 and 2021 for clinical and survival analyses. Whole‐exome sequencing was performed to analyse mutational landscapes. Bulk RNA sequencing and single‐cell RNA sequencing data were used for pathway enrichment and immune infiltration analyses based on differentially expressed genes. The function of PPP1R1B was analysed both in vitro and in vivo and the gene mechanism was further investigated.Results: We found that large duct‐type iCCA had worse overall survival and recurrence‐free survival rates than small duct‐type iCCA. Mutations in ARID1A, DOT1L and ELF3 usually occur in large duct‐type iCCA, whereas mutations in IDH1 and BAP1 occur in small duct‐type iCCA. Among the differentially expressed genes, we found that PPP1R1B was highly expressed in large duct‐type iCCA tumour tissues. Expression of PPP1R1B promoted cell proliferation, migration and invasion and indicated a worse prognosis. A combination of USF2 with the promoter of PPP1R1B can enhance gene expression in iCCA, which may further affect the expression of genes such as AHNAK, C4BPA and activating the PI3K/AKT pathway.Conclusions: Our findings extend our understanding of large and small duct‐type iCCA. In addition, PPP1R1B may serve as a potential marker and therapeutic target for large duct‐type iCCA.

The ubiquitin–proteasome system (UPS) plays a pivotal role in determining protein fate, regulating signal transduction, and maintaining cellular homeostasis. Protein ubiquitination, a key post-translational modification, is orchestrated by the sequential actions of three primary enzymes, ubiquitin-activating enzyme (E1), ubiquitin-conjugating enzyme (E2), and ubiquitin protein ligase (E3), alongside the regulatory influence of deubiquitinases (DUBs) and various cofactors. The process begins with E1, which activates ubiquitin molecules. Subsequently, E2 receives the activated ubiquitin from E1 and transfers it to E3. E3, in turn, recognizes specific target proteins and facilitates the covalent attachment of ubiquitin from E2 to lysine residues on the target protein. Among the E2 enzymes, ubiquitin-conjugating enzyme E2O (UBE2O) stands out as a unique E2–E3 hybrid enzyme. UBE2O directly mediates the ubiquitination of a wide array of substrates, including 5′-AMP-activated protein kinase catalytic subunit alpha-2 (AMPKα2), MAX interactor 1 (Mxi1), and v-maf musculoaponeurotic fibrosarcoma oncogene homolog (c-Maf), among others. In this narrative review, we will explore the structural characteristics of UBE2O and elucidate its molecular functions. Additionally, we will summarize recent advancements in understanding the role of UBE2O in various tumors, Alzheimer’s disease (AD), and metabolic diseases. Finally, we will discuss the potential of targeting UBE2O as a novel therapeutic strategy for the treatment of human diseases.

Cellular immunotherapy has emerged as a transformative approach in oncology, revolutionizing cancer treatment paradigms. Since the groundbreaking development of induced pluripotent stem cells (iPSCs) by Yamanaka in 2008, significant progress has been made in generating various iPSCs-derived immunocytes, including T cells, dendritic cells, macrophages, natural killer (NK) cells, and B cells. These engineered immune cells offer unprecedented opportunities for personalized cancer therapy as they can be derived from patients’ own cells to minimize immune rejection. In addition, various new techniques are being used for the induction and amplification of iPSCs-derived immunocytes, such as small-molecule techniques, 3D culture systems, nanotechnology, and animal models for the in vivo amplification of immunocytes. Of course, challenges remain in improving immunocyte characteristics. Targeting efficiency needs enhancement to better distinguish tumor cells from healthy tissue, while biological activity must be optimized for sustained antitumor effects. Safety concerns, particularly regarding potential off-target effects and cytokine release syndrome, require further investigation. The immunosuppressive nature of tumor microenvironment also poses significant hurdles for solid tumor treatment. Ongoing clinical trials are exploring the therapeutic potential of iPSCs-derived immunocytes, with researchers investigating combination therapies and genetic modifications to overcome current limitations.