title: Nanoparticle-mediated siRNA delivery assessed in a 3D co-culture model simulating prostate cancer bone metastasis.
abstract: siRNA has emerged as a potential therapeutic for the treatment of prostate cancer but effective delivery remains a major barrier to its clinical application. This study aimed to develop and characterise a 3D in vitro co-culture model to simulate prostate cancer bone metastasis and to assess the ability of the model to investigate nanoparticle-mediated siRNA delivery and gene knockdown. PC3 or LNCaP prostate cancer cells were co-cultured with hFOB 1.19 osteoblast cells in 2D on plastic tissue culture plates and in 3D on collagen scaffolds mimicking the bone microenvironment. To characterise the co-culture model, cell proliferation, enzyme secretion and the utility of two different gene delivery vectors to mediate siRNA uptake and gene knockdown were assessed. Cell proliferation was reduced by∼50% by day 7 in the co-culture system relative to monoculture (PC3 and LNCaP co-cultures, in 2D and 3D) and an enhanced level of MMP9 (a marker of bone metastasis) was secreted into the media (1.2-4-fold increase depending on the co-culture system). A cationic cyclodextrin gene delivery vector proved significantly less toxic in the co-culture system relative to the commercially available vector Lipofectamine 2000(®). In addition, knockdown of both the GAPDH gene (minimum 15%) and RelA subunit of the NF-κB transcription factor (minimum 20%) was achieved in 2D and 3D cell co-cultures. Results indicate that the prostate cancer-osteoblast in vitro co-culture model was more physiologically relevant vs the monoculture. This model has the potential to help improve the design and efficacy of gene delivery formulations, to more accurately predict in vivo performance and, therefore, to reduce the risk of product failure in late-stage clinical development.
authors: Pharmacodelivery Group, School of Pharmacy, University College Cork, Ireland.
authors: Kathleen A
authors: KA
authors: Fitzgerald
authors: Pharmacodelivery Group, School of Pharmacy, University College Cork, Ireland.
authors: Jianfeng
authors: J
authors: Guo
authors: Tissue Engineering Research Group, Anatomy Department, Royal College of Surgeons in Ireland, Dublin, Ireland; Trinity Centre for Bioengineering, Trinity College, Dublin, Ireland; Advanced Materials and Bioengineering Research (AMBER) Centre, RCSI & TCD, Dublin, Ireland.
authors: Rosanne M
authors: RM
authors: Raftery
authors: Tissue Engineering Research Group, Anatomy Department, Royal College of Surgeons in Ireland, Dublin, Ireland; Trinity Centre for Bioengineering, Trinity College, Dublin, Ireland; Advanced Materials and Bioengineering Research (AMBER) Centre, RCSI & TCD, Dublin, Ireland.
authors: Irene Mencía
authors: IM
authors: Castaño
authors: Tissue Engineering Research Group, Anatomy Department, Royal College of Surgeons in Ireland, Dublin, Ireland; Trinity Centre for Bioengineering, Trinity College, Dublin, Ireland; Advanced Materials and Bioengineering Research (AMBER) Centre, RCSI & TCD, Dublin, Ireland.
authors: Caroline M
authors: CM
authors: Curtin
authors: Pharmacodelivery Group, School of Pharmacy, University College Cork, Ireland.
authors: Matt
authors: M
authors: Gooding
authors: Pharmacodelivery Group, School of Pharmacy, University College Cork, Ireland.
authors: Raphael
authors: R
authors: Darcy
authors: Tissue Engineering Research Group, Anatomy Department, Royal College of Surgeons in Ireland, Dublin, Ireland; Trinity Centre for Bioengineering, Trinity College, Dublin, Ireland; Advanced Materials and Bioengineering Research (AMBER) Centre, RCSI & TCD, Dublin, Ireland.
authors: Fergal J
authors: FJ
authors: O' Brien
authors: Pharmacodelivery Group, School of Pharmacy, University College Cork, Ireland. Electronic address: caitriona.odriscoll@ucc.ie.
authors: Caitriona M
authors: CM
authors: O' Driscoll
mesh_terms: D001859:Bone Neoplasms / Q000188:drug therapy / Q000378:metabolism / Q000556:secondary; D049109:Cell Proliferation / Q000187:drug effects / Q000502:physiology; D002470:Cell Survival / Q000187:drug effects / Q000502:physiology; D018920:Coculture Techniques / Q000379:methods; D018014:Gene Transfer Techniques; D006801:Humans; D008297:Male; D053758:Nanoparticles / Q000008:administration & dosage* / Q000378:metabolism; D011471:Prostatic Neoplasms / Q000188:drug therapy / Q000378:metabolism; D034741:RNA, Small Interfering / Q000008:administration & dosage* / Q000378:metabolism; D014407:Tumor Cells, Cultured
chemical_list: D034741:RNA, Small Interfering
keywords: 3D co-culture; Collagen-based scaffolds; Gene delivery; Modified cyclodextrin; Osteoblasts; Prostate cancer cells