NGFR and esophageal squamous cell carcinoma: Based on the results above, LY294002 treatment reverse the expression of PI3K, p-Akt (ser473) and p75NTR in Eca109-psb and TE-1-psb cells, and this further demonstrated that the activation of PI3K/Akt signaling pathway, induced by HPV16 E6-E7, plays a vital role in maintaining CSCs phenotypes in ESCC cells [30].