Green synthesis of ginger-encapsulated zinc oxide nanoparticles: Unveiling their characterization and selective cytotoxicity on MDA-MB 231 breast cancer cells.

Zinc oxide nanoparticles (ZnO-NPs) were synthesized using ginger (Zingiber officinale) extracts in a green synthesis approach and evaluated their in vitro cytotoxicity effect on the MDA-MB 231 breast cancer cell line. The bottom-up approach was employed to develop the green-synthesized ginger-encapsulated ZnO-NPs (GZnO-NPs) without using hazardous substances. The most substantial Fourier-transform infrared absorption peak of the ginger root extract was seen at 1634.24 cm-1. The peak also confirmed the presence of ginger root extract-encapsulated ZnO-NPs at 1556.79, 1471.54, and 1019.83 cm-1. It indicates that the biomolecules found in plant extracts behave as capping agents, aiding in the formation of nanoparticles. The mean particle sizes (PSs) of optimized GZnO-NPs of the ratios 1:2 were found to be 104.01 ± 7.12 nm with a zeta potential of -11.5 ± 1.31 mV. The X-ray diffraction and scanning electron microscope analysis confirmed that the prepared nanoparticles were spherical and crystalline, with PS ranging from 100 to 150 nm. The GZnO-NPs were subjected to MTT assay and cellular migration potential, and it was found that the inhibitory concentration on the MDA-MB 231 (breast) cancer cell line and scratch area showed a dose-dependent efficacy. The successfully green-synthesized GZnO-NPs effectively induced cell death in the MDA-MB 231 cancer cell line. The scratch assay results confirmed that prepared GZnO-NPs inhibited the proliferation and migration of cancerous cells.

Targeting colorectal cancer stem cells using curcumin and curcumin analogues: insights into the mechanism of the therapeutic efficacy.

Colorectal cancer is one of the commonest cancers in the world and it is also a common cause of cancer-related death worldwide. Despite advanced treatment strategies, the disease is rarely cured completely due to recurrence. Evidence shows that this is due to a small population of cells, called cancer stem cells (CSCs), in the tumour mass that have the self-renewal and differentiation potential to give rise to a new tumour population. Many pre-clinical and clinical studies have used curcumin and its analogues as anti-cancer agents in various types of cancer, including colorectal cancer. Intriguingly, curcumin and its analogues have also recently been shown to be effective in lowering tumour recurrence by targeting the CSC population, hence inhibiting tumour growth. In this review, we highlight the efficacy of curcumin and its analogues in targeting colorectal CSC and also the underlying molecular mechanism involved. Curcumin, in the presence or absence of other anti-cancer agents, has been shown to reduce the size of tumour mass and growth in both in vivo and in vitro studies by affecting many intracellular events that are associated with cancer progression and CSC formation. An insight into the molecular mechanism has unraveled the mode of action via which curcumin could affect the key regulators in CSC, importantly; (1) the signaling pathways, including Wnt/ß-catenin, Sonic Hedgehog, Notch and PI3K/Akt/mTOR, (2) microRNA and (3) the epithelial-mesenchymal transition at multiple levels. Therefore, curcumin could play a role as chemosensitiser whereby the colorectal CSCs are now sensitised towards the anti-cancer therapy, therefore, combination therapy using anti-cancer agent with curcumin could be much more effective than treatment using a single cancer agent. This potential treatment modality can be further developed by employing an effective delivery system using a nanotechnology based approach to treat colorectal cancer.