Hunter Cancer Research Alliance
As a multidisciplinary and multi-institutional alliance, the Hunter Cancer Research Alliance (HCRA) functions to provide capacity building, funding and strategic support to cancer research across the translational research continuum – from basic research through clinical trials to behavioural, implementation and health services research.
With the support of our partnering institutions, executive leaders and a membership that consists of 250+ cancer-focused researchers, we are working to promote the excellence of cancer research in the Hunter and ultimately improve cancer patient outcomes in our region and beyond.
HCRA Director, Professor Stephen Ackland, explains the work of HCRA in the video below:
Activation of protein phosphatase 2A in FLT3+ acute myeloid leukamia cells enhances the cytotoxicity of FLT3 tyrosine kinase inhibitors
Amanda M Smith, Matthew D Dunn, Erwin M Lee, Celeste Harrison, Richard Kahl, Hayley Flanagan, Nikita Panicker, Bratali Mashkani, Anthony S Don, Jonathan Morris, Hamish Toop, Richard B Lock, Jason A Powell, Daniel Thomas, Mark A Guthridge, Andrew Moore, Leonie K Ashman, Kathryn A Skelding, Anoop Enjeti, Nicole M Verrills.
Constitutive activation of the receptor tyrosine kinase Fms-like tyrosine kinase 3 (FLT3), via co-expression of its ligand or by genetic mutation, is common in acute myeloid leukemia (AML). In this study we show that FLT3 activation inhibits the activity of the tumor suppressor, protein phosphatase 2A (PP2A). Using BaF3 cells transduced with wildtype or mutant FLT3, we show that FLT3-induced PP2A inhibition sensitizes cells to the pharmacological PP2A activators, FTY720 and AAL(S). FTY720 and AAL(S) induced cell death and inhibited colony formation of FLT3 activated cells. Furthermore, PP2A activators reduced the phosphorylation of ERK and AKT, downstream targets shared by both FLT3 and PP2A, in FLT3/ITD+ BaF3 and MV4-11 cell lines. PP2A activity was lower in primary human bone marrow derived AML blasts compared to normal bone marrow, with blasts from FLT3-ITD patients displaying lower PP2A activity than WT-FLT3 blasts. Reduced PP2A activity was associated with hyperphosphorylation of the PP2A catalytic subunit, and reduced expression of PP2A structural and regulatory subunits. AML patient blasts were also sensitive to cell death induced by FTY720 and AAL(S), but these compounds had minimal effect on normal CD34+ bone marrow derived monocytes. Finally, PP2A activating compounds displayed synergistic effects when used in combination with tyrosine kinase inhibitors in FLT3/ITD+ cells. A combination of Sorafenib and FTY720 was also synergistic in the presence of a protective stromal microenvironment. Thus combining a PP2A activating compound and a FLT3 inhibitor may be a novel therapeutic approach for treating AML.
May: Twyman, L. et al (2016) Electronic Cigarettes: Awareness, Recent Use, and Attitudes within a sample of Socioeconomically disadvantaged Australian Smokers. Nicotine & Tocacco Research 18(5):670-677