Objective: Obstructive sleep apnea (OSA) is associated with severity of pneumonia; however, the mechanism by which OSA promotes lung cancer progression is unclear.
Methods: Twenty-five lung cancer patients were recruited to investigate the relationship between OSA and cancer-associated fibroblast (CAFs) activation. Lung cancer cells (A549) and WI38 fibroblast cells were used to explore the hypoxia-induced TGFβ expression using qPCR, Western blot, and ELISA. Wound healing and transwell assays were performed to evaluate cancer cell migration and invasion. A549 or A549-Luc + WI38 xenograft mouse models were established to detect the intermittent hypoxia (IH) associated with lung tumor growth and epithelial-mesenchymal transition (EMT) in vivo.
Results: OSA promotes CAF activation and enrichment in lung cancer patients. Hypoxia (OSA-like treatment) activated TGFβ signaling in both lung cancer cells and fibroblasts, which promoted cancer cell migration and invasion, and enriched CAFs. IH promoted the progression and EMT process of lung cancer xenograft tumor. Co-inoculation of lung cancer cells and fibroblast cells could further promote lung cancer progression.
Conclusions: IH promotes lung cancer progression by upregulating TGFβ signaling, promoting lung cancer cell migration, and increasing the CAF activation and proportion of lung tumors.
Elevated D-dimer levels at hospital admission may also indicate a higher likelihood of progressing to a severe or critical state. This study aimed to assess reactive oxygen species (ROS), non-enzymatic antioxidant reduced glutathione (GSH), and D-dimer levels in COVID-19 patients upon admission, examining their association with mortality outcomes. Data was collected from the medical records of 170 patients hospitalized in a referral hospital unit between March 2020 and December 2021. Patients were divided into two groups: the ward bed group (n = 87), comprising 51% with moderate clinical conditions, and the intensive care unit (ICU) group (n = 83), comprising 49% with severe conditions. The mean age was 59.4 years, with a male predominance of 52.4%. The overall death rate was 43%, with 30.6% in the moderate group and 69.4% in the severe group. The average time from symptom onset to hospitalization was 6.42 days. Results showed that non-survivors had high D-dimer and ROS counts, longer ICU stays, and worse saturation levels at admission. In conclusion, elevated ROS and D-dimer levels may contribute to worse outcomes in critically ill patients, potentially serving as specific and sensitive predictors of poor outcomes upon admission.
Melittin, a naturally occurring polypeptide found in bee venom, has been recognized for its potential anti-tumor effects, particularly in the context of lung cancer. Our previous study focused on its impact on human lung adenocarcinoma cells A549, revealing that melittin induces intracellular reactive oxygen species (ROS) burst and oxidative damage, resulting in cell death. Considering the significant role of mitochondria in maintaining intracellular redox levels and ROS, we further examined the involvement of mitochondrial damage in melittin-induced apoptosis in lung cancer cells. Our findings demonstrated that melittin caused changes in mitochondrial membrane potential (MMP), triggered mitochondrial ROS burst (Figure 1), and activated the mitochondria-related apoptosis pathway Bax/Bcl-2 by directly targeting mitochondria in A549 cells (Figure 2). Further, we infected A549 cells using a lentivirus that can express melittin-Myc and confirmed that melittin can directly target binding to mitochondria, causing the biological effects described above (Figure 2). Notably, melittin induced mitochondrial damage while inhibiting autophagy, resulting in abnormal degradation of damaged mitochondria (Figure 5). To summarize, our study unveils that melittin targets mitochondria, causing mitochondrial damage, and inhibits the autophagy-lysosomal degradation pathway. This process triggers mitoROS burst and ultimately activates the mitochondria-associated Bax/Bcl-2 apoptotic signaling pathways in A549 cells.
Objectives: Infection remains current as an important discussion topic in the etiological factors of atherosclerosis. Ischemic-modified albumin (IMA), galectin-3 (gal-3), paraoxonase-1 (PON-1), and myeloperoxidase (MPO) are biomolecules that play an important role in the pathogenesis of atherosclerosis. Our aim is to investigate serum IMA, gal-3, PON-1, and MPO activity in acute brucellosis infection.
Materials and methods: Forty patients with acute brucellosis and 40 healthy individuals were included in the study. Serum IMA, gal-3, PON-1, and MPO activity were analyzed by the ELISA method.
Results: In acute brucellosis infection, serum gal-3, IMA, and MPO activities were found to be significantly increased compared to the control group, and PON-1 activity was found to be significantly decreased compared to the control group (p < 0.001). There was a positive correlation between serum IMA, and MPO activity (r = 0.707 p = 0.000) and a negative correlation (r = -0.943, p = 0.000) between PON-1 activity. There was a positive correlation between serum gal-3 and MPO activity (r = 0.683, p = 0.000) and IMA level (r = 0.927, p = 0.000) and a negative correlation between PON-1 activity (r = -0.951, p = 0.000).Conclusion, it was found that serum gal-3, IMA levels and MPO activity increased, while PON-1 activity decreased. These results showed that the oxidant-anti-oxidant balance is impaired in acute brucellosis infection. In addition, these results indicate that brucella infection may be increase the risk of atherosclerosis. Further studies are needed to support our findings.