Pyruvate kinase, muscle type 2 (PKM2), is a key factor in the aerobic glycolysis of cancer cells. In our experiments,
liver cancer cell lines exhibited a range of sensitivity to PKM2 knockdown-mediated growth inhibition. We speculated
that this differential sensitivity is attributable to the variable dependency on glycolysis for the growth of different
cell lines. Transcriptome data revealed overexpression of a glucose transporter (GLUT3) and a lactate transporter
(MCT4) genes in PKM2 knockdown-sensitive cells. PKM2 knockdown-resistant cells expressed high levels of the
lactate dehydrogenase B (LDHB) and glycine decarboxylase (GLDC) genes. Concordant with the gene expression
results, PKM2 knockdown-sensitive cells generated high levels of lactate. In addition, ATP production was significantly
reduced in the PKM2 knockdown-sensitive cells treated with a glucose analog, indicative of dependency of
their cellular energetics on lactate-producing glycolysis. The PKM2 knockdown-resistant cells were further subdivided
into less glycolytic and more (glycolysis branch pathway-dependent) glycolytic groups. Our findings collectively
support the utility of PKM2 as a therapeutic target for high lactate-producing glycolytic hepatocellular carcinoma
(HCC).

Keywords: glycolysis, glycolysis-dependent, lactate, PKM2, SLC16A3