Abstract
Purpose: Corosolic acid (CA), also known as 2α-hydroxyursolic acid, is present in numerous plants, and is reported to exhibit anti-cancer and anti-proliferative activities in various cancer cells such as osteosarcoma, hepatocellular carcinoma, lung adenocarcinoma, and colon cancer. However, the anti-cancer activity of CA on human breast cancer cells and the underlying mechanisms remain to be elucidated. The present study aimed to investigate the anticancer effects of CA in the human breast cancer cell line, MDA-MB-231. Methods: Cell viability, reactive oxygen species (ROS) production, apoptosis marker protein expression, migration, invasion rate, and vascular endothelial growth factor (VEGF) levels were assessed by treating MDA-MB-231 cells to increasing concentrations of CA. Results: The results showed that CA significantly inhibited the cell proliferation of MDA-MB-231 cells in a dose-dependent manner. To assess the effect of CA on apoptosis, nuclei of MDA-MB-231 cells were stained with DAPI solution. Chromatin condensation, which indicates apoptosis, was observed to increase dose-dependently. In addition, western-blot analysis revealed elevated levels of the apoptosis marker proteins (Bax and cleaved caspase 3) subsequent to MDA-MB-231 exposure to CA. ROS production was also increased in the CA-induced apoptosis in MDA-MB-231 treated cells. Interestingly, CA exposure resulted in significantly decreased migration and invasion rates in the MDA-MB-231 cells. Data further revealed that exposure to CA markedly decreased the VEGF concentration, thereby contributing to a reduction in angiogenesis. Conclusion: Our results determined that exposure to CA induces anti-proliferation, apoptosis, and ROS production, and suppresses cell migration and invasion rate in MDA-MB-231 cells. Taken together, these results indicate the potential of CA to be applied as an effective chemotherapeutic agent for treating breast cancer.
본 연구는 인간 유래 유방 암세포 MDA-MB-231를 대상으로 CA에 의한 세포사멸, 세포 이동 및 침윤 효과를 조사하였다. 암세포의 증식 억제 효과는 CA 농도 의존적으로 증식률이 감소하는 것을 확인하였다. CA에 의한 apoptosis 양성 세포를 확인하기 위해 DAPI stain를 진행한 결과, CA 농도 의존적으로 죽은 세포를 확인하였다. MDA-MB-231 세포에서 CA에 의한apoptosis marker 단백질 발현 증가와 ROS production증가를 확인할 수 있었다. 또한 CA에 의한 MDA-MB-231의 세포 이동률이 유의적으로 감소하는 것을 확인하였다. 마지막으로 세포의 이동과 전이 능력 또한 CA를 처리한 군에서 통계적으로 감소하는 것을 확인하였다. 본 연구 결과를 통해서 CA의 암세포 증식률 억제, 세포사멸 증가, 그리고 세포 이동 및 전이 억제 효과가 나타나는 것을 확인했으며, 이 결과를 통해서 향후 유방암에 대한 항암제로 개발될 수 있는 가능성을 가지고 있는 것으로 사료된다.