Abstract
The M2 pyruvate kinase (PKM2) isoform is upregulated in most cancers and plays a crucial role in the Warburg effect, which is characterized by the preference for aerobic glycolysis for energy metabolism. PKM2 is an alternative-splice isoform of the PKM gene, and is a potential therapeutic target. Previously, we developed antisense oligonucleotides (ASOs) that switch PKM splicing from the cancer-associated PKM2 to the PKM1 isoform and induce apoptosis in cultured glioblastoma cells. Here, we explore the potential of ASO-based PKM splice-switching as a targeted therapy for liver cancer. We utilize a lead cEt/DNA ASO, which has a higher potency than MOE modification, to demonstrate that it induces PKM splice-switching and inhibits the growth of cultured hepatocellular-carcinoma (HCC) cells. This PKM isoform switch increases pyruvate-kinase activity and alters glucose metabolism. The lead ASO inhibits tumorigenesis in an orthotopic-xenograft HCC mouse model. Finally, a surrogate mouse-specific ASO induces Pkm splice-switching and inhibits HCC growth, without observable toxicity, in a genetic HCC mouse model.
Statement of significance Antisense oligonucleotides are used to force a change in PKM isoform usage in HCC, reversing the Warburg effect and inhibiting tumorigenesis.
Competing Interest Statement
F.R. and C.F.B. are employees of Ionis Pharmaceuticals and own stock options. F.R., C.F.B., and A.R.K. are inventors on patent applications covering the use of PKM ASOs.
