C9orf72 and neuroblastoma: To explore this possibility, we transduced BE(2) M17 human neuroblastoma cells with lentiviral constructs expressing shRNAs targeting C9orf72 transcripts 2 and 3, MAPT and GRN. qPCR experiments on cDNAs from the transduced cells showed a clear influence on expression of C9orf72 transcripts 2 and 3 after knock down of MAPT and GRN separately compared to scrambled controls (Fig. 7).