New methods for identification and treatment of cancer cells continue to be investigated. Colon cancer, one of the leading causes of cancer death in the United States, has been used in samples to identify and treat in certain studies. Through previous studies, treatments for people with colon cancer have been utilized, but the treatments still present issues associated with the treatment of cancers. The proper identification of cancer cells and the high toxicity associated with some of the treatments are two of those issues. Research into procedures to reduce the identification time of cancer cells and lower the exposure to toxic chemicals in the body, led to scientists modifying the delivery of the identification markers and treatments with nanotechnology.
Nanoparticles are a viable solution to cancer cell identification and drug toxicity issues and its use with identification of cancer cells and treatments was researched. Ultrafine nanoparticles, which are less than 100nm in diameter, have shown a higher effectiveness for diffusing encapsulated treatments. Up to 85% effectiveness has been reported in some cases.1 The small size of nanoparticles also allows the ability to control what interactions take place by what is encapsulated or what is used to encapsulate the particle. The use of nanoparticles to identify and treat cancer cells was reported by two studies published in Nanoletters and Cancer Prevention Research.
Identifying Cancer Cells
The use of nanoparticles as labeling agents in immunoassays (tests that use antibodies to detect specific molecules) offers an improvement in sensitivity over traditional enzyme or dye labeling agents. When combined with specific antibodies, it was reported that nanoparticles can target tumor-expressed proteins with high affinity and specificity.2 This was tested with circulating tumor cells (CTCs) and epithelial cell adhesion molecules (EpCAMs). CTCs are cells that are released from a tumor and are traveling in physiological fluids.2 Their quantification can be used to predict patient prognosis and evaluate the effects of therapeutic treatments. To identify the cells, the knowledge that cancer cells overexpress specific proteins can be used to label the cells. EpCAM is one of those proteins as it has a low expression amount in human epithelial tissues, but ends up overexpressed in solid carcinomas. EpCAM is found in 98% of colorectal adenocarcinomas and is related inversely to the prognosis.
Using specific antibodies labeled with gold nanoparticles (AuNPs) and magnetic beads (MBs) capture platforms in liquid suspensions, the EpCAM protein can be used to label the CTCs. Another protein overexpressed is the carcinoembryonic antigen (CEA) in colon cancer cells and can also be utilized as a marker. The AuNPs are already known for their excellent work in labeling with optical and electrochemical detection of DNA and proteins.3 The human colon cell line (Caco2) was used because of...