INVESTIGATION OF THE ROLE OF 6-PHOSPHOFRUCTO-2-KINASE/FRUCTOSE-2,6-BISPHOSPHOTASE-3 (PFKFB3) ON KRAS ASSOSICIATED ONCOGENIC TRANSFORMATION

Cancer cells have increased glycolysis in the presence of oxygen and this phenomenon is called 'Warbug effect'. Bifunctional 6-phospho-2kinase/fructose-2,6-bisphotase (PFKFB) protein family is highly considerable in glycoliyses regulation. In this protein family, PFKFB3 has the highest kinase activity and it is expressed most of the malignancies including pancreatic ductal adenocarcinoma. Ras proteins regulate signal transduction underlying cellular activities. Various types of cancers has Kras mutation. Moreover, increased glycolysis and cell proliferation is associated with Kras mutation. Pancreatic ductal adenocarcinoma is one of the most lethal type of solid malignancies and %90 of cases have Kras mutation. The purpose of this study; investigation of effect of Kras mutation on PFKFB3 and PFKFB3 effect of Kras associated oncogenic transformation. We found that PFKFB3 expression is increased in Kras mutated cells. Silencing of PFKFB3 caused reduced glucose uptake (glucose levels in medium; IPDE siCtrl: 127 µmol/mg, IPDE siP3/2: 176,35 µmol/mg, KPDE siCtrl: 83 µmol/mg, KPDE siP3/2: 97,74 µmol/mg), lactate production (lactic acid levels in medium; IPDE siCtrl: 38,16 µmol/mg, IPDE siP3/2: 24,40 µmol/mg, KPDE siCtrl: 48 µmol/mg, KPDE siP3/2: 29,29 µmol/mg) and increased cell mortality (cell numbers after 48 hours of transfection; IPDE siCtrl: 520 + 14x103, IPDE siP3/2: 605 + 70x103, KPDE siCtrl: 673,3 + 20x103, KPDE siP3/2: 550 + 20x103). Also, silencing of PFKFB3 decreased invasion but didn't effect the colony formation capasity in soft agar. Furthermore, we found that PFK158 doesn't effect the susceptibility of Gemcitabine. In conclusion, we showed that glycolysis may be regulated by PFKFB3 in Kras mutated cells. Furthermore, PFKFB3 may have role in cell sustainability and invasion in these cells.