Atractylodin Induces Apoptosis and Inhibits the Migration of A549 Lung Cancer Cells by Regulating ROS-Mediated Signaling Pathways

FTIR microspectroscopic study of gastric cancer AGS cells apoptosis induced by As2O3

As2O3 has shown significant anti-gastric cancer effects, but the mechanism is still unclear. Thus, biomacromolecular changes induced by As2O3 were investigated by using human gastric cancer AGS cells as the model. Flow cytometry results confirmed that As2O3 induced AGS cells apoptosis. Fourier transform infrared (FTIR) microspectroscopy detected biomacromolecular changes during As2O3-induced AGS cells apoptosis sensitively: IR spectra showed significant changes in the lipids content and the proteins and DNA structure. Peak-area ratios indicated obvious changes in the lipids and DNA content and the proteins structure, while also showing a relatively good linear relationship between A1733/A969 and the apoptosis rate. PCA exhibited significant alteration in nucleic acids while curve fitting further revealed the changes in nucleic acids and proteins. On the whole, our study explored As2O3-induced gastric cancer cells apoptosis in depth on the basis of analyzing biomacromolecular changes, in addition, it also suggested FTIR microspectroscopy to be possibly useful in the research of apoptosis.

Network pharmacology analysis and experimental verification of the antitumor effect and molecular mechanism of isocryptomerin on HepG2 cells

Isocryptomerin (ISO) is a flavonoid isolated from the natural medicine Selaginellae Herba, which has various pharmacological activities. This study investigated the antitumor effect and underlying molecular mechanism of ISO on hepatocellular carcinoma (HCC) HepG2 cells. The cell viability assay revealed that ISO has a considerable killing effect on HCC cell lines. The apoptosis assay showed that ISO induced mitochondria-dependent apoptosis through the Bad/cyto-c/cleaved (cle)-caspase-3/cleaved (cle)-PARP pathway. The network pharmacological analysis found 13 key target genes, and epidermal growth factor receptor (EGFR), AKT, mitogen-activated protein kinase (MAPK), and reactive oxygen species (ROS) signaling pathways were strongly associated with ISO against HCC. Further verification of the results showed that ISO induced apoptosis by increasing p-p38 and p-JNK expression and decreasing p-EGFR, p-SRC, p-ERK, and p-STAT3 expression. Furthermore, ISO induced G0/G1 phase arrest by downregulating p-AKT, Cyclin D, and CDK 4 expression and upregulating p21 and p27 expression in HepG2 cells. Moreover, ISO inhibited HepG2 cell migration by decreasing p-GSK-3β, β-catenin, and N-cadherin expression and increasing E-cadherin expression. Additionally, ISO promoted ROS accumulation in HepG2 cells, and ISO-induced apoptosis, arrest cell cycle, and inhibition of migration were reversed by an ROS scavenger, N-acetyl- l-cysteine. Overall, ISO induced cell apoptosis and cell cycle arrest and inhibited cell migration by ROS-mediated EGFR, AKT, and MAPK signaling pathways in HepG2 cells.

Vitexin Regulates Heat Shock Protein Expression by Modulating ROS Levels Thereby Protecting against Heat-Stress-Induced Apoptosis

Heat stress due to high temperatures can cause heat stroke, pyrexia, heat cramps, heart disease, and respiratory diseases, which seriously affect human health. Vitexin has been shown to alleviate heat stress; however, its mechanism of action remains unclear. Therefore, in this study, we used Caco-2 cells to establish a heat stress model and vitamin C as a positive control to investigate the regulatory effects of vitexin on heat-stress-induced apoptosis and the related mechanisms using Cell Counting Kit-8, flow cytometry, real-time quantitative polymerase chain reaction, and Western blot. The results showed that the mRNA expressions of Hsp27, Hsp70, and Hsp90 induced by heat stress could be effectively inhibited at vitexin concentrations as low as 30 μM. After heat stress prevention and heat stress amelioration in model cells based on this concentration, intracellular reactive oxygen species (ROS) levels and the mRNA level and the protein expression of heat shock proteins (Hsp70 and Hsp90) and apoptotic proteins were reduced. In addition, compared with the heat stress amelioration group, the expression of BCL2 mRNA and its protein (anti-apoptotic protein Bcl-2) increased in the heat stress prevention group, while the expression of BAX, CYCS, CASP3, and PARP1 mRNAs and their proteins (apoptotic proteins Bax, Cytochrome C, cle-Caspase-3, and cle-PARP1) were decreased. In summary, the heat-stress-preventive effect of vitexin was slightly better than its heat-stress-ameliorating effect, and its mechanism may be through the inhibition of intracellular ROS levels and thus the modulation of the expressions of Hsp70 and Hsp90, which in turn protects against heat-stress-induced apoptosis. This study provides a theoretical basis for the prevention and amelioration of heat stress using vitexin.

Implications of reactive oxygen species in lung cancer and exploiting it for therapeutic interventions

Lung cancer is the second (11.4%) most commonly diagnosed cancer and the first (18%) to cause cancer-related deaths worldwide. The incidence of lung cancer varies significantly among men, women, and high and low-middle-income countries. Air pollution, inhalable agents, and tobacco smoking are a few of the critical factors that determine lung cancer incidence and mortality worldwide. Reactive oxygen species are known factors of lung carcinogenesis resulting from the xenobiotics and their mechanistic paths are under critical investigation. Reactive oxygen species exhibit dual roles in cells, as a tumorigenic and anti-proliferative factor, depending on spatiotemporal context. During the precancerous state, ROS promotes cancer origination through oxidative stress and base-pair substitution mutations in pro-oncogenes and tumor suppressor genes. At later stages of tumor progression, they help the cancer cells in invasion, and metastases by activating the NF-kB and MAPK pathways. However, at advanced stages, when ROS exceeds the threshold, it promotes cell cycle arrest and induces apoptosis in cancer cells. ROS activates extrinsic apoptosis through death receptors and intrinsic apoptosis through mitochondrial pathways. Moreover, ROS upregulates the expression of beclin-1 which is a critical component to initiate autophagy, another form of programmed cell death. ROS is additionally involved in an intermediatory step in necroptosis, which catalyzes and accelerates this form of cell death. Various therapeutic interventions have been attempted to exploit this cytotoxic potential of ROS to treat different cancers. Growing body of evidence suggests that ROS is also associated with chemoresistance and cancer cell immunity. Considering the multiple roles of ROS, this review highlights the exploitation of ROS for various therapeutic interventions. However, there are still gaps in the literature on the dual roles of ROS and the involvement of ROS in cancer cell immunity and therapy resistance.

Scorpion Peptide Smp24 Exhibits a Potent Antitumor Effect on Human Lung Cancer Cells by Damaging the Membrane and Cytoskeleton In Vivo and In Vitro

Smp24, a cationic antimicrobial peptide identified from the venom gland of the Egyptian scorpion Scorpio maurus palmatus, shows variable cytotoxicity on various tumor (KG1a, CCRF-CEM and HepG2) and non-tumor (CD34⁺, HRECs, HACAT) cell lines. However, the effects of Smp24 and its mode of action on lung cancer cell lines remain unknown. Herein, the effect of Smp24 on the viability, membrane disruption, cytoskeleton, migration and invasion, and MMP-2/-9 and TIMP-1/-2 expression of human lung cancer cells have been evaluated. In addition, its in vivo antitumor role and acute toxicity were also assessed. In our study, Smp24 was found to suppress the growth of A549, H3122, PC-9, and H460 with IC₅₀ values from about 4.06 to 7.07 µM and show low toxicity to normal cells (MRC-5) with 14.68 µM of IC₅₀. Furthermore, Smp24 could induce necrosis of A549 cells via destroying the integrity of the cell membrane and mitochondrial and nuclear membranes. Additionally, Smp24 suppressed cell motility by damaging the cytoskeleton and altering MMP-2/-9 and TIMP-1/-2 expression. Finally, Smp24 showed effective anticancer protection in a A549 xenograft mice model and low acute toxicity. Overall, these findings indicate that Smp24 significantly exerts an antitumor effect due to its induction of membrane defects and cytoskeleton disruption. Accordingly, our findings will open an avenue for developing scorpion venom peptides into chemotherapeutic agents targeting lung cancer cells.