In our current work, an intriguing finding that FOSB expression indicated diametrically opposed prognoses between the two most common histological subtypes of NSCLC, lung adenocarcinoma (LUAD) and lung squamous cell carcinoma (LUSC), provided critical scientific clues for us to narrate this story that unraveled the mystery of its “two sides” in NSCLC (Fig. 1). This evidence concerns the gene FOSB and lung adenocarcinoma.