Background/Aims: Endoscopic mucosal resection (EMR) is the primary treatment for duodenal adenomas; however, it is associated with a high risk of perforation and bleeding, especially with larger lesions. The goal of this study was to demonstrate the feasibility and safety of endoscopic suturing (ES) for the closure of mucosal defects after duodenal EMR. Methods: Consecutive adult patients who underwent ES of large mucosal defects after EMR of large (>2 cm) duodenal adenomas were retrospectively enrolled. The OverStitch ES system was employed for closing mucosal defects after EMR. Clinical outcomes and complications, including delayed bleeding and perforation, were documented. Results: During the study period, ES of mucosal defects was performed in seven patients in eight sessions (six for prophylaxis and two for the treatment of perforation). All ES sessions were technically successful. No early or delayed post-EMR bleeding was recorded. In addition, no clinically obvious duodenal stricture or recurrence was encountered on endoscopic follow-up evaluation, and no patients required subsequent surgical intervention. Conclusions ES for the prevention and treatment of duodenal perforation after EMR is technically feasible, safe, and effective. ES should be considered an option for preventing or treating perforations associated with EMR of large duodenal adenomas.

Extracellular vesicles (EVs) function as potent mediators of intercellular communication for many in vivo processes, contributing to both health and disease related conditions. Given their biological origins and diverse functionality from correspondingly unique “cargo” compositions, both endogenous and modified EVs are garnering attention as promising therapeutic modalities and vehicles for targeted therapeutic delivery applications. Their diversity in composition, however, has revealed a significant need for more comprehensive analytical-based characterization methods, and manufacturing processes that are consistent and scalable. In this review, we explore the dynamic landscape of EV research and development efforts, ranging from novel isolation approaches, to their analytical assessment through novel characterization techniques, and to their production by industrial-scale manufacturing process considerations. Expanding the horizon of these topics to EVs for in-human applications, we underscore the need for stringent development and adherence to Good Manufacturing Practice (GMP) guidelines. Wherein, the intricate interplay of raw materials, production in bioreactors, and isolation practices, along with analytical assessments compliant with the Minimal Information for Studies of Extracellular Vesicles (MISEV) guidelines, in conjunction with reference standard materials, collectively pave the way for standardized and consistent GMP production processes.

PURPOSE: Tumor xenograft model is an indispensable animal cancer model. In esophageal squamous cell carcinoma (ESCC) research, orthotopic tumor xenograft model establishes tumor xenograft in the animal esophagus, which allows the study of tumorigenesis in its native microenvironment. MATERIALS AND METHODS: In this study,we described two simple and reproducible methods to develop tumor xenograft at the cervical or the abdominal esophagus in nude mice by direct injection of ESCC cells in the esophageal wall. RESULTS: In comparing these two methods, the cervical one presented with more clinically relevant features, i.e., esophageal stricture, body weight loss and poor survival. In addition, the derived tumor xenografts accompanied a rapid growth rate and a high tendency to invade into the surrounding structures. This model was subsequently used to study the anti-tumor effect of curcumin, which is known for its potential therapeutic effects in various diseases including cancers, and its analogue SSC-5. SSC-5 was selected among the eight newly synthesized curcumin analogues based on its superior anti-tumor effect demonstrated in an MTT cell proliferation assay and its effects on apoptosis induction and cell cycle arrest in cultured ESCC cells. Treatment of orthotopic tumor-bearing mice with SSC-5 resulted in an inhibition in tumor growth and invasion. CONCLUSION: Taken together, we have established a clinically relevant orthotopic tumor xenograft model that can serve as a preclinical tool for screening new anti-tumor compounds, e.g., SSC-5, in ESCC.
Animals ; Apoptosis ; Body Weight ; Carcinogenesis ; Carcinoma, Squamous Cell* ; Cell Cycle Checkpoints ; Cell Proliferation ; Curcumin* ; Epithelial Cells* ; Esophageal Stenosis ; Esophagus ; Heterografts* ; Mass Screening ; Mice ; Mice, Nude ; Therapeutic Uses