Revolutionizing digestive system tumor organoids research: Exploring the potential of tumor organoids.

Digestive system tumors are the leading cause of cancer-related deaths worldwide. Despite ongoing research, our understanding of their mechanisms and treatment remain inadequate. One promising tool for clinical applications is the use of gastrointestinal tract tumor organoids, which serve as an important in vitro model. Tumor organoids exhibit a genotype similar to the patient's tumor and effectively mimic various biological processes, including tissue renewal, stem cell, and ecological niche functions, and tissue response to drugs, mutations, or injury. As such, they are valuable for drug screening, developing novel drugs, assessing patient outcomes, and supporting immunotherapy. In addition, innovative materials and techniques can be used to optimize tumor organoid culture systems. Several applications of digestive system tumor organoids have been described and have shown promising results in related aspects. In this review, we discuss the current progress, limitations, and prospects of this model for digestive system tumors.

3D-bioprinted double-crosslinked angiogenic alginate/chondroitin sulfate patch for diabetic wound healing.

Improving chronic wound healing remains a challenge in the clinical practice. In this study, we developed double-crosslinked angiogenic 3D-bioprinted patches for diabetic wound healing by the photocovalent crosslinking of vascular endothelial growth factor (VEGF) using ultraviolet (UV) irradiation. 3D printing technology can precisely customize the structure and composition of patches to meet different clinical requirements. The biological polysaccharide alginate and chondroitin sulfate methacryloyl were used as biomaterials to construct the biological patch, which could be crosslinked using calcium ion crosslinking and photocrosslinking, thereby improving its mechanical properties. More importantly, acrylylated VEGF could be easily and rapidly photocrosslinked under UV irradiation, which simplified the step of chemically coupling growth factors and prolonged VEGF release time. These characteristics suggest that 3D-bioprinted double-crosslinked angiogenic patches are ideal candidates for diabetic wound healing and other tissue engineering applications.

Fisetin Alleviates Neointimal Hyperplasia via PPARγ/PON2 Antioxidative Pathway in SHR Rat Artery Injury Model.

The phenotypic transformation of proliferation and migration in vascular smooth muscle cells (VSMCs) from media to intima is the basic pathology of neointimal hyperplasia after angioplasty in hypertensive patients. Angiotensin II (AngII) stimulates oxidative stress in VSMC, inducing VSMC proliferation and migration, which is a critical factor in both developments of hypertension and angioplasty-induced arterial restenosis. Fisetin, a plant flavonoid polyphenol, has been reported to be antioxidative and potent senolytic. It is unknown whether fisetin would inhibit neointimal hyperplasia. Therefore, we investigated the role of fisetin in neointimal formation in vitro and in vivo. The rat thoracic aortic smooth muscle cells (A10 cells) stimulated by AngII were used as the in vitro neointimal hyperplasia model, where AngII significantly induced the proliferation and migration in A10 cells. We found that fisetin could dose-dependently inhibit the effect of AngII via inducing the expression of an antioxidant, paraoxonase-2 (PON2), whose overexpression could inhibit the proliferation and migration of A10 cells and downexpression by siRNA had the opposite effect. Furthermore, we found the mechanism of fisetin's inducing PON2 expression involved PPARγ. Rosiglitazone, a PPARγ agonist, could increase PON2 expression in A10 cells, while the PPARγ inhibitor prevented the effect of fisetin on PON2. The in vivo neointimal hyperplasia model was established 2 weeks after the carotid artery balloon injury in SHR rats. Administration of fisetin (ip 3 mg/kg daily for 2 weeks) right after the injury significantly increased PON2 expression in the artery, inhibiting ROS production, and efficiently reduced carotid neointimal hyperplasia. These results indicate that fisetin increases the expression of antioxidant PON2 via activation of PPARγ, reducing oxidative stress, inhibiting VSMC proliferation and migration, and alleviates neointimal hyperplasia after intimal injury. PON2 may be a potential therapeutic target to reduce arterial remodeling after angioplasty in hypertensive patients.

Clear cell carcinoma, not otherwise specified, of salivary glands: a clinicopathologic study of 4 cases and review of the literature.

Clear cell carcinoma, not otherwise specified (CCC-NOS), is a recently described rare malignant salivary neoplasm. We report the clinicopathologic and immunohistochemical features of 4 cases. The results were then analyzed collectively with the approximate 60 cases of CCC-NOS reported in the English-language literature to define the characteristics of this unusual neoplasm. Combining our cases with those in the literature, a total of 66 cases, confirms that CCC-NOS is a low-grade malignant neoplasm with distinctive clinical and pathologic features. It arises primarily in the minor salivary glands (91% of cases), particularly in the palate or base of tongue, and usually occurs in patients >30 years of age (mean 54.2 years) with a female-to-male ratio of 1.4:1; 12.3% of patients experience local recurrences, 19.3% develop positive regional lymph nodes, 8.8% have distant metastases, and 3.5% die of the disease. Immunohistochemical study focusing on tumor differentiation was performed for our cases, and the findings support the concept that CCC-NOS is of ductal epithelial origin without myoepithelial cell participation.

[Expression of nm23 and proliferating cell nuclear antigen (PCNA) in human brain gliomas and their significance].

BACKGROUND & OBJECTIVE: Brain gliomas seldom undergo extracranial metastasis. Local recurrence is the main reason of tumor patient's death. Therefore, it is important to detect tumor biological features through determination of gene expression. This study was designed to investigate the expression of nm23 (non-metastasis gene, nm23)and PCNA (proliferating cell nuclear antigen) and evaluate the malignancy, recurrence, and prognosis of the tumor. METHODS: In 50 specimens of different malignant gliomas,the expression of nm23 and PCNA were examined using SP immunohistochemical staining. RESULTS: (1)The label indexes of nm23 and PCNA in low-grade gliomas were 3.40+/-0.27 and 3.60+/-0.05, respectively; while the label indexes of nm23 and PCNA in high-grade gliomas were 1.72+/-0.18 and 6.20+/-0.23, respectively.There was significant difference between the two groups(P< 0.05). (2)The positive rates of nm23 and PCNA were 56% (14 cases) and 64% (16 cases) in 25 cases of low-grade gliomas, while the positive rates of nm23 and PCNA were 12% (3 cases) and 88% (22 cases) in 25 cases of high-grade gliomas. There was significant difference between the two groups (P< 0.05). (3)The positive rates of nm23 and PCNA were 0% (0 cases) and 100% (9 cases) in 9 cases of recurrent gliomas, while the positive rates of nm23 and PCNA were 50%(34 cases) and 50%(4 cases) in 8 cases of non-recurrent gliomas. There was significant difference between the two groups (P< 0.05). (4)The label indexes of nm23 and PCNA in gliomas were inversely correlated (r=-0.5335,P< 0.001). CONCLUSION: (1)The expression of nm23 is inversely correlated with the malignancy of gliomas,i.e.the lower expression indicates the higher malignancy. (2)The expression of PCNA is associated with the increased malignancy. (3)Both nm23 and PCNA may be useful biological markers to evaluate the malignancy and prognosis of patients with gliomas.