Biologically, impairment of KLF11-mediated HP1-HMT recruitment abolishes tumor suppression, providing direct evidence that HP1-HMTs act in a sequence-specific manner to achieve this function rather than its well characterized binding to methylated chromatin without intermediary.
Using KLF11 as a representative model for mechanistic studies, we demonstrate that this protein inhibits the ability of cancer cells to form both colonies in soft agar and tumour growth in vivo.
Among the genes revealing changes, interesting targets were identified: ie demethylation of KLF11, a putative tumour suppressor gene, and hypermethylation of CFLAR, a gene previously described in treatment resistance in GCTs.
Together, these results suggest a central role for KLF11 in TGFbeta-induced c-myc repression and antiproliferation and identifies a novel mechanism through which ERK signaling antagonizes the tumor suppressor activities of TGFbeta in pancreatic cancer cells with oncogenic Ras mutations.