Medical ozone induces proliferation and migration inhibition through ROS accumulation and PI3K/AKT/NF-κB suppression in human liver cancer cells in vitro

Impact of air pollution on the progress-free survival of non-small cell lung cancer patients with anti-PD-1/PD-L1 immunotherapy: A cohort study

Air pollution is a well-established risk factor for lung cancer, but limited evidence exists on its impact on the treatment of lung cancer. The objective of this study was to investigate the impact of key pollutants on the efficacy of PD-1/PD-L1 inhibitor immunotherapy in non-small cell lung cancer (NSCLC) patients, thereby providing clinicians with evidence to potentially enhance the efficacy of PD-1 therapy and inform policy decisions for cancer care. To this end, we conducted a study involving 361 NSCLC patients who received PD-1/PD-L1 inhibitor immunotherapy, examining the correlation between air pollution exposure and progression-free survival (PFS) following immunotherapy treatment. Their moving-average ambient levels up to 1 year of PM2.5 and its constituents (organic matter (OM), black carbon (BC), nitrate (NO3-), sulfate (SO42-), and ammonium (NH4+)), as well as ozone (O3) were estimated using the Tracking Air Pollution in China dataset. Cox proportional hazards models were adopted to estimate the effects of exposure to each pollutant on PFS risk for NSCLC. 179 patients obtained the progression of NSCLC. While PM2.5 exposure prior to the immunotherapy was not associated with NSCLC progression, long-term exposure to BC and OM, the important organic components of PM2.5, were significantly associated with a higher risk of NSCLC progression with corresponding hazard ratios (HRs, 95% confidence intervals) of 2.42 (1.39, 4.23) and 2.41 (1.40, 4.14) for 1-year moving average, respectively. Short-term exposure to O3 was also associated with PFS with a HR of 1.64 (1.08, 2.50) for 3-month averaged exposure. Monotonic increasing dose-response relationships were further observed for the associations of BC, OM and O3 with PFS. Our findings imply the need of implementing effective measures for targeted reduction in specific sources of PM2.5 constituents (especially BC and OM) and O3 at different time windows to improve the prognosis of NSCLC patients especially for their PFS.

Low-Dose Ozone as a Eustress Inducer: Experimental Evidence of the Molecular Mechanisms Accounting for Its Therapeutic Action

Ozone (O3) is an unstable, highly oxidative gas that rapidly decomposes into oxygen. The therapeutic use of O3 dates back to the beginning of 20th century and is currently based on the application of low doses, inducing moderate oxidative stress that stimulates the antioxidant cellular defences without causing cell damage. In recent decades, experimental investigations allowed the establishment of some basic mechanisms accounting for the therapeutic effects of eustress-inducing low-dose O3. In this review, special attention was given to the impact of O3 administration on the cell oxidant-antioxidant status, O3 anti-inflammatory and analgesic properties, efficacy in improving tissue regeneration, and potential anticancer action. Low O3 concentrations proved to drive the cell antioxidant response mainly by activating nuclear factor erythroid 2-related factor 2. The anti-inflammatory effect relies on the downregulation of pro-inflammatory factors and the modulation of cytokine secretion. The painkilling action is related to anti-inflammatory processes, inhibition of apoptosis and autophagy, and modulation of pain receptors. The regenerative potential depends on antioxidant, anti-inflammatory, anti-apoptotic, and pro-proliferative capabilities, as well as fibroblast activation. Finally, the anticancer potential is based on oxidant and anti-inflammatory properties, as well as the inhibition of cell proliferation, invasion, and migration and the induction of apoptosis.

Dietary modulation of lung lipids influences inflammatory responses to inhaled ozone

The pulmonary system represents a unique lipidomic environment as it contains cellular membrane-bound lipid species and a specialized reservoir of lipids in the airway epithelial lining fluid. As a major initial point of defense, airway lipids react to inhaled contaminants such as volatile organic compounds, oxides of nitrogen, or ozone (O3), creating lipokine signaling that is crucial for both the initiation and resolution of inflammation within the lung. Dietary modulation of eicosanoids has gained increased attention in recent years for improvements to cardiovascular health. The current study sought to examine how dietary supplementation with eicosanoid precursors (i.e, oils rich in saturated or polyunsaturated fatty acids) might alter the lung lipid composition and subsequently modify the inflammatory response to ozone inhalation. Our study demonstrated that mice fed a diet high in saturated fatty acids resulted in diet-specific changes to lung lipid profiles and increased cellular recruitment to the lung following ozone inhalation. Bioinformatic analysis revealed an ozone-dependent upregulation of several lipid species, including phosphoserine 37:5. Pathway analysis of lipid species revealed the process of lateral diffusion of lipids within membranes to be significantly altered due to ozone exposure. These results show promising data for influencing pulmonary lipidomic profiles via diet, which may provide a pragmatic therapeutic approach to protect against lung inflammation and damage following pulmonary insult.

Biological impact and therapeutic perspective of targeting PI3K/Akt signaling in hepatocellular carcinoma: Promises and Challenges

Cancer progression results from activation of various signaling networks. Among these, PI3K/Akt signaling contributes to proliferation, invasion, and inhibition of apoptosis. Hepatocellular carcinoma (HCC) is a primary liver cancer with high incidence rate, especially in regions with high prevalence of viral hepatitis infection. Autoimmune disorders, diabetes mellitus, obesity, alcohol consumption, and inflammation can also lead to initiation and development of HCC. The treatment of HCC depends on the identification of oncogenic factors that lead tumor cells to develop resistance to therapy. The present review article focuses on the role of PI3K/Akt signaling in HCC progression. Activation of PI3K/Akt signaling promotes glucose uptake, favors glycolysis and increases tumor cell proliferation. It inhibits both apoptosis and autophagy while promoting HCC cell survival. PI3K/Akt stimulates epithelial-to-mesenchymal transition (EMT) and increases matrix-metalloproteinase (MMP) expression during HCC metastasis. In addition to increasing colony formation capacity and facilitating the spread of tumor cells, PI3K/Akt signaling stimulates angiogenesis. Therefore, silencing PI3K/Akt signaling prevents aggressive HCC cell behavior. Activation of PI3K/Akt signaling can confer drug resistance, particularly to sorafenib, and decreases the radio-sensitivity of HCC cells. Anti-cancer agents, like phytochemicals and small molecules can suppress PI3K/Akt signaling by limiting HCC progression. Being upregulated in tumor tissues and clinical samples, PI3K/Akt can also be used as a biomarker to predict patients' response to therapy.

Ozone causes depressive-like response through PI3K/Akt/GSK3β pathway modulating synaptic plasticity in young rats

Ozone pollution has been associated with several adverse effects, including memory impairment, intellectual retardation, emotional disturbances. However, the potential mechanisms remain uncertain. The present study aimed to investigate whether ozone (O₃) regulates synaptic plasticity through PI3K/Akt/GSK3β signaling pathway and induces neurobehavioral modifications among the young rats. In vivo, the newborn rats were used to construct the animal model of early postnatal O₃ treatment. In vitro, this study measured the effect of different concentrations of serum from O₃ treated rats on the viability of the PC12 cells, and investigated the modifications of synaptic plasticity and PI3K/Akt/GSK3β signaling pathway in the hippocampus and PC12 cells after O₃ treated. The results revealed significant depression-like behavior and increased hippocampal histopathological damage in the young rats after O₃ treated. Compared with the control group, the expression levels of synaptic related proteins including Drebrin, PSD95, Synaptophysin and PIK3R1, p-Akt, and p-GSK3β were decreased in the O₃ treated group. In vitro assays, a significant reduction in Drebrin, PSD95, Synaptophysin, PIK3R1, p-Akt, and p-GSK3β was found in PC12 cells after O₃ serum treated. While 740Y-P (a specific PI3K activator) administered, the expression levels of Drebrin, PSD95, Synaptophysin, PIK3R1, p-Akt, and p-GSK3β in the 740Y-P + O₃ group were significantly elevated in vivo and vitro compared with the O₃-only group. In addition, miRNAs modulating PIK3R1 were screened on bioinformatics website, the study found aberrant expression of miR-221-3p in the hippocampus and serum of O₃ treated group. Inhibition of miR-221-3p expression effectively reversed the reduction of Drebrin, PSD95, Synaptophysin, PIK3R1, p-Akt, and p-GSK3β in PC12 cells induced by O₃ treatment. Altogether, these studies indicate that O₃ restrained the expression of PI3K/Akt/GSK3β signaling pathway and impaired synaptic plasticity that resulted in depressive-like behavior in young rats. Moreover, miR-221-3p plays an important role in this procedure by regulating PIK3R1.

Effects of circFOXO3 on the Proliferation and Invasion of Liver Cancer Cells by Regulating PI3K/Akt Pathway

Objective

Hepatocellular carcinoma is a malignant disease occurring in the liver and is one of the main causes of death in cancer patients. Tumor cells are the main components of tumors and have a strong proliferative capacity. They are easily transferred to other parts of the body and can produce harmful substances that destroy the normal organ structure and endanger human life and health. In this study, we investigate the effect of circFOXO3 on the proliferation and invasion of hepatocellular carcinoma cells and its possible mechanism.

Methods

Human hepatocellular carcinoma cells BEL-7404, Hep G2, Hep 3B2.1–7, HuH-7, Li-7, and human normal hepatocytes HHL-5 were selected, and the expression level of circFOXO3 in the cell lines was determined by qRT-PCR. The cell line with low circFOXO3 expression level (HuH-7 cells) was used for follow-up experiments. HuH-7 liver cancer cells were divided into the control group (normal cultured), circFOXO3-NC group (transfected with circFOXO3 negative control), circFOXO3 mimic group (transfected with circFOXO3 mimic), PI3K activator group (20 μmol/L PI3K activator 740Y-P), and circFOXO3 mimic + PI3K activator group (transfected with circFOXO3 mimic + treated with PI3K activator 740Y-P). The qRT-PCR method was used to determine the expression level of circFOXO3 in HuH-7 liver cancer cells in each group, WB was used to detect the expression of apoptosis, invasion, and phosphoinositide 3-kinase/protein kinase B (PI3K/Akt) pathway related proteins in HuH-7 liver cancer cells in each group, the CCK-8 method was used to determine the viability of HuH-7 liver cancer cells in each group, flow cytometry was used to determine the apoptotic ability of HuH-7 liver cancer cells in each group, the transwell chamber experiment was used to determine the invasion ability of HuH-7 liver cancer cells in each group, and the scratch test was used to determine the migration ability of HuH-7 liver cancer cells in each group.

Results

circFOXO3 showed low expression in liver cancer cells; compared with the control group, the circFOXO3 expression and apoptosis rate of HuH-7 liver cancer cells in the circFOXO3 mimic group were significantly increased (P < 0.05) and the PI3K/Akt pathway-related protein expression, cell viability, invasion, and migration abilities were significantly reduced (P < 0.05); the apoptosis rate of HuH-7 liver cancer cells in the PI3K activator group was significantly reduced (P < 0.05) and the PI3K/Akt pathway related protein expression, cell viability, invasion and migration abilities were significantly increased (P < 0.05). Compared with the circFOXO3 mimic group, the apoptosis rate of HuH-7 liver cancer cells in the circFOXO3 mimic + PI3K activator group was significantly reduced (P < 0.05) and the PI3K/Akt pathway-related protein expression, cell viability, invasion and migration abilities were significantly increased (P < 0.05).

Conclusion

Highly expressed circFOXO3 can inhibit the proliferation and invasion of HuH-7 liver cancer cells, which may be achieved by inhibiting the PI3K/Akt pathway.

NF-κB as a regulator of cancer metastasis and therapy response: A focus on epithelial-mesenchymal transition

Metastasis of tumor cells is a complex challenge and significantly diminishes the overall survival and prognosis of cancer patients. The epithelial-to-mesenchymal transition (EMT) is a well-known mechanism responsible for the invasiveness of tumor cells. A number of molecular pathways can regulate the EMT mechanism in cancer cells and nuclear factor-kappaB (NF-κB) is one of them. The nuclear translocation of NF-κB p65 can induce the transcription of several genes involved in EMT induction. The present review describes NF-κB and EMT interaction in cancer cells and their association in cancer progression. Due to the oncogenic role NF-κB signaling, its activation enhances metastasis of tumor cells via EMT induction. This has been confirmed in various cancers including brain, breast, lung and gastric cancers, among others. The ZEB1/2, transforming growth factor-β, and Slug as inducers of EMT undergo upregulation by NF-κB to promote metastasis of tumor cells. After EMT induction driven by NF-κB, a significant decrease occurs in E-cadherin levels, while N-cadherin and vimentin levels undergo an increase. The noncoding RNAs can potentially also function as upstream mediators and modulate NF-κB/EMT axis in cancers. Moreover, NF-κB/EMT axis is involved in mediating drug resistance in tumor cells. Thus, suppressing NF-κB/EMT axis can also promote the sensitivity of cancer cells to chemotherapeutic agents.

Ozone treatment alleviates brain injury in cerebral ischemic rats by inhibiting the NF-κB signaling pathway and autophagy

Stroke is the most frequent cause of disability in developed countries. A common phenomenon of stroke, cerebral ischemia, is threatening many lives worldwide. In addition, ozone treatment was previously reported to exert functions in relieving brain injury. In the current study, the therapeutic effects of ozone on cerebral ischemia are investigated. A rat model of middle cerebral artery occlusion (MCAO) was established. The brain water content was calculated by weighing brain tissues, and the 2, 3, 5-triphenyltetrazolium chloride staining was performed to measure brain infarction volume in rats. A colorimetric assay was conducted to examine expression levels of malondialdehyde, superoxide dismutase, catalase, and glutathione in the rat hippocampus. Reverse transcription quantitative polymerase-chain reaction and Western blot analyses were employed to evaluate expression levels of Beclin1, LC3B, p62, and critical factors implicated in the NF-κB signaling pathway. We found that ozone significantly improved the survival rate of MCAO model rats, reduced the cerebral water content, and decreased the neurological scores of ischemic rats. Ozone markedly reduced cerebral ischemia-induced infarction in ischemic rats. Ozone decreased MDA levels and increased SOD, catalase, and GSH levels in the hippocampus of rats. Ozone significantly inhibited autophagy by decreasing Beclin1 and LC3B expression and increasing p62 expression. The ozone inactivated the NF-κB signaling pathway by decreasing the protein levels of TLR4, p-IKKβ, p-IKBα, and p-p65. We conclude that ozone treatment alleviates the brain injury in ischemic rats by suppressing autophagy and inactivating the NF-κB signaling pathway.

Systemic Review: Ozone: A Potential New Chemotherapy

In the last sixty years, publications in reputed journals have shown the preclinical positive effect of ozone gas in cancer cells. However, the translation of these results into clinical practice is far away from success. A comprehensive approach is necessary for this, and oncologists and researchers need guidance from medical specialists with in-depth knowledge of ozone in medicine. In this article, we review the evidence around this question and suggest different potential research lines to those interested in this exciting field.