Machine learning for identifying tumor stemness genes and developing prognostic model in gastric cancer.

Gastric cancer presents a formidable challenge, marked by its debilitating nature and often dire prognosis. Emerging evidence underscores the pivotal role of tumor stem cells in exacerbating treatment resistance and fueling disease recurrence in gastric cancer. Thus, the identification of genes contributing to tumor stemness assumes paramount importance. Employing a comprehensive approach encompassing ssGSEA, WGCNA, and various machine learning algorithms, this study endeavors to delineate tumor stemness key genes (TSKGs). Subsequently, these genes were harnessed to construct a prognostic model, termed the Tumor Stemness Risk Genes Prognostic Model (TSRGPM). Through PCA, Cox regression analysis and ROC curve analysis, the efficacy of Tumor Stemness Risk Scores (TSRS) in stratifying patient risk profiles was underscored, affirming its ability as an independent prognostic indicator. Notably, the TSRS exhibited a significant correlation with lymph node metastasis in gastric cancer. Furthermore, leveraging algorithms such as CIBERSORT to dissect immune infiltration patterns revealed a notable association between TSRS and monocytes and other cell. Subsequent scrutiny of tumor stemness risk genes (TSRGs) culminated in the identification of CDC25A for detailed investigation. Bioinformatics analyses unveil CDC25A's implication in driving the malignant phenotype of tumors, with a discernible impact on cell proliferation and DNA replication in gastric cancer. Noteworthy validation through in vitro experiments corroborated the bioinformatics findings, elucidating the pivotal role of CDC25A expression in modulating tumor stemness in gastric cancer. In summation, the established and validated TSRGPM holds promise in prognostication and delineation of potential therapeutic targets, thus heralding a pivotal stride towards personalized management of this malignancy.

Application of Dexmedetomidine Intravenously Infusion Before Induction of Anesthesia in Segmentectomy of Lung Cancer Patients.

Objective: To study the application of dexmedetomidine in pulmonary segment resection in lung cancer patients. Methods: A total of 120 patients with lung cancer who underwent segmentectomy in our hospital from January 2021 to January 2022 were selected and divided into a control group (60 cases) and a study group (60 cases) according to the lottery method. Early lung cancer was diagnosed by histopathology and imaging, which was in line with the indication of segmental pneumonectomy, and was not treated by radiotherapy, chemotherapy, and other means.Exclusion criteria: Patients with coagulation system diseases, middle and late-stage patients and distant metastasis were excluded. Before induction of anesthesia, the control group was injected with normal saline 0.6 µg/kg, and the study group was injected with dexmedetomidine 0.6 µg/kg. Before anesthesia induction (T0), ventilation for 0.5 h (T2), ventilation for 1 h (T2), and immediately after surgery (T3), the changes of hemodynamics, physiological stress, and internal environment stability indexes were analyzed, and adverse reactions and pulmonary symptoms were counted. Incidence of injury and cognitive impairment. Results: The comparison of the observation indicators at T0 time point of the two patient groups was insignificant (P > .05). The T1-T3 point had no significant fluctuation in the study group compared with the T0 point (P > .05). The T1-T3 point in the control group was significantly higher than the T0 point MAP, HR, PaO2, SOD, Cor decreased, PaCO2, MDA, ACTH increased, with obvious fluctuations (P < .05); T1 ~ T3, compared with the control group, the study group MAP, HR, PaO2, SOD, Cor increased, PaCO2, MDA, ACTH decreased (P < .05). There was no significant comparison of adverse reactions between the two groups (P > .05). Compared with the control group, lung injury and cognitive impairment incidence in the study group was lower (P < .05). Conclusion: Before anesthesia induction, intravenous injection of dexmedetomidine can maintain hemodynamic and internal environment stability in lung cancer patients, reduce stress damage to the body, and reduce the incidence of lung injury and cognitive impairment, with high application value. This will reduce the pain of patients in clinical.

Total Flavones of Rhododendron simsii Planch Flower Protect against Cerebral Ischemia-Reperfusion Injury via the Mechanism of Cystathionine-γ-Lyase-Produced H2S.

Total flavones of Rhododendron simsii Planch flower (TFR) have a significant protective effect against cerebral ischemia-reperfusion injury. However, its mechanism is unclear. This study investigated the protection of TFR against cerebral ischemia-reperfusion injury via cystathionine-γ-lyase- (CSE-) produced H2S mechanism. CSE-/- mice and CSE-siRNA-transfected rat were used. Relaxation of cerebral basilar artery (CBA), H2S, and CSE mRNA were measured. TFR significantly inhibited cerebral ischemia-reperfusion-induced abnormal neurological symptom and cerebral infarct in the normal rats and the CSE+/+ mice, but not in the CSE-/- mice, and the inhibition was markedly attenuated in CSE-siRNA-transfected rat; TFR elicited a significant vasorelaxation in rat CBA, and the relaxation was markedly attenuated by removal of endothelium or CSE-siRNA transfection or coapplication of NO synthase inhibitor L-NAME and PGI2 synthase inhibitor Indo. CSE inhibitor PPG drastically inhibited TFR-evoked vasodilatation resistant to L-NAME and Indo in endothelium-intact rat CBA. TFR significantly increased CSE mRNA expression in rat CBA endothelial cells and H2S production in rat endothelium-intact CBA. The increase of H2S production resistant to L-NAME and Indo was abolished by PPG. Our data indicate that TFR has a protective effect against the cerebral ischemia-reperfusion injury via CSE-produced H2S and endothelial NO and/or PGI2 to relax the cerebral artery.

Involvement of Hydrogen Sulfide in Endothelium-Derived Relaxing Factor-Mediated Responses in Rat Cerebral Arteries.

BACKGROUND/AIM: H2S is a novel vasoactivator. To verify the hypothesis that H2S may act as an endothelium-derived hyperpolarizing factor (EDHF) in the rat cerebrovasculature, the role of H2S in endothelium-derived relaxing factor (EDRF)-mediated responses was investigated. METHODS: Cystathionine-γ-lyase (CSE) was knocked down with an siRNA technique. Artery diameter, hyperpolarization and Ca2+-activated K+ (KCa) current were measured. RESULTS: CSE knockdown was indicated by a decrease in protein and mRNA expression in the rat middle cerebral artery (MCA) and cerebral basilar artery (CBA). Acetylcholine (ACh) induced significant hyperpolarization and vasodilation in endothelium-intact MCA and CBA. Removal of the endothelium abolished these responses. The nitric oxide (NO) synthase inhibitor L-NAME, but not the PGI2 production inhibitor indomethacin, significantly inhibited ACh-induced hyperpolarization and vasodilation in the CBA. In the presence of L-NAME and indomethacin, ACh-induced hyperpolarization and vasodilation in the MCA and CBA were attenuated. The non-NO/PGI2-mediated responses were abolished by the KCa channel blockers charybdotoxin and apamin. In the cerebral arteries from the CSE knockdown rat, non-NO/PGI2-mediated responses were significantly attenuated, and the remaining responses were abolished by charybdotoxin and apamin or the CSE inhibitor propargylglycine. CSE knockdown did not affect L-NAME-sensitive responses in the CBA. Sodium hydrosulfide (NaHS) augmented the KCa current in CBA vascular smooth muscle cells. CONCLUSION: EDHF-mediated responses in rat cerebral arteries were due to H2S activating the KCa channel.

Sirtuin 6 is essential for sodium sulfide-mediated cytoprotective effect in ischemia/reperfusion-stimulated brain endothelial cells.

BACKGROUND: Our recent data demonstrated that hydrogen sulfide (H2S), the third gaseous transmitter, had a protective effect on stroke. The purpose of this study was to investigate the protective effect of H2S in oxygen glucose deprivation and reperfusion (OGD/R)-stimulated brain endothelial cells and its association with sirtuin 6 (SIRT6). METHODS: Cultured bEnd.3 brain endothelial cells were exposed to OGD/R. The effects of sodium sulfide (Na2S, an exogenous H2S donor) on cell death, lactate dehydrogenase release, intracellular reactive oxygen species (ROS) production, superoxide dismutase (SOD) and catalase (CAT) activities, H2S level, cystathionine γ-lyase (CSE) expression, and sirtuin 6 (SIRT6) expression/activity were tested to elucidate the protective mechanisms of H2S. RESULTS: Application of Na2S concentration dependently reduced OGD/R-induced cell death, accompanying with decreasing intracellular ROS production and increasing activities of SOD and CAT. In addition, Na2S also enhanced H2S level and CSE expression associated with upregulation of SIRT6 expression and activity in OGD/R-stimulated brain endothelial cells, whereas CSE inhibitor DL-propargylglycine further deteriorated the decrease of SIRT6 expression and activity as well as the reduction of H2S level and CSE expression caused by OGD/R. Furthermore, SIRT6 knockdown abolished Na2S-mediated CSE expression and cytoprotection action in OGD/R-stimulated cells. CONCLUSIONS: Na2S protected brain endothelial cells against simulated ischemic injury through SIRT6-dependent mechanisms.