Fig. 4: Characterization of NR Cells and the function of SOX2 and NTRK2.

A GSEA results from DEs between NR cells and Keratinized cells in the UT dataset. B Violin plots showing the expression or activity score of genes (SOX2 and CD44) and gene sets (Stemness, p-EMT, EMV-IV, and Hypoxia). Wilcoxon signed-rank test was performed. C Images showing the size of tumorspheres. Cells with different TrkB abundance were seeded for this tumorsphere-forming assay. D Bar plots showing the numbers of tumorspheres (size over 10 µm). Cells with different TrkB abundance were seeded for this tumorsphere-forming assay. E Fluorescent immunostaining of tumorspheres showing the existence of the SOX2 and TrkB. F Images showing the size of tumorspheres. TrkB-high NPC43 or C17 cells undergo SOX2 or NTRK2 knockdown before seeding for the tumorsphere-forming assay. G Bar plots showing the numbers of tumorspheres (size over 10 µm). TrkB-high NPC43 or C17 cells undergo SOX2 or NTRK2 knockdown before seeding for tumorsphere-forming assay. H Heatmap showing the correlation of SOX2, CD44, and NTRK2 with EMT-related gene sets. Three gene sets defined from three different studies consistently show higher correlation with NTRK2. I Images showing the wound healing assay with different cells. NPC43 cells were knocked down with a shRNA vector. NTRK2-KD-sh shows slower migration compared to the control. J Violin plots showing ELF3 expression as a marker of differentiated cells in NPC43. K qPCR analysis showing increased expression of ELF3 and BZLF1 following NTRK2 knockdown and lytic induction treatment. Compared to NC-sh of UT, paired t-test p-values were less than 0.0383 for ELF3 and 0.00942 for BZLF1. L FACS analysis of Zta+ cells indicating an increased proportion of cells entering the lytic activation state after NTRK2 knockdown. A two-proportion z-test showed a p-value smaller than 10⁻⁵.