Fig. 4.

Elevated nuclear YAP levels are observed in precancerous human airways. (A) Endobronchial patient biopsies exhibiting the noted pathologies were examined by IF microscopy for YAP, KRT5, and CRB3, which revealed a loss of apical CRB3 organization, along with elevated nuclear YAP in KRT5-positive precancerous and carcinoma lesions. Representative images are shown from tissues exhibiting normal (n = 6), metaplasia (n = 7), dysplasia (n = 8), and CIS (n = 2) pathology. (Scale bar, 5 μm.) (B) Quantification of nuclear YAP levels in the noted airway pathologies demonstrated an increase in nuclear YAP levels that is associated with precancerous metaplasia, dysplasia, and CIS pathology. Shown in the average nuclear YAP intensity ± SEM quantified from 11 images across 6 patient tissues with normal pathology, 11 images across 7 patients with metaplastic pathology, 12 images across 8 patients with metaplastic pathology, and 15 images across 2 patients with CIS pathology. Significance was determined with a Tukey’s multiple comparisons test. *P < 0.05, **P < 0.01, and ****P < 0.0001.