A tumor’s gene expression profile may also contain information about potential therapeutic targets, such as the ERBB2 gene coding for receptor tyrosine-protein kinase erbB-2 (HER2 receptor) that is overexpressed in several classes of cancers, including subtypes of breast, ovarian, gastric, and lung cancers (Slamon et al., 1989; Konecny et al., 2003; Yan et al., 2015; Oh and Bang, 2020). Here, ERBB2 is linked to lung cancer.