ESRRB and cancer: NR4A2, also known as Nurr1, is an orphan nuclear receptor involved in immunology, neurodegenerative pathology, and cancer.[35, 36, 37, 38] NR4A2 is significantly activated during the differentiation of human type II pneumocytes, the major targets of SARS‐CoV‐2.[13, 39] The expression of NR4A2 positively correlates with aging in human lung tissue expression datasets, and older mice exhibit higher Nr4a2 expression than younger mice.