Mimicking Tumor Metastasis Using a Transwell-Integrated Organoids-On-a-Chip Platform.

The mortality rate among cancer patients is primarily attributed to tumor metastasis. The evaluation of metastasis potential provides a powerful framework for personalized therapies. However, little work has so far been undertaken to precisely model tumor metastasis in vitro, hindering the development of preventive and therapeutic interventions. In this work, a tumor-metastasis-mimicked Transwell-integrated organoids-on-a-chip platform (TOP) for precisely evaluating tumor metastatic potential is developed. Unlike the conventional Transwell device for detecting cell migration, the engineered device facilitates the assessment of metastasis in patient-derived organoids (PDO). Furthermore, a novel Transwell chamber with a hexagon-shaped structure is developed to mimic the migration of tumor cells into surrounding tissues, allowing for the evaluation of tumor metastasis in a horizontal direction. As a proof-of-concept demonstration, tumor organoids and metastatic clusters are further evaluated at the protein, genetic, and phenotypic levels. In addition, preliminary drug screening is undertaken to highlight the potential for using the device to combat cancers. In summary, the tumor-metastasis-mimicked TOP offers unique capabilities for evaluating the metastasis potential of tumor organoids and contributes to the development of personalized cancer therapies.

Association of multiple air pollutants with oxygen saturation during sleep in COPD patients: Effect modification by smoking status and airway inflammatory phenotypes.

Air pollution contributes substantially to the development of chronic obstructive pulmonary disease (COPD). To date, the effect of air pollution on oxygen saturation (SpO2) during sleep and potential susceptibility factors remain unknown. In this longitudinal panel study, real-time SpO2 was monitored in 132 COPD patients, with 270 nights (1615 h) of sleep SpO2 recorded. Exhaled nitric oxide (NO), hydrogen sulfide (H2S) and carbon monoxide (CO) were measured to assess airway inflammatory characteristics. Exposure levels of air pollutants were estimated by infiltration factor method. Generalized estimating equation was used to investigate the effect of air pollutants on sleep SpO2. Ozone, even at low levels (<60 µg/m3), was significantly associated with decreased SpO2 and extended time of oxygen desaturation (SpO2 < 90%), especially in the warm season. The associations of other pollutants with SpO2 were weak, but significant adverse effects of PM10 and SO2 were observed in the cold season. Notably, stronger effects of ozone were observed in current smokers. Consistently, smoking-related airway inflammation, characterized by higher levels of exhaled CO and H2S but lower NO, significantly augmented the effect of ozone on SpO2 during sleep. This study highlights the importance of ozone control in protecting sleep health in COPD patients.