Study of the impact of WHSC1 and CEP55 genes silencing in myxofibrosarcoma cells
Details
Download: Mémoire no 5772 Mme Kanagaratnam.pdf (1359.02 [Ko])
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State: Public
Version: After imprimatur
License: Not specified
Serval ID
serval:BIB_A3079407D467
Type
A Master's thesis.
Publication sub-type
Master (thesis) (master)
Collection
Publications
Institution
Title
Study of the impact of WHSC1 and CEP55 genes silencing in myxofibrosarcoma cells
Director(s)
STAMENKOVIC I.
Codirector(s)
MÖLLER E.
Institution details
Université de Lausanne, Faculté de biologie et médecine
Publication state
Accepted
Issued date
2018
Language
english
Number of pages
26
Abstract
Myxofibrosarcoma is one of the most common soft tissue sarcomas, contributing to more than 5% of all adult sarcomas. This neoplasm most often develops in the dermis or subcutaneous tissue of the extremities. However, it may also be deep-seated and arise in other locations such as the head, neck or trunk (1,2). Although adult sarcomas have received more attention in recent years, myxofibrosarcoma remains vastly understudied (about 400 articles referenced on PubMed since the 1950s). Therefore, further knowledge about the tumour-initiating capacity of primary myxofibrosarcoma tumour cells is greatly needed to identify targets that could be susceptible for specific treatments.
By using gene expression microarrays, two genes (WHSC1 and CEP55) were found to be overexpressed in the more aggressive and metastatic primary myxofibrosarcoma cell population “SpA”, as compared to the non-metastatic cell population “DMEM” derived from the same primary myxofibrosarcoma tumour. The present study was aimed at assessing the importance of these two genes for the survival of primary myxofibrosarcoma cells. These genes were silenced using the short hairpin RNA (shRNA) technique in two cell populations, cultured in different conditions (DMEM and SpA). Cell cultures with stable WHSC1 or CEP55 depletion were then injected into the renal capsule of mice to evaluate their tumorigenic capability. Although tumour formation in vivo was decreased to some extent in shRNA-treated cells, as compared to control cells, the tumour-forming ability was not abolished. As it could be partly due to residual protein expression, we designed a complete gene knockout by utilizing another silencing technique, the genome editing CRISPR CAS9 system. To date, these constructs targeting WHSC1 and CEP55, respectively, have not yet been evaluated in the target cells. This study may open the way to a better understanding of the tumorigenesis of myxofibrosarcoma, as well as the role of WHSC1 and CEP55 genes, by studying the impact of their silencing both in vitro and in vivo.
By using gene expression microarrays, two genes (WHSC1 and CEP55) were found to be overexpressed in the more aggressive and metastatic primary myxofibrosarcoma cell population “SpA”, as compared to the non-metastatic cell population “DMEM” derived from the same primary myxofibrosarcoma tumour. The present study was aimed at assessing the importance of these two genes for the survival of primary myxofibrosarcoma cells. These genes were silenced using the short hairpin RNA (shRNA) technique in two cell populations, cultured in different conditions (DMEM and SpA). Cell cultures with stable WHSC1 or CEP55 depletion were then injected into the renal capsule of mice to evaluate their tumorigenic capability. Although tumour formation in vivo was decreased to some extent in shRNA-treated cells, as compared to control cells, the tumour-forming ability was not abolished. As it could be partly due to residual protein expression, we designed a complete gene knockout by utilizing another silencing technique, the genome editing CRISPR CAS9 system. To date, these constructs targeting WHSC1 and CEP55, respectively, have not yet been evaluated in the target cells. This study may open the way to a better understanding of the tumorigenesis of myxofibrosarcoma, as well as the role of WHSC1 and CEP55 genes, by studying the impact of their silencing both in vitro and in vivo.
Keywords
Myxofibrosarcoma, WHSC1, CEP55, shRNA, CRISPR Cas9
Create date
03/09/2019 8:20
Last modification date
08/09/2020 6:10