Transcriptomic changes in oxidative stress, immunity, and cancer pathways caused by cannabis vapor on alveolar epithelial cells

As legalization of cannabis increases worldwide, vaping cannabis is gaining popularity due to the belief that it is less harmful than smoking cannabis. However, the safety of cannabis vaping remains untested. To address this, we developed a physiologically relevant method for in vitro assessment of cannabis vapor on alveolar epithelial cell cultures. We compared the transcriptional response in three in vitro models of cannabis vapor exposure using A549 epithelial cells in submerged culture, pseudo-air liquid interface (ALI) culture, and ALI culture coupled with the expoCube™ advanced exposure system. Baseline gene expression in ALI-maintained A549 cells showed higher expression of type 2 alveolar epithelial (AEC2) genes related to surfactant production, ion movement, and barrier integrity. Acute exposure to cannabis vapor significantly affected gene expression in AEC2 cells belonging to pathways related to cancer, oxidative stress, and the immune response without being associated with a DNA damage response. This study identifies potential risks of cannabis vaping and underscores the need for further exploration into its respiratory health implications.