SLC3A2 and head and neck squamous cell carcinoma: Intriguingly, SLC3A2 was shown to mediate radioresistance and to be a negative prognostic factor in HPV-negative HNSCC cells and tumors in some recent reports [58,66,68], whereas our overall survival data rather support the finding of a generally reduced expression and of a negative prognostic role more evident in HPV-positive OPSCC as reported by Rietbergen et al. [65] (Figure 7).