PROVIDENCE, RI [Brown University] — In cancer research, it all comes down to a single cell.
Over the last decade, cancer researchers have homed in on the fact that an individual cell from a tumor can be used to perform molecular analyzes that reveal important clues about how the cancer developed, how it spreads and how it may be targeted.
With this in mind, a team of researchers at Brown University has developed an advanced way to isolate single cells from complex tissues. In a study published in Scientific Reports, they show how the approach not only results in high-quality, intact single cells, but is also superior to standard isolation methods in terms of labor, cost and efficiency.
The challenge was to develop a technology to enable researchers to more quickly and easily isolate cells from biopsied cancer tissue to ready it for analysis, said Anubhav Tripathi, study author and director of biomedical engineering at Brown.
“From a technology standpoint, there’s nothing like this available on the market right now,” Tripathi said. “This technology will be useful for those looking for answers using genomics, proteomics, transcriptomics — it will not only make those diagnostic and therapeutic investigations easier, but will also save researchers time and effort.”
Tripathi added that beyond clinical applications, the technology will be useful in biomedical applications like tissue engineering and cell culture.
In single-cell analysis, advanced sequencing techniques are used to obtain genetic profiles of individual cells. This is particularly applicable to cancer tissues, where rare mutations can drive metastasis and treatment response outcomes. A major limitation of the clinical translation of single-cell analysis is the difficulty of isolating single cells from complex tissues, said co-author Nikos Tapinos, an associate professor of neurosurgery and neuroscience at Brown.
Tapinos described a typical workflow using the example of a brain tumor: A piece of the tumor would be removed in an operating room and brought to a lab. There, researchers would use a process involving enzymes to extract nucleic acids from bulk tissue samples and would then perform genetic sequencing en masse.
This process results in low-resolution, potentially inaccurate genetic readouts and poor detection of rare cell types, Tapinos said. The consequences of the loss of this information can be profound, he noted, including the possibility of patient misdiagnosis, creating a substantial lag between the time when the tumor is removed from the patient and the cells are ready for RNA sequencing.
“There is a tremendous need for a technology that allows for the removal of tissue from the patient and, within minutes, results in viable, healthy single cells from which RNA can be isolated,” Tapinos said. “That is exactly what this new process does.”
The advantages of electricity over enzymes
In the new process, a tissue biopsy is placed in a liquid-filled receptacle between two parallel plate electrodes. Instead of enzymes, electric field fluctuations are applied to create opposing forces within the liquid. These forces cause the tissue cells to move in one direction and then in the opposite direction, which leads them to cleanly separate, or disassociate from one another.