NGF and neoplasm: Overall, the results of the expression analysis based on the 5-ALA FGS approach indicate that the tumor margins are characterized by low levels of KDM5C, HIF1A, p75NTR, and NGF, whereas the tumor border regions (TR) are significantly enriched for these markers, and, in line with the highly hypoxic features of the tumor core, it is mainly characterized by increased HIF1A and p75NTR expression.