Formulation and characterization of cisplatin-loaded hydroxyl functionalized single-walled carbon nanotubes for targeting gastric cancer stem cells

Chemotherapy is the most commonly used therapeutic method for treating many malignancies including gastric cancer. Due to their non-specific and non-targeted drug delivery, it causes resistance leading to cancer progression, relapse, and metastasis of cancer. To overcome this problem we carried out a study aimed to develop a new cisplatin (Cisp) loaded hydroxyl functionalized single-walled carbon nanotube (OH-SWCNT) nanocarrier system to selectively eliminate gastric cancer stem cells. To our understanding, this is the first study of the non-covalent interaction of cisplatin loaded on the surface of hydroxyl-functionalized single-walled carbon nanotubes by ultrasonication. The physical and morphological characterization was carried out by UV-Vis, FTIR spectroscopy, and TEM. A sustained and controlled release of cisp from OH-SWCNT at all three pHs 3.5, 5.5, and 7.4 was observed. Gastric cancer stem cells were isolated from primary cells and were identified by using CD133+ and CD44+ specific markers. Cisplatin-loaded OH-SWCNT nanocarrier was capable of limiting the self-renewal capacity of both CD133+ and CD44+ populations and also decreasing the number of tumorspheres in gastric CSCs. The cell viability percent of AGS cells was 20% at 250 μg/ml concentration. The IC50 value was less than 50% mol/L at both 200 μg/ml and 250 μg/ml of cisplatin-loaded OH-SWCNT. Our findings suggest that cisplatin-loaded OH-SWCNT nanocarrier complexes could target gastric CSCs and also could provide a potential strategy for selectively targeting and efficiently eliminating gastric CSCs. This could be a promising approach to prevent gastric cancer recurrence and metastasis and also improve gastric cancer therapy.

Effect of selenium enriched wheat substrate on the nutritional and antioxidant properties of Pleurotus spp

The study demonstrated that cultivation of Pleurotus ostreatus var. florida, Pleurotus eryngii, Pleurotus cornucopiae and Pleurotus djamor on selenium enriched substrate did not significantly affect biological efficiency (%), but total soluble protein content, total phenolic content, flavonoid content and free radical scavenging activity (%) were found to be significantly improved in Se enriched fruit bodies as compared to the control. Elemental analysis of the Se biofortified Pleurotus mushrooms through SEM-EDS showed signals characteristic for selenium on surface of P. ostreatus. var. florida and P. djamor confirming that selenium was incorporated into the cell wall of these fruiting bodies. The Se content was found to be 22.34 μg g−1 dw in Se enriched wheat straw and 0.059 μg g−1 dw in respective non-enriched wheat straw. Se contents of Se-enriched fruit bodies were found to be higher compared to non-enriched Pleurotus spp. FT-IR spectra of proteins from Pleurotus spp. indicated an increase in the flexibility, unfolding, hydrophilicity of the proteins upon Se supplementation.