Objective: To establish a multidrug-resistant cell line BEL-7402/5-FU of hepatocellular carcinoma (HCC).
Methods: BEL-7402/5-FU was induced by pulse therapy combined with continuous stepwise exposure to 5-fluorouracil in vitro. MTT assay was used to determine its multidrug resistance (MDR). Biological characteristics of the BEL-7402/5-FU cell line were observed including morphological changes, cell growth curve, population doubling time, plate cloning efficiency, adherence rate, cell cycle distribution, chromosome and tumorigenicity. Accumulation amount of adriamycin (ADM) in cytoplasm was measured by flow cytometry. The protein expression of thymidylate synthase (TS) was evaluated by immuno-cytochemical method.
Results: The acquired MDR cell line of BEL-7402/5-FU was established successfully. The BEL-7402/5-FU cells showed cross-resistance to ADM, vincristine (VCR), methotrexate (MTX) and oxaliplatin (OHP), whereas still sensitive to hydroxycamptothecin (HCPT). The BEL-7402/5-FU cells tended to grow in clusters in vitro. It was found that the population doubling time of BEL-7402/5-FU cells was longer than that of its parental cells. The plate cloning efficiency and the adherence rate of BEL-7402/5-FU cells at the 2nd and 3rd hour were both lower than those of the parental cells. The distributing proportion of BEL-7402/5-FU cells in G(0)/G(1) phase was less than that of the parental cells, whereas the distributing proportion of BEL-7402/5-FU cells in S phase was higher than that of the parental cells. The accumulation amount of ADM in cytoplasm of BEL-7402/5-FU cells was significantly lower while the expression level of TS protein of which was highly up-regulated as compared with those of the parental cells.
Conclusion: Establishment of the human HCC cell line BEL-7402/5-FU might be beneficial to the studies of 5-Fluorouracil acquired MDR mechanisms and the selection of reversal modifiers.