RESUMO
<p><b>OBJECTIVE</b>To observe the inhibitory effect of gefitineb on the proliferation and its inducing effect on the apoptosis of mouse I-10 Leydig testicular cancer cells in vitro.</p><p><b>METHODS</b>We treated I-10 Leydig testicular cancer cells of mice with gefitineb at 0, 1.25, 2.5, 5, 10, 20, and 40 µmol/L. Then we determined the inhibitory effect of gefitineb on the growth of the cells by MTT, detected their early and late apoptosis by Annexin V-FITC/propidium iodide double staining and Hoechst 33258 nuclear staining, respectively, and observed the expressions of apoptosis-related proteins Bcl-2, Bax and caspase 3/9 by Western blot.</p><p><b>RESULTS</b>Compared with the blank control group, gefitineb significantly inhibited the proliferation of the I-10 cells at 10 and 20 µmol/L (P < 0.05). The survival rate of the cells was (32.4 ± 2.8)% (P < 0.01) and their early and late apoptosis rates were (26.7 ± 4.2)% and (59.33 ± 10.2)% in the 40 µmol/L group, significantly different from those in the control (P < 0.05 and P <0.01). In comparison with the blank control group, gefitineb at 10, 20, and 40 µmol/L increased the expression of pro-apoptotic protein Bax by (41.9 ± 7.1), (60.1 ± 9.8), and (69.0 ± 11.3)% (all P < 0.05), decreased that of apoptosis-inhibitory protein Bcl-2 by (50.3 ± 8.9), (63.9 ± 6.9), and (88.7 ± 13.9)% (all P < 0.05), and elevated that of the cleft proteins caspase-3 by (69.0 ± 6.9)% (P < 0.05), (71.5 ± 8.1)% (P < 0.05), and (110.9 ± 14.2)% (P < 0.01) and caspase-9 by (51.8 ± 4.9), (54.7 ± 6.7), and (43.8 ± 11.8)% (all P < 0.05).</p><p><b>CONCLUSION</b>Gefitineb can increase the cytotoxicity of I-10 Leydig testicular cancer cells of mice and induce their apoptosis via the mitochondria-mediated apoptosis signaling pathway.</p>