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Continuous carcinogen exposure through smoking creates a field of injury along the airway and resulting in mutations which promote remodeling of the bronchial epithelium. Over time lesions can form and exhibit increasing abnormalities progressing from goblet cell hyperplasia (GCH) which is the earliest detectable premalignant state through hyperplasia and squamous metaplasia to incremental stages of dysplasia, carcinoma in situ (CIS) and eventually to frank carcinoma. Unfortunately, more than half of all lung cancer patients are diagnosed with metastatic disease with a dismal 5-year survival rate of only 5.2%. However, when diagnosed at an early stage, the 5-year survival rate is more than 10 times as high. Our group has identified NOTCH1 as the most frequently mutated gene in progressive lung premalignant lesions (PMLs). However, these mutations are significantly less common in advanced lung squamous cell carcinoma (LUSC), indicating a role for NOTCH1 in the pre-tumorigenic environment rather than contributing to the actual tumor mass. Transcriptomic profiling of NOTCH1 mutated lesions identified up regulation of peri-goblet cells (PGC), a newly identified bronchial epithelial cell type that is associated with smoking, and a down regulation of immune components. Using highly multiplex Imaging Mass Cytometry (IMC) to analyze the epithelium of NOTCH1 mutated PMLs and its interplay with the immune system in situ. We identified a shift in epithelial composition with an increase in un- and de-differentiated cells. Interestingly, PGC appear to be an intermediate cell type on a previously undescribed path to goblet cell differentiation. In a parallel approach we are modeling NOTCH1 driven dysplasia in vitro to gain insight into the molecular mechanisms of lesion progression. Primary human bronchial epithelial cells (hBECs) grown at the air-liquid interface (ALI) into mature epithelia are exposed to cigarette smoke condensate (CSC) or IL-13 to model the early stages of bronchial airway dysplasia. Continuous exposure of these differentiating cultures to either stimulus increases the abundance of goblet cells and PGCs in a dose dependent manner with IL-13 additionally leading to the loss of baso-apical organization of the epithelium. After successfully modeling the first stage of bronchial epithelial dysplasia we are now advancing our model by co-culturing primary hBECs with NOTCH1 mutated cells and to disentangle the pathway of basal-PGC-goblet cell differentiation. Understanding driving forces in early lesion progression will further our ability to discern progressive lesions from those that regress naturally and facilitate interventions that force lesions into regression. Citation Format: Roxana Michaela Pfefferkorn, Darren Jianjhih Chiu, Divya Lakshmi Venkatraman, Jennifer Ellen Beane, Sarah Anne Mazzilli, Joshua David Campbell. The role of NOTCH1 in bronchial pre-malignant lesions. [abstract]. In: Proceedings of the AACR Special Conference: Precision Prevention, Early Detection, and Interception of Cancer; 2022 Nov 17-19; Austin, TX. Philadelphia (PA): AACR; Can Prev Res 2023;16(1 Suppl): Abstract nr PR004. |
