Biological roles of filamin a in prostate cancer cells

ABSTRACT Objective This study aims to investigate the association of filamin A with the function and morphology of prostate cancer (PCa) cells, and explore the role of filamin A in the development of PCa, in order to analyze its significance in the evolvement of PCa. Materials and Methods A stably transfected cell line, in which filamin A expression was suppressed by RNA interference, was first established. Then, the effects of the suppression of filamin A gene expression on the biological characteristics of human PCa LNCaP cells were observed through cell morphology, in vitro cell growth curve, soft agar cloning assay, and scratch test. Results A cell line model with a low expression of filamin A was successfully constructed on the basis of LNCaP cells. The morphology of cells transfected with plasmid pSilencer-filamin A was the following: Cells were loosely arranged, had less connection with each other, had fewer tentacles, and presented a fibrous look. The growth rate of LNCap cells was faster than cells transfected with plasmid pSilencer-filamin A (P <0.05). The clones of LNCap cells in the soft agar cloning assay was significantly fewer than that of cells stably transfected with plasmid pSilencer-filamin A (P <0.05). Cells stably transfected with plasmid pSilencer-filamin A presented with a stronger healing and migration ability compared to LNCap cells (healing rate was 32.2% and 12.1%, respectively; P <0.05). Conclusion The expression of the filamin A gene inhibited the malignant development of LNCap cells. Therefore, the filamin A gene may be a tumor suppressor gene.

Delivery of BACE1 siRNA mediated by TARBP-BTP fusion protein reduces b-amyloid deposits in a transgenic mouse model of Alzheimer’s disease

Systemic delivery of nucleic acids to the central nervous system (CNS) is a major challenge for the development of RNAinterference-based therapeutics due to lack of stability, target specificity, non-permeability to the blood–brain barrier (BBB),and lack of suitable carriers. Using a designed bi-functional fusion protein TARBP-BTP in a complex with siRNA, weearlier demonstrated knockdown of target genes in the brain of both AbPP-PS1 (Alzheimer’s disease, AD) and wild-typeC57BL/6 mice. In this report, we further substantiate the approach through an extended use in AbPP-PS1 mice, which upontreatment with seven doses of b-secretase AbPP cleaving Enzyme 1 (BACE1) TARBP-BTP:siRNA, led to target-specificeffect in the mouse brain. Concomitant gene silencing of BACE1, and consequent reduction in plaque load in the cerebralcortex and hippocampus ([60%) in mice treated with TARBP-BTP:siRNA complex, led to improvement in spatial learningand memory. The study validates the efficiency of TARBP-BTP fusion protein as an efficient mediator of RNAi, givingconsiderable scope for future intervention in neurodegenerative disorders through the use of short nucleic acids as genespecific inhibitors.