Abstract
Purpose :
MiR-34a has been shown to inhibit the proliferation and migration of uveal melanoma. LGR4 has been shown invovled in the regualtion of several kinds of tumors, its role in uveal melanoma has not been uncovered. Here we sought to evaluate the interplay of miR-34a and LGR4.
Methods :
The expression level of LGR4 in primary uveal melanocyte and uveal melanoma cell lines M23, M17 and SP6.5 were compared with western blot and immunofluorescence imaging. Target of LGR4 by miR-34a was confirmed by western blot. We then performed in vitro scratch and transwell assay to evaluate the migration activity of uveal melanoma cells using LGR4 knockdown and transfection of miR-34a. Similarly, martrigel transwell assay was used to measure the invasive potential of uveal melanoma cells. Furthermore, Epithelial–mesenchymal transition (EMT) molecules were tested with western blot and immunofluorescence imaging to elucidate underlying mechanisms.
Results :
LGR4 is significantly upregulated in uveal melanoma cell lines. LGR4 is a direct target of miR-34a in uveal melanoma cells. Transfection of miR-34a or knockdown of LGR4 attenuates the migrative and invasive potential of uveal melanoma cells. There is a decrease in the expression of mesenchymal markers N-Cadherin, Vimentin and Snail accompanyed with increase of epithelial marker E-Cadherin following miR-34a introduction and knockdown of LGR4.
Conclusions :
MiR-34a can exert a negative control of LGR4 to inhibit the migration and invasion of uveal melanoma cells. Both miR-34a and LGR4 helps control the aggressiveness of uveal melanoma through the regulation of EMT process.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.