Acacetin induces sustained ERK1/2 activation and RIP1-dependent necroptotic death in breast cancer cells

Effect of acacetin on inhibition of apoptosis in Helicobacter pylori-infected gastric epithelial cell line

BACKGROUND

Helicobacter pylori (H. pylori) infection can cause extensive apoptosis of gastric epithelial cells, serving as a critical catalyst in the progression from chronic gastritis, gastrointestinal metaplasia, and atypical gastric hyperplasia to gastric carcinoma. Prompt eradication of H. pylori is paramount for ameliorating the pathophysiological conditions associated with chronic inflammation of the gastric mucosa and the primary prevention of gastric cancer. Acacetin, which has multifaceted pharmacological activities such as anti-cancer, anti-inflammatory, and antioxidative properties, has been extensively investigated across various domains. Nevertheless, the impact and underlying mechanisms of action of acacetin on H. pylori-infected gastric mucosal epithelial cells remain unclear.

AIM

To explore the defensive effects of acacetin on apoptosis in H. pylori-infected GES-1 cells and to investigate the underlying mechanisms.

METHODS

GES-1 cells were treated with H. pylori and acacetin in vitro. Cell viability was assessed using the CCK-8 assay, cell mortality rate via lactate dehydrogenase assay, alterations in cell migration and healing capacities through the wound healing assay, rates of apoptosis via flow cytometry and TUNEL staining, and expression levels of apoptosis-associated proteins through western blot analysis.

RESULTS

H. pylori infection led to decreased GES-1 cell viability, increased cell mortality, suppressed cell migration, increased rate of apoptosis, increased expressions of Bax and cle-caspase3, and decreased Bcl-2 expression. Conversely, acacetin treatment enhanced cell viability, mitigated apoptosis induced by H. pylori infection, and modulated the expression of apoptosis-regulatory proteins by upregulating Bcl-2 and downregulating Bax and cleaved caspase-3.

CONCLUSION

Acacetin significantly improved GES-1 cell viability and inhibited apoptosis in H. pylori-infected GES-1 cells, thereby exerting a protective effect on gastric mucosal epithelial cells.

7-O-tyrosyl Silybin Derivatives as a Novel Set of Anti-Prostate Cancer Compounds

Silybin is a natural compound extensively studied for its hepatoprotective, neuroprotective and anticancer properties. Envisioning the enhancement of silybin potential by suitable modifications in its chemical structure, here, a series of new 7-O-alkyl silybins derivatives were synthesized by the Mitsunobu reaction starting from the silybins and tyrosol-based phenols, such as tyrosol (TYR, 3), 3-methoxytyrosol (MTYR, 4), and 3-hydroxytyrosol (HTYR, 5). This research sought to explore the antioxidant and anticancer properties of eighteen new derivatives and their mechanisms. In particular, the antioxidant properties of new derivatives outlined by the DPPH assay showed a very pronounced activity depending on the tyrosyl moiety (HTYR > MTYR >> TYR). A significant contribution of the HTYR moiety was observed for silybins and 2,3-dehydro-silybin-based derivatives. According to the very potent antioxidant activity, 2,3-dehydro-silybin derivatives 15ab, 15a, and 15b exerted the most potent anticancer activity in human prostate cancer PC-3 cells. Furthermore, flow cytometric analysis for cell cycle and apoptosis revealed that 15ab, 15a, and 15b induce strong G1 phase arrest and increase late apoptotic population in PC-3 cells. Additionally, Western blotting for apoptotic marker cleaved caspase-3 confirmed apoptosis induction by these silybin derivatives in PC-3 cells. These findings hold significant importance in the investigation of anticancer properties of silybin derivatives and strongly encourage swift investigation in pre-clinical models and clinical trials.

Ferroptosis: Potential opportunities for natural products in cancer therapy

Cancer cells often exhibit defects in the execution of cell death, resulting in poor clinical outcomes for patients with many cancer types. Ferroptosis is a newly discovered form of programmed cell death characterized by intracellular iron overload and lipid peroxidation in the cell membrane. Increasing evidence suggests that ferroptosis is closely associated with a wide variety of physiological and pathological processes, particularly in cancer. Notably, various bioactive natural products have been shown to induce the initiation and execution of ferroptosis in cancer cells, thereby exerting anticancer effects. In this review, we summarize the core regulatory mechanisms of ferroptosis and the multifaceted roles of ferroptosis in cancer. Importantly, we focus on natural products that regulate ferroptosis in cancer cells, such as terpenoids, polyphenols, alkaloids, steroids, quinones, and polysaccharides. The clinical efficacy, adverse effects, and drug-drug interactions of these natural products need to be evaluated in further high-quality studies to accelerate their application in cancer treatment.

Phenylarsine oxide induced corneal injury involves oxidative stress mediated unfolded protein response and ferroptotic cell death: Amelioration by NAC

Phenylarsine oxide (PAO), an analog of lewisite, is a highly toxic trivalent arsenical and a potential chemical warfare agent. PAO-induced toxicity has been studied in lung, liver, and skin tissues. Nevertheless, very few studies have been published to comprehend the impact of PAO-induced toxicity on ocular tissues, even though eyes are uniquely vulnerable to injury by vesicants. Notably, arsenical vesicants such as lewisite have been shown to cause edema of eyelids, inflammation, massive corneal necrosis, and blindness. Accordingly, human corneal epithelial cells were used to study the effects of PAO exposure. PAO (100 and 200 nM) induced significant oxidative stress in corneal epithelial cells. Simultaneous treatment with N-acetyl-l-cysteine (NAC), an FDA-approved antioxidant, reversed the PAO-induced toxicity in human corneal epithelial cells. Furthermore, oxidative stress induction by PAO was accompanied by unfolded protein response (UPR) signaling activation and ferroptotic cell death. Further, to validate the findings of our in vitro studies, we optimized injury biomarkers and developed an ex vivo rabbit corneal culture model of PAO exposure. Investigations using PAO in ex vivo rabbit corneas revealed similar results. PAO (5 or 10 μg) for 3, 5, and 10 min caused moderate to extensive corneal epithelial layer degradation and reduced the epithelial layer thickness in a concentration- and time-dependent manner. Similar to human corneal cells, injuries by PAO in ex vivo cultured rabbit corneas were also associated with elevated oxidative stress, UPR signaling, and ferroptosis induction. NAC mitigated PAO-induced corneal injuries in rabbit ex vivo cornea culture as well. The reversal of PAO toxicity upon NAC treatment observed in our studies could be attributed to its antioxidant properties. These findings suggest that PAO exposure can cause significant corneal injury and highlight the need for further mechanistic studies to better understand the pathobiology of different arsenical vesicants, including PAO and lewisite.

Jaceosidin inhibits the progression and metastasis of NSCLC by regulating miR-34c-3p/Integrin α2β1 axis

Non-coding RNAs are crucial for cancer progression, among which miR-34c-3p has been demonstrated to be a tumor suppressor in non-small cell lung cancer (NSCLC). In this study, we attempt to identify flavonoids that can up-regulate miR-34c-3p expression, evaluate the anticancer activity of the flavonoids and explore its underlying mechanism in NSCLC cells. Six flavonoids were screened by RT-qPCR and we found that jaceosidin significantly increased miR-34c-3p expression in A549 cells. We found that jaceosidin inhibited the proliferation, migration and invasion of A549 and H1975 cells in a dose-relevant manner, indicated by cell counting kit (CCK-8) assay, wound healing assay, transwell assay and EdU assay, we observed that jaceosidin inhibited the proliferation, migration and invasion of A549 and H1975 cells in a dose-relevant manner. Further research suggested that miR-34c-3p bound to the transcriptome of integrin α2β1 and then inhibited its expression, leading to the inhibitory effect on the migration and invasion of NSCLC. Our study sheds some light on anti-tumor of jaceosidin and provides a potential lead compound for NSCLC therapy.