NT5E and head and neck squamous cell carcinoma: CD73 overexpression in tumor cells is associated with the pathogenesis (Yan et al., 2019), progression (Yu et al., 2018), and poor prognosis in several types of cancers, including HNSCC (Ren et al., 2016a), triple-negative breast cancer (Loi et al., 2013), oral squamous cell carcinoma (Ren et al., 2016b), and high-grade serous ovarian cancer (Turcotte et al., 2015), among others.