RSPO2 and nasopharyngeal carcinoma: Interestingly, Wang Z. et al. (2021b) demonstrated that RSPO2, a member of the R-spondin-2 protein family which plays an essential role in stem cell survival, when silenced inhibits the tumorigenicity of nasopharyngeal carcinoma via the zinc and ring finger 3 (ZNRF3)/Hedgehog-Gli1 axis.