Abstract A84: Regulation of 6-phosphofructo-2-kinase (PFKFB3) by estradiol and implications for the treatment of ER+ metastatic breast cancer

Estradiol (E2) administered to estrogen receptor positive (ER+) breast cancer patients stimulates glucose uptake by tumors. This E2-induced metabolic flare is predictive of the clinical effectiveness of anti-estrogens and downstream metabolic regulators of E2 are expected to have utility as targets for the development of anti-breast cancer agents. While the stimulation of glucose metabolism by E2 has been demonstrated, relatively little is known about the precise downstream effectors required for E2 to stimulate glucose metabolism in breast cancer. The family of 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatases (PFKFB1-4) control glycolytic flux via their product, fructose-2,6-bisphosphate (F26BP), which activates 6-phosphofructo-1-kinase (PFK-1). We recently demonstrated that PFKFB3 expression is elevated in breast cancer lymph node metastases and that exposure of human MCF-7 and T-47D breast cancer cells to E2 causes a rapid increase in 14C-glucose uptake and glycolysis that is coincident with an induction of PFKFB3 mRNA (via ER binding to its promoter), protein expression and the intracellular concentration of its product, F26BP. Importantly, we also found that selective inhibition of PFKFB3 expression and activity using siRNA or a PFKFB3 inhibitor, PFK158, markedly reduces the E2-mediated increase in F26BP, 14C-glucose uptake and glycolysis. In the current study, we sought to determine if co-administration of PFK158, with ICI 182,780 (fulvestrant), would offer a great...
Source: Molecular Cancer Research - Category: Cancer & Oncology Authors: Tags: Therapeutic Targets From Cancer: Poster Presentations - Proffered Abstracts Source Type: research