LGALS9 and melanoma: It is reported that addition of recombinant Gal-9 induced apoptosis of various malignant cells, such as hematological malignant cells (Kobayashi et al., 2010, 2015), melanoma cells (Kageshita et al., 2002; Wiersma et al., 2012) and gastrointestinal cells (Tadokoro et al., 2016, 2017; Okura et al., 2018).