Despite advances in cancer treatments, cancer is still ranked the second leading cause of death. Cancers are started by cancer stem cells (CSCs). CSCs, also called tumor-initiating cells, are found in tumors and are responsible for the growth of tumors and the spread of cancer to other parts of the body. CSCs are very resistant, and cannot be killed by chemotherapy or radiation treatments. These cells can come from healthy stem cells. The environment surrounding the healthy stem cells and mature cells can cause mutations in the cell’s genetics, resulting in development of CSCs. The environment can also increase tumor resistance to drugs. During preliminary experiments in our laboratory, we have found how the culture environment leads to mutation of human brain cancer cells. The cancer cells were also found to be drug-resistant and have the ability to change shape to resemble colonies of other stem cells. In this project, we hypothesized that stressful conditions cause normal cells to change into CSCs capable of travelling throughout the body. To test the hypothesis, we attempted to examine which environmental changes cause conversion of cancer cells to CSCs. A U87 cell line was cultured in a MEM-FBS solution and concentrations of the antibiotic G418 were administered. The response of the cells to the G418 dosages was quantified by recording the cell confluency over several days. Changes in cell morphology were also recorded. This work did not result in any CSC-like cells. Cells not treated with G418 proliferated to 100% confluency, but all dosages of G418 resulted in at most 8% cell confluency. Cell clusters formed in some of the wells of the cell plates. Future work should use different antibiotic concentrations to find where the cell confluency eventually remains constant
