Effects Of Repeated Treatment By Anticancer Drugs On Chemo Resistance, Cell Proliferation, Metastasis, Apoptosis In Human Lung Cancer Cell Line

Effects of repeated treatment by anticancer drugs on chemo resistance, cell proliferation, metastasis and apoptosis in human lungcancer cell lineObjective: To explore the variation of the proteins correlated with chemo resistance, cell proliferation, metastasis and apoptosis of the human lung cancer cell lines in repeated treatment by anticancer drugs.Methods: The human lung cancer cell lines (LPET-a-1 and SPA-A-1) were repeatedly treated by anticancer drugs-doxorubicin, etoposide, cisplatin and combination of the three drugs with two concentrations. The interval time of each experiment was recorded. MDR1, MRP, LRP, ref-1, NF-KappaB, MDM2, GST, TS, MT, P27, erbB-2, c-myc, MMP-2, P53, Bax and bcl-2 in the human lung cancer cell lines were tested by flow cytometry. The percentage of cells expressing these proteins and the mean quantity of them were acquired by the fluorescence quantity analysis. We could calculate the number of cells expressing each protein, the mean quantity of each protein in each cell and the total one in each test group after each treatment by different drugs with different concentration. The cell cycles of each group were tested by flow cytometry, too. The apoptosis rate of the human lung cancer cell lines in each test group was calculated by using multi-cycle sofeware.Results: 1. All the cells were found to be killed after given the drugs in higher-dose groups, such as IC50, IC40 groups and DDP's IC30, IC20 ones, the combined IC30 one in LTEP-a-2 cell line as well as DDP's IC30 one, combined IC30 one in SPC-A-1 cell line. The groups left in LTEP-a-2 cell line included the ADM's IC20, IC30 ones, DDP's IC5, IC10 ones, VP-16's IC20, IC30 ones and the combined IC10, IC20 ones. The groups left in SPC-A-1 cell line-4-included the ADM's IC20, IC30 ones, DDP's IC10, IC20 ones, VP-16's IC20, IC30ones and the combined IC10, IC20 ones. After the cells were treated by DDP, most cells were arrested in G2 period, and more cells were in this period as more drugs were given. After the cells were treated by combined drugs, they were mussily arrested in different cycles, and the ratio of the cells in every cycle was not the same after the drugs in different concentration were treated.2.The experiment levels of every protein related to chemo resistance in the human lung cancer cell lines decreased along with the cell continue culture. For the LTEP-a-2 cell line, almost every item in high-dose groups was downregulated after continue treatment, but there was not a rule of the item's variation in low-dose groups and the expression of some proteins after the third treatment was higher than that after the second treatment in one to three groups. Perticularly, the expression of MDR1 in high-dose groups was lower than that of control and that in low-dose groups was higher than that of control after the third treatment. The expression of MRP, LRP, MDM2, GST, TS, MT, P27 in drug groups was higher than that of control after the third treatment. For the SPC-A-1 cell line, all the low-dose groups and DDP's high-dose group were treated twice by the drugs. The expression of other proteins apart from GST and P27 after the second treatment was lower than that after the first treatment in DDP's high-dose group. The expression of other proteins apart from MRP after the second treatment was higher than that after the first treatment in two to four low-dose groups. 3. The time of the cells double proliferation in high-dose groups was longer than that in low-dose ones. The levels of every protein related to cell proliferation decreased along with cell continue culture. In high-dose groups, the expression of erbB-2 was downregulated along with the times of treatment in the LTEP-a-2 cell line; while in low-dose groups, there was not a rule. The expression of erbB-2 in high-dose DDP group downregulated more greatly than that in low-dose groups in the SPC-A-1 cell line. There was not a rule about the variation of the expression of c-myc in both the cell lines.4. The levels of every protein related to metastasis decreas...