Curcumin as a protector for normal cells during bortezomib therapy

Another look at phenolic compounds in cancer therapy the effect of polyphenols on ubiquitin-proteasome system

Inhibitors of the ubiquitin-proteasome system (UPS) have been the object of research interests for many years because of their potential as anti-cancer agents. Research in this field is aimed at improving the specificity and safety of known proteasome inhibitors. Unfortunately, in vitro conditions do not reflect the processes taking place in the human body. Recent reports indicate that the components of human plasma affect the course of many signaling pathways, proteasome activity and the effectiveness of synthetic cytostatic drugs. Therefore, it is believed that the key issue is to determine the effects of components of the human diet, including effects of chemically active polyphenols on the ubiquitin-proteasome system activity in both physiological and pathological (cancerous) states. The following article summarizes the current knowledge on the direct and indirect synergistic and antagonistic effects between polyphenolic compounds present in the human diet and the efficiency of protein degradation via the UPS.

Targeted therapy of intracranial glioma model mice with curcumin nanoliposomes

Background

Glioma is the most aggressive and lethal brain tumor in humans, it comprises about 30 per cent of all brain tumors and central nervous system tumors.

Purpose

The objective of this study was to create novel brain-targeting nanoliposomes to encapsulate curcumin as a promising option for glioma therapy.

Patients and methods

Human glioma cells (U251MG) were used to determine cell uptake efficiency and possible internalization mechanism of the curcumin-loaded nanoliposomes modified by a brain-targeting peptide RDP. In addition, intracranial glioma mice model was prepared by transplantation of U251MG cells into the mice striatum, and then the liposomes were intravenously administered into the glioma-bearing mice to evaluate the anti-glioma activity.

Results

RDP-modified liposomes (RCL) could enter the brain and glioma region, and were internalized by the glioma cells perhaps through acetylcholine receptor-mediated endocytosis pathway. Furthermore, the RCL prolonged the survival time of the glioma-bearing mice from 23 to 33 days, and the inhibition mechanism of the RCL on glioma cell was partly due to cell cycle arrest at the S phase and induction of cell apoptosis.

Conclusion

This study would provide a potential approach for targeted delivery of drug-loaded liposomes for glioma treatment.