Isolation and characterizations of multidrug-resistant human cancer cells by a biodegradable nano-sensor.

Multidrug resistance (MDR) remains a significant challenge in cancer therapy, with inherent and acquired resistance distinct. While conventional drug selection processes enable the isolation of cancer cells with acquired multidrug resistance, identifying cancer cells with inherent drug resistance remains challenging. Herein, we proposed a molecular beacon (MB)-based strategy to identify and isolate the inherent MDR cancer cells. A lipid/PLGA core-shell nanoparticulate system (DNCP) was designed to deliver MB for intracellular MDR1 mRNA imaging. DNCP-MB - possess a surface potential of -8 mV and a size of 150 nm - demonstrated effective delivery of MB, remarkable selectivity towards the selected intracellular mRNA targets, and low cytotoxicity. Following DNCP transfection, fluorescence-activated cell sorting (FACS) was employed to differentiate MCF-7 cells into two distinct sub-populations: the Top 10 cells with a high level of MDR gene expression and the Bottom 10 cells with a low level of MDR gene expression, which represent inherent drug-resistant and non-drug-resistant cells, respectively. Intriguingly, we observed a positive correlation between elevated MDR1 mRNA expression and increased migration, enhanced proliferation rate, and tighter spheroid formation. Moreover, we conducted RNA sequencing analysis on the Top 10, Bottom 10, and MCF-7/ADR cells. The findings revealed a notable disparity in the gene ontology enrichment analysis of differentially expressed genes between the Top 10 and Bottom 10 cells when compared to the Bottom 10 and MCF-7/ADR cells. This novel approach provides a promising avenue for isolating inherent drug-resistant cells and holds significant potential in unraveling the mechanisms underlying inherent drug resistance.

3D-Bioprinted GelMA Scaffold with ASCs and HUVECs for Engineering Vascularized Adipose Tissue.

The purpose of tissue engineering is to reconstruct parts of injured tissues and to resolve the shortage of organ donations. However, the main concern is the limited size of engineered tissue due to insufficient oxygen and nutrition distribution in large three-dimensional (3D) tissue constructs. To provide better support for cells inside the scaffolds, the vascularization of blood vessels within the scaffold could be a solution. This study compared the effects of different culturing systems using human adipose tissue-derived stem/stromal cells (ASCs), human umbilical vein endothelial cells (HUVECs), and coculture of ASCs and HUVECs in 3D-bioprinted gelatin methacrylate (GelMA) hydrogel constructs. The in vitro results showed that the number of live cells was highest in the coculture of ASCs and HUVECs in the GelMA hydrogel after culturing for 21 days. Additionally, the tubular structure was the most abundant in the GelMA hydrogel, containing both ASCs and HUVECs. In the in vivo test, blood vessels were present in both the HUVECs and the coculture of ASCs and HUVECs hydrogels implanted in mice. However, the blood vessel density was the highest in the HUVEC and ASC coculture groups. These findings indicate that the 3D-bioprinted GelMA hydrogel coculture system could be a promising biomaterial for large tissue engineering applications.

Programmed T cells infiltration into lung metastases with harnessing dendritic cells in cancer immunotherapies by catalytic antigen-capture sponges.

T lymphocytes served as immune surveillance to suppress metastases by physically interacting with cancer cells. Whereas tumor immune privilege and heterogeneity protect immune attack, it limits immune cell infiltration into tumors, especially in invasive metastatic clusters. Here, a catalytic antigen-capture sponge (CAS) containing the catechol-functionalized copper-based metal organic framework (MOF) and chloroquine (CQ) for programming T cells infiltration is reported. The intravenously injected CAS accumulates at the tumor via the folic acid-mediated target and margination effect. In metastases, Fenton-like reaction induced by copper ions of CAS disrupts the intracellular redox potential, i.e., chemodynamic therapy (CDT), thereby reducing glutathione (GSH) levels. Furthermore, CQ helps inhibit autophagy by inducing lysosomal deacidification during CDT. This process leads to the breakdown of self-defense mechanisms, which exacerbates cytotoxicity. The therapies promote the liberation of tumor-associated antigens, such as neoantigens and damage-associated molecular patterns (DAMPs). Subsequently, the catechol groups present on CAS perform as antigen reservoirs and transport the autologous tumor-associated antigens to dendritic cells, resulting in prolonged immune activation. The CAS, which is capable of forming in-situ, serves as an antigen reservoir in CDT-mediated lung metastasis and leads to the accumulation of immune cells in metastatic clusters, thus hindering metastatic tumors.

Programmed antigen capture-harnessed dendritic cells by margination-hitchhiking lung delivery.

Adoptive T cells and immunotherapy suppress the most destructive metastatic tumors and prevent tumor recurrence by inducing T lymphocytes. However, the heterogeneity and immune privilege of invasive metastatic clusters often reduce immune cell infiltration and therapeutic efficacy. Here, the red blood cells (RBC)-hitchhiking mediated lung metastasis delivery of multi-grained iron oxide nanostructures (MIO) programming the antigen capture, dendritic cell harnessing, and T cell recruitment is developed. MIO is assembled to the surface of RBCs by osmotic shock-mediated fusion, and reversible interactions enable the transfer of MIO to pulmonary capillary endothelial cells by intravenous injection by squeezing RBCs at the pulmonary microvessels. RBC-hitchhiking delivery revealed that >65% of MIOs co-localized in tumors rather than normal tissues. In alternating magnetic field (AMF)-mediated magnetic lysis, MIO leads to the release of tumor-associated antigens, namely neoantigens and damage-associated molecular patterns. It also acted as an antigen capture agent-harnessed dendritic cells delivers these antigens to lymph nodes. By utilizing site-specific targeting, erythrocyte hitchhiker-mediated delivery of MIO to lung metastases improves survival and immune responses in mice with metastatic lung tumors.

Arginine-tocopherol bioconjugated lipid vesicles for selective pTRAIL delivery and subsequent apoptosis induction in glioblastoma cells.

The incorporation of specific therapeutic gene into glioblastoma offers potent therapeutic strategy to treat the disease. Non-viral gene delivery vectors are of particular interest due to their tuneable transfection efficiency and easy scale-up. Herein, we demonstrate successful delivery of plasmid encoding tumor necrosis factor (TNF)-related apoptosis-inducing ligand (pTRAIL) using arginine-conjugated tocopherol lipid (AT) nanovesicles into glioblastoma cell lines. Another cationic lipid, glycine-conjugated tocopherol lipid (GT) having glycine in the head group region is also synthesized as a control lipid. Both lipid-derived liposomes effectively condensed the pDNA and the corresponding biomacromolecular assemblies (lipoplexes) are efficiently transfected into different cell lines. AT-based liposomes exhibit higher transfection efficacy in various cell lines, particularly selective in glioma cell lines. At an optimized N/P ratio, both the liposomal formulations show low cytotoxicity. AT-based lipoplexes have superior cellular uptake in U87 than the control lipid GT. The expression of TRAIL protein regulated death receptor and apoptosis signaling pathway is assayed by western blot using transfection of AT-based/pTRAIL into U87 cell lines. Induction of apoptosis in U87 cells exposed to AT-based/pTRAIL plasmid is evaluated by MTT assay as well as Annexin V-propidium iodide dual-staining assay. All results indicate that the developed AT-based/pTRAIL system offers a potentially safe and efficient therapeutic strategy for glioblastoma gene therapy.

Magnetic nanocomplexes for gene delivery applications.

Gene delivery is an indispensable technique for various biomedical applications such as gene therapy, stem cell engineering and gene editing. Recently, magnetic nanoparticles (MNPs) have received increasing attention for their use in promoting gene delivery efficiency. Under magnetic attraction, gene delivery efficiency using viral or nonviral gene carriers could be universally enhanced. Besides, magnetic nanoparticles could be utilized in magnetic resonance imaging or magnetic hyperthermia therapy, providing extra theranostic opportunities. In this review, recent research integrating MNPs with a viral or nonviral gene vector is summarized from both technical and application perspectives. Applications of MNPs in cutting-edge research technologies, such as biomimetic cell membrane nano-gene carriers, exosome-based gene delivery, cell-based drug delivery systems or CRISPR/Cas9 gene editing, are also discussed.

Stem Cell-Based Delivery of Gold/Chlorin e6 Nanocomplexes for Combined Photothermal and Photodynamic Therapy.

Combining photothermal and photodynamic modalities has shown encouraging therapeutic efficacy against various malignant cancers. Developing a delivery method for targeting and penetrating tumors is still a major focus for advancing this therapeutic approach. Herein, we report a novel strategy involving the utilization of stem cells as a live carrier to codeliver photothermal and photodynamic agents for cancer therapy. To this end, a novel gold nanorod (AuNR)-PEG-PEI (APP)/chlorin e6 (Ce6)-loaded adipose-derived stem cell (ADSC) system is proposed in which AuNRs and Ce6 act as the photothermal and photodynamic agents, respectively. To integrate with stem cells, the APP/Ce6 nanocomplexes exhibit advantages of low drug leakage, low cytotoxicity, efficient cellular uptake, and redox-responsive release. After loading of APP/Ce6 nanocomplexes, the ADSCs still maintained good tumor tropism and were capable of penetrating into the tumor spheroids. The photothermal effect induced by exposure to near-infrared light irradiation at 808 nm promoted the release of Ce6 from the stem cells into the surroundings and hence increased its availability to treat cancer cells. APP/Ce6-loaded ADSCs exerted effective dose-dependent in vitro anticancer activities via anticipated photothermal and photodynamic effects. In a murine CT26 colon cancer model, APP/Ce6 delivered by ADSCs resulted in superior tumor suppression compared to other delivery strategies. It was also noted that in vivo applications of APP/Ce6-loaded ADSCs did not induce noticeable detrimental effects on normal tissues/organs.

A preliminary study of Parkinson's gene therapy via sono-magnetic sensing gene vector for conquering extra/intracellular barriers in mice.

BACKGROUND: Non-virus genetic treatment for Parkinson's disease (PD) via plasmid glial cell-line derived neurotrophic factor (pGDNF) has shown potential for repairing damaged dopaminergic neurons. However, development of this gene therapy is largely hampered by the insufficient transfection efficiency as a result of the cell membrane, lysosome, and cytoskeleton meshwork. METHODS: In this study, we propose the use of polyethylenimine (PEI)-superparamagnetic iron oxide-plasmid DNA (pDNA)-loaded microbubbles (PSp-MBs) in conjunction with focused ultrasound (FUS) and two-step magnetic navigation to provide cavitation, proton sponge effect and magnetic effects to increase the efficiency of gene delivery. RESULTS: The gene transfection rate in the proposed system was 2.2-fold higher than that of the commercial agent (TransIT®-LT1). The transfection rate could be boosted ∼11%, ∼10%, and 6% by cavitation-magnetic hybrid enhanced cell membrane permeabilization, proton sponge effect, and magnetic-assisted cytoskeleton-reorganization, respectively. In vivo data suggested that effective gene delivery with this system results in a 3.2-fold increase in recovery of dopaminergic neurons and a 3.9-fold improvement in the motor behavior when compared to untreated genetic PD mice. CONCLUSIONS: We proposed that this novel FUS-magnetic hybrid gene delivery platform could be integrated with a variety of therapeutic genes for treating neurodegenerative diseases in the future.

Ultrasonic Transdermal Delivery System with Acid-Base Neutralization-Generated CO2 Microbubble Cavitation.

Transdermal delivery systems provide a convenient noninvasive approach for drug administration through the skin, and they have been widely developed for in-home health care. The stratum corneum of the skin surface limits drug penetration, but ultrasound (US)-stimulated microbubble (MB) cavitation can enhance skin permeability to promote transdermal drug penetration. However, the specific materials and complex fabrication of MBs influence the scope of application in transdermal delivery systems. Hence, we studied the mixture of citric acid and NaHCO3 agents to generate shell-free CO2-MBs by acid-base neutralization effect. The generation rate of CO2-MBs was 36.3 ± 10 MBs/s and the mean size was 110 ± 14 µm under US sonication (3.1 MHz, 0.5 W/cm2, 50% duty cycle, 1 min). The penetration of Evans blue and FITC-conjugated hyaluronic acid in rat abdominal skin by CO2-MB cavitation improved 2.4 ± 0.3 and 2.1 ± 0.1 fold, respectively. The penetration depth of Evans blue (27.1 ± 5.1 µm) reached the epidermal layer, providing the potential for inducing transcutaneous immunization. Therefore, we proposed a simple and self-operating ultrasonic transdermal delivery system with CO2-MB cavitation to improve drug penetration for in-home health care development.

Adaptable Microporous Hydrogels of Propagating NGF-Gradient by Injectable Building Blocks for Accelerated Axonal Outgrowth.

Injectable hydrogels in regeneration medicine can potentially mimic hierarchical natural living tissue and fill complexly shaped defects with minimally invasive implantation procedures. To achieve this goal, however, the versatile hydrogels that usually possess the nonporous structure and uncontrollable spatial agent release must overcome the difficulties in low cell-penetrative rates of tissue regeneration. In this study, an adaptable microporous hydrogel (AMH) composed of microsized building blocks with opposite charges serves as an injectable matrix with interconnected pores and propagates gradient growth factor for spontaneous assembly into a complex shape in real time. By embedding gradient concentrations of growth factors into the building blocks, the propagated gradient of the nerve growth factor, integrated to the cell-penetrative connected pores constructed by the building blocks in the nerve conduit, effectively promotes cell migration and induces dramatic bridging effects on peripheral nerve defects, achieving axon outgrowth of up to 4.7 mm and twofold axon fiber intensity in 4 days in vivo. Such AMHs with intrinsic properties of tunable mechanical properties, gradient propagation of biocues and effective induction of cell migration are potentially able to overcome the limitations of hydrogel-mediated tissue regeneration in general and can possibly be used in clinical applications.

Magnetic ternary nanohybrids for nonviral gene delivery of stem cells and applications on cancer therapy.

Cancer toxic agent-expressing mesenchymal stem cells (MSCs), which possess inherent tumor migration and penetration capabilities, have received increasing attention in cancer therapy. To ensure that this approach is successful, safe and efficient gene delivery methods for stem cell engineering must be developed. Methods: In this study, a magnetic ternary nanohybrid (MTN) system comprising biodegradable cationic materials, nucleic acids, and hyaluronic acid-decorated superparamagnetic iron oxide nanoparticles was proposed to construct stem cells expressing the tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) via magnetic force and receptor dual targeting. Results: The CD44/magnetic force-mediated enhanced cellular uptake of MTNs by human mesenchymal cells (hMSCs) was confirmed in vitro. Highly efficient transfection was attained using MTNs without having any detrimental effect on the tumor migration and penetration capabilities of hMSCs. TRAIL expressed by the MTN-transfected hMSCs displayed strong anticancer effects through the activation of caspase-3 apoptotic signaling. The MTN-transfected hMSCs can be clearly imaged using magnetic resonance imaging techniques in vivo. In an orthotopic xenograft cancer model, MTN-transfected TRAIL-expressing hMSCs significantly suppressed the progression of human glioma (U87MG) and prolonged the survival of the animal. Conclusions: These findings suggest the considerable potential of utilizing MTNs for effectively constructing tumor toxic agent-expressing stem cells for treating malignant cancers.

Analysis of the Frequency Shift versus Force Gradient of a Dynamic AFM Quartz Tuning Fork Subject to Lennard-Jones Potential Force.

A self-sensing and self-actuating quartz tuning fork (QTF) can be used to obtain its frequency shift as function of the tip-sample distance. Once the function of the frequency shift versus force gradient is acquired, the combination of these two functions results in the relationship between the force gradient and the tip-sample distance. Integrating the force gradient once and twice elucidates the values of the interaction force and the interatomic potential, respectively. However, getting the frequency shift as a function of the force gradient requires a physical model which can describe the equations of motion properly. Most papers have adopted the single harmonic oscillator model, but encountered the problem of determining the spring constant. Their methods of finding the spring constant are very controversial in the research community and full of discrepancies. By circumventing the determination of the spring constant, we propose a method which models the prongs and proof mass as elastic bodies. Through the use of Hamilton's principle, we can obtain the equations of motion of the QTF, which is subject to Lennard-Jones potential force. Solving these equations of motion analytically, we get the relationship between the frequency shift and force gradient.

Gold nanorod-encapsulated biodegradable polymeric matrix for combined photothermal and chemo-cancer therapy.

PURPOSE: A biocompatible nanocomplex system co-encapsulated with gold nanorods (AuNRs) and doxorubicin (DOX) was investigated for its potentials on the combined photothermal- and chemotherapy. MATERIALS AND METHODS: Hydrophobic AuNRs were synthesized by the hexadecyltrimethyl-ammonium bromide (CTAB)-mediated seed growth method, and then, they received two-step surface modifications of polyethylene glycol (PEG) and dodecane. The AuNR/DOX/poly(lactic-co-glycolic acid) (PLGA) nanocomplexes were prepared by emulsifying DOX, AuNR, and PLGA into aqueous polyvinyl alcohol solution by sonication. Human serum albumin (HSA) was used to coat the nanocomplexes to afford HSA/AuNR/DOX-PLGA (HADP). Size and surface potential of the HADP nanocomplexes were determined by using a Zetasizer. Cytotoxicity and cellular uptake of the HADP were analyzed by using MTT assay and flow cytometry, respectively. In vitro anticancer effects of the HADP were studied on various cancer cell lines. To assess the therapeutic efficacy, CT26 tumor-bearing mice were intravenously administered with HADP nanocomplexes and laser treatments, followed by monitoring of the tumor growth and body weight. RESULTS: Size and surface potential of the HADP nanocomplexes were 245.8 nm and -8.6 mV, respectively. Strong photothermal effects were verified on the AuNR-loaded PLGA nanoparticles (NPs) in vitro. Rapid and repeated drug release from the HADP nanocomplexes was successfully achieved by near-infrared (NIR) irradiations. HSA significantly promoted cellular uptake of the HADP nanocomplexes to murine colon cancer cells as demonstrated by cell imaging and flow cytometric studies. By combining photothermal and chemotherapy, the HADP nanocomplexes exhibited strong synergistic anticancer effects in vitro and in vivo. CONCLUSION: An NIR-triggered drug release system by encapsulating hydrophobic AuNR and DOX inside the PLGA NPs has been successfully prepared in this study. The HADP NPs show promising combined photothermal- and chemotherapeutic effects without inducing undesired side effects on a murine colon cancer animal model.

Evaluation of Injectable Chitosan-based Co-cross-linking Hydrogel for Local Delivery of 188Re-LIPO-DOX to Breast-tumor-bearing Mouse Model.

BACKGROUND/AIM: An injectable chitosan-based co-cross-linking thermosensitive hydrogel combining 188Re- and doxorubicin-encapsulated liposomes (C/GP/GE/188Re-LIPO-DOX) was developed for the prevention of locoregional recurrence after mastectomy. MATERIALS AND METHODS: The hydrogel properties, in vitro drug release characteristics, and in vivo scintigraphy imaging attributes were investigated. RESULTS: The gelation time of the hydrogels can be controlled to be within 5 min. Results from Fourier-transform infrared spectroscopy, scanning electron microscopy, and dynamic mechanical analysis showed that a covalent cross-linking reaction between chitosan and genipin occurred and that the hydrogel's mechanical strength and chemical stability were improved. In vitro drug release studies showed that the hydrogel can prolong the release of doxorubicin by several weeks (51.5%±5.3% at 21 days). In addition, in vivo scintigraphy results suggested high retention rates (43.1%±1.0% at 48 h) of the radiopharmaceutical compound at the tumor injection site. CONCLUSION: The preliminary results indicated that the C/GP/GE/188Re-LIPO-DOX radiopharmaceutical hydrogel is a potential candidate for further in vivo therapeutic evaluation.

Intrahepatic hepatitis B virus large surface antigen induces hepatocyte hyperploidy via failure of cytokinesis.

Hepatitis B virus (HBV) is an aetiological factor for liver cirrhosis and hepatocellular carcinoma (HCC). Despite current antiviral therapies that successfully reduce the viral load in patients with chronic hepatitis B, persistent hepatitis B surface antigen (HBsAg) remains a risk factor for HCC. To explore whether intrahepatic viral antigens contribute directly to hepatocarcinogenesis, we monitored the mitotic progression of HBV-positive cells. Cytokinesis failure was increased in HBV-positive HepG2.2.15 and 1.3ES2 cells, as well as in HuH-7 cells transfected with a wild-type or X-deficient HBV construct, but not in cells transfected with an HBsAg-deficient construct. We show that expression of viral large surface antigen (LHBS) was sufficient to induce cytokinesis failure of immortalized hepatocytes. Premitotic defects with DNA damage and G2 /M checkpoint attenuation preceded cytokinesis in LHBS-positive cells, and ultimately resulted in hyperploidy. Inhibition of polo-like kinase-1 (Plk1) not only restored the G2 /M checkpoint in these cells, but also suppressed LHBS-mediated in vivo tumourigenesis. Finally, a positive correlation between intrahepatic LHBS expression and hepatocyte hyperploidy was detected in >70% of patients with chronic hepatitis B. We conclude that HBV LHBS provokes hyperploidy by inducing DNA damage and upregulation of Plk1; the former results in atypical chromatin structures, and the latter attenuates the function of the G2 /M DNA damage checkpoint. Our data uncover a mechanism by which genomic integrity of hepatocytes is disrupted by viral LHBS. These findings highlight the role of intrahepatic surface antigen as an oncogenic risk factor in the development of HCC. Copyright © 2018 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Multifunctional PEGylated Albumin/IR780/Iron Oxide Nanocomplexes for Cancer Photothermal Therapy and MR Imaging.

A multifunctional albumin/superparamagnetic iron oxide nanoparticle (SPIO) nanocomplex system to deliver IR780, a photothermal agent, for cancer theranostic applications was proposed in this study. Single emulsion method was utilized to fabricate the human albumin/IR780/SPIO (HISP) nanocomplexes with a hydrophobic core (SPIO and IR780) and a hydrophilic shell (human serum albumin (HSA) and poly (ethylene glycol) (PEG)). Effects of PEGylation on the size and surface potential of nanocomplexes were analyzed. Nanospheres containing uniformly dispersed SPIO was observed using Transmission Electron Microscopy (TEM) imaging. As a potential magnetic resonance (MR) imaging agent, the HISP displayed dose-dependent T2-weighted imaging contrast (R2 = 81.6 mM-1s-1). Good colloidal stability was verified from the nanocomplexes under difference circumstances. The nanocomplexes were taken up by cancer cells efficiently and led to significant photothermal-mediated cancer cell death upon short-term near infrared (NIR) irradiation in vitro. Via intravenous injection, PEG-HISP can efficiently deliver IR780 to tumor sites and showed strong photothermal effect compared to free drug on the mice model. Significant tumor suppression by the photothermal treatments using PEG-HISP was demonstrated from the mice CT26 xenograft model. Good safety profile of the PEG-HISP was confirmed from histological examination and liver functional analysis. Taken together, the results suggest that PEG-HISP is a safe and robust nano-theranostic platform for advanced anti-cancer treatment.

Tumortropic adipose-derived stem cells carrying smart nanotherapeutics for targeted delivery and dual-modality therapy of orthotopic glioblastoma.

Chemotherapy is typically used to treat malignant brain tumors, especially for the tumors in surgically inaccessible areas. However, owing to the existence of blood-brain barrier (BBB), the tumor accumulation and therapeutic efficacy of clinical therapeutics is still of great concerns. To this end, we present herein a prominent therapeutic strategy adopting adipose-derived stem cells (ADSCs) capable of carrying nanotherapeutic payloads selectively toward brain tumors for thermo/chemotherapy. The nanoparticle (NP) payload was obtained from co-assembly of poly(γ-glutamic acid-co-distearyl γ-glutamate) with poly(lactic-co-glycolic acid), paclitaxel (PTX), and oleic acid-coated superparamagnetic iron oxide NPs in aqueous solution. The particle size and drug loading content were ca 110nm and 8.4wt%, respectively. After being engulfed by ADSCs, the nanotherapeutics was found rather harmless to cellular hosts at a PTX concentration of 30µM over 48h in the absence of pertinent stimulus. Nevertheless, the ADSC-based approach combined with high frequency magnetic field exhibits a sound therapeutic performance with a 4-fold increase in therapeutic index on brain astrocytoma (ALTS1C1)-bearing mice (C57BL/6J) as compared to the typical chemotherapy using a current first-line chemodrug, temozolomide. Immunohistochemical examination of brain tumor sections confirms the successful cellular transport and pronounced cytotoxic action of therapeutics against tumor cells in vivo. This work demonstrates the promise of ADSC-mediated chemo/thermal therapy against brain tumors.

Near-IR-Absorbing Gold Nanoframes with Enhanced Physiological Stability and Improved Biocompatibility for In Vivo Biomedical Applications.

This paper describes the synthesis of near-infrared (NIR)-absorbing gold nanoframes (GNFs) and a systematic study comparing their physiological stability and biocompatibility with those of hollow Au-Ag nanoshells (GNSs), which have been used widely as photothermal agents in biomedical applications because of their localized surface plasmon resonance (LSPR) in the NIR region. The GNFs were synthesized in three steps: galvanic replacement, Au deposition, and Ag dealloying, using silver nanospheres (SNP) as the starting material. The morphology and optical properties of the GNFs were dependent on the thickness of the Au coating layer and the degree of Ag dealloying. The optimal GNF exhibited a robust spherical skeleton composed of a few thick rims, but preserved the distinctive LSPR absorbance in the NIR region-even when the Ag content within the skeleton was only 10 wt %, 4-fold lower than that of the GNSs. These GNFs displayed an attractive photothermal conversion ability and great photothermal stability, and could efficiently kill 4T1 cancer cells through light-induced heating. Moreover, the GNFs preserved their morphology and optical properties after incubation in biological media (e.g., saline, serum), whereas the GNSs were unstable under the same conditions because of rapid dissolution of the considerable silver content with the shell. Furthermore, the GNFs had good biocompatibility with normal cells (e.g., NIH-3T3 and hepatocytes; cell viability for both cells: >90%), whereas the GNSs exhibited significant dose-dependent cytotoxicity (e.g., cell viability for hepatocytes at 1.14 nM: ca. 11%), accompanied by the induction of reactive oxygen species. Finally, the GNFs displayed good biocompatibility and biosafety in an in vivo mouse model; in contrast, the accumulation of GNSs caused liver injury and inflammation. Our results suggest that GNFs have great potential to serve as stable, biocompatible NIR-light absorbers for in vivo applications, including cancer detection and combination therapy.

MMP-13 is involved in oral cancer cell metastasis.

The oral cancer cell line OC3-I5 with a highly invasive ability was selected and derived from an established OSCC line OC3. In this study, we demonstrated that matrix metalloproteinases protein MMP-13 was up-regulated in OC3-I5 than in OC3 cells. We also observed that expression of epithelial-mesenchymal transition (EMT) markers including Twist, p-Src, Snail1, SIP1, JAM-A, and vinculin were increased in OC3-I5 compared to OC3 cells, whereas E-cadherin expression was decreased in the OC3-I5 cells. Using siMMP-13 knockdown techniques, we showed that siMMP-13 not only reduced the invasion and migration, but also the adhesion abilities of oral cancer cells. In support of the role of MMP-13 in metastasis, we used MMP-13 expressing plasmid-transfected 293T cells to enhance MMP-13 expression in the OC3 cells, transplanting the MMP-13 over expressing OC3 cells into nude mice led to enhanced lung metastasis. In summary, our findings show that MMP-13 promotes invasion and metastasis in oral cancer cells, suggesting altered expression of MMP-13 may be utilized to impede the process of metastasis.