PHILADELPHIA (August 31, 2021)—Researchers at Fox Chase Cancer Center have developed a protocol for procedures to isolate and purify differentiated tumor cells from medulloblastoma in mice and precisely inject these live tumor cells into mouse cerebella.
Medulloblastoma is the most common malignant brain tumor in children and is predominantly located in the cerebellum, said Yijun Yang, PhD, one of the study authors and a postdoctoral associate in the lab of Zeng-jie Yang, MD, PhD, an associate professor in the Cancer Signaling and Epigenetics Program at Fox Chase.
In previous work, Zeng-jie Yang and colleagues discovered that medulloblastoma cells can differentiate in a way that is similar to the normal cells they originated from. Once these cancer cells have differentiated, they tend to be less aggressive than undifferentiated cells and permanently lose their proliferative capacity and tumorigenic potential.
“We found that these differentiated tumor cell express Tag1,” Yijun Yang said. “This is a cell surface protein that is associated with neuronal migration and differentiation.”
Yijun Yang and colleagues are using this cell marker to label those differentiated tumor cells. “We think this strategy could be used to start differentiating medulloblastoma cells from other types of brain tumors and investigate mechanisms underlying medulloblastoma progression,” he said.
To aid in that process, he and his colleagues developed a protocol for the purification of these differentiated tumor cells from medulloblastoma to be transplanted into the cerebellum of mice.
“In our previous work we found that tumors are more than just a cluster of tumor cells, but instead rely on many types of supporting cells that have important functions to facilitate tumor growth,” said Zeng-jie Yang, who was lead author on the study. “This protocol is important because it outlines how to inject medulloblastoma tumor cells precisely into the mouse cerebellum.”
About 30% of human medulloblastoma cases have mutations in the hedgehog pathway. In this protocol, Yijun Yang and colleagues used transgenic mice with conditional deletion of Patched1, which causes medulloblastoma formation in mice with 100% penetrance.
They outlined detailed steps required for isolation of tumor cells from mouse medulloblastomas, purification of differentiated tumor cells by fluorescence-activated cell sorting, and transplantation of tumor cells into cerebella.
Yijun Yang said this strategy could be used for many other types of brain tumors in addition to medulloblastoma. “We may be able to identify other human cell markers on the cell surface and use this strategy to isolate them based on the fact that those cells are differentiated.”
The article, “Purification of Differentiated Tumor Cells From Medulloblastoma for Transplantation Into Mouse Cerebellum,” was published in STAR Protocols.