Abstract:

Objective

To explore the effect of lymphotactin (XCL1) on epirubicin sensitivity of human breast MCF-7 cells and invasion and metastasis ability of cells.

Methods

The MCF-7 cells were divided into four groups: the control group (MCF-7 NC) and three experimental groups (MCF-7 E group treated with epirubicin, MCF-7 XCL1 group treated with XCL1 and MCF-7 XCL1+E group treated with XCL1 plus epirubicin). CCK-8 assay and plate clone formation assay were used to measure the epirubicin sensitivity of MCF-7 cells after XCL1 treatment. Transwell assay was used to evaluate the migration and invasion ability of MCF-7 cells. The expressions of ezrin and phosphorylated ezrin (p-ezrin) in the control group and MCF-7 XCL1 group were determined by immunofluorescence assay. The expressions of E-cadherin, ezrin and p-ezrin in four groups were detected by Western blot. The growth inhibition rates of cells were compared using variance analysis of factorial design. The mean values between two groups were compared using t test, the mean values among multiple groups were compared using single factor analysis of variance. Pairwise comparison was performed using LSD method.

Results

After 2-week treatment of XCL1, the inhibitory effect of epirubicin on MCF-7 cells was decreased (group comparison: F=23.780,P＜0.001;different concentrations of epirubicin:F=160.602,P ＜0.001; no interaction between grouping and concentration of epirubicin: F=1.565, P=0.208). The clone formation rates of MCF-7 NC, MCF-7 XCL1, MCF-7 E and MCF-7 XCL1 + E groups were(15.63±0.61)%, (19.47±1.94)%, (7.77±0.71)% and (12.37±1.55)%, respectively, indicating a significant difference (F=41.925, P＜0.001). The number of cells penetrating the membrane in the MCF-7 XCL1 group was significantly higher than that in the MCF-7 NC group (migration: 180.00±20.42 vs 88.00±7.00, t = -7.382, P = 0.002; invasion: 176.33±8.02 vs 90.33 ±12.90, t = -9808, P = 0.001).Immunofluorescence assay showed that the expression of p-ezrin protein was significantly increased in MCF-7 cells after XCL1 stimulation (MCF-7 XCL1:1.08±0.12, MCF-7 NC:0.65 ± 0.11, t=-4.528, P=0.011).Western blot analysis showed that the expressions of E-cadherin and p-ezrin among four groups were significantly different (F=6.317,48.517, both P＜0.050), while there was no significant difference in ezrin expression (F=0.868, P=0.497). Compared with the control group(1.10 ± 0.09), the expression of E-cadherin in MCF-7 E group, MCF-7 XCL1 group and MCF-7 XCL1 + E group was decreased (0.65±0.22,0.67±0.14,0.71±0.11, all P＜0.05). The expression of p-ezrin in MCF-7 XCL1 group and MCF-7 XCL1+E group (0.93±0.10,1.28±0.15) was increased compared with control group (0.37±0.07, both P＜0.050).

Conclusion

XCL1 can reduce the epirubicin sensitivity of human breast cancer MCF-7 cells and increase the ir invasion and metastasis ability of cells.

Key words: Breast neoplasms, Lymphokines, Epirubicin, Drug resistance, neoplasm, Ezrin