Trivia Frazier

Curcumin-loaded γ-cyclodextrin liposomal nanoparticles as delivery vehicles for osteosarcoma

UNLABELLED The delivery of curcumin, a broad-spectrum anticancer drug, has been explored in the form of liposomal nanoparticles to treat osteosarcoma (OS). Curcumin is water insoluble and an effective delivery route is through encapsulation in cyclodextrins followed by a second encapsulation in liposomes. Liposomal curcumins potential was evaluated against cancer models of mesenchymal (OS) and epithelial origin (breast cancer). The resulting 2-Hydroxypropyl-γ-cyclodextrin/curcumin - liposome complex shows promising anticancer potential both in vitro and in vivo against KHOS OS cell line and MCF-7 breast cancer cell line. An interesting aspect is that liposomal curcumin initiates the caspase cascade that leads to apoptotic cell death in vitro in comparison with DMSO-curcumin induced autophagic cell death. In addition, the efficiency of the liposomal curcumin formulation was confirmed in vivo using a xenograft OS model. Curcumin-loaded γ-cyclodextrin liposomes indicate significant potential as delivery vehicles for the treatment of cancers of different tissue origin. FROM THE CLINICAL EDITOR Curcumin-loaded γ-cyclodextrin liposomes were demonstrated in vitro to have significant potential as delivery vehicles for the treatment of cancers of mesenchymal and epithelial origin. Differences between mechanisms of cell death were also evaluated.

Human Adipose Tissue-Derived Stromal/Stem Cells Promote Migration and Early Metastasis of Triple Negative Breast Cancer Xenografts

Background Fat grafting is used to restore breast defects after surgical resection of breast tumors. Supplementing fat grafts with adipose tissue-derived stromal/stem cells (ASCs) is proposed to improve the regenerative/restorative ability of the graft and retention. However, long term safety for ASC grafting in proximity of residual breast cancer cells is unknown. The objective of this study was to determine the impact of human ASCs derived from abdominal lipoaspirates of three donors, on a human breast cancer model that exhibits early metastasis. Methodology/Principal Findings Human MDA-MB-231 breast cancer cells represents “triple negative” breast cancer that exhibits early micrometastasis to multiple mouse organs [1]. Human ASCs were derived from abdominal adipose tissue from three healthy female donors. Indirect co-culture of MDA-MB-231 cells with ASCs, as well as direct co-culture demonstrated that ASCs had no effect on MDA-MB-231 growth. Indirect co-culture, and ASC conditioned medium (CM) stimulated migration of MDA-MB-231 cells. ASC/RFP cells from two donors co-injected with MDA-MB-231/GFP cells exhibited a donor effect for stimulation of primary tumor xenografts. Both ASC donors stimulated metastasis. ASC/RFP cells were viable, and integrated with MDA-MB-231/GFP cells in the tumor. Tumors from the co-injection group of one ASC donor exhibited elevated vimentin, matrix metalloproteinase-9 (MMP-9), IL-8, VEGF and microvessel density. The co-injection group exhibited visible metastases to the lung/liver and enlarged spleen not evident in mice injected with MDA-MB-231/GFP alone. Quantitation of the total area of GFP fluorescence and human chromosome 17 DNA in mouse organs, H&E stained paraffin sections and fluorescent microscopy confirmed multi-focal metastases to lung/liver/spleen in the co-injection group without evidence of ASC/RFP cells. Conclusions Human ASCs derived from abdominal lipoaspirates of two donors stimulated metastasis of MDA-MB-231 breast tumor xenografts to multiple mouse organs. MDA-MB-231 tumors co-injected with ASCs from one donor exhibited partial EMT, expression of MMP-9, and increased angiogenesis.

Body mass index affects proliferation and osteogenic differentiation of human subcutaneous adipose tissue-derived stem cells

BackgroundObesity is associated with a higher risk of developing cancer and co-morbidities that are part of the metabolic syndrome. Adipose tissue is recognized as an endocrine organ, as it affects a number of physiological functions, and contains adipose tissue-derived stem cells (ASCs). ASCs can differentiate into cells of multiple lineages, and as such are applicable to tissue engineering and regenerative medicine. Yet the question of whether ASC functionality is affected by the donor’s body mass index (BMI) still exists.ResultsASCs were isolated from patients having different BMIs (BMI-ASCs), within the ranges of 18.5-32.8. It was hypothesized that overweight BMI-ASCs would be more compromised in early adipogenic and osteogenic potential, and ability to form colonies in vitro. BMI was inversely correlated with ASC proliferation and colony forming potential as assessed by CyQUANT proliferation assay (fluorescence- based measurement of cellular DNA content), and colony forming assays. BMI was positively correlated with early time point (day 7) but not later time point (day 15) intracytoplasmic lipid accumulation as assessed by Oil-Red-O staining. Alizarin red staining and RT-PCR for alkaline phosphatase demonstrated that elevated BMI resulted in compromised ASC mineralization of extracellular matrix and decreased alkaline phosphatase mRNA expression.ConclusionsThese data demonstrate that elevated BMI resulted in reduced ASC proliferation, and potentially compromised osteogenic capacity in vitro; thus BMI is an important criterion to consider in selecting ASC donors for clinical applications.

Evolution and future prospects of adipose-derived immunomodulatory cell therapeutics.

Over the past two decades, tissue engineering and regenerative medicine have evolved from what many considered a theoretical science to what is now a clinical reality. Tissue engineering combines biomaterial scaffolds, growth factors and stem or progenitor cells to repair damaged tissues. Adipose tissue, an abundant and easily accessed tissue, is a potential source of stromal/stem cells for regenerative therapeutic applications. Like bone marrow-derived mesenchymal stem cells, adipose-derived stromal/stem cells display both immunomodulatory and immunosuppressive properties. The adipose cells exert these actions, in part, through their secretion of paracrine growth factors. This review highlights recent developments in the isolation, characterization and preclinical application of adipose-derived cells and the challenges facing their translation into clinical practice.

Adipose Stromal Cells Repair Pressure Ulcers in Both Young and Elderly Mice: Potential Role of Adipogenesis in Skin Repair

More than 2.5 million patients in the U.S. require treatment for pressure ulcers annually, and the elderly are at particularly high risk for pressure ulcer development. Current therapy for pressure ulcers consists of conservative medical management for shallow lesions and aggressive debridement and surgery for deeper lesions. The current study uses a murine model to address the hypothesis that adipose‐derived stromal/stem cell (ASC) treatment would accelerate and enhance pressure ulcer repair. The dorsal skin of both young (2 months old [mo]) and old (20 mo) C57BL/6J female mice was sandwiched between external magnets for 12 hours over 2 consecutive days to initiate a pressure ulcer. One day following the induction, mice were injected with ASCs isolated from congenic mice transgenic for the green fluorescent protein under a ubiquitous promoter. Relative to phosphate‐buffered saline‐treated controls, ASC‐treated mice displayed a cell concentration‐dependent acceleration of wound closure, improved epidermal/dermal architecture, increased adipogenesis, and reduced inflammatory cell infiltration. The ASC‐induced improvements occurred in both young and elderly recipients, although the expression profile of angiogenic, immunomodulatory, and reparative mRNAs differed as a function of age. The results are consistent with clinical reports that fat grafting improved skin architecture in thermal injuries; the authors of this published study have invoked ASC‐based mechanisms to account for their clinical outcomes. Thus, the current proof‐of‐principle study sets the stage for clinical translation of autologous and/or allogeneic ASC treatment of pressure ulcers.

Serially Transplanted Nonpericytic CD146− Adipose Stromal/Stem Cells in Silk Bioscaffolds Regenerate Adipose Tissue In Vivo

Progenitors derived from the stromal vascular fraction (SVF) of white adipose tissue (WAT) possess the ability to form clonal populations and differentiate along multiple lineage pathways. However, the literature continues to vacillate between defining adipocyte progenitors as “stromal” or “stem” cells. Recent studies have demonstrated that a nonpericytic subpopulation of adipose stromal cells, which possess the phenotype, CD45−/CD31−/CD146−/CD34+, are mesenchymal, and suggest this may be an endogenous progenitor subpopulation within adipose tissue. We hypothesized that an adipose progenitor could be sorted based on the expression of CD146, CD34, and/or CD29 and when implanted in vivo these cells can persist, proliferate, and regenerate a functional fat pad over serial transplants. SVF cells and culture expanded adipose stromal/stem cells (ASC) ubiquitously expressing the green fluorescent protein transgene (GFP‐Tg) were fractionated by flow cytometry. Both freshly isolated SVF and culture expanded ASC were seeded in three‐dimensional silk scaffolds, implanted subcutaneously in wild‐type hosts, and serially transplanted. Six‐week WAT constructs were removed and evaluated for the presence of GFP‐Tg adipocytes and stem cells. Flow cytometry, quantitative polymerase chain reaction, and confocal microscopy demonstrated GFP‐Tg cell persistence, proliferation, and expansion, respectively. Glycerol secretion and glucose uptake assays revealed GFP‐Tg adipose was metabolically functional. Constructs seeded with GFP‐Tg SVF cells or GFP‐Tg ASC exhibited higher SVF yields from digested tissue, and higher construct weights, compared to nonseeded controls. Constructs derived from CD146− CD34+ ‐enriched GFP‐Tg ASC populations exhibited higher hemoglobin saturation, and higher frequency of GFP‐Tg cells than unsorted or CD29+ GFP‐Tg ASC counterparts. These data demonstrated successful serial transplantation of nonpericytic adipose‐derived progenitors that can reconstitute adipose tissue as a solid organ. These findings have the potential to provide new insights regarding the stem cell identity of adipose progenitor cells. Stem Cells 2016;34:1097–1111

Abstract 4227: Curcumin in cyclodextrin in liposome as a delivery vehicle against osteosarcoma

Proceedings: AACR 102nd Annual Meeting 2011‐‐ Apr 2‐6, 2011; Orlando, FL The delivery of curcumin, a broad spectrum anticancer drug, has been explored in the form of liposomal nanoparticles to treat osteosarcoma. Osteosarcoma (OS) accounts for approximately 20% of all bone cancers and it develops during the period of rapid growth in adolescence. Anti-cancer potential of curcumin has not been fully explored in the form of nanoformulations against OS. The drug is water insoluble and an effective delivery route is through encapsulation in cyclodextrins followed by a second encapsulation in liposomes. Liposomal curcumins potential evaluated against OS and breast cancer. The resulting 2-Hydroxypropyl-gamma-cyclodextrin/curcumin-liposome complex shows promising anticancer potential against cancer of mesenchymal and epithelial origin when tested against KHOS and MCF-7 cell lines with IC50 value of 5.4 and 10.2 µg/ml respectively. The anticancer potential of curcumin in the form of DCL (drug-in-cyclodextrin-in-liposome) preparation has been explored first time for OS. DMSO-curcumin (free drug) induced autophagic cell death in KHOS whereas liposomal curcumin initiates the caspase cascade that leads to apoptotic cell death in vitro and in vivo also. The in vivo study was performed using human osteosarcoma xenograft model in mice. Interestingly, liposomal curcumin was less toxic on normal cells. In this study, the objective to cause cancer cell death by apoptosis and not by autophagy was achieved through liposomal curcumin formulations alone. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4227. doi:10.1158/1538-7445.AM2011-4227

Comparative proteomic analyses of human adipose extracellular matrices decellularized using alternative procedures: COMPARATIVE PROTEOMIC ANALYSES OF HUMAN ADIPOSE ECM

Decellularized human adipose tissue has potential clinical utility as a processed biological scaffold for soft tissue cosmesis, grafting, and reconstruction. Adipose tissue decellularization has been accomplished using enzymatic-, detergent-, and/or solvent-based methods. To examine the hypothesis that distinct decellularization processes may yield scaffolds with differing compositions, the current study employed mass spectrometry to compare the proteomes of human adipose-derived matrices generated through three independent methods combining enzymatic-, detergent-, and/or solvent-based steps. In addition to protein content, bioscaffolds were evaluated for deoxyribose nucleic acid depletion, extracellular matrix composition, and physical structure using optical density, histochemical staining, and scanning electron microscopy. Mass spectrometry based proteomic analyses identified 25 proteins (having at least two peptide sequences detected) in the scaffolds generated with an enzymatic approach, 143 with the detergent approach, and 102 with the solvent approach, as compared to 155 detected in unprocessed native human fat. Immunohistochemical detection confirmed the presence of the structural proteins actin, collagen type VI, fibrillin, laminin, and vimentin. Subsequent in vivo analysis of the predominantly enzymatic- and detergent-based decellularized scaffolds following subcutaneous implantation in GFP+ transgenic mice demonstrated that the matrices generated with both approaches supported the ingrowth of host-derived adipocyte progenitors and vasculature in a time dependent manner. Together, these results determine that decellularization methods influence the protein composition of adipose tissue-derived bioscaffolds.