| Objective To investigate the effects of the lanthanum compounds on proliferation, apoptosis, migration and invasion activity of human cervical cancer cell in vitro which will help to explore a new anti-cervical cancer drug and to provide experimental data for cervical cancer treatment with the rare earth compounds.Methods Cervical cancer HeLa cells cultured in vitro were divided into two groups:experimental group and control group. In experimental group, the cells were respectively treated with lanthanum chloride at different concentrations,5,50 and 100μmol/L. The cells in the control group were not treated with lanthanum chloride. The cell growth was observed by inverted microscope and the morphology changes of the cells were observed by the laser scanning confocal microscope(LSCM). Proliferation of the cervical cancer cells in the two groups was detected by methyl thiazolyl tetrazolium(MTT) test; apoptosis rate was analyzed by flow cytometry (FCM). Cell migration test was applied to observe the effect of lanthanum chloride on migration. Cell invasion test was applied to observe the effect of lanthanum chloride on invasion. Reverse transcription-polymerase chain reaction (RT-PCR) was employed to evaluate the effects of lanthanum chloride on proliferation, anti-apoptosis, migration and invasion-related genes, such as cyclinDl, A20 and MMP-9. In addition, the effects of lanthanum chloride on cyclinD1 protein expression of Hela cells were detected by laser scanning confocal microscope (LSCM).Results Cell growth was observed with an inverted microscope:with the increase of the lanthanum chloride concentrations, the cell density of the experimental groups reduced, granule in cytoplasm of experimental groups increased, color intensifying and intercellular space enlarged; some cells became rounding and dead, floating in the culture media; the exfoliated cells increased gradually. In the control group, the cells grew adherently, with clear morphology and plump cytoplasm, and adjacent cell grew in lamellar. Observed with laser scanning confocal microscope (LSCM):the nuclear chromatin condensated and marginated with the volume of nuclear decreased in experimental groups. With the increase of the lanthanum chloride concentrations, nuclei in the experimental groups became pyknotic and then underwent karyorrhexis. However, the nuclear of the cells in control group were inact. The growth inhibition rates of lanthanum chloride groups (5,50,100μmol/L) were 24%,51%,78%, respectively, each was significantly higher than that of the control group (P<0.05); The apoptosis rates of lanthanum chloride group were (4.91±0.39) %,(7.30±0.71)%,(13.48±0.92)%, respectively, which were all significantly higher than that of the control group [(0.89±0.11)%, P<0.01]. The migration ability of the cells was also decreased by the treatment of lanthanum chloride, the number of migrated cells in lanthanum chloride groups were 22.25±4.35,12.00±3.16,7.75±2.63 respectively, which were all significantly lower than that of the control group (41.25±5.38, P<0.01). The invasion ability of the cells was also decreased by the treatment of lanthanum chloride, the number of invaded cells in lanthanum chloride groups were 11.00±1.41,2.25±1.71,0.75±0.96 respectively, which were all significantly lower than that of the control group (22.50±1.71, P<0.01). The expression of proliferation, anti-apoptosis, migration and invasion-related genes, cyclinDl, A20 and MMP-9, were all decreased by the treatment of lanthanum chloride in a dose-dependent manner. Furthermore, the protein expression of cyclinDl was significantly reduced by laser scanning confocal microscope (LSCM).Conclusion Lanthanum chloride can inhibit cervical cancer cells proliferation and migration, invasion and induce apoptosis in vitro by down-regulating cyclinDl, A20, and MMP-9 expressions, which suggests a potential clinical application of lanthanum chloride in cervical cancer therapies. |
