Fig. 4.

Attenuated pyruvate dehydrogenase (PDH) activity and mitochondrial reserve capacity in glioblastoma are mediated through downregulation of pyruvate dehydrogenase phosphatase (PDP) expression. (A) The PDH regulatory proteins PDP1-2 and PDK1-4 were evaluated by reverse transcriptase PCR in the described cell lines and treatment conditions. Levels were quantified relative to actin and then normalized to the T cell line. (B) Western blot was performed to determine levels of PDP1 expression in TR cells treated in the described conditions. (C) Western blot was performed to determine levels of the stated proteins in T, TR, and the TR line overexpressing PDP1 (TR + PDP1). (D) The respiratory phenotype of the described cell lines was determined using the Seahorse platform. (E) PDP1 expression in normal brain and GBM was evaluated on the The Cancer Genome Atlas platform. *P < .01.