Localized and chronic hypoxia of airway mucosa is a common feature of progressive respiratory diseases, including cystic fibrosis (CF). However, the impact of prolonged hypoxia on airway stem cell function and differentiated epithelium is not well elucidated. Acute hypoxia alters the transcription and translation of many genes, including the CF transmembrane conductance regulator (CFTR). CFTR-targeted therapies (modulators) have not been investigated in vitro under chronic hypoxic conditions found in CF airways in vivo. Nasal epithelial cells (hNECs) derived from eight CF and three non-CF participants were expanded and differentiated at the air–liquid interface (26–30 days) at ambient and 2% oxygen tension (hypoxia). Morphology, global proteomics (LC-MS/MS) and function (barrier integrity, cilia motility and ion transport) of basal stem cells and differentiated cultures were assessed. hNECs expanded at chronic hypoxia, demonstrating epithelial cobblestone morphology and a similar proliferation rate to hNECs expanded at normoxia. Hypoxia-inducible proteins and pathways in stem cells and differentiated cultures were identified. Despite the stem cells’ plasticity and adaptation to chronic hypoxia, the differentiated epithelium was significantly thinner with reduced barrier integrity. Stem cell lineage commitment shifted to a more secretory epithelial phenotype. Motile cilia abundance, length, beat frequency and coordination were significantly negatively modulated. Chronic hypoxia reduces the activity of epithelial sodium and CFTR ion channels. CFTR modulator drug response was diminished. Our findings shed light on the molecular pathophysiology of hypoxia and its implications in CF. Targeting hypoxia can be a strategy to augment mucosal function and may provide a means to enhance the efficacy of CFTR modulators.

CF-related diabetes (CFRD) is a prevalent comorbidity in people with Cystic Fibrosis (CF), significantly impacting morbidity and mortality rates. This review article critically evaluates the current understanding of CFRD molecular mechanisms, including the role of CFTR protein, oxidative stress, unfolded protein response (UPR) and intracellular communication. CFRD manifests from a complex interplay between exocrine pancreatic damage and intrinsic endocrine dysfunction, further complicated by the deleterious effects of misfolded CFTR protein on insulin secretion and action. Studies indicate that ER stress and subsequent UPR activation play critical roles in both exocrine and endocrine pancreatic cell dysfunction, contributing to β-cell loss and insulin insufficiency. Additionally, oxidative stress and altered calcium flux, exacerbated by CFTR dysfunction, impair β-cell survival and function, highlighting the significance of antioxidant pathways in CFRD pathogenesis. Emerging evidence underscores the importance of exosomal microRNAs (miRNAs) in mediating inflammatory and stress responses, offering novel insights into CFRD's molecular landscape. Despite insulin therapy remaining the cornerstone of CFRD management, the variability in response to CFTR modulators underscores the need for personalized treatment approaches. The review advocates for further research into non-CFTR therapeutic targets, emphasizing the need to address the multifaceted pathophysiology of CFRD. Understanding the intricate mechanisms underlying CFRD will pave the way for innovative treatments, moving beyond insulin therapy to target the disease's root causes and improve the quality of life for individuals with CF.

Cancer cell mitochondria are functionally different from those in normal cells and could be targeted to develop novel anticancer agents. The aryl-ureido fatty acid CTU (16({[4-chloro-3-(trifluoromethyl)phenyl]-carbamoyl}amino)hexadecanoic acid) is the prototype of a new class of targeted agents that enhance the production of reactive oxygen species (ROS) that disrupt the outer mitochondrial membrane (OMM) and kill cancer cells. However, the mechanism by which CTU disrupts the inner mitochondrial membrane (IMM) and activates apoptosis is not clear. Here, we show that CTU-mediated ROS selectively dysregulated the OMA1/OPA1 fusion regulatory system located in the IMM. The essential role of ROS was confirmed in experiments with the lipid peroxyl scavenger α-tocopherol, which prevented the dysregulation of OMA1/OPA1 and CTU-mediated MDA-MB-231 cell killing. The disruption of OMA1/OPA1 and IMM fusion by CTU-mediated ROS accounted for the release of cytochrome c from the mitochondria and the activation of apoptosis. Taken together, these findings demonstrate that CTU depolarises the mitochondrial membrane, activates ROS production, and disrupts both the IMM and OMM, which releases cytochrome c and activates apoptosis. Mitochondrial-targeting agents like CTU offer a novel approach to the development of new therapeutics with anticancer activity.

Cystic fibrosis (CF) has shifted from a fatal paediatric lung disease to a multi‐organ, lifespan‐spanning disorder in which gastrointestinal (GI) complications and malignancies are increasingly prominent. With improved survival into mid‐ and late adulthood, aided by newborn screening, optimised nutrition and the advent of highly effective CF transmembrane conductance regulator (CFTR) modulators, implementation of colonoscopic surveillance has highlighted a several‐fold increase in early‐onset colorectal cancer (CRC) and a broader spectrum of intestinal pathology. In parallel, work in mouse models, human tissue and patient‐derived intestinal organoids now places the CFTR at the centre of a complex epithelial compartment that integrates ion and pH homeostasis, mucus biology, microbiota, redox balance and immune/stromal function. In this review, we advance the hypothesis that CF may be conceptualised as a niche‐centric hereditary CRC predisposition syndrome, in which germline CFTR dysfunction chronically destabilises epithelial identity in addition to increasing mutational burden. We synthesise evidence that CFTR loss remodels stem cell regulation, promotes hypoxia and oxidative stress, perturbs microbial ecosystems, drives chronic immune activation and stromal remodelling, and induces epithelial–mesenchymal plasticity (EMP) and DNA‐damage vulnerability, collectively creating a pre‐neoplastic intestinal ecosystem. We situate this model within contemporary CRC frameworks that emphasise cell‐state transitions, hybrid epithelial–mesenchymal (E/M) states and specialised stromal niches, and we distinguish it from oncofoetal reprogramming, an APC ‐driven programme that CF does not clearly recapitulate. We propose that CF may provide a naturally occurring human context in which chronic epithelial stress sustains EMP‐like pressure, a concept that requires direct validation in human CF intestinal tissue. Finally, we consider how CFTR modulators, microbiome‐directed therapies and redox‐targeted interventions might re‐programme the CF intestinal niche and outline experimental and clinical strategies needed to determine whether early, ecosystem‐level correction can prevent GI cancers in this high‐risk population.