Lactate drives CD38 signaling to promote Epithelial-Mesenchymal Transition through Snail induction in non-small cell lung cancer cells.

CD38 is the main NADase in mammalian cells. It regulates the homeostasis of nicotinamide adenine dinucleotide (NAD+) and extracellular nucleotides. Its function plays an important role in infection and aging. However, its potential functions in tumor cells have not been fully elucidated. In the present study, we demonstrated that lactate, which is derived from tumor metabolism remodeling, upregulates the expression of CD38 through OXPHOS-driven Hippo-TAZ pathway. The highly expressed CD38 converts NAD + to adenosine through the CD203a/CD73 complex and adenosine binds and activates its receptor A2AR, inducing the expression of Snail and promoting the invasion and metastasis of lung cancer cells. This finding elucidates a new perspective on the interplay between NAD + metabolism and glycolysis in tumor development.

Clinical efficiency of three-port inflatable robot-assisted thoracoscopic surgery in mediastinal tumor resection.

BACKGROUND: Aimed to assess clinical effect of three-port inflatable robot-assisted thoracoscopic surgery in mediastinal tumor resection by comparing results of the robot group with the video group. METHODS: Retrospectively analyze 179 patients diagnosed with anterior mediastinal tumor from May 2017 to August 2021. Two groups were divided according to the surgical approach, including 92 cases in the RATS group and 87 cases in the VATS group. The results were analyzed between two groups with variables of age, sex, BMI, tumor size, and diagnosis. Perioperative clinical data was gathered to compare. RESULT: There were no significant differences between the 2 groups with regards to demographic data and clinical features. There were no significant differences inoperative time and duration of chest tube via RATS vs. VATS. The intraoperative blood loss was statistically significantly different among the RATS and VATS groups (75.9 ± 39.6 vs. 97.4 ± 35.8 ml p = 0.042). The postoperative stay of patients in RATS group were significantly shorter than that in VATS group (2.3 ± 1.0 vs. 3.4 ± 1.4 day p = 0.035), CONCLUSION: Three-port inflatable robot-assisted thoracoscopic surgery for mediastinal tumor is feasible and reliable it is more advantageous, and it provides the surgeon with advice on treatment choice.

Antioxidant properties of polyphenols from snow chrysanthemum (Coreopsis tinctoria) and the modulation on intestinal microflora in vitro.

CONTEXT: Coreopsis tinctoria Nutt (Asteraceae), named snow chrysanthemum, is known to have a high level of polyphenols. However, the potential prebiotic effect on modulating intestinal microflora is still unclear. OBJECTIVE: The chemical composition, antioxidant properties of snow chrysanthemum polyphenols (SCPs) and their effects on human intestinal microbiota were investigated. MATERIALS AND METHODS: SCPs were extracted using ultrasonic-assisted extraction, and further determined using UPLC-QE Orbitrap/MS. Five assays were used to investigate the antioxidant activities of SCPs. Subsequently, the effects of SCPs on intestinal microbiota in vitro were determined by high throughput sequencing and bioinformatics analysis. RESULTS: Marein, isookanin and cymaroside were the major phenolic compounds, which accounted for 42.17%, 19.53% and 12.25%, respectively. Marein exhibited higher scavenging capacities in DPPH (EC50 = 8.84 µg/mL) and super anion radical assay (EC50 = 282.1 µg/mL) compared to cymaroside and isookanin. The antioxidant capacity of cymaroside was weakest among the three phenolic compounds due to the highest EC50 values, especially for superoxide anion radical assay, EC50 > 800 µg/mL. The result of in vitro fermentation showed that the three phenolic compounds increased the relative abundances of Escherichia/Shigella, Enterococcus, Klebsiella, etc., and isookanin notably increased the relative abundance of Bifidobacterium and Lactobacillus. DISCUSSION AND CONCLUSIONS: SCPs exhibited antioxidant properties and potential prebiotic effects on modulating the gut microbiota composition. The findings indicated that SCPs consumption could exert prebiotic activity that is beneficial for human health.

A lactate-induced Snail/STAT3 pathway drives GPR81 expression in lung cancer cells.

Highly expressed G protein-coupled receptor 81 (GPR81), a receptor for lactate, is emerging as a critical regulator of tumor growth and metastasis. However, the mechanistic basis for its highly expression in cancer cells remains elusive. Here we report that tumor-derived lactate transcriptionally regulates GPR81 expression. We demonstrated that the transcriptional response of GPR81 to lactate is mediated by Signal transducer and activator of transcription 3 (STAT3). Mechanistically, lactate upregulates transcriptional factor Snail and induces the assembly of Snail/EZH2/STAT3 complex. Within this ternary complex, STAT3 activity is strongly enhanced. Consequently, the activated STAT3 by lactate directly binds GPR81promoter and activates its expression. These findings shed light on the transcriptional mechanism by which GPR81 expression is regulated in cancer cells, and provides mechanistic insight into how aberrant signaling and continually high lactate levels due to metabolic switch may yield a feed-forward/self-enabling loop to promote tumor progression.