It may take cells in different stages of development to cause breast cancer to progress and spread, according to recent research published in eLife.

The findings demonstrated the importance of accounting for specific cell states present in a tumor in order to determine the appropriate combination of drugs necessary to eliminate all the cell states present and halt treatment resistance, according to the study authors.

The researchers noted that the variation between cell states may cause difficulties during treatment if differences in cell states are not accounted for.

"This diversity poses a problem to treating patients because particular subsets of tumor cells may be drug resistant and eventually lead to disease recurrence," said co-lead author Syn Yeo, PhD, an instructor at the University of Cincinnati, in a press release. "One of the factors contributing to this diversity is the fact that tumor cells can exist in different cellular states, ranging from more stem-like cells that can become other cell types to more differentiated cells that have been coded to serve a purpose, or do a certain 'job' within the system.”

Yeo explained further that cancer cells with stem-like properties can cause drug resistance. For this reason, they are generally seen as being at the top of the tumor hierarchy with more differentiated tumor cells toward the bottom of the hierarchy.

In order to determine the tumor hierarchy structure more specifically, the researchers identified and categorized singular cells in order to understand the purpose of each cell. Yeo noted that an analysis without this specificity would have obstructed cellular details during their assessment.

"We were able to find a complex spectrum of cell states between different tumor types that can range from stem-cells to the 'beginner cells' to more differentiated cells," he said. “Furthermore, depending on the lineage of the tumor, some may show a spectrum of cell states that are higher up in the hierarchy and vice versa.”

Yeo explained that these results help to clarify the direction for further research.

"These findings are important because they show we need to know more about how these specific cell states contribute to tumor growth so we can target them with combination drug therapies, potentially helping more people who may otherwise experience drug resistance," Yeo said.

REFERENCE
Researchers pinpoint hierarchy of breast cancer cells as potential cause for treatment resistance. Cincinnati, OH: University of Cincinnati; August 25, 2020. sciencedaily.com/releases/2020/08/200825110633.htm. Accessed September 4, 2020.