Sasa quelpaertensis leaf extract inhibits colon cancer by suppressing colon cancer stemness in vitro and in vivo

Abstract

Colon cancer is a leading cause of cancer death in worldwide. Most colon cancer patients develop recurrence suggesting that colon cancer is driven by a subpopulation of self‐renewing cancer cells, termed cancer stem cell (CSCs), which may be responsible for tumor relapse and resistance against chemotherapy. Targeting CSCs to treat colon cancer may be an important therapeutic strategy. Sasa quelpaertensis Nakai is a bamboo grass that only grows in Jeju Island in South Korea. Although the anti‐obesity and anti‐inflammatory effects of Sasa leaves have been reported, the anti‐cancer stem cell effects of Sasa leaves remain unknown. The aim of this study was to investigate the effects of Sasa quelpaertensis leaves extracts (SQE) on suppressing cancer stemness of colon cancer cell. To obtain CSCs, we isolated CD133+/CD44+ population of HT29 colon cancer cells using Flow Cytometry Cell Sorting (FACS). We found that SQE significantly suppressed CD133+ and CD44+ population using FACS analysis. SQE inhibited colony formation and nonadherent sphere formation which are characteristics of cancer stem cells. SQE down‐regulated expressions of CSC markers, including SOX‐2, Notch1, DLK1, and b‐catenin. Furthermore, SQE down‐regulated the expression of HIF‐1α, and its down‐stream gene, VEGF. In conclusion, SQE has an important role in regulating colon cancer stemness by suppressing self‐renewal potential and CSC markers, thereby contributes to the overall inhibition of cancer cell growth.