Meta-tetrahydroxyphenyl chlorine mediated photodynamic therapy inhibits the migration and invasion of a nasopharyngeal carcinoma KJ-1 cell line.

BACKGROUND/PURPOSE: Different photosensitizer-mediated photodynamic therapy (PDT) has different intracellular cytotoxic cascades. Previous reports showed that 5-aminolevulinic acid (5-ALA)-mediated PDT suppressed the migration and invasion of head and neck cancer cells. Unlike from 5-ALA, which mainly targets the mitochondria of cells, meta-tetrahydroxyphenyl chlorin (m-THPC) mainly accumulates in the endoplasmic reticulum and Golgi complex. Does m-THPC PDT inhibit the migration and invasion of cancer cells? METHODS: The effect of m-THPC PDT with a sublethal dose sufficient to kill around 20% of cells on the migration and invasion of a nasopharyngeal carcinoma KJ-1 cell line was studied by wound healing and Matrigel invasion assays. RESULTS: In the wound healing assay, the migration distance of KJ-1 cells decreased significantly from 0.71 +/- 0.02 mm in the control cells to 0.31 +/- 0.03 mm in the PDT-treated cells 24 hours after light treatment (p < 0.05) and the migration distance also decreased significantly from 1.02 +/- 0.07 mm in the control cells to 0.32 +/- 0.04 mm in the PDT-treated cells 48 hours after treatment (p < 0.05). In the Matrigel invasion assay, the number of the invaded KJ-1 cells in PDT treated group was also statistically significantly less than those without PDT treatment (p < 0.05). CONCLUSION: This study demonstrates that a sublethal dose of m-THPC PDT inhibits the migration and invasion of nasopharyngeal carcinoma cells in vitro.