Figure 1.

MYCN expression regulates EVs protein cargo in neuroblastoma cells. (a) Western blot analysis demonstrating the conditional expression of MYCN in TET21-N cells in the presence (MYCN-off) or absence (MYCN-on) of doxycycline. Protein lysates from the MYCN-amplified cell line KELLY were used as a positive control. β-actin was used as a loading control. (b) Heat map analysis showing a drastic difference in protein expression—either upregulated (red) or downregulated (green)—in EVs secreted by TET21-N cells expressing or non-expressing MYCN. Mass spectrometry analysis was conducted in triplicate samples (biological replicates). (c) Pathway analysis of the proteins identified in EVs from MYCN-positive and -negative TET21-N cells. The protein groups enriched in the MYCN-positive condition are evidenced by the red circles. (d) Western blot analysis of EVs and total cell lysates isolated from the TET21-N cells. The EV marker CD63 was used as a loading control. An asterisk indicates the hexokinase II protein band at 105 kD, whereas the 125 kD band enriched in vesicles is of spurious nature.