Regulation of Human Colorectal Cancer Cells in Tumor Spheroids by Sodium Butyrate

Butyrate exerts strong anti-colorectal cancer effects via epigenetic regulation. However, whether butyrate has a negative impact on colorectal cancer in vivo remains unclear. Therefore, this study aimed to investigate whether butyric acid can regulate the growth of colorectal cancer cells using spheroids as an in vivo model. A three-dimensional (3D) culture system was used to form spheroids from the human colorectal cancer cell line HT-29. Spheroids formed in the 3D culture system exhibited some malignant cancer phenotypes (increased cancer stem cell marker levels, anticancer drug resistance, and G0/G1 phase accumulation in the cell cycle) compared with cells in the two-dimensional cell culture system. Sodium butyrate (SB) treatment suppressed cancer stem cell marker levels in spheroids and induced differentiation by increasing the alkaline phosphatase activity. Additionally, SB-induced changes in genes related to cell cycle control indicated that SB reactivated the cell cycle in spheroids, regulating the transition from the G0 to G1 phase. Furthermore, SB treatment induced cell death via apoptosis, which might be due to G1 arrest in the cell cycle. In conclusion, SB induced the differentiation and subsequent cell death of HT-29-derived cancer cells in spheroids, highlighting its potential as a novel anticancer agent for colorectal cancer.