Scientists Develop 3-D Human Models for Cancer Research
Scientists have developed a new tumor test system, which they said will allow them to grow, observe and better understand how to treat biopsied human cancer cells.
The findings, published by the Journal of Visualized Experiments (JoVE), will likely alleviate the shortfalls of typical testing methods, researchers said. They noted that they chose to publish in JoVE because it allowed them to best explain and visualize their findings through video.
In previous studies, a common procedure included examining cancer cells in two-dimensional (2-D) glass or plastic structures.
In the new study, scientists from the University Hospital Würzburg found that the benefit of studying tumors in 3-D systems, rather than 2-D systems, was that the cancer cells more closely resemble those living in a human. In a 3-D test system, cells can self-organize, which allows researchers to study tissue organization and cell differentiation. This test system is significant because it paves the way for more suitable research into human disease.
“The ability to model cancer tumors in a more natural 3-D environment will enable the discovery, testing, and validation of future pharmaceuticals in a human-like model,” researchers said.
Cancer remains the second leading cause of death in the United States and accounts for approximately one in every four deaths, according to the American Cancer Society, and millions of dollars in funding goes towards cancer research every year. Research on anti-cancer drug testing, published in 2010 in Oncology Issues, said that in addition to evidence that cancer cells in a 3-D environment respond to drug treatment more like cancer cells do in humans, there are also practical reasons for using 3-D test systems. According to researchers, “Many types of cancer…adhere very poorly to 2-D plastic cell culture surfaces” and that “washing steps cause the cells to detach from the surface and be lost.”
Professor Shuichi Takayama at the University of Michigan has conducted research in combining cancer therapies within a 3-D environment. His findings, published in 2011 in Analyst, showed that researchers can use 3-D testing systems to more efficiently screen out drugs that do not work.
A secondary implication of the new study’s findings is that if scientists can create accurate models of human cancer cells, then they could be able to reduce the need for animal testing.
Takayama said, “Different types of cells can be used to create accurate models of different human diseases, so this can replace the need for animals in some stages of drug development.”
According to Takayama, an overwhelming majority – approximately 90 percent – of cancer deaths is the result of a process called metastasis, against which there is a lack of effective therapies. The reason for this, at least in part, is because of insufficient animals on which to perform tests. Takayama said that reducing or replacing animal studies is important for enhancing the drug development process, as well as from an animal welfare perspective.
It is indisputable that animal testing is an effective method for cancer research, but an ethical debate surrounds it. Scientific evidence shows that animal-based research (including research of cancer, HIV/AIDS, heart disease/stroke, diabetes, Parkinson’s disease, Hepatitis C, birth defects, epilepsy and cystic fibrosis) has contributed to significant medical improvements and innovations, according to findings published in the journal Nature and to the National Institutes of Health (NIH) . However, the new study provides hope that the new testing system will effectively replace a large number of animals used in cancer research.
While scientists are increasingly using cancer research methods similar to the one in the new study, such test systems are a relatively new, and it could be a while before they result in the development of more effective cancer treatments. Researchers who conducted the new study said their successful cancer testing system is a “very important step towards personalized medicine.”
Some scientists also warn about the limitations of 3-D cancer testing systems. One study, published in the Journal of Cell Communication and Signaling, found that although 3-D systems provide benefits that 2-D systems do not, limitations still need to be addressed. Many 3-D models are “still simplistic” and “do not include all the cell types and…components which would truly represent the desired tumor microenvironment,” researchers said.
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