The Potentiation Of Chemotherapy And Mechanism With ATRA And VitD₃ Of Human Lung Cancer Cells

OBJECTIVE:To observe the effect of the potentiation of chemotherapy with ATRA and VitD3 of human lung cancer cells;To observe the relationship between the expression of the drug- resistance genes and sensitivity of the chemotherapy;To observe the change of expression of drug- resistance gene and the effect of cell proliferation and apoptosis after treatment with ATRA and VitD3.To explore the mechanism of the potentiation of chemotherapy with ATRA and VitD3 of lung cancer cells.METHODS:The lung cancer primary cells and lung adenocarcinoma cell lines A549 was used in the test. MTT colorimetric assay was applied to detect the sensitivity of 8 chemotherapy drugs and to detect the IC50 of cisplatin of the lung adenocarcinoma cell lines A549 before and after treatment with ATRA and VitD3.RT-PCR was applied to observe the expression of the drug- resistance genes.The flow cytometry was applied to observe the effect of the cell proliferation and apoptosis before and after treatment with ATRA and VitD3 in the lung adenocarcinoma cell lines A549. Immunohistochemical method was applied to observe the expression of the genes related to apoptosis.RESULTS:1.The percentage of positive expression of MRP, LRP was 54.7%, 58.5% in NSCLC cells.The lung cancer cells of MRP negative expression was found significantly sensitivity to ADM, VP-16, VCR than those of MRP positive expression;but not found significantly sensitivity to CBP, DDP, MMC, MTX, 5-Fu. The lung cancer cells of LRP negative expression was found significantly sensitivity to CBP, DDP, ADM, VP-16, VCR than those of LRP positive expression;but notfound significantly sensitivity to MMC, MTX, 5-Fu.The expression of MRP, LRP genes was reversed after 1 μ mol ATRA or VitD3 treatment.The human lung cancer cells was found more sensitivity to chemotherapy after 1 μ mol ATRA or VitD3 treatment.2.The lung cancer cells growth was inhibited significantly after 1 μ mol ATRA or VitD3 treatment.The cells arrest in G0/G1 phase after 1 μ mol ATRA or VitD3 treatment.The cells arrest could easy to be killed together by drugs of chemotherapy.3. 1 μ mol ATRA or VitD3 could increase the expression of Fas/FasL gene and decrease the expression of Bcl-2 gene in lung cancer cells,and could induced the apoptosis of lung cancers.4. All of the effect of ATRA and VitD3 were synergistic.CONCLUSIONS:1 μ M ATRA or VitD3 can increase the chemosensitivity of lung cancer cells by regulating the expression of apoptosis genes and drug-resistant genes and inhibiting the cell cycle progress,and the effect of ATRA and VitD3 were synergistic.