ESR1 and head and neck squamous cell carcinoma: Previous researches indicated that BRCA1 in module 1 was associated with risk of estrogen-receptor-negative breast cancer (Milne et al., 2017), NFE2L2 in module 3 was related with cell multisystem disorder (Huppke et al., 2017), and TP53 in module 5 was related with human immunodeficiency virus-related head and neck squamous cell carcinoma (Gleber-Netto et al., 2018).