Curzerene suppresses progression of human glioblastoma through inhibition of glutathione S-transferase A4

Anticancer activity of Curcuma aeroginosa essential oil and its nano-formulations: cytotoxicity, apoptosis and cell migration effects

BACKGROUND AND AIMS

Curcuma aeruginosa, commonly known as "kha-min-dam" in Thai, holds significance in Asian traditional medicine due to its potential in treating various diseases, having properties such as anti-HIV, hepatoprotective, antimicrobial and anti-androgenic activities. This study explores the anticancer activity of C. aeruginosa essential oil (CAEO) and its nano-formulations.

METHODS

CAEO obtained from hydrodistillation of C. aeruginosa fresh rhizomes was examined by gas chromatography mass spectroscopy. Cytotoxicity of CAEO was determined in leukaemic K562 and breast cancer MCF-7 cell lines using an MTT assay. Cell cycle analysis and cell apoptosis were determined by flow cytometry. Cell migration was studied through a wound-healing assay.

RESULTS

Benzofuran (33.20%) emerged as the major compound of CAEO, followed by Germacrene B (19.12%) and Germacrone (13.60%). Two types of CAEO loaded nano-formulations, nanoemulsion (NE) and microemulsion (ME) were developed. The average droplet sizes of NE and ME were 13.8 ± 0.2 and 21.2 ± 0.2 nm, respectively. In a comparison with other essential oils from the fresh rhizomes of potential plants from the same family (Curcuma longa, Curcuma mangga and Zingiber officinale) on anticancer activity against K562 and MCF-7 cell lines, CAEO exhibited the highest cytotoxicity with IC50 of 13.43 ± 1.09 and 20.18 ± 1.20 µg/mL, respectively. Flow cytometry analysis revealed that CAEO significantly increased cell death, evidenced from the sub-G1 populations in the cell cycle assay and triggered apoptosis. Additionally, CAEO effectively inhibited cell migration in MCF-7 cells after incubation for 12 and 24 h. The developed NE and ME formulations significantly enhanced the cytotoxicity of CAEO against K562 cells with an IC50 of 45.30 ± 1.49 and 41.98 ± 0.96 µg/mL, respectively.

CONCLUSION

This study's finding suggest that both nano-formulations, NE and ME, effectively facilitated the delivery of CAEO into cancer cells.

DNA methylation and mRNA expression of glutathione S-transferase alpha 4 are associated with intracranial aneurysms in a gender-dependent manner

Objective: We performed a case-control study to investigate the correlation between DNA methylation and mRNA expression of the glutathione S-transferase alpha 4 (GSTA4) gene and the risk of intracranial aneurysm (IA) in the Chinese Han population. Methods: After propensity score matching, 44 pairs of cases and controls were collected in this study. Fasting blood samples were collected for DNA and RNA extraction within 24 h of admission. Nine CpG dinucleotides were selected from the GSTA4 promoter region for DNA methylation pyrosequencing. mRNA expression of GSTA4 was measured by quantitative real-time polymerase chain reaction (RT-qPCR). In vitro cell experiments were conducted to verify the association between 5-aza-2'-deoxycytidine induced DNA hypomethylation and GSTA4 mRNA expression. Results: The mean methylation level of GSTA4 was much lower in IA patients, especially in IA patients, especially in unruptured IA (UIA), than that in controls (IA vs. Control, p < .001; ruptured IA (RIA) vs. Control, p = .005; UIA vs. Control, p < .001). With sex stratification, we further found that the association between GSTA4 methylation and IA risk presented only in women (mean methylation level: IA vs. Control, p < .001; RIA vs. Control, p = .009; UIA vs. Control, p < .001). GSTA4 mRNA expression was significantly higher in the IA group than in the control group (p < .01) and negatively correlated with DNA methylation in all individuals (r = -.746, p < .001). DNA hypomethylation can increase GSTA4 mRNA expression in human primary artery smooth muscle cells. The receiver operating characteristic (ROC) curve showed that GSTA4 mean methylation (AUC = .80, p < .001) was a reliable predictor of women intracranial aneurysm, among which CpG 1 exhibited the best predictive value (AUC = .89, p < .001). In addition, GSTA4 expression levels could also predict the risk of IA in women (AUC = .87, p = .005). Conclusion: Decreased DNA methylation and increased mRNA expression of the GSTA4 gene are associated with the risk of IA in women.

Pump proton inhibitors display anti-tumour potential in glioma

OBJECTIVES

Glioma is one of the most aggressive brain tumours with poor overall survival despite advanced technology in surgical resection, chemotherapy and radiation. Progression and recurrence are the hinge causes of low survival. Our aim is to explain the concrete mechanism in the proliferation and progression of tumours based on tumour microenvironment (TME). The main purpose is to illustrate the mechanism of proton pump inhibitors (PPIs) in affecting acidity, hypoxia, oxidative stress, inflammatory response and autophagy based on the TME to induce apoptosis and enhance the sensitivity of chemoradiotherapy.

FINDINGS

TME is the main medium for tumour growth and progression. Acidity, hypoxia, inflammatory response, autophagy, angiogenesis and so on are the main causes of tumour progress. PPIs, as a common clinical drug to inhibit gastric acid secretion, have the advantages of fast onset, long action time and small adverse reactions. Nowadays, several kinds of literature highlight the potential of PPIs in inhibiting tumour progression. However, long-term use of PPIs alone also has obvious side effects. Therefore, till now, how to apply PPIs to promote the effect of radio-chemotherapy and find the concrete dose and concentration of combined use are novel challenges.

CONCLUSIONS

PPIs display the potential in enhancing the sensitivity of chemoradiotherapy to defend against glioma based on TME. In the clinic, it is also necessary to explore specific concentrations and dosages in synthetic applications.