Figure 4. Targeting of MYCN by miR-34a in vivo.

(A) MYCN, a validated target of miR-34a, mRNA levels were significantly reduced in GD₂-miR34a-NP treated NB1691^luc tumors relative to negative controls (**p<0.001, n=8) (B) qPCR analysis of SK-N-AS^luc tumors did not indicate a statistically significant difference between anti-GD₂-miR34a-NP and anti-GD₂-miRneg-NP treated tumours, potentially because levels of MYCN expression are very low in this cell line. Three SK-N-AS tumors treated with negative control nanoparticles appeared to have somewhat higher expression then the median, although this level of expression is very low compared to MYCN amplified tumors (C) MYCN reduction in NB1691^luc was validated at a protein level by Western Blot and (D) protein suppression was quantified using densitometry. NME1, a validated MYCN target, had reduced mRNA levels in anti-GD₂-miR34a-NP treated NB1691^luc tumors (E) and SK-N-AS^luc tumors (F) relative to negative controls (*p<0.05, n=8), as evaluated by qPCR.