摘要
Objective： To discuss the difference between multi-drug resistant cell line H460/Gem and its parental cell NCl-H460 on the basis of establishment of human gemcitabine-resistant cell line H460/Gem so as to elaborate the possible mechanisms of gemcitabine resistance. Methods： Human gemcitabine-resistant non-small cell lung cancer cell line H460/Gem was established by 2/3 clinical serous peak concentration gemcitabine intermittent selection from its parental cell human large cell lung carcinoma cell line NCl-H460 which was sensitive to gemcitabine. During the course of inducement, we had monitored their morphology, checked their resistance indexes and resistant pedigree by MTT method, gathered their growth curves and calculated their doubling time, examined their DNA contents and cell cycles by FCM; at the same time, we had measured its expressions of P53, EGFR, c-erb-B-2, PTEN, PCNA, c-myc, VEGF, MDR-1, Bcl-2, nm23, MMP-9, TIMP-1, CD44v6 proteins via immunocytochemistry staining, RRM1 and ERCC1 mRNA by real-time fluorescent quantitative-PCR. Results： The resistance index of H460/Gem＇ cells （the deputy of cells in the process of inducement） to gemcitabine was 1.201, and the cell line also exhibited cross-resistance to paclitaxol, fluorouraci, etoposide, cisplatin and oxaliplatin, but kept sensitivity to vinorelbine and taxotere. The doubling time of H460/Gem＇ cells was longer and figures in G0-G1 phase was decreased than that of NCl-H460 cells. Compared with NCl-H460 cells, H460/Gem＇ cells had achieved TIMP-1 protein expression emerged, nm23 protein expression enhanced, VEGF and MMP-9 protein expressions reduced, and CD44v6, P53 protein expressions vanished, but expressions of EGFR, c-erb-B-2, PTEN, PCNA, c-myc, MDR-1, Bcl-2 proteins and RRM1, ERCC1 mRNA changed trivially. The resistance index of H460/Gem cells to gemcitabine was 1.644, and the ceil line also exhibited cross-resistance to fluorouraci, cisplatin and oxaliplatin, but kept sensitivity to paclitaxol, vinorelbine, taxotere, and etoposide. The doubling time of H460/Gem cells was longer and figures in G0-G1 phase was decreased than those of NCl-H460 cells. The farther studies indicated that, compared with NCl-H460 cells, the expressions of MDR-1, nm23 and Bcl-2 proteins in H460/Gem cells had been enhanced, c-erb-B-2 protein expression emerged, P53, MMP-9 and VEGR protein expression had been weakened, but the changes of PTEN, PCNA, c-myc, TIMP-1, EGFR, CD44v6 protein, RRM1 mRNA and ERCC1 mRNA expressions were trivial. Furthermore, compared with its parental cells, H460/Gem cells were mixed with giant cells of different sizes that were larger and more irregular. Conclusion： The human gemcitabine-resistant non-small cell lung cancer cell line H460/Gem had achieved multi-drug resistance and great changes of biological characters compared with its parental cells. And these changes possibly participated in the formation of multidrug resistance.
基金
Capital Medical Developmental Foundation (No. 2003-3028)
