Researchers have investigated the use of zebrafish to identify self-renewing tumor stem cells in prostate cancer, and they say the model could be more beneficial for predicting therapy response, compared with traditional experimental models.
Researchers from Rutgers Cancer Institute of New Jersey say that prostate cancers contain self-renewing tumor stem cells called tumor-initiating cells (TICs). These cells can grow and spread at an uncontrollable rate.
Previous studies have shown that TICs are resistant to standard chemotherapy, the researchers say. Therefore, they emphasize the need to create a treatment strategy that targets the way the cells are able to renew.
But to get there, the researchers say there need to be better ways of identifying TICs.
For their study, published in The Prostate, the researchers analyzed prostate cancer samples from patients who were diagnosed with the disease at Rutgers Cancer Institute of New Jersey between 2008 and 2012.
The researchers first identified tumor cells from the prostate cancer samples by using fluorescent markers.
Traditional methods for identifying TICs include dye staining or cell sorting. But the scientists created a new method that involved “enriching” the tumor cells for TICs, by allowing them to bind with collagen – a glue-like protein that is able to hold together skin, connective and prostate tissues.
The TICs were then transplanted into mice and zebrafish embryos in order to determine their growth and spread frequency.
The researchers discovered that a small amount of the cells that demonstrated binding properties could potentially lead to tumor development and spread, and that this detection was better understood using the zebrafish model.
The researchers say this is due to the zebrafish’s “translucent nature,” which means observation can be made without the need for invasive procedures. Furthermore, the zebrafish demonstrate a lack of immune response to tumor cells.
Dr. Hatem E. Sabaawy, a scientist at Rutgers Cancer Institute and study author, explains that these findings are an important step toward targeting TICs in prostate cancer:
“The self-renewing properties found in prostate TICs are regulated through molecular pathways within the cell. By targeting these pathways and using a few cells from each patient, there may be an opportunity to control progression and recurrence in multiple cancers.
The zebrafish model enables researchers to examine this pathway to progression in real time, thus having the potential to serve as a better tool for personalized cancer therapy.”