Immunofluorescence analysis on SH‐SY5Y cells was performed as previously described 54. Briefly, after fixation with 4% Paraformaldehyde (PFA), cells were permeabilized in 0.2% Triton X100 and blocked by incubation with 10% normal goat serum (NGS, Gibco, Invitrogen, Milan, Italy) for 1 hr at room temperature (RT). The primary incubation was performed, overnight at 4°C, with the following antibodies: rabbit anti‐p75 (1:500, Chemicon Int. Inc., USA), mouse anti‐S‐100 (1:100; Sigma‐Aldrich, Saint Louis, Missouri, USA), rabbit anti‐HIF1A (1:200; Sigma‐Aldrich, Saint Louis, Missouri, USA), mouse anti‐Cx43 (1:150, Cell Signaling, Danvers, Massachusetts, USA) and rabbit β‐tubulin (1:200, Cell Signaling, Danvers, Massachusetts, USA).