The past 26 years, the cancer has been the first of ten major causes of the death all the time, and good countermeasure does not treat the cancer yet. Colorectal cancer (CRC) is a common and lethal malignant disease, it’s the second most frequent cause of cancer-related death in the United States and occupy the third place in ten major causes of the death of the cancer in Taiwan. Surgical resection、chemotherapy and radiotherapy is the major treatment modality for CRC, but therapeutical effect and prognosis are not perfect. Therefore, investigate an effective and fewer side effect anticancer druge is the task of top priority. Apoptosis is one of the organism maintains the balanced and will not cause inflammation, it has fewer side effect for humen body. Therefore the most important strategy of chemotherapy is utilize medicine to induce cancer cell apoptosis.
Cantharidin is the extract of the blister beetle, Mylabris, has been demonstrated to possess antitumor、Immune adjustment、antibiotic and antivirus effect. This thesis main research purpose to probe into that cantharidin can inhibit grow and anticancer mechanism for colorectal cell line (COLO 205).
We use the microscope detects the change of cell type and showing that COLO 205 cell line deal with cantharidin, reduce the cell number、shrink and look like has apoptosome. The MTT assay show that COLO 205 cell line deal with cantharidin, cell survival rate show a dose- and time-dependent manner, IC50 is 20.53μM. Cell cycle analyze show cantharidin induced COLO 205 cell line that cell cycle arrest at G2/M phase then induce apoptosis. Western blot and CDK1 activity show cantharidin can reduce cyclin B and CDK1 activity, and can promote chk1 and p21.
The TUNEL、DAPI and annexin-v assay is to display the apoptosis of cantharidin on COLO 205. The MMP and ROS assay show reduce the mitochondria membrane potential and increase reactive oxygen species. Western blot and caspase activity assay demonstrate that cytochrome c、Bax、Bad and Fas are increase, Bcl-2 is decrease,and promote caspase-3、-8 and -9 activity.
Comprehensive the above result, cantharidin can inhibited cell cycle and activity mitochodria/stress pathway、death receptor pathway then induced cell apoptosis.
