[Role of CCL21/CCR7 in invasion of colorectal carcinoma cell line SW480].

BACKGROUND AND OBJECTIVE

Chemokine receptor CCR7 is up-regulated in gastrointestinal carcinomas and is significantly associated with lymphatic invasion and lymph node metastasis. This study was to investigate the role and mechanism of CCL21/CCR7 in invasion of colorectal carcinoma cell line SW480.

METHODS

The invasive capacity of SW480 cells was examined using Wound healing assay and Transwell assay. Expression of matrix metalloproteinase-9 (MMP-9) was measured by Western blot. SW480 cells were pre-incubated with CCL21 for 2 h before exposure to VP-16 (20 ng/mL). Cell proliferation was measured using MTT assay. Cell apoptosis was analyzed by flow cytometry and Hoechst33258 staining.

RESULTS

Compared to the control group, more cells in the CCL21 treatment group migrated into the gap at same time points; the count of SW480 cells penetrating through the membrane after the treatment of 100ng/mL CCL21 increased significantly [(113+/-7) vs. (48+/-4)] (P<0.05); and the relative expression of MMP-9 in the CCL21 treatment group was enhanced evidently [(0.83+/-0.02) vs. (0.38+/-0.01)] (P<0.05). Although CCL21 alone did not promote proliferation of SW480 cells, pre-incubation of cells with 100ng/mL CCL21 attenuated the inhibitory effect of VP-16 on proliferation of SW480 from 68.3% to 47.4%, and reduced the apoptotic rate from (65.2+/-5.2)% to (48.7+/-3.1)%.

CONCLUSION

CCL21 enhances the invasive ability of SW480 cells, induces MMP-9 expression, and promotes the survival of SW480 cells under the suboptimal circumstance in vitro.