Exosome‐mediated transfer of RNAs/proteins from mesenchymal stem cells to cancer cells contributes to modulating the cancer stem cell properties

• Main Authors: Ho, Chia-Shin., 賀佳欣
• Other Authors: Lee, Jia-Lin
• Format: Others
• Language: en_US
• Published: 2018
• Online Access: http://ndltd.ncl.edu.tw/handle/se24n4

碩士 === 國立清華大學 === 分子與細胞生物研究所 === 106 === 　　The tumor microenvironment and cancer cells interact with each other in many different ways. Which is including exosomes, a type of extracellular vesicles (EVs), as one of the mediums. Many studies have reported that the specific cargo carried by exosomes has the ability to regulate the characteristics of cancer cells. HuR protein, an RNA-binding protein, can bind to different RNA segments to control the expression of genes, and then change physiological activities of cells. In this study, we mainly would like to study whether the exosomes secreted by mesenchymal stem cells (MSCs) can carry HuR protein/HuR-associated RNAs and affect the properties of cancer cells to make them more similar to cancer stem cells (CSCs). 　　We used the CRISPR/Cas9 technology to knockout ELAVL1 gene (HuR) in lung cancer cells LM-V252 (epithelial-type) and HM20-V252 (mesenchymal-type), and then treated with MSC derived-exosome which containing HuR to observe whether that would affect its functional properties, including testing for the potential to make cancer cells gaining more the CSC properties. First, we found that HuR/HuR-associated RNAs can translocate into MSC-derived exosomes by western blot and immunofluorescence staining, and then most of cancer cells can uptake MSC-derived exosomes after treatment for 24 hours. Furthermore, RT-PCR was used to respectively determine the expression of epithelial-mesenchymal transition (EMT)-related and CSC-related genes. The differences between CRISPR-control V257and ELAVL1 (HuR)-knockout V252 after treatment with MSC derived-exosomes were determined and compared. Interestingly, we found that treatment of MSC-derived exosomes could increase the expression of EMT-related genes in HM20-ELAVL1 (HuR)-knockout cells, whereas the effects were opposite in LM-ELAVL1 (HuR)-knockout cells. In addition, the ability of sphere-forming was increased in HM20-V252 cells after treatment with exosomes but reduced the ability in LM-V252, indicating that the CSC properties of cancer cells could be altered by tumor microenvironment via exosome. 　　Overall, according to these studies, we expect that HuR protein carried by MSC derived-exosomes binds to specific short/long non-coding RNAs and enters into cancer cells to regulate their deterioration degree and promote the CSC properties.