Alexandra Bartolomucci

Abstract Circulating tumor DNA (ctDNA) has emerged as a dynamic biomarker in cancer, as evidenced by its increasing integration into clinical practice. Carrying tumor specific characteristics, ctDNA can be used to inform treatment selection, monitor response, and identify drug resistance. In this review, we provide a comprehensive, up-to-date summary of ctDNA in monitoring treatment response with a focus on lung, colorectal, and breast cancers, and discuss current challenges and future directions.

3.1 Low-level chronic JUUL aerosol exposure causes pulmonary inflammation We previously published that an acute exposure to JUUL aerosols using an exposure regime that mimics a light or occasional user has minimal effect on lung inflammation.39 However, there is concern that chronic use may lead to lung damage over time. Therefore, we now tested whether this same exposure scenario—but for a prolonged period of exposure (i.e., 4 weeks)—would cause an inflammatory response in the lungs and airways.