When RON MET TAM in Mesothelioma: All Druggable for One, and One Drug for All?
Malignant pleural mesothelioma (MPM) is an aggressive inflammatory cancer with a poor survival rate. Treatment options are limited at best and drug resistance is common. Thus, there is an urgent need to identify novel therapeutic targets in this disease in order to improve patient outcomes and survival times. MST1R (RON) is a trans-membrane receptor tyrosine kinase (RTK), which is part of the c-MET proto-oncogene family. The only ligand recognized to bind MST1R (RON) is Macrophage Stimulating 1 (MST1), also known as Macrophage Stimulating Protein (MSP) or Hepatocyte Growth Factor-Like Protein (HGFL). In this study, we demonstrate that the MST1-MST1R (RON) signaling axis is active in MPM. Targeting this pathway with a small molecule inhibitor, LCRF-0004, resulted in decreased proliferation with a concomitant increase in apoptosis. Cell cycle progression was also affected. Recombinant MST1 treatment was unable to overcome the effect of LCRF-0004 in terms of either proliferation or apoptosis. Subsequently, the effect of an additional small molecular inhibitor, BMS-777607 (which targets MST1R (RON), MET, Tyro3, and Axl) also resulted in a decreased proliferative capacity of MPM cells. In a cohort of MPM patient samples, high positivity for total MST1R by IHC was an independent predictor of favorable prognosis. Additionally, elevated expression levels of MST1 also correlated with better survival. This study also determined the efficacy of LCRF-0004 and BMS-777607 in xenograft MPM models. Both LCRF-0004 and BMS-777607 demonstrated significant anti-tumor efficacy
Health Research Board (HRB) Ireland grants HRA_POR/2010/19, HRA_POR/2013/237 (SG and A-MB), Buzzi Unicem Foundation for Mesothelioma Research—Grant P24 (SG), NCI/NIH 2U01CA 111295-04 (HP) and a Senior Clinical Research Fellow (SCRF) award Queensland Government, Office of Health, and Medical Research.
CommentsThe original article is available at www.frontiersin.org
Published CitationBaird AM, Easty D, Jarzabek M, Shiels L, Soltermann A, Klebe S, Raeppel S, MacDonagh L, Wu C, Griggs K, Kirschner MB, Stanfill B, Nonaka D, Goparaju CM, Murer B, Fennell DA, O'Donnell DM, Barr MP, Mutti L, Reid G, Finn S, Cuffe S, Pass HI, Opitz I, Byrne AT, O'Byrne KJ, Gray SG. When RON MET TAM in Mesothelioma: All Druggable for One, and One Drug for All? Frontiers in Endocrinology. 2019;10:89.
- Centre for Systems Medicine
- Physiology and Medical Physics