HMGB1 Expression Levels Correlate with Response to Immunotherapy in Non-Small Cell Lung Cancer

Maria González-Cao,1 Xueting Cai,2 Jilian Wilhelmina Paulina Bracht,3 Xuan Han,2 Yang Yang,2 Carlos Pedraz-Valdunciel,4 Teresa Morán,5 Javier García-Corbacho,6 Andrés Aguilar,1 Reyes Bernabé,7 Pedro De Marchi,8,9 Luciane Sussuchi da Silva,8 Leticia Ferro Leal,8 Rui Manuel Reis,8,10,11 Jordi Codony-Servat,4 Eloisa Jantus-Lewintre,12– 14 Miguel Angel Molina-Vila,4 Peng Cao,2,15 Rafael Rosell1,16 1Translational Cancer Research Unit, Instituto Oncológico Dr Rosell, Dexeus University Hospital, Barcelona, Spain; 2Integrated Traditional Chinese and Western Medicine Department of Affiliated Hospital, Nanjing University of Chinese Medicine, Nanjing, Jiangsu, People’s Republic of China; 3Amsterdam University Medical Center (UMC), Amsterdam, The Netherlands; 4Laboratory of Oncology, Pangaea Oncology, Quirón Dexeus University Hospital, Barcelona, Spain; 5Medical Oncology Department, Catalan Institute of Oncology (ICO), Germans Trias i Pujol Hospital, Badalona, Spain; 6Medical Oncology Department (Hospital Clinic)/Translational Genomics and Targeted Therapies in Solid Tumors (IDIBAPs), Barcelona, Spain; 7Medical Oncology Department, Hospital Universitario Virgen del Rocío, Sevilla, Spain; 8Molecular Oncology Research Center; Barretos Cancer Hospital, Barretos, Brazil; 9Oncoclinicas, Rio de Janeiro, Brazil; 10Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Braga, Portugal; 11ICVS/3b’s – PT Government Associate Laboratory, Braga/Guimarães, Portugal; 12Valencian Community Foundation Principe Felipe Research Center, Laboratory of Molecular Oncology, Valencia, Spain; 13Centro de Investigación Biomédica en Red (CIBERONC), Madrid, Spain; 14Universitat Politècnica de Valencia, Biotechnology Department, Valencia, Spain; 15College of Pharmacy, Nanjing University of Chinese Medicine, Nanjing, Jiangsu, People’s Republic of China; 16Laboratory of Molecular Biology, Germans Trias i Pujol Health Sciences Institute and Hospital (IGTP), Badalona, SpainCorrespondence: Rafael Rosell, Laboratory of Molecular Biology, Germans Trias i Pujol Health Sciences Institute and Hospital (IGTP), Camí de les Escoless/n, Badalona, Barcelona, 08916, Spain, Tel +34 930330520, Email rrosell@iconcologia.net Peng Cao, College of Pharmacy, Nanjing University of Chinese Medicine, Nanjing, 210023, People’s Republic of China, Tel +86 85608666, Email cao_peng@njucm.edu.cnPurpose: High-mobility group box 1 protein (HMGB1) is subject to exportin 1 (XPO1)-dependent nuclear export, and it is involved in functions implicated in resistance to immunotherapy. We investigated whether HMGB1 mRNA expression was associated with response to immune checkpoint inhibitors (ICI) in non-small cell lung cancer (NSCLC).Patients and Methods: RNA was isolated from pretreatment biopsies of patients with advanced NSCLC treated with ICI. Gene expression analysis of several genes, including HMGB1, was conducted using the NanoString Counter analysis system (PanCancer Immune Profiling Panel). Western blotting analysis and cell viability assays in EGFR and KRAS mutant cell lines were carried out. Evaluation of the antitumoral effect of ICI in combination with XPO1 blocker (selinexor) and trametinib was determined in a murine Lewis lung carcinoma model.Results: HMGB1 mRNA levels in NSCLC patients treated with ICI correlated with progression-free survival (PFS) (median PFS 9.0 versus 18.0 months, P=0.008, hazard ratio=0.30 in high versus low HMGB1). After TNF-α stimulation, HMGB1 accumulates in the cytoplasm of PC9 cells, but this accumulation can be prevented by using selinexor or antiretroviral drugs. Erlotinib or osimertinib with selinexor in EGFR-mutant cells and trametinib plus selinexor in KRAS mutant abolish tumor cell proliferation. Selinexor with a PD-1 inhibitor with or without trametinib abrogates the tumor growth in the murine Lewis lung cancer model.Conclusion: An in-depth exploration of the functions of HMGB1 mRNA and protein is expected to uncover new potential targets and provide a basis for treating metastatic NSCLC in combination with ICI.Keywords: HMGB1, immunotherapy, non-small cell lung cancer, Lewis lung cancer murine model, K-Ras mutations