SELENOK and metastatic melanoma: In vivo investigations were conducted using the Grm1-Tg transgenic mouse strain that develops spontaneous metastatic melanoma, which was crossed with SELENOK−/− mice to generate the following littermates: Grm1-Tg/SELENOK−/−, Grm1-Tg/SELENOK−/+, Grm1-Tg/SELENOK+/+.