Epigenetic regulation of RTK signalling in acute myeloid leukaemia
Lead Research Organisation:
Queen Mary University of London
Department Name: Barts Cancer Institute
Abstract
Receptor tyrosine kinases (RTKs) and their associated intracellular signalling pathways act in response to growth factors and other extracellular cues to regulate fundamental biological processes, such as metabolism, cell growth, cell proliferation and survival. Dysregulation of said pathways is common in a variety of human diseases, most notably diabetes, neurodegeneration and cancer. Hence, effectors of RTK signalling have historically been the preferred targets for drug discovery, particularly in the field of metabolic syndrome and cancer research. In addition, members of the RTK network, such as mTORC1, have been found to play a role in physiological ageing in mammals. The status of the signalling network and its circuitry seem to determine the responses of cells to inhibitor treatment. However, the mechanisms by which cells wire their signalling network are not well understood.
The aim of this project is to investigate how non-inheritable modifications, such as epigenetic changes, determine the circuitry of signalling networks downstream of RTKs. Potential for treatments targeting epigenetic effectors has been demonstrated by drugs such as Vorinostat, a histone deacetylase inhibitor, going through clinical trials for the treatment of leukaemia and lymphoma in combination with other chemotherapeutic drugs, and by the histone methyltransferase EZH2 emerging as a potential target for treatment in the past few years. In this project, a series of epigenetic drugs will be tested in combination with kinase inhibitors in a variety of acute myeloid leukaemia (AML) cell lines. Cell proliferation and viability assays will be performed to test the efficacy of the combinatorial treatments. The effect of the drugs at the molecular level will then be evaluated using mass spectrometry-based proteomics and phosphoproteomics analyses, looking at both epigenetic changes (particularly with regard to histone modifications) and instances of kinase signalling rewiring.
We expect this project will uncover how epigenetic changes at the level of chromatin modification impact the structure and topology of signalling networks. In addition to increasing our understanding of cell signalling, these research outputs may also inform drug treatment aimed at devising more effective therapeutic strategies in the future.
The aim of this project is to investigate how non-inheritable modifications, such as epigenetic changes, determine the circuitry of signalling networks downstream of RTKs. Potential for treatments targeting epigenetic effectors has been demonstrated by drugs such as Vorinostat, a histone deacetylase inhibitor, going through clinical trials for the treatment of leukaemia and lymphoma in combination with other chemotherapeutic drugs, and by the histone methyltransferase EZH2 emerging as a potential target for treatment in the past few years. In this project, a series of epigenetic drugs will be tested in combination with kinase inhibitors in a variety of acute myeloid leukaemia (AML) cell lines. Cell proliferation and viability assays will be performed to test the efficacy of the combinatorial treatments. The effect of the drugs at the molecular level will then be evaluated using mass spectrometry-based proteomics and phosphoproteomics analyses, looking at both epigenetic changes (particularly with regard to histone modifications) and instances of kinase signalling rewiring.
We expect this project will uncover how epigenetic changes at the level of chromatin modification impact the structure and topology of signalling networks. In addition to increasing our understanding of cell signalling, these research outputs may also inform drug treatment aimed at devising more effective therapeutic strategies in the future.
Studentship Projects
| Project Reference | Relationship | Related To | Start | End | Student Name |
|---|---|---|---|---|---|
| BB/M009513/1 | 01/10/2015 | 31/03/2024 | |||
| 1763856 | Studentship | BB/M009513/1 | 01/10/2016 | 30/03/2021 | Salvatore Pedicona |
| Description | As a result of the work funded through this award, we found that: - Mass spectrometry-based proteomics and phosphoproteomics methods can be effectively used to investigate cell signalling rewiring in response to treatment with epigenetic drugs. - Treatment with epigenetic drugs leads to significant changes in intracellular signalling pathways. In particular, inhibition of the histone demethylase LSD1 has been found to be particularly effective in driving cell signalling rewiring in leukaemia cells. - Cell signalling rewiring resulting from LSD1 inhibition sensitises leukaemia cells to subsequent treatment with kinase inhibitors (when their effect on cell proliferation and viability is taken into account). 5 days pre-treatment with the LSD1 inhibitor, followed by a 3-day treatment with a kinase inhibitor has been found to be the optimal regimen. This sensitising effect of LSD1 inhibition has been observed in a variety of acute myeloid leukaemia (AML) cell lines. - The effect of LSD1 inhibition on intracellular signalling was found to be cell line dependent. Overall, the activities of kinases involved in cell cycle regulation, DNA replication, gene expression, protein translation and metabolism were found to be affected in all cell lines tested, consistent with the general effect of LSD1 inhibition in driving down cell proliferation. Other notable effects were limited to specific cell lines. For example, in HEL cells treatment with LSD1 inhibitor leads to a down regulation of MEK signalling and to an upregulation of AKT signalling; this is consistent with the sensitisation of HEL cells to PI3K inhibition by LSD1 inhibitor treatment. In P31/Fuj, LSD1 inhibition was found to lead to an upregulation of protein levels of components of the RAS/MEK/ERK signalling pathway, while leading to a downregulation of components of the PI3K/AKT signalling pathway. This is consistent with the strong sensitisation of these cells to MEK inhibition carried out by pre-treatment with LSD1 inhibitor. - Preliminary tests of the sequential treatment with LSD1 inhibitor and kinase inhibitors on primary cells have shown that normal haematopoietic cells are not particularly affected by the treatment (i.e. limited potential toxicity). The sequential treatment with LSD1 inhibitor, followed by MEK inhibitor, has been found to be particularly effective at reducing proliferation and viability in a majority of the patient-derived primary AML cells tested in a synergistic manner. The patient subgroups that were best responsive to this particular treatment were also identified: these were samples carrying a KRAS mutation, or with an MLL karyotype, or belonging to the M5 FAB classification group. |
| Exploitation Route | In the future, the use of an LSD1 inhibitor with a kinase inhibitor in combination could be tested in animal models and successive clinical trials to assess their efficacy in a more physiological setting. |
| Sectors | Healthcare,Pharmaceuticals and Medical Biotechnology |