Pharmacological drug screening to inhibit uveal melanoma metastatic cells either EGF-R, MAPK, mTOR or PI3K.

AIM

To screen five potential pharmacological substances specifically targeting EGF-R, MAPK, mTOR, or PI3K for their antiproliferative effects, possible impact on cell viability, as well as cell death rates on three different uveal melanoma metastasis cell lines .

METHODS

Three different uveal melanoma metastasis cell lines (OMM2.5, OMM2.3, and OMM1), that originated from human hepatic and subcutaneous metastasis, were exposed to inhibitors of different targets: erlotinib (EGF-R), everolimus (mTOR), selumetinib (MAPK), trametinib (MAPK) or the alkylphosphocholine erufosine (PI3K). Cell viability was assessed with a 2,3-bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide (XTT) dye reduction assay after 24h of treatment. Antiproliferative effects were evaluated separately after a 72-hour incubation of the cells with the pharmacological substance. Subsequently, the IC was calculated. Tumor cell death was investigated using a double stain apoptosis detection assay.

RESULTS

Selumetinib, trametinib, and erufosine significantly decreased cell viability of all OMM cell lines (<0.04). In addition, selumetinib and trametinib showed a significant inhibition of cell proliferation (<0.05). Everolimus and erlotinib solely inhibited cell proliferation at the used concentrations (<0.05). Besides an increase of necrotic cells after erufosine treatment (<0.001), no changes in the number of dead cells for the other substances were observed.

CONCLUSION

The preliminary drug screening demonstrates five new candidates, successfully targeting the canonical MAPK/ERK and PI3K/AKT/mTOR pathways in uveal melanoma metastasis cells . Hence, these findings provide an experimental basis to explore future single or combined therapy strategies for metastatic uveal melanoma.