| Objective:Nowadays, the malignant tumor is developing rapidly and becoming a serious threaten to human health. The therapies of malignant tumor is primarily including operative treatment, chemotherapy and radiotherapy. About60%of patients are treated by chemotherapeutic drugs. Paclitaxel is used as the first-line drugs to the ovarian cancer, which efficiency can be about70%-80%. However, the5-year survival of ovarian cancer remains30%-40%. The chemo-resistance is one of the main reason for treatment failure. According to statistics, more than90%of patients with cancer death attributed to the chemo-resistance in different degree.TGFBI (transforming growth factor-β induced gene) is one of extracellular matrix which has been identified to regulate migration and cellular adhesion. The expression level of TGFBI protein is different in the tumors. For example, it is up-regulated in colorectal cancer, esophagus cancer and renal cancer while is down-regulated in non-small cell lung cancer and breast cancer. A study suggested that TGFBI hypermethylation plays a role in paclitaxel chemo-resistance. TGFBI protein can promote the resistance of non-small cell lung cancer to apoptosis when it is undetectable phenotypes, while up-regulating of TGFBI protein can enhance the sensitivity to some kind of chemotherapeutic drugs. So TGFBI protein has a relationship with chemo-resistance.Studies suggest that polyploidization can lead to chemo-resistance. Our early study show that treating the breast cancer cell with spindle poison can get polyploidy cell (MDA-MB-231-T) which can be grow continuously. The polyploidy cell is more resistant to some of chemotherapeutic drugs such as paclitaxel, docetaxel, vincristine, oxaliplatin,5-FU and epirubicin except for VP16than primary cell. The MDA-MB-231-T can be more sensitivity to paclitaxel when is transfected TGFBI. However is there a relationship between the polyploidization, chemo-resistance and TGFBI protein. The answer is unkown.We used the MDA-MB-231as the object. Up-regulating TGFBI protein by transfecting the cell, comparing the growth inhibition rate by MTT experiment and detecting the cell cycle distribution, apoptosis and DNA ploidy analysis by flow cytometry to explore the relationship between polyploidization, chemo-resistance and TGFBI protein in this study.Methods:1. Transfecting TGFBI-containing plasmid and blank gene to MDA-MB-231cell to form two groups.2. Detecting transfection efficiency by Western Blot experiment.3. Detecting the differences of growth inhibition rate by MTT experiment.4. Analyzing the cell cycle distribution and DNA ploidy analysis by flow cytometry through dyeing the cell with PI.5. Analyzing the apoptosis by using Annexin V-FITC/PI instrument. Results:1. TGFBI protein level is higher in the cells over-expressed TGFBI protein which suggest us the transfection is finished.2. The MTT experiment results show us that the growth inhibition rate is higher in TGFBI over-expression cells than the control cells after treating the cells with paclitaxel in different concentration for48hours.3. The stagnation level of G2/M period in cell cycle is higher and the generation of polyploidy is lower in TGFBI over-expression cells.4. The rate of apoptosis is higher in in TGFBI over-expression cells.Conclusions:1. Up-regulating of TGFBI protein can enhance the sensitivity to paclitaxel.2. TGFBI protein can compete chemo-resistance.3. TGFBI proten can restain the polyploidization leading by spindle poison.4. Polyploidization can lead to chemo-resistance. |
PDF Full Text Request