The Chick Embryo As A Model to Study The Initiation And Growth Of Neuroblastoma

Abstract

Neuroblastoma is pediatric cancer of the sympathetic nervous system which originates from the trunk neural crest cell population during embryonic development. Clinical representation of neuroblastoma ranges from a spontaneous regression to metastatic disease with only about 50% survival rate. Molecular events which turn normal development of sympathetic nervous system to tumorigenic has not been fully elucidated. Improved understanding of mechanisms which lead to neuroblastoma and of mechanisms which cause metastatic neuroblastoma might open new opportunities for better treatment strategies.
In this study we use the chick embryo as a model to establish methods to investigate the initiation and growth of neuroblastoma. To study the initiation of neuroblastoma, the aim was to establish a human-chick chimera model where human pluripotent stem cells would be implanted into the region of trunk neural crest. The method of cell implantation was established and optimized using a conventional neuroblastoma cell line transduced with a GFP (green fluorescent protein) tag. Immunofluorescence analysis of neural tube tissue at trunk neural crest level confirmed that the conditions of established implantation protocol were optimal for cell survival, as our human cells could be detected during migration. Future work of this project includes using trunk neural crest cells generated from human pluripotent stem cells to investigate which genetic abnormalities in these cells lead to neuroblastoma.
Another aim was to establish a chorioallantoic membrane (CAM) assay to study the effect of MOXD1 (DBH-like monooxygenase protein 1) knockout from neuroblastoma cells (SH-EP cell-line) on tumor growth. Tumor xenografts generated with CAM assay were larger in the MOXD1 knockout group. Embryos which were grafted with MOXD1 knockout SH-EP cells had lower survival rates and more tumors in total were formed. This data supplements previous findings of loss of MOXD1 association with aggressiveness of neuroblastoma.

Popular Abstract

Why Do Children Get Cancer? Chick Embryos Will Give Us An Answer!

According to World Health Organization (WHO), approximately 400,000 children worldwide are diagnosed with cancer each year. Cancer can develop anywhere in the body. It starts when alterations in the DNA occur within a healthy cell. DNA is a large and important molecule compactly packed in a nucleus of each cell. DNA can be viewed as an instruction leaflet guiding our cells on how to operate their functions. When serious changes occur to this instruction leaflet, the cell may lose the ability to properly conduct its functions.

During our lifetime our cells divide many times. With each cell division, there is a slight chance that a cell may make a mistake when making a copy of its DNA for a new cell. Therefore, cancer is common among elderly because their cells have multiplied several times. Lifestyle factors like smoking, diet, obesity, and alcohol increase the risk of developing cancer. Therefore, it is odd that some cancers develop in children. Also, cancers commonly found in children are different from those occurring in adults. Adult cancers most commonly develop in organs such as lung, colon, breast, and prostate. Common cancers in children include blood cancer, brain cancer and cancer in the nervous system. In this study, we are trying to understand the origin and biology of neuroblastoma, a childhood tumor that arises in the sympathetic nervous system, responsible for our fight-or-fly response.

What is neuroblastoma?
Around 20 children each year are diagnosed with neuroblastoma in Sweden. This cancer affects mainly children below the age of 5 and is known to arise during the development of the sympathetic nervous system. The mortality rate in so called high-risk neuroblastomas is high (50%). Therefore, an improvement in treatment strategies is needed. Better understanding of how neuroblastoma arises and what biological factors contribute to its severity have a potential to open new opportunities to develop better treatment strategies.

Studying neuroblastoma using chick embryos
Since neuroblastoma starts during the development of an embryo, it is important to have an easily accessible, and suitable model organism of the embryonic development. It might come as a surprise but chick embryos are highly similar to human embryos during their early development. Therefore, it is a good alternative for human embryos. The development of chick embryos takes place in an egg, meaning that while the embryo is developing it can easily be accessed, manipulated, and monitored throughout the development – extremely important for scientific observation!

In our research we use chick embryos to understand on a molecular level, how neuroblastoma starts and what genes make neuroblastoma more severe. We have developed a method where we inject human stem cells which have a potential to become cells of sympathetic nervous system into the chick embryo. We will track these human cells throughout the development and observe how cancer genes behave in these cells. Eventually, we will be able to evaluate what cancer genes and other molecular events are important for the origin of neuroblastoma.

Master’s Degree Project in Molecular Genetics and Biotechnology, 60 credits, 2022 spring
Department of Biology, Lund University
Advisor: Sofie Mohlin, Division of Pediatrics, BMC B11, Lund University

• author: Miltenyte, Enrika
• supervisor: Sofie Mohlin
• organization: Degree Projects in Molecular Biology
• course: MOBN03 20212
• year: 2022
• type: H2 - Master's Degree (Two Years)
• subject: Biology and Life Sciences
• language: English
• id: 9103294
• date added to LUP: 2022-11-17 11:20:48
• date last changed: 2022-11-17 11:20:48