Genome-wide analysis of ATF4 interaction sites by chromatin immunoprecipitation (ChIP) sequencing revealed that among ATF4 target genes was <i>KLF9</i> (Kruppel-like factor 9), which induces MTC apoptosis.
Forced ATF4 expression decreased survival of MTC cells and blocked the activation of RET downstream signaling pathways (phosphorylated ERK, phosphorylated AKT, and p70S6K).