[The building of multiple drug resistant human laryngeal cancer cell line and its characteristics].
OBJECTIVE
To build the multiple drug resistant human laryngeal cancer cell line and investigate its characteristics.


METHODS
Human laryngeal cancer cells were exposed in stepwise escalating concentration of Taxol until the resistant cell line was developed. The IC50 and the resistance folds of multidrug resistance were detected by an ATP assay. The differences of cell cycle distribution, apoptosis, and Rhodamine accumulation between Hep-2 and Hep-2T cells were studied through flow cytometry. The MDR1 and MRP1 gene were detected through realtime quantitative RT-PCR, and the corresponding protein was detected through western-blotting.


RESULTS
A multidrug resistance cell line-Hep-2T induced by Taxol was effectively developed, whose drug resistance was 104 times that of Hep-2 cells. Doxorubicin, Gemcitabine, 5-Fu, Cisplatin all increased the drug resistance by 46.78, 1.95, 2.50, 1.05 folds. The cell cycle distribution altered. The apoptosis of Hep-2 cells was quite greater than that of Hep-2T cells (45.32% vs 4.26%, P < 0.01, flow cytometry), (54.47 +/- 48.95 vs 9.84 +/- 12.53 P < 0.01, hoechst staining) after Hep-2 and Hep-2T exposed to Taxol at IC50 to Hep-2. The copy ratio of MDR1/GAPDH mRNA of Hep-2T was 64.2 +/- 36.7 times that of Hep-2 (P < 0.05), while MRP1/GAPDH of Hep-2T was only 1.20 +/- 0.09 folds more than that of Hep-2 (P < 0.05). The proteins of MDR1/P-gp were greatly over expressed in Hep-2T cells compared with Hep-2 cells (P < 0.01) whose was in the same trend (P < 0.05), while the elevated expression of MRP1 was lower than that of MDR1/P-gp.


CONCLUSIONS
When considering the possible methods to reverse MDR of SCCHN, more emphasis should be laid on MDR1/P-gp, and when combining this with chemotherapy the non-P-gp substrate chemotherapeutic agents should be considered. At the same time, more attention should be paid to the changes of cell cycle distribution during the drug selection.
Department of Otolaryngology-Head and Neck Surgery, Shanghai Jiaotong University Affiliated First People's Hospital, Shanghai, 200080, China.
Li
L
Li
Pin
P
Dong
Yi
Y
Wan
Chengzhi
C
Xu
Li
L
Chen
D018929:Cell Culture Techniques / Q000379:methods*; D045744:Cell Line, Tumor / Q000187:drug effects*; D018432:Drug Resistance, Multiple / Q000187:drug effects*; D019008:Drug Resistance, Neoplasm / Q000187:drug effects*; D006801:Humans; D017239:Paclitaxel / Q000494:pharmacology*
D017239:Paclitaxel