Cristina Chiriaco1,2, Chiara Donini1,3, Valeria Leuci1, Elisa Vigna4,5, Marco Cortese1,3, Stefano Ughetto1,3,6, Chiara Modica1,7, Ilaria Martinelli1, Alessia Proment1,3, Letizia Vitali1,3, Lara Fontani1, Monica Casucci8, Paolo Maria Comoglio9, Silvia Giordano1,3, Dario Sangiolo1,3. 1. Candiolo Cancer Institute, FPO-IRCCS, Strada Provinciale 142, 10060, Candiolo, TO, Italy. 2. , Present address: Anemocyte S.r.l., 21040, Gerenzano, VA, Italy. 3. Department of Oncology, University of Turin, Turin, Italy. 4. Candiolo Cancer Institute, FPO-IRCCS, Strada Provinciale 142, 10060, Candiolo, TO, Italy. e.vigna@unito.it. 5. Department of Oncology, University of Turin, Turin, Italy. e.vigna@unito.it. 6. Present address: Bios-Therapy, Physiological System for Health S.p.A, 52037, Sansepolcro, AR, Italy. 7. Present address: Department of Surgical, Oncological and Stomatological Sciences (DICHIRONS), University of Palermo, 90127, Palermo, Italy. 8. Innovative Immunotherapies Unit, IRCCS San Raffaele Scientific Institute, Milan, Italy. 9. IFOM-FIRC Institute of Molecular Oncology, Milan, Italy.
Abstract
BACKGROUND: Aberrant activation of the MET receptor in cancer is sustained by genetic alterations or, more frequently, by transcriptional upregulations. A fraction of MET-amplified or mutated tumors are sensible to MET targeting agents, but their responsiveness is typically short-lasting, as secondary resistance eventually occurs. Since in the absence of genetic alterations MET is usually not a tumor driver, MET overexpressing tumors are not/poorly responsive to MET targeted therapies. Consequently, the vast majority of tumors exhibiting MET activation still represent an unmet medical need. METHODS: Here we propose an immunotherapy strategy based on T lymphocytes expressing a Chimeric Antigen Receptor (CAR) targeting MET overexpressing tumors of different histotypes. We engineered two different MET-CAR constructs and tested MET-CAR-T cell cytotoxic activity against different MET overexpressing models, including tumor cell lines, primary cancer cells, organoids, and xenografts in immune-deficient mice. RESULTS: We proved that MET-CAR-T exerted a specific cytotoxic activity against MET expressing cells. Cell killing was proportional to the level of MET expressed on the cell surface. While CAR-T cytotoxicity was minimal versus cells carrying MET at physiological levels, essentially sparing normal cells, the activity versus MET overexpressing tumors was robust, significantly controlling tumor cell growth in vitro and in vivo. Notably, MET-CAR-T cells were also able to brake acquired resistance to MET targeting agents in MET amplified cancer cells carrying secondary mutations in downstream signal transducers. CONCLUSIONS: We set and validated at the pre-clinical level a MET-CAR immunotherapy strategy potentially beneficial for cancers not eligible for MET targeted therapy with inhibitory molecules, including those exhibiting primary or secondary resistance.
BACKGROUND: Aberrant activation of the MET receptor in cancer is sustained by genetic alterations or, more frequently, by transcriptional upregulations. A fraction of MET-amplified or mutated tumors are sensible to MET targeting agents, but their responsiveness is typically short-lasting, as secondary resistance eventually occurs. Since in the absence of genetic alterations MET is usually not a tumor driver, MET overexpressing tumors are not/poorly responsive to MET targeted therapies. Consequently, the vast majority of tumors exhibiting MET activation still represent an unmet medical need. METHODS: Here we propose an immunotherapy strategy based on T lymphocytes expressing a Chimeric Antigen Receptor (CAR) targeting MET overexpressing tumors of different histotypes. We engineered two different MET-CAR constructs and tested MET-CAR-T cell cytotoxic activity against different MET overexpressing models, including tumor cell lines, primary cancer cells, organoids, and xenografts in immune-deficient mice. RESULTS: We proved that MET-CAR-T exerted a specific cytotoxic activity against MET expressing cells. Cell killing was proportional to the level of MET expressed on the cell surface. While CAR-T cytotoxicity was minimal versus cells carrying MET at physiological levels, essentially sparing normal cells, the activity versus MET overexpressing tumors was robust, significantly controlling tumor cell growth in vitro and in vivo. Notably, MET-CAR-T cells were also able to brake acquired resistance to MET targeting agents in MET amplified cancer cells carrying secondary mutations in downstream signal transducers. CONCLUSIONS: We set and validated at the pre-clinical level a MET-CAR immunotherapy strategy potentially beneficial for cancers not eligible for MET targeted therapy with inhibitory molecules, including those exhibiting primary or secondary resistance.
Authors: Sai-Hong Ignatius Ou; Eunice L Kwak; Christina Siwak-Tapp; Joni Dy; Kristin Bergethon; Jeffrey W Clark; D Ross Camidge; Benjamin J Solomon; Robert G Maki; Yung-Jue Bang; Dong-Wan Kim; James Christensen; Weiwei Tan; Keith D Wilner; Ravi Salgia; A John Iafrate Journal: J Thorac Oncol Date: 2011-05 Impact factor: 15.609
Authors: Jochen K Lennerz; Eunice L Kwak; Allison Ackerman; Michael Michael; Stephen B Fox; Kristin Bergethon; Gregory Y Lauwers; James G Christensen; Keith D Wilner; Daniel A Haber; Ravi Salgia; Yung-Jue Bang; Jeffrey W Clark; Benjamin J Solomon; A John Iafrate Journal: J Clin Oncol Date: 2011-10-31 Impact factor: 44.544