Investigation of the effects of clinically used chemotherapy combinations on HT29 colon cancer cells and cancer stem cells in two and three dimensional culture conditions

Although advances in cancer treatment have increased the life expectancy and quality of life for various malignancies, colorectal cancer continues to be a major health problem today. Cancer stem cells, one of the biggest factors of this problem, play an important role in tumor growth, metastasis and drug resistance. Therefore, developing effective treatment strategies for CSCs is very important to increase the success of cancer treatment. Within the scope of the thesis study, the effects of chemotherapy drug combinations used in the clinic on HT29 colon cancer cells and HT29 CD133+/CD44+ colon cancer stem cells were investigated in two- and three-dimensional culture conditions and examined in detail. The results showed that 5-Fluorouracil, oxaliplatin, irinotecan and their combinations had different effects on colon cancer cells and colon cancer stem cells. It was determined that 2D and 3D culture conditions directly affected the response of the cells to treatment. It was determined that HT29 CD133+/CD44+ colon cancer stem cells had high migration and invasion capacity in 3D culture. These results contribute to the understanding of the behavior of cancer stem cells that develop resistance to chemotherapy in colon cancer and to the development of targeted treatment strategies specific to these cells.