New technology from ApoCell, Inc. that can detect liver cancer cells circulating in a patient’s bloodstream may remove the need for potentially dangerous liver biopsies, be used as a screening tool and, ultimately, speed up drug development, according to a pilot study presented this week by Virginia Commonwealth University (VCU) Massey Cancer Centerresearcher Andrew Poklepovic, M.D., at the AACR Annual Meeting 2012 in Chicago, IL.
Poklepovic, an oncologist at VCU Massey in the Division of Hematology, Oncology and Palliative Care and an assistant professor of internal medicine at VCU School of Medicine , examined ApoCell’s ApoStream™ dielectrophoretic cell separation system in 10 patients with advanced hepatocellular carcinoma (HCC), or liver cancer. The study’s results showed that the device could effectively collect circulating tumor cells (CTC) from patients while preserving the cells for analysis outside of the body.
“This is the first time circulating liver cancer cells have been collected without relying on magnetic beads to attach to a protein on the cell’s surface,” says Dr. Poklepovic. “While we tested the device in liver cancer, theoretically it could work in a number of different cancers.”
ApoCell’s capture technique relies on differences in electrical charges between cancer cells and normal blood cells. Due to the difference in charges, cancer cells are attracted to an electrical frequency emanating from a plate in the device whereas blood cells are repulsed. Alternative capture techniques rely on antibodies attached to magnetic beads that bind to epithelial cellular adhesion molecules (EpCAM) on the cancer cells. These alternatives are limited to collecting cancer cells that express significant amounts of EpCAM, which is expressed in less than a third of all HCC tumors. Additionally, the tumor cells are fixed in the alternatives’ capture process and cannot be manipulated after they are collected.
In Poklepovic’s study, different types of liver cancer cells were collected from the same patient, suggesting differences within the tumor cells that were previously unknown. The device may have also captured cells that have undergone epithelial-mesenchymal transformation (EMT), which is a process thought to be induced by chemotherapy and radiotherapy that increases the cells’ resistance to these treatments.
“By analyzing the collected cells, we can monitor the patient’s response to treatment, view genetic changes within the cancer and obtain new insight into the diagnosis and evaluation of each patient’s unique disease,” says Poklepovic. “This technology opens the door to a deeper understanding of the mechanisms of liver cancer.”
Liver cancer is the third leading cause of cancer death in the world, and there is currently only one FDA approved drug – sorafenib – that has been shown to extend survival. Reliable CTC capture techniques could provide a non-invasive way to harvest liver cancer cells, potentially speeding up the development of new drugs.
VCU Massey Cancer Center is already using this technology to evaluate liver cancer cells’ response to a new treatment, combining sorafenib with another anti-cancer drug, vorinostat. There are also studies underway in prostate cancer.
Moving forward, Poklepovic plans to test the ApoCell device on additional samples and utilize genetic analyses to better understand the different types of cancer cells collected using this technique.