Thermal and pH Sensitive Multifunctional Polymer Nanoparticles for Cancer Imaging and Therapy

Fabrication of bovine serum albumin-polyethylene glycol nanoparticle conjugated-folic acid loaded-naringenin as an efficient carrier biomacromolecule for suppression of cancer cells

Flavonoid compounds play an effective role in cancer suppression and today nanocarriers play an important role in improving the physicochemical properties and transmission of these compounds. In this study, polyethylene glycol-modified albumin nanoparticles were synthesized by desolvation method; after loading of naringenin (NRG), folic acid (FA) binding to the surface of nanoparticles was performed (BSA-PEG-FA-NG-NPs). The extent of NRG trapping and FA binding was assessed indirectly using UV absorption methods. The physicochemical properties of BSA-PEG-FA-NG-NPs were investigated by DLS, SEM electron microscopy, and FTIR methods, after which their effects were evaluated on the apoptosis mechanism via MTT, flow cytometry, and qPCR methods. The BSA-PEG-FA-NG-NPs with spherical morphology had dimensions of 205 nm with zeta-potential of 20.61 mV and dispersion index of 0.36. The NRG encapsulation was 84% and the FA binding was 75%. Anticancer effects of BSA-PEG-FA-NG-NPs were confirmed based on inhibiting breast cancer cells (IC50: 922 µg/ml), cell cycle arrest (SubG1 phase), and induction of apoptosis (upregulation of Caspase 3, 8, and 9).

Polymeric Systems for Cancer Immunotherapy: A Review

Immunotherapy holds enormous promise to create a new outlook of cancer therapy by eliminating tumors via activation of the immune system. In immunotherapy, polymeric systems play a significant role in improving antitumor efficacy and safety profile. Polymeric systems possess many favorable properties, including magnificent biocompatibility and biodegradability, structural and component diversity, easy and controllable fabrication, and high loading capacity for immune-related substances. These properties allow polymeric systems to perform multiple functions in immunotherapy, such as immune stimulants, modifying and activating T cells, delivery system for immune cargos, or as an artificial antigen-presenting cell. Among diverse immunotherapies, immune checkpoint inhibitors, chimeric antigen receptor (CAR) T cell, and oncolytic virus recently have been dramatically investigated for their remarkable success in clinical trials. In this report, we review the monotherapy status of immune checkpoint inhibitors, CAR-T cell, and oncolytic virus, and their current combination strategies with diverse polymeric systems.

Hsp70 Promotes SUMO of HIF-1α and Promotes Lung Cancer Invasion and Metastasis

Objective

This study aims to investigate the effect of heat shock protein-70 (Hsp70) on epithelial-mesenchymal transition (EMT) of lung cancer cells under heat stimulation and to explore its possible molecular mechanism.

Methods

qRT-PCR and immunohistochemistry assay were used to detect the expression of Hsp70 in lung cancer tissues and adjacent tissues. EdU assay was used to detect the cell activity. The effect of Hsp70 on the migration and invasion of A549 and NCI-H446 cells was detected by the wound-healing assay and Transwell assay. A tumor transplantation animal model was established to detect the effect of overexpression of Hsp70 on proliferation and metastasis of lung cancer cells. Western blot assay was used to detect the effect of thermal stimulation and overexpression of Hsp70 on SUMO modification of HIF-1α.

Results

The wound-healing rate of A549 and NCI-H446 cells under Hsp70 stimulation was significantly higher than blank control group. At the same time, the number of cells passing through the membrane increased significantly. Hypodermic tumor transplantation in nude mice proved that knockout Hsp70 can inhibit proliferation and metastasis of lung cancer cells. Thermal stimulation upregulated the expression of Hsp70 and promoted SUMO modification of HIF-1α, ultimately promoting the proliferation and metastasis of lung cancer. Inhibition of Hsp70 reverses the effect of thermal stimulation on lung cancer by reducing the SUMO modification of HIF-1α.

Conclusion

Thermal stimulation can promote EMT in A549 and NCI-H446 cells and promote cell migration and invasion in vitro and in vivo by upregulation of Hsp70. This process is associated with the promotion of SUMO modification of HIF-1α.

Near-infrared emissive polymer-coated IR-820 nanoparticles assisted photothermal therapy for cervical cancer cells

Photothermal therapy (PTT) has attracted wide attention due to its noninvasiveness and its thermal ablation ability. As photothermal agents are crucial factor in PTT, those with the characteristics of biocompatibility, non-toxicity and high photothermal stability have attracted great interest. In this work, new indocyanine green (IR-820) was utilized as a photothermal agent and near-infrared (NIR) fluorescence imaging nanoprobe. To improve the biocompatibility, poly(styrene-co-maleic anhydride) (PSMA) was utilized to encapsulate the IR-820 molecules to form novel IR-820@PSMA nanoparticles (NPs). Then, the optical and thermal properties of IR-820@PSMA NPs were studied in detail. The IR-820@PSMA NPs showed excellent photothermal stability and biocompatibility. The cellular uptaking ability of the IR-820@PSMA NPs was further confirmed in HeLa cells by the NIR fluorescent confocal microscopic imaging technique. The IR-820@PSMA NPs assisted PTT of living HeLa cells was conducted under 793 nm laser excitation, and a high PTT efficiency of 73.3% was obtained.

PGMD/curcumin nanoparticles for the treatment of breast cancer

The present study aims at developing PGMD (poly-glycerol-malic acid-dodecanedioic acid)/curcumin nanoparticles based formulation for anticancer activity against breast cancer cells. The nanoparticles were prepared using both the variants of PGMD polymer (PGMD 7:3 and PGMD 6:4) with curcumin (i.e. CUR NP 7:3 and CUR NP 6:4). The size of CUR NP 7:3 and CUR NP 6:4 were found to be ~ 110 and 218 nm with a polydispersity index of 0.174 and 0.36, respectively. Further, the zeta potential of the particles was - 18.9 and - 17.5 mV for CUR NP 7:3 and CUR NP 6:4, respectively. The entrapment efficiency of both the nanoparticles was in the range of 75-81%. In vitro anticancer activity and the scratch assay were conducted on breast cancer cell lines, MCF-7 and MDA-MB-231. The IC50 of the nanoformulations was observed to be 40.2 and 33.6 μM at 48 h for CUR NP 7:3 and CUR NP 6:4, respectively, in MCF-7 cell line; for MDA-MB-231 it was 43.4 and 30.5 μM. Acridine orange/EtBr and DAPI staining assays showed apoptotic features and nuclear anomalies in the treated cells. This was further confirmed by western blot analysis that showed overexpression of caspase 9 indicating curcumin role in apoptosis.

Diosgenin Loaded Polymeric Nanoparticles with Potential Anticancer Efficacy

This study aims to determine the anticancer efficacy of diosgenin encapsulated poly-glycerol malate co-dodecanedioate (PGMD) nanoparticles. Diosgenin loaded PGMD nanoparticles (variants 7:3 and 6:4) were synthesized by the nanoprecipitation method. The synthesis of PGMD nanoparticles was systematically optimized employing the Box-Behnken design and taking into account the influence of various independent variables such as concentrations of each PGMD, diosgenin and PF-68 on the responses such as size and PDI of the particles. Mathematical modeling was done using the Quadratic second order modeling method and response surface analysis was undertaken to elucidate the factor-response relationship. The obtained size of PGMD 7:3 and PGMD 6:4 nanoparticles were 133.6 nm and 121.4 nm, respectively, as measured through dynamic light scattering (DLS). The entrapment efficiency was in the range of 77-83%. The in vitro drug release studies showed diffusion and dissolution controlled drug release pattern following Korsmeyer-Peppas kinetic model. Furthermore, in vitro morphological and cytotoxic studies were performed to evaluate the toxicity of synthesized drug loaded nanoparticles in model cell lines. The IC50 after 48 h was observed to be 27.14 µM, 15.15 µM and 13.91 µM for free diosgenin, PGMD 7:3 and PGMD 6:4 nanoparticles, respectively, when administered in A549 lung carcinoma cell lines.

Emerging Structural and Interfacial Features of Particulate Polymers at the Nanoscale

Particulate polymers at the nanoscale are exceedingly promising for diversified functional applications ranging from biomedical and energy to sensing, labeling, and catalysis. Tailored structural features (i.e., size, shape, morphology, internal softness, interior cross-linking, etc.) determine polymer nanoparticles' impact on the cargo loading capacity and controlled/sustained release, possibility of endocytosis, degradability, and photostability. The designed interfacial features, however (i.e., stimuli-responsive surfaces, wrinkling, surface porosity, shell-layer swellability, layer-by-layer surface functionalization, surface charge, etc.), regulate nanoparticles' interfacial interactions, controlled assembly, movement and collision, and compatibility with the surroundings (e.g., solvent and biological environments). These features define nanoparticles' overall properties/functions on the basis of homogeneity, stability, interfacial tension, and minimization of the surface energy barrier. Lowering of the resultant outcomes is directly influenced by inhomogeneity in the structural and interfacial design through the structure-function relationship. Therefore, a key requirement is to produce well-defined polymer nanoparticles with controlled characteristics. Polymers are amorphous, flexible, and soft, and hence controlling their structural/interfacial features through the single-step process is a challenge. The microfluidics reaction strategy is very promising because of its wide range of advantages such as efficient reactant mixing and fast phase transfer. Overall, this feature article highlights the state-of-the-art synthetic features of polymer nanoparticles with perspectives on their advanced applications.

Synthesis and properties of a stimulus-responsive block polymer

In this study, the synthesis of small molecules and use of an improved “one-pot” method to synthesize the reversible addition–fragmentation chain transfer polymerization (RAFT) reagents have been reported. By comparing with the RAFT reagents synthesized by the traditional “step-by-step” method, it was observed that the reagents synthesized by the two methods had the same structure, however, the improved “one-pot” preparation method results in a significantly higher yield. Subsequently, two different macromolecular CTA segments (PVP-CTA-PVP and PDMAEMA-CTA-PDMAEMA) were prepared by RAFT polymerization, followed by the synthesis of the block polymer PDMAEMA-b-PVP-CTA-PVP-b-PDMAEMA. Through FITR, NMR, GPC and DLS analysis of the block polymer, it was observed that the isotacticity gradually became dominant as the degree of polymerization increased. Further, using NMR spectroscopy to study the effect of pH on the block polymer, the ionization degree of the synthesized polymer in the tumor tissue environment was observed to range between 86.32% to 99.50%, which proved that the synthesized polymers exhibit significant prospects in the medical application.

In this study, two different macromolecular CTA segments (PVP-CTA-PVP and PDMAEMA-CTA-PDMAEMA) were prepared by RAFT polymerization, followed by the synthesis of the block polymer PDMAEMA-b-PVP-CTA-PVP-b-PDMAEMA.

Tumor-Microenvironment-Activatable Nanoreactor Based on a Polyprodrug for Multimodal-Imaging-Medicated Enhanced Cancer Chemo/Phototherapy

Anticancer nanomedicine-based multimodal imaging and synergistic therapy hold great promise in cancer diagnosis and therapy owing to their abilities to improve therapeutic efficiency and reduce unnecessary side effects, producing promising clinical prospects. Herein, we integrated chemotherapeutic drug camptothecin (CPT) and near-infrared-absorbing new indocyanine green (IR820) into a single system by charge interaction and obtained a tumor-microenvironment-activatable PCPT_SS/IR820 nanoreactor to perform thermal/fluorescence/photoacoustic-imaging-guided chemotherapy and photothermal therapy simultaneously. Specifically, the generated PCPT_SS/IR820 showed an excellent therapeutic agent loading content and size stability, and the trials in vitro and in vivo suggested that the smart PCPT_SS/IR820 could deeply permeate into tumor tissues due to its suitable micellar size. Upon near-infrared laser irradiation, the nanoreactor further produced a terrific synergism of chemo-photo treatment for cancer therapy. Therefore, the PCPT_SS/IR820 polyprodrug-based nanoreactor holds outstanding promise for multimodal imaging and combined dual therapy.

Biodegradable nanoparticles as theranostics of ovarian cancer: an overview

Objectives

Above 10 million people are suffering from cancers every year. As per American Cancer Society, more than 22 440 new cases and 14 080 deaths were reported from ovarian cancer yearly worldwide. This review explores the current status, challenges and future perspectives of tumour-targeted theranostic nanoparticles (NPs).

Key findings

Most of the ovarian malignancy cases are uncovered after the disease is in a difficult state due to poor screening techniques and non-specific symptoms. In this manner, forceful and fruitful treatment is required that will indicate insignificant lethal impacts to solid tissue. In the current research, stealth biodegradable NPs are produced as vehicles for imaging and treatment of ovarian cancer as the controlled and targeted delivery of chemotherapeutic as well as imaging agents. To enhance the dependability of the colloidal suspension as well as to increase their circulation lifetime, NPs are introduced by incorporating the functional poly(ethylene glycol) on their surface, which also provides a site to conjugation of focusing on agents to ovarian tissue.

Summary

Biodegradable theranostic NPs can be fabricated and surface engineered without any alteration in drug-loading capacity, safety and efficacy. These NPs have shown promising results in imaging as well as treatment of ovarian cancer.

Targeted photo-chemo therapy of malignancy on the chest wall while cardiopulmonary avoidance based on Fe3O4@ZnO nanocomposites

Treatment of malignancies on the chest wall, like chest wall recurrence of tumor, advanced cutaneous neoplasm and lymphoma, is still a challenge due to the involvement of the critical structures of heart and lung by the conventional strategy. The aim of the current study was to investigate targeted photo-chemo therapy mediated by Fe₃O₄@ZnO nanocomposites for malignancy on the chest wall while cardiopulmonary avoidance. Fe₃O₄@ZnO/Dox nanocomposites, the synthesis of the core-shell Fe₃O₄@ZnO nanocomposites followed by loading doxorubicin (Dox), were prepared to act as multifunctional drug delivery system (DDS). The synergistic anticancer effects on tumor on the chest wall and protection performance of heart and lung were evaluated in vitro and in vivo using cell viability assay, apoptosis detection, histopathologic examination, and serum biochemistry tests. Our observations demonstrated that Fe₃O₄@ZnO/Dox nanocomposites, could play the role of magnetic drug targeting to deliver Dox into tumor tissues and cells to enhance its chemotherapeutic efficiency. Besides, with ultraviolet (UV) illumination, Fe₃O₄@ZnO showed the excellent property of photosensitizer, further attacking the cancer cells by photodynamic therapy (PDT). Thus, apoptosis was synergistically induced by the photo-chemo therapy, resulting in a distinct improvement in anticancer activity. Since UV has a limited penetration distance in tissue, causing PDT to fail in the critical structures of heart and lung, cardiopulmonary hurt could be avoided during the treatment. Therefore, targeted photo-chemo therapy mediated by Fe₃O₄@ZnO nanocomposites may have promise as a potent treatment option for superficial malignancies on the chest wall while cardiopulmonary avoidance.

Polyethylene glycol modified ORMOSIL theranostic nanoparticles for triggered doxorubicin release and deep drug delivery into ovarian cancer spheroids

A novel pegylated multifunctional probe of Ormosil nanoparticles (PEGCDSIR820) loaded with Near Infrared dye (NIR; IR820) and a chemotherapeutic drug, Doxorubicin (DOX) was developed for cancer theranostic applications. PEGCDSIR820 nanoparticles had an average diameter of 58.2±3.1nm, zeta potential of -6.9±0.1mV in cell culture media and stability against aggregation in physiological buffers. The encapsulation efficiency of DOX was 65.0±3.0%, and that of IR820 was 76.0±2.1%. PEGCDSIR820 showed no cytotoxicity in ovarian cancer cells (Skov-3). The cytotoxicity markedly increased when Skov-3 cells incubated with PEGCDSIR820 particles were exposed to 808nm laser due to the combination of adjuvant hyperthermia (43°C) and enhanced DOX release. Exposure to laser enhanced the release of DOX, 45% of DOX release was observed in 3h compared to 23% without laser exposure. Confocal imaging in Skov-3 cells showed that the combination of hyperthermia due to NIR exposure and release of DOX caused cell necrosis. Furthermore, in spheroids exposed to NIR laser penetration of DOX was deeper compared to the absence of laser exposure. Skov-3 spheroids incubated with pegylated nanoparticles for 24h and exposed to laser showed 94% reduction in cell viability. Encapsulation of IR820 in PEGCDSIR820 increased the in-vivo elimination half-life to 41.0±7.2h from 30.5±0.5h of free IR820.

Cyanine based Nanoprobes for Cancer Theranostics

Cyanine dyes are greatly accredited in the development of non-invasive therapy that can "see" and "treat" tumor cells via imaging, photothermal and photodynamic treatment. However, these dyes suffer from poor pharmacokinetics inducing severe toxicity to normal cells, insufficient accumulation in tumor regions and rapid photobleaching when delivered in free forms. Nanoparticles engineered to encapsulate these compounds and delivering them into tumor regions have increased rapidly, however, so far, these nanoparticles (NPs) have not proved to be so effective to circumvent existing challenges. Newly designed multifunctional smart nanocarriers that can improve phototherapeutic properties of these dyes, co-encapsulate multiple potent therapeutic compounds, and simultaneously overcome limitations related to tumor recurrence, metastases, limited intracellular uptake, and tumor hypoxia have potential to revolutionize modern paradigm of cancer therapy. Such cyanine based multifunctional nanocarriers integrating imaging and therapy in a single platform can effectively produce better clinical outcomes in cancer treatment. This review briefly summarizes recent advancements of cyanine nanoprobes that are currently used as imaging/phototherapeutic agents in unimodal/bimodal/trimodal cancer theranostics. Finally, we conclude this review by addressing challenges of pre-existing therapeutic systems and designs adopted to overcome them with a brief insight assimilating future perspective of emerging cyanine-based NPs in cancer theranostics.

Inhibition of H1N1 influenza virus by selenium nanoparticles loaded with zanamivir through p38 and JNK signaling pathways

Zanamivir is an effective drug for influenza virus infection, but strong molecular polarity and aqueous solubility limit its clinical application.

Multifunctional organically modified silica nanoparticles for chemotherapy, adjuvant hyperthermia and near infrared imaging

We report a novel system of organically modified silica nanoparticles (Ormosil) capable of near infrared fluorescence and chemotherapy with adjuvant hyperthermia for image guided cancer therapy. Ormosil nanoparticles were loaded with a chemotherapeutic, Doxorubicin (DOX) and cyanine dye, IR820. Ormosil particles had a mean diameter of 51.2±2.4 nanometers and surface charge of -40.5±0.8mV. DOX was loaded onto Ormosil particles via physical adsorption (FDSIR820) or covalent linkage (CDSIR820) to the silanol groups on the Ormosil surface. Both formulations retained DOX and IR820 over a period of 2 days in aqueous buffer, though CDSIR820 retained more DOX (93.2%) compared to FDSIR820 (77.0%) nanoparticles. Exposure to near infrared laser triggered DOX release from CDSIR820. Uptake of nanoparticles was determined by deconvolution microscopy in ovarian carcinoma cells (Skov-3). CDSIR820 localized in the cell lysosomes whereas cells incubated with FDSIR820 showed DOX fluorescence from the nucleus indicating leakage of DOX from the nanoparticle matrix. FDSIR820 nanoparticles showed severe toxicity in Skov-3 cells whereas CDSIR820 particles had the same cytotoxicity profile as bare (No DOX and IR820) Ormosil particles. Furthermore, exposure of CDSIR820 nanoparticles to Near Infrared laser at 808 nanometers resulted in generation of heat (to 43°C from 37°C) and resulted in enhanced cell killing compared to Free DOX treatment. Bio-distribution studies showed that CDSIR820 nanoparticles were primarily present in the organs of Reticuloendothelial (RES) system.

Human serum albumin (HSA) coated liposomal indocyanine green for in vivo tumor imaging

In this study, a near-infrared (NIR) fluorescent nanoprobe based on indocyanine green (ICG) was synthesized.

Theranostics for hepatocellular carcinoma with Fe3O4@ZnO nanocomposites

An Fe₃O₄@ZnO/Dox/TfR Ab was designed and synthesized as a theranostic agent for hepatocellular carcinoma, allowing for a targeted drug delivery with concurrent chemoradiotherapy and visual MRI evaluation of the therapeutic effect.

Covalent IR820-PEG-diamine nanoconjugates for theranostic applications in cancer

Near-infrared dyes can be used as theranostic agents in cancer management, based on their optical imaging and localized hyperthermia capabilities. However, their clinical translatability is limited by issues such as photobleaching, short circulation times, and nonspecific biodistribution. Nanoconjugate formulations of cyanine dyes, such as IR820, may be able to overcome some of these limitations. We covalently conjugated IR820 with 6 kDa polyethylene glycol (PEG)-diamine to create a nanoconjugate (IRPDcov) with potential for in vivo applications. The conjugation process resulted in nearly spherical, uniformly distributed nanoparticles of approximately 150 nm diameter and zeta potential −0.4±0.3 mV. The IRPDcov formulation retained the ability to fluoresce and to cause hyperthermia-mediated cell-growth inhibition, with enhanced internalization and significantly enhanced cytotoxic hyperthermia effects in cancer cells compared with free dye. Additionally, IRPDcov demonstrated a significantly longer (P<0.05) plasma half-life, elimination half-life, and area under the curve (AUC) value compared with IR820, indicating larger overall exposure to the theranostic agent in mice. The IRPDcov conjugate had different organ localization than did free IR820, with potential reduced accumulation in the kidneys and significantly lower (P<0.05) accumulation in the lungs. Some potential advantages of IR820-PEG-diamine nanoconjugates may include passive targeting of tumor tissue through the enhanced permeability and retention effect, prolonged circulation times resulting in increased windows for combined diagnosis and therapy, and further opportunities for functionalization, targeting, and customization. The conjugation of PEG-diamine with a near-infrared dye provides a multifunctional delivery vector whose localization can be monitored with noninvasive techniques and that may also serve for guided hyperthermia cancer treatments.