Comorbidity between lung cancer and COVID-19 pneumonia: role of immunoregulatory gene transcripts in high -expressing normal lung.

Background: SARS-CoV-2 (COVID-19) elicits a T-cell antigen-mediated immune response of variable efficacy. To understand this variability, we explored transcriptomic expression of angiotensin-converting enzyme 2 (, the SARS-CoV-2 receptor) and of immunoregulatory genes in normal lung tissues from patients with non-small cell lung cancer (NSCLC).

Methods: This study used the transcriptomic and the clinical data for NSCLC patients generated during the CHEMORES study [ = 123 primary resected (early-stage) NSCLC] and the WINTHER clinical trial ( = 32 metastatic NSCLC).

Results: We identified patient subgroups with high and low expression ( = 1.55 × 10) in normal lung tissue, presumed to be at higher and lower risk, respectively, of developing severe COVID-19 should they become infected. transcript expression in normal lung tissues (but not in tumor tissue) of patients with NSCLC was higher in individuals with more advanced disease. High- expressors had significantly higher levels of CD8+ cytotoxic T lymphocytes and natural killer cells but with presumably impaired function by high Thymocyte Selection-Associated High Mobility Group Box Protein TOX () expression. In addition, immune checkpoint-related molecules - , and are more highly expressed in normal (but not tumor) lung tissues; these molecules might dampen immune response to either viruses or cancer. Importantly, however, high inducible T-cell co-stimulator (), which can amplify immune and cytokine reactivity, significantly correlated with high expression in univariable analysis of normal lung (but not lung tumor tissue).

Conclusions: We report a normal lung immune-tolerant state that may explain a potential comorbidity risk between two diseases - NSCLC and susceptibility to COVID-19 pneumonia. Further, a NSCLC patient subgroup has normal lung tissue expressing high and high transcripts, the latter potentially promoting a hyperimmune response, and possibly leading to severe COVID-19 pulmonary compromise.