Culture and application of thymic organoids: a review / 生物工程学报

The thymus is a pivotal immune organ of the human body, and it is the place where T cells differentiate and mature. The damage of thymus would easily induce autoimmune diseases and even malignant tumors. For years, researchers have been exploring the process of T cell development and revealing the mechanism of thymic injury and regeneration generally through the monolayer culture system of T cells in vitro. However, the classic monolayer culture system could neither reproduce the unique three-dimensional epithelial reticular structure of the thymus, nor provide the cytokines and growth factors required for the directed differentiation of hematopoietic stem cells into T cells. Thymic organoid technology utilizes cells with stem cell potential to simulate the anatomical structure of the thymus and the signaling pathway mediated by thymic epithelial cells in vitro through three-dimensional culture, which is particularly close to the microenvironment of the thymus in vivo. Thymic organoids show great potential in the study of T cell differentiation and development, thymus-related diseases, reconstruction of immune function, and cell therapy. This paper summarizes the methods for culturing thymic organoids, followed by comparing the advantages and disadvantages of the scaffolds used for culturing. The applications of thymic organoids in the disease model, tumor-targeting therapy, regenerative medicine, and organ transplantation were also discussed, with possible future research directions prospected.

Role of lncRNA PTENP1 in tumorigenesis and progression of bladder cancer and the molecular mechanism / 南方医科大学学报

<p><b>OBJECTIVE</b>To explore the molecular mechanism underlying the biological function of lncRNA PTENP1 in bladder cancer.</p><p><b>METHODS</b>Expressions of PTENP1, PTEN and miR-17 were examined by quantitative reverse transcriptase PCR (qRT-PCR) in 12 bladder cancer tissues. The expression of PTEN was examined by Western blotting in bladder cancer cell lines T24 and 5637 overexpressing PTENP1. Luciferase reporter assay was performed to confirm the targeting of miR-17 to PTENP1 and PTEN. T24 and 5637 cell lines with stable overexpression of PTENP1 and mir-17 were used to investigate effect of PTNE and miR-17 on the function of PTENP1 in bladder cancer.</p><p><b>RESULTS</b>The expression of miR-17 was up-regulated and PTENP1 and PTEN were down-regulated in bladder cancer tissues, where a positive correlation was found between PTENP1 and PTEN expressions and a negative correlation between PTENP1 and miR-17 (P<0.05). Overexpression of PTENP1 in bladder cancer cell lines T24 and 5637 obviously enhanced the expression of PTEN protein. miR-17 was found to target both PTENP1 and PTEN and promote the growth of bladder cancer. miR-17 could partially restore the tumor-suppressing activity of PTENP1 in bladder cancer.</p><p><b>CONCLUSION</b>By binding with miR-17, lncRNA PTENP1 functions as a PTEN competing endogenous RNA (ceRNA) to suppress the progression of bladder cancer.</p>