Liposomes co-Loaded with 6-Phosphofructo-2-Kinase/Fructose-2, 6-Biphosphatase 3 (PFKFB3) shRNA Plasmid and Docetaxel for the Treatment of non-small Cell Lung Cancer.

PURPOSE: Non-small cell lung cancer is the leading cause of cancer related deaths globally. Considering the side effects and diminishing chemosensitivity to chemotherapy, novel treatment approaches are sought. Hence, we aim to develop a liposomal co-delivery system of pDNA expressing shRNA against PFKFB3 (pshPFKFB3) and docetaxel (DTX).

METHODS: Cationic DTX liposomes complexed with pshPFKFB3 (PSH-DL) were developed. In vitro cell line studies were performed to evaluate transfection, PFKFB3 mRNA silencing, cytotoxicity, pGP inhibition, and protein markers expression. In vivo efficacy study was performed in A549 xenograft nude mice model.

RESULTS: Cytotoxicity studies showed significantly enhanced anticancer activity of PSH-DL against individual treatment alone confirming the chemoenhancing effect of pshPFKFB3 on DTX activity. Fluorescence microscopy and RT-PCR showed effective transfection and RNAi by pshPFKFB3. pGP inhibition assay and western blotting revealed that PFKFB3 downregulation caused diminution of pGP activity leading to changes in cell cycle (Cdk2), survival (survivin), apoptosis (Bcl2 and cleaved caspase 3) and stress (p-JNK and p-p38) markers so that induces apoptosis by PSH-DL in NSCLC cells. PSH-DL also showed ~3.8-fold reduction in tumor volume in A549 xenograft model which was significantly higher than individual treatments alone.

CONCLUSION: Targeting PFKFB3 through shRNA based RNAi is a promising approach for potentiating activity of DTX in NSCLC.