CHITOSAN NANOPARTICLES MEDIATED DELIVERY OF MIR-106B-5P TO BREAST CANCER CELL LINES MCF-7 AND T47D

Objective: The development of nanomedicine, such as miRNA transfection to cancer cells,has widely gained interest in the past decade. Unfortunately, miRNA tends to decay easily by the cellular enzymatic process and requires a carrier. As a cationic biopolymer, chitosan is widely known as a non-viral vector. However, research about chitosan as a miRNA delivery system remains limited. This study aimed to investigate the effect and characters of synthetic miRNA loaded chitosan nanoparticles on breast cancer cell lines. Methods: To obtain the nanocomplex, chitosan-antimiR-106b-5p was formulated using natriumtripolyphosphate through ionic gelation methods. The nanochitosan formula was characterized by using gel electrophoresis; Nano Quant for encapsulation of entrapment quantification; morphology appearance as viewed by Scanning Electron Microscope (SEM), nanochitosan size analysis; in vitro analysis using MCF-7 and T47D breast cancer cell lines; in silico prediction of possible gene target; polymerase chain reaction analysis and gel electrophoresis for E2F1/GAPDH expression. Results: The efficiency entrapment value was 96.7%, particle size analysis was 458±11.79 nm, and polydispersity index (PDI) was 0.65±0.07, with spherical morphology as viewed in SEM. There was no significant difference between the nanochitosan supplemented group and the control group in MCF-7 cells (p=0.067). However, the ratio of E2F1 to GAPDH was significantly lower than the control group after nanochitosan antimiR-106b-5p was loaded at concentration 140 nmol (p=0.022) and 35 nmol (p=0.016). Conclusion: Our nanochitosan formula is non-toxic to use in MCF-7 cell lines. Most importantly, as the formula was conjugated to synthetic antimiR-106b-5p, the E2F1 expression decreased.