Initial in vivo research focused on the role of HMT in cancer and its functional consequences (Tan et al., 2015; Bajzikova et al., 2019) and possible modulation of resistance to cancer therapy (Osswald et al., 2015; Moschoi et al., 2016), and later on regulation of cancer-related immune responses (Saha et al., 2022). The gene discussed is HNMT; the disease is cancer.