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Background/Aim: Human dermal fibroblasts (HDFs) are widely used as a skin model in cosmetic and pharmaceutical industry due their advantages for the cosmetic industry and medical aspects. Telomeres are key players in controlling cellular aging, in which telomeres and the telomerase enzyme (hTERT) can maintain proliferative capacity and prolong cellular senescence. The primary aim of the study was to elucidate the underlying mechanisms of hTERT/SV40 immortalization of human dermal fibroblasts. Materials and Methods: Transgenic expression of hTERT and SV40 large antigen, as well as co-transfection of both factors was performed and their significance evaluated in terms of HDF immortalization efficiency. Results: The results showed that the immortalized fibroblasts of all conditions can be cultured in over 60 passages and maintain their telomere length. Further, key markers of skin cells, such as COL1A1, KRT18 and ELASTIN, were up-regulated in immortalized cells. In addition, p53 expression was enhanced in all immortalized cells, in accordance with activation of the SIRT1 gene upon transgenic immortalization. The significant role of SIRT1 in fibroblast proliferation was assessed by shRNA-knockdown, and it was found that SIRT1 silencing led to loss of Ki67, a proliferation marker. Moreover, miR-93, a SIRT1-targeted miRNA, also had a significantly reduced expression in the co-transfected immortalized cells, highlighting the linkage of the miRNA and SIRT1 pathway in the immortalization of human dermal fibroblasts. Conclusion: This evidence from this study could benefit the efficient development of human skin cell lines for use in the cosmetic industry in the future. [ABSTRACT FROM AUTHOR]

Background/aim: Among various types of brain tumors, glioblastoma is the most malignant and highly aggressive brain tumor that possesses a high resistance against anticancer drugs. To understand the underlined mechanisms of tumor drug resistance, a new and more effective research approach is required. The three dimensional (3D) in vitro cell culture models could be a potential approach to study cancer features and biology, as well as screen for anti-cancer agents due to the close mimicry of the 3D tumor microenvironments., Materials and Methods: With our developed 3D alginate scaffolds, Ilumina RNA-sequencing was used to transcriptomically analyze and compare the gene expression profiles between glioblastoma cells in traditional 2-dimensional (2D) monolayer and in 3D Ca-alginate scaffolds at day 14. To verify the reliability and accuracy of Illumina RNA-Sequencing data, ATP-binding cassette transporter genes were chosen for quantitative real-time polymerase chain reaction) verification., Results: The results showed that 7,411 and 3,915 genes of the 3D glioblastoma were up-regulated and down-regulated, respectively, compared with the 2D-cultured glioblastoma. Furthermore, the Kyoto Encyclopaedia of Genes and Genomes pathway analysis revealed that genes related to the cell cycle and DNA replication were enriched in the group of down-regulated gene. On the other hand, the genes involved in mitogen-activated protein kinase signaling, autophagy, drug metabolism through cytochrome P450, and ATP-binding cassette transporter were found in the up-regulated gene collection., Conclusion: 3D glioblastoma tumoroids might potentially serve as a powerful platform for exploring glioblastoma biology. They can also be valuable in anti-glioblastoma drug screening, as well as the identification of novel molecular targets in clinical treatment of human glioblastoma., (Copyright© 2020, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.)