Background: Despite multimodality therapies, the prognosis of patients with malignant brain tumors remains extremely poor. One of the major obstacles that hinders development of effective therapies is the limited availability of clinically relevant and biologically accurate (CRBA) mouse models. Methods: We have developed a freehand surgical technique that allows for rapid and safe injection of fresh human brain tumor specimens directly into the matching locations (cerebrum, cerebellum, or brainstem) in the brains of SCID mice. Results: Using this technique, we successfully developed 188 PDOX models from 408 brain tumor patient samples (both high-and low-grade) with a success rate of 72.3% in high-grade glioma, 64.2% in medulloblastoma, 50% in ATRT, 33.8% in ependymoma, and 11.6% in low-grade gliomas. Detailed characterization confirmed their replication of the histopathological and genetic abnormalities of the original patient tumors. Conclusions: The protocol is easy to follow, without a sterotactic frame, in order to generate large cohorts of tumor-bearing mice to meet the needs of biological studies and preclinical drug testing.

The molecular alterations that initiate the development of multiple myeloma (MM) are not fully understood. Our results revealed that TJP1 was downregulated in MM and positively related to the overall survival of MM patients in The Cancer Genome Atlas (TCGA) database and patient samples. In parallel, cell adhesion capacity representing MM metastasis was decreased in MM patients compared with healthy samples, together with the significantly activated epithelial-to-mesenchymal transition (EMT) transcriptional-like patterns of MM cells. Further analyses demonstrated that TJP1 negatively regulated EMT and consequently positively regulated cell adhesion in MM from TCGA database and MM1s cells. Furthermore, the methylation level of each CpG site on the TJP1 promoter was negatively correlated with TJP1 expression levels. Quantitative real-time PCR and western blot assays demonstrated that methylase DNMT1 regulated the methylation of TJP1. Finally, treatment with a combination of the MM clinical medicine bortezomib, methylation inhibitor, or TJP1 overexpression significantly suppressed the viability and progression of tumor cells of MM orthotopic models. In summary, our results indicate that DNMT1 promotes the methylation of TJP1 promoter, thereby decreasing its expression and regulating the development of EMT-inhibited MM cell adhesion. Therefore, methylation of TJP1 is a potential therapeutic agent to prevent the progression of MM disease.

Background/Objectives: The AXL receptor tyrosine kinase is a promising therapeutic target in solid tumors, yet conventional viral vector-engineered CAR-T cells face critical limitations, including risks of insertional mutagenesis and immunogenicity from murine-derived single-chain variable fragments (scFvs). This study aimed to develop and evaluate mRNA-engineered fully human AXL CAR-T (^mfhAXL CAR-T) cells as a safer, scalable alternative for solid tumor immunotherapy. Methods:^mfhAXL CAR-T cells were generated via electroporation-mediated delivery of in vitro transcribed mRNA encoding a fully human AXL-specific CAR. CAR expression kinetics and T-cell viability were quantified by flow cytometry. Antitumor activity was assessed through in vitro co-cultures with AXL-positive lung and pancreatic cancer cells, measuring cytotoxicity, cytokine secretion, and specificity. In vivo efficacy was evaluated in a lung cancer xenograft mouse model, with tumor volume and body weight monitored over 14 days. Results: Flow cytometry confirmed transient but high CAR expression (>90% at 24 h) with preserved T-cell viability (>90%). In vitro, ^mfhAXL CAR-T cells exhibited dose-dependent cytotoxicity and antigen-specific cytokine secretion. In vivo, four administrations of ^mfhAXL CAR-T cells suppressed tumor growth without body weight loss. Conclusions: The mRNA-electroporated ^mfhAXL CAR-T platform enables cost-effective, large-scale production, offering a safer alternative to viral vector-based approaches by eliminating risks of insertional mutagenesis and immunogenicity.