Litchi Seed Aqueous Extracts play a role in suppression of epithelial-mesenchymal transition, invasion and migration in breast cancer cells

Abstract

We carried out this study to unravel the function of Litchi Seed Aqueous Extracts (LSAE) on biological functions of breast cancer (BC) cells. MTT assay was adopted to measure proliferation of BC cells (MCF7, BT474 and MDA-MB-231) and normal mammary cells (MCF10A) under different time points (24, 48 and 72 h) and different concentrations (50, 100, 200 and 400 μg/mL). MCF-7 cells were selected for subsequent experiments and were grouped into blank group, negative control (NC) group, low-, medium- and high-dose LSAE (L-LSAE, M-LSAE, H-LSAE) groups. Cell viability, invasion, migration and apoptosis were measured by functional assays. Low dosage of LSAE (50 and 100 μg/mL) enhanced proliferation of MCF10A cells, while high dosage of LSAE (200 and 400 μg/mL) suppressed proliferation of MCF10A cells. The proliferation inhibition rate in BT474 and MDA-MB-231cells was increased relative to that in MCF7 cells. MCF-7 cells in the L-LSAE, M-LSAE and H-LSAE groups were rounded and epithelial-like, in which cell survival rate, epithelial-mesenchymal transition (EMT), invasion and migration abilities were reduced versus the blank and NC groups. The tendency in the H-LSAE group was substantially obvious than those in the L-LSAE and M-LSAE groups (both P < 0.05). We found that LSAE is able to inhibit EMT, invasion and migration in BC cells based on concentration and time.

Keywords: Aqueous extracts; Breast cancer; Epithelial-mesenchymal transition; Invasion; Litchi seed; Migration.

Figure 1.

Sensitivity of BC cells and normal mammary cells to LSAE. Note: Repetitions = 3, one-way ANOVA was used for comparisons among multi-groups and LSD-t was used for pairwise comparisons after one-way ANOVA; *, compared with MCF-7 cells subject to the same concentration of LSAE; BC, breast cancer; LSAE, Litchi seed aqueous extracts.

Figure 2.

Inhibition of LSAE with different concentrations on the proliferation of MCF-7 cells. Note: LSAE, Litchi seed aqueous extracts.

Figure 3.

Morphology of MCF-7 cell in the blank group, NC group, L-LSAE, M-LSAE and H-LSAE group under the observation of a microscope (× 100).

Figure 4.

Expression of EMT biomarkers E-cadherin and Vimentin in MCF-7 cells. Note: A, relative expressions of E-cadherin and Vimentin in MCF-7 cells by Western blot assay; B, statistical analysis of protein expression of E-cadherin and Vimentin; repetitions = 3, one-way ANOVA was used for comparisons among multi-groups and LSD-t was used for pairwise comparisons after one-way ANOVA; *, compared with the blank group, P < 0.05; #, compared with the L-LSAE group, P < 0.05; &, compared with the M-LSAE group, P < 0.05.

Figure 5.

Cell survival rate of MCF-7 cells among the blank group, NC group, L-LSAE group, M-LSAE group and H-LSAE group. Note: Repetitions = 3, one-way ANOVA was used for comparisons among multi-groups and LSD-t was used for pairwise comparisons after one-way ANOVA; *, compared with the blank group, P < 0.05; #, compared with the L-LSAE group, P < 0.05; &, compared with the M-LSAE group, P < 0.05.

Figure 6.

Cell apoptosis of MCF-7 cells among the blank group, NC group, L-LSAE group, M-LSAE group and H-LSAE group. Note: A, cell apoptosis of MCF-7 cells by flow cytometry, B, comparison on cell apoptosis rate of MCF-7 cells; repetitions = 3, one-way ANOVA was used for comparisons among multi-groups and LSD-t was used for pairwise comparisons after one-way ANOVA; *, compared with the blank group, P< 0.05; #, compared with the L-LSAE group, P< 0.05; &, compared with the M-LSAE group, P< 0.05.

Figure 7.

Cell invasion ability of MCF-7 cells among the blank group, NC group, L-LSAE group, M-LSAE group and H-LSAE group. Note: A, cell invasion ability detected by Transwell assay; B, comparison on cell invasion ability; repetitions = 3, one-way ANOVA was used for comparisons among multi-groups and LSD-t was used for pairwise comparisons after one-way ANOVA; * compared with the blank group, P< 0.05; #, compared with the L-LSAE group, P< 0.05; &, compared with the M-LSAE group, P< 0.05

Figure 8.

Cell migration ability of MCF-7 cells among the blank group, NC group, L-LSAE group, M-LSAE group and H-LSAE group. Note: A, cell migration ability of MCF-7 cell by scratch test; B, cell migration ability of MCF-7 cells; repetitions = 3, one-way ANOVA was used for comparisons among multi-groups and LSD-t was used for pairwise comparisons after one-way ANOVA; *, compared with the blank group, P< 0.05; #, compared with the L-LSAE group, P< 0.05; &, compared with the M-LSAE group, P< 0.05.