Treatment failure in high risk
neuroblastoma (NB) is largely due to the development of
chemotherapy resistance. We analyzed the gene expression changes associated with exposure to
chemotherapy in six high risk NB
tumors with the aid of the Connectivity Map bioinformatics platform. Ten therapeutic agents were predicted to have a high probability of reversing the transcriptome changes associated with
neoadjuvant chemotherapy treatment. Among these agents, initial screening showed the
EWS-FLI1 and
RNA helicase A interaction inhibitor
YK-4-279, had obvious cytotoxic effects on NB cell lines. Using a panel of NB cell lines, including MYCN nonamplified (SK-N-AS, SH-SY5Y, and CHLA-255), and MYCN amplified (NB-19, NGP, and IMR-32) cell lines, we found that
YK-4-279 had cytotoxic effects on all lines tested. In addition,
YK-4-279 also inhibited cell proliferation and anchorage-independent growth and induced cell apoptosis of these cells.
YK-4-279 enhanced the cytotoxic effect of
doxorubicin (Dox). Moreover,
YK-4-279 was able to overcome the established chemoresistance of LA-N-6 NB cells. In an orthotopic xenograft NB mouse model,
YK-4-279 inhibited NB
tumor growth and induced apoptosis in
tumor cells through PARP and
Caspase 3 cleavage in vivo. While
EWS-FLI1 fusion protein is not frequently found in NB, using the R2 public database of
neuroblastoma outcome and gene expression, we found that high expression of EWSR1 was associated with poor patient outcome. Knockdown of EWSR1 inhibited the oncogenic potential of
neuroblastoma cell lines. Taken together, our results indicate that
YK-4-279 might be a promising agent for treatment of NB that merits further exploration.