dc.description.abstract | The treatment of colorectal cancer (CRC) is confronted with a significant obstacle in the form of multi-drug resistance. This impediment is caused by the capability of various chemotherapy drugs, such as 5-fluorouracil, oxaliplatin, and irinotecan, to become ineffective against CRC. The development of multi-drug resistance is attributed mainly to an important mechanism involving the increased efflux of drugs out of cells by ATP-binding cassette transporters, particularly P-glycoprotein. In this study, we used free and niosomal loaded form of oxaliplatin as a chemotherapy agent in combination with free and niosomal loaded form of curcumin on normal and oxaliplatin-resistant CRC cells and evaluated their effects on survival, apoptosis and cell cycle arrest of these cells. Curcumin was used as a drug-resistance inhibitor agent and its drug-resistance reversion ability was evaluated by the expression level of MRP2 and hTERT.
Material and Method: Firstly, oxaliplatin-resistant SW480 cells were obtained from normal SW480 cell line. Blank niosomal nano particles (NPs), curcumin loaded niosomal (NPs), and Oxaliplatin loaded niosomal (NPs) were fabricated using thin-film hydration method and characterized with SEM, AFM, DLS, and FTIR. A proliferation assay was performed to assess these agent's cytotoxicity on cancer cells. The ability of curcumin and curcumin-loaded niosome in reversion of drug-resistance on SW480 cells was evaluated with real time PCR technique and evaluating the expression level of MDR2.
Findings: Microscopic findings and FT-IR results showed successful drug loading. The results of MTT showed significant cell arrest compared to the control group. Drug toxicity evaluation showed that oxaliplatin loaded in PEGylated niosomal NPs had more toxic effects compared to the pure state in a time- and dose-dependent manner. The results of Real-Time PCR showed that curcumin and oxaliplatin in a free and loaded form in nanoparticles significantly inhibit MRP2, Cyclin D1, BCL-2, and hTERT genes expression and icrease the expression of BAX. The results of the apoptosis test showed that cell death in the presence of oxaliplatin loaded niosomal NPs is of the apoptotic type. Both curcumin and oxaliplatin show cytotoxic effect on cancer cells, although oxaliplatin and curcumin coloaded niosomal NPs has highest cytotoxity. | en_US |