The hyaluronan synthesis inhibitor 4-methylumbelliferone inhibits cell proliferation and wound healing on in vitro endometriosis models

Abstract

Objectives: The aim of this study was to evaluate the effect of 4-methylumbelliferone (4MU) on cell proliferation, wound healing process and gelatinase activity on human endometrial stromal (t-HESC) or epithelial (ECC-1) cell lines. Methods: t-HESC and ECC-1 endometrial cell lines were stimulated with different concentrations of 4MU. Cell proliferation was evaluated after 24hs with the cell proliferation reagent WST-1. The area of a scratch closed by the t-HESC was calculated in a wound healing assay, for this purpose photomicrographs were taken at time 0h and time 20hs; and the gelatinase activity in conditioned media of t-HESC was evaluated by zimography. Only p<0.05 was considered as statistically significant. Results: After 24hs of treatment the cell proliferation of ECC-1 was significantly inhibited by 0.5, 1 and 2 mM 4MU (p<0.01, p<0.001 and p<0.01, respectively versus control), whereas cell proliferation of t-HESC was significantly inhibited by 2 and 4 mM 4MU (p<0.01 versus control). Already at 0.5 mM 4MU, the migration of t-HESC cells was significantly inhibited and the scratch was closed in a low percentage (p<0.01 for 0.5 and 1 mM 4MU versus control, p<0.001 for 2 and 4 mM 4MU). Preliminary results of MMP-2 and MMP-9 activities revealed that these gelatinases would not be modulated after 24hs of 4MU treatment. Conclusion: Endometriosis is a benign gynecological disease affecting 10% of women of reproductive age, characterized by the presence of endometriotic foci outside the uterine cavity. Previous studies from our laboratory demonstrated a strong antiangiogenic activity of 4MU. The present results are, in part, in agreement with those reported by other authors. Given these and our background on targeting hyaluronan on endometriosis models we are encouraged to continue investigating on this path to understand the implication of hyaluronan synthesis inhibition on the migratory capacity of the cells and which molecules are involved in this matter.