Synthesis, characterization, and biological verification of anti-HER2 indocyanine green-doxorubicin-loaded polyethyleneimine-coated perfluorocarbon double nanoemulsions for targeted photochemotherapy of breast cancer cells

Injectable Alginate Complex Hydrogel Loaded with Dual-Drug Nanovectors Offers Effective Photochemotherapy against Triple-Negative Breast Cancer

Triple-negative breast cancer (TNBC), accounting for approximately 20% of breast cancer cases, is a particular subtype that lacks tumor-specific targets and is difficult to treat due to its high aggressiveness and poor prognosis. Chemotherapy remains the major systemic treatment for TNBC. However, its applicability and efficacy in the clinic are usually concerning due to a lack of targeting, adverse side effects, and occurrence of multidrug resistance, suggesting that the development of effective therapeutics is still highly demanded nowadays. In this study, an injectable alginate complex hydrogel loaded with indocyanine green (ICG)-entrapped perfluorocarbon nanoemulsions (IPNEs) and camptothecin (CPT)-doped chitosan nanoparticles (CCNPs), named IPECCNAHG, was developed for photochemotherapy against TNBC. IPNEs with perfluorocarbon can induce hyperthermia and generate more singlet oxygen than an equal dose of free ICG upon near-infrared (NIR) irradiation to achieve photothermal and photodynamic therapy. CCNPs with positive charge may facilitate cellular internalization and provide sustained release of CPT to carry out chemotherapy. Both nanovectors can stabilize agents in the same hydrogel system without interactions. IPECCNAHG integrating IPNEs and CCNPs enables stage-wise combinational therapeutics that may overcome the issues described above. With 60 s of NIR irradiation, IPECCNAHG significantly inhibited the growth of MDA-MB-231 tumors in the mice without systemic toxicity within the 21 day treatment. We speculate that such anticancer efficacy was accomplished by phototherapy followed by chemotherapy, where cancer cells were first destroyed by IPNE-derived hyperthermia and singlet oxygen, followed by sustained damage with CPT after internalization of CCNPs; a two-stage tumoricidal process. Taken together, the developed IPECCNAHG is anticipated to be a feasible tool for TNBC treatment in the clinic.

Multi-charged nanoemulsion for photodynamic treatment of glioblastoma cell line in 2D and 3D in vitro models

Multi-charged nanoemulsions (NE) were designed to deliver Cannabidiol (CBD), Indocyanine green (ICG), and Protoporphyrin (PpIX) to treat glioblastoma (GBM) through Photodynamic Therapy (PDT). The phase-inversion temperature (PIT) method resulted in a highly stable NE that can be scaled easily, with a six-month shelf-life. We observed the quasi-spherical morphology of the nanoemulsions without any unencapsulated material and that 89% (± 5.5%) of the material was encapsulated. All physicochemical properties were within the expected range for a nanostructured drug delivery system, making these multi-charged nanoemulsions promising for further research and development. NE-PIC (NE-Protoporphyrin + Indocyanine + CBD) was easily internalized on GBM cells after three hours of incubation. Nanoemulsion (NE and NE-PIC) did not result in significant cytotoxicity, even for GBM or non-tumorigenic cell lines (NHF). Phototoxicity was significantly higher for the U87MG cell than the T98G cell when exposed to: visible (430 nm) and infrared (810 nm) laser light, with a difference of about 20%. From 50 mJ.cm-2, the viability of GBM cell lines decreases significantly, ranging from 65% to 85%. The NE-PIC was also effective for inhibiting cell proliferation into a 3D spheroidal GBM cell model, which is promising for mimicking the tumor cell environment. Irradiation at 810 nm was more effective in treating spheroid due to its deeper penetration in complex structures. NE-PIC has the potential as a drug delivery system for photoinactivation and photo diagnostic of GBM cell lines, taking advantage of the versatility of its active components.

Biomimetic Theranostic Agents with Superior NIR-II Photoacoustic and Magnetic Resonance Imaging Performance for Targeted Photothermal Therapy of Prostate Cancer

The accurate diagnosis and treatment of prostate cancer at an early stage is crucial to reduce mortality rates. However, the limited availability of theranostic agents with active tumor-targeting abilities hinders imaging sensitivity and therapeutic efficiency. To address this challenge, we have developed biomimetic cell membrane-modified Fe₂O₃ nanoclusters implanted in polypyrrole (CM-LFPP), achieving photoacoustic/magnetic resonance dual-modal imaging-guided photothermal therapy of prostate cancer. The CM-LFPP exhibits strong absorption in the second near-infrared window (NIR-II, 1000-1700 nm), showing high photothermal conversion efficiency of up to 78.7% under 1064 nm laser irradiation, excellent photoacoustic imaging capabilities, and good magnetic resonance imaging ability with a T2 relaxivity of up to 48.7 s^-1 mM^-1. Furthermore, the lipid encapsulation and biomimetic cell membrane modification enable CM-LFPP to actively target tumors, leading to a high signal-to-background ratio of ~30.2 for NIR-II photoacoustic imaging. Moreover, the biocompatible CM-LFPP enables low-dose (0.6 W cm^-2) photothermal therapy of tumors under 1064 nm laser irradiation. This technology offers a promising theranostic agent with remarkable photothermal conversion efficiency in the NIR-II window, providing highly sensitive photoacoustic/magnetic resonance imaging-guided prostate cancer therapy.

Recent advances of Pluronic-based copolymers functionalization in biomedical applications

The design of polymeric biocompatible nanomaterials for biological and medical applications has received special attention in recent years. Among different polymers, the triblock type copolymers (EO)_x(PO)_y(EO)_x or Pluronics® stand out due its favorable characteristics such as biocompatibility, low tissue adhesion, thermosensitivity, and structural capacity to produce different types of macro and nanostructures, e.g. micelles, vesicles, nanocapsules, nanospheres, and hydrogels. However, Pluronic itself is not the "magic bullet" and its functionalization via chemical synthesis following biologically oriented design rules is usually required aiming to improve its properties. Therefore, this paper presents some of the main publications on new methodologies for synthetic modifications and applications of Pluronic-based nanoconstructs in the biomedical field in the last 15 years. In general, the polymer modifications aim to improve physical-chemical properties related to the micellization process or physical entrapment of drug cargo, responsive stimuli, active targeting, thermosensitivity, gelling ability, and hydrogel formation. Among these applications, it can be highlighted the treatment of malignant neoplasms, infectious diseases, wound healing, cellular regeneration, and tissue engineering. Functionalized Pluronic has also been used for various purposes, including medical diagnosis, medical imaging, and even miniaturization, such as the creation of lab-on-a-chip devices. In this context, this review discusses the main scientific contributions to the designing, optimization, and improvement of covalently functionalized Pluronics aiming at new strategies focused on the multiple areas of the biomedical field.

Current Challenges and Opportunities of Photodynamic Therapy against Cancer

BACKGROUND

Photodynamic therapy (PDT) is an established, minimally invasive treatment for specific types of cancer. During PDT, reactive oxygen species (ROS) are generated that ultimately induce cell death and disruption of the tumor area. Moreover, PDT can result in damage to the tumor vasculature and induce the release and/or exposure of damage-associated molecular patterns (DAMPs) that may initiate an antitumor immune response. However, there are currently several challenges of PDT that limit its widespread application for certain indications in the clinic.

METHODS

A literature study was conducted to comprehensively discuss these challenges and to identify opportunities for improvement.

RESULTS

The most notable challenges of PDT and opportunities to improve them have been identified and discussed.

CONCLUSIONS

The recent efforts to improve the current challenges of PDT are promising, most notably those that focus on enhancing immune responses initiated by the treatment. The application of these improvements has the potential to enhance the antitumor efficacy of PDT, thereby broadening its potential application in the clinic.

Pluronic® triblock copolymer-based nanoformulations for cancer therapy: A 10-year overview

This paper provides a review of the literature on the use of Pluronic® triblock copolymers for drug encapsulation over the last 10 years. A special focus is given to the progress of drug delivery systems (e.g., micelles, liposomes, micro/nanoemulsions, hydrogels and nanogels, and polymersomes and niosomes); the beneficial aspects of Pluronic® triblock copolymers as biological response modifiers and as pharmaceutical additives, adjuvants, and stabilizers, are also discussed. The advantages and limitations encountered in developing site-specific targeting approaches based on Pluronic-based nanostructures in cancer treatment are highlighted, in addition to innovative examples for improving tumor cytotoxicity while reducing side effects.

A multifunctional targeted nanoprobe with high NIR-II PAI/MRI performance for precise theranostics of orthotopic early-stage hepatocellular carcinoma

Early diagnosis and effective treatment of hepatocellular carcinoma (HCC) is quite critical for improving patients' prognosis. The combination of second near-infrared window photoacoustic imaging (NIR-II PAI) and T₂-magnetic resonance imaging (T₂-MRI) is promising for achieving omnibearing information on HCC diagnosis due to the complementary advantages of outstanding optical contrast, high temporospatial resolution and soft-tissue resolution. Thus, the rational design of a multifunctional targeted nanoplatform with outstanding performance in dual-modal NIR-II PAI/T₂-MRI is particularly valuable for precise diagnosis and imaging-guided non-invasive photothermal therapy (PTT) of early-stage HCC. Herein, a versatile targeted organic-inorganic hybrid nanoprobe was synthesized as a HCC-specific contrast agent for sensitive and efficient theranostics. The developed multifunctional targeted nanoprobe yielded superior HCC specificity, reliable stability and biocompatibility, high imaging contrast in both NIR-II PAI and T₂-MRI, and an excellent photothermal conversion efficiency (74.6%). Furthermore, the theranostic efficiency of the targeted nanoprobe was systematically investigated using the orthotopic early HCC-bearing mice model. The NIR-II PAI exhibited sensitive detection of ultra-small HCCs (diameter less than 1.8 mm) and long-term real-time monitoring of the tumor and nanoprobe targeting process in deep tissues. The T₂-MRI demonstrated clear imaging contrast and a spatial relationship between micro-HCC and adjacent structures for a comprehensive description of the tumor. Moreover, when using the targeted nanoprobe, the non-invasively targeted PTT of orthotopic early HCC was carried out under reliable dual-modal imaging guidance with remarkable anti-tumor efficiency and biosafety. This study provides an insight for constructing a multifunctional targeted nanoplatform for precise and comprehensive theranostics of early-stage HCC, which would greatly benefit the patients in the era of precision medicine.

Phototherapy and multimodal imaging of cancers based on perfluorocarbon nanomaterials

Phototherapy, such as photodynamic therapy (PDT) and photothermal therapy (PTT), possesses unique characteristics of non-invasiveness and minimal side effects in cancer treatment, compared with conventional therapies. However, the ubiquitous tumor hypoxia microenvironments could severely reduce the efficacy of oxygen-consuming phototherapies. Perfluorocarbon (PFC) nanomaterials have shown great practical value in carrying and transporting oxygen, which makes them promising agents to overcome tumor hypoxia and extend reactive oxygen species (ROS) lifetime to improve the efficacy of phototherapy. In this review, we summarize the latest advances in PFC-based PDT and PTT, and combined multimodal imaging technologies in various cancer types, aiming to facilitate their application-oriented clinical translation in the future.

Therapeutic oxygen delivery by perfluorocarbon-based colloids

After the protocol-related indecisive clinical trial of Oxygent, a perfluorooctylbromide/phospholipid nanoemulsion, in cardiac surgery, that often unduly assigned the observed untoward effects to the product, the development of perfluorocarbon (PFC)-based O₂ nanoemulsions ("blood substitutes") has come to a low. Yet, significant further demonstrations of PFC O₂-delivery efficacy have continuously been reported, such as relief of hypoxia after myocardial infarction or stroke; protection of vital organs during surgery; potentiation of O₂-dependent cancer therapies, including radio-, photodynamic-, chemo- and immunotherapies; regeneration of damaged nerve, bone or cartilage; preservation of organ grafts destined for transplantation; and control of gas supply in tissue engineering and biotechnological productions. PFC colloids capable of augmenting O₂ delivery include primarily injectable PFC nanoemulsions, microbubbles and phase-shift nanoemulsions. Careful selection of PFC and other colloid components is critical. The basics of O₂ delivery by PFC nanoemulsions will be briefly reminded. Improved knowledge of O₂ delivery mechanisms has been acquired. Advanced, size-adjustable O₂-delivering nanoemulsions have been designed that have extended room-temperature shelf-stability. Alternate O₂ delivery options are being investigated that rely on injectable PFC-stabilized microbubbles or phase-shift PFC nanoemulsions. The latter combine prolonged circulation in the vasculature, capacity for penetrating tumor tissues, and acute responsiveness to ultrasound and other external stimuli. Progress in microbubble and phase-shift emulsion engineering, control of phase-shift activation (vaporization), understanding and control of bubble/ultrasound/tissue interactions is discussed. Control of the phase-shift event and of microbubble size require utmost attention. Further PFC-based colloidal systems, including polymeric micelles, PFC-loaded organic or inorganic nanoparticles and scaffolds, have been devised that also carry substantial amounts of O₂. Local, on-demand O₂ delivery can be triggered by external stimuli, including focused ultrasound irradiation or tumor microenvironment. PFC colloid functionalization and targeting can help adjust their properties for specific indications, augment their efficacy, improve safety profiles, and expand the range of their indications. Many new medical and biotechnological applications involving fluorinated colloids are being assessed, including in the clinic. Further uses of PFC-based colloidal nanotherapeutics will be briefly mentioned that concern contrast diagnostic imaging, including molecular imaging and immune cell tracking; controlled delivery of therapeutic energy, as for noninvasive surgical ablation and sonothrombolysis; and delivery of drugs and genes, including across the blood-brain barrier. Even when the fluorinated colloids investigated are designed for other purposes than O₂ supply, they will inevitably also carry and deliver a certain amount of O₂, and may thus be considered for O₂ delivery or co-delivery applications. Conversely, O₂-carrying PFC nanoemulsions possess by nature a unique aptitude for ¹⁹F MR imaging, and hence, cell tracking, while PFC-stabilized microbubbles are ideal resonators for ultrasound contrast imaging and can undergo precise manipulation and on-demand destruction by ultrasound waves, thereby opening multiple theranostic opportunities.

Engineered photo-chemical therapeutic nanocomposites provide effective antibiofilm and microbicidal activities against bacterial infections in porous devices

Today, prosthetic joint infection (PJI) is still a relatively rare but devastating complication following total hip and/or knee arthroplasty. The treatment of PJI is difficult due to a number of obstacles, such as microbial drug resistance, biofilm protection, and insufficient immune activity, which dramatically diminish the cure rate of PJI to <50%. To efficiently eradicate the bacteria hiding in the implant, photo-chemical joint antibacterial therapeutics based on indocyanine green (ICG) and rifampicin (RIF) co-loaded PLGA nanoparticles (IRPNPs) were developed in this study. The IRPNPs were first characterized as a spherical nanostructure with a size of 266 ± 18.2 nm and a surface charge of -28 ± 1.6 mV. In comparison with freely dissolved ICG, the IRPNPs may confer enhanced thermal stability to the encapsulated ICG and are able to provide a comparable hyperthermic effect and increased production of singlet oxygen under 808 nm near infrared (NIR) exposure with an intensity of 6 W cm-2. Based on the spectrophotometric analysis, the IRPNPs with ≥20-/3.52 μM ICG/RIF were able to provide remarkable antibiofilm and antimicrobial effects against bacteria in a porous silicon bead upon NIR exposure in vitro. Through the analysis of the microbial population index in an animal study, ≥70% Staphylococcus capitis subsp. urealyticus grown in a porous silicon bead in vivo can be successfully eliminated without organ damage or inflammatory lesions around the implant by using IRPNPs + NIR irradiation every 72 h for 9 days. The resulting bactericidal efficacy was approximately three-fold higher than that resulting from using an equal amount of free RIF alone. Taken together, we anticipate that IRPNP-mediated photochemotherapy can serve as a feasible antibacterial approach for PJI treatment in the clinic.

Current Targets and Bioconjugation Strategies in Photodynamic Diagnosis and Therapy of Cancer

Photodynamic diagnosis (PDD) and therapy (PDT) are emerging, non/minimally invasive techniques for cancer diagnosis and treatment. Both techniques require a photosensitizer and light to visualize or destroy cancer cells. However, a limitation of conventional, non-targeted PDT is poor selectivity, causing side effects. The bioconjugation of a photosensitizer to a tumor-targeting molecule, such as an antibody or a ligand peptide, is a way to improve selectivity. The bioconjugation strategy can generate a tumor-targeting photosensitizer conjugate specific for cancer cells, or ideally, for multiple tumor compartments to improve selectivity and efficacy, such as cancer stem cells and tumor neovasculature within the tumor microenvironment. If successful, such targeted photosensitizer conjugates can also be used for specific visualization and detection of cancer cells and/or tumor angiogenesis (an early event in tumorigenesis) with the hope of an early diagnosis of cancer. The purpose of this review is to summarize some current promising target molecules, e.g., tissue factor (also known as CD142), and the currently used bioconjugation strategies in PDT and PDD, with a focus on newly developed protein photosensitizers. These are genetically engineered photosensitizers, with the possibility of generating a fusion protein photosensitizer by recombinant DNA technology for both PDT and PDD without the need of chemical conjugation. We believe that providing an overview of promising targets and bioconjugation strategies will aid in driving research in this field forward towards more effective, less toxic, and non- or minimally invasive treatment and diagnosis options for cancer patients.

Oxygen therapeutic agents to target hypoxia in cancer treatment

Solid tumors have abnormal microcirculation that limits oxygen delivery and leads to a hypoxic tumor microenvironment. Tumor hypoxia stabilizes the transcription factor HIF-1α that can trigger immunosuppression through A2A adenosine receptors which prevents immune attack on tumors. In addition, success of chemotherapy and radiation therapy appears to be dependent on oxygen levels. Two main pharmaceutical classes of agents (hemoglobin based and perfluorocarbon man-made carbon oils) have been tested in tumor models as enhanced oxygen therapeutics. This article will review how these agents function as well as examine work to date with both drug classes.

Review: Organic nanoparticle based active targeting for photodynamic therapy treatment of breast cancer cells

Targeted Photodynamic therapy (TPDT) is a non-invasive and site-specific treatment modality, which has been utilized to eradicate cancer tumour cells with photoactivated chemicals or photosensitizers (PSs), in the presence of laser light irradiation and molecular tissue oxygen. Breast cancer is the commonest cancer among women worldwide and is currently treated using conventional methods such as chemotherapy, radiotherapy and surgery. Despite the recent advancements made in PDT, poor water solubility and non-specificity of PSs, often affect the overall effectivity of this unconventional cancer treatment. With respect to conventional PS obstacles, great strides have been made towards the application of targeted nanoparticles in PDT to resolve these limitations. Therefore, this review provides an overview of scientific peer reviewed published studies in relation to functionalized organic nanoparticles (NPs) for effective TPDT treatment of breast cancer over the last 10 years (2009 to 2019). The main aim of this review is to highlight the importance of organic NP active based PDT targeted drug delivery systems, to improve the overall biodistribution of PSs in breast cancer tumour's.

Indocyanine Green-Parthenolide Thermosensitive Liposome Combination Treatment for Triple-Negative Breast Cancer

Background

Certain patients with triple-negative breast cancer cannot tolerate the serious adverse effects of cytotoxic chemotherapy agents, which significantly affect the disease prognosis.

Purpose

Research into the combined use of photosensitizers and non-cytotoxic antineoplastic drugs for the safe treatment of triple-negative breast cancer is vital.

Methods

In this study, the photosensitizer indocyanine green and the natural drug parthenolide were co-loaded into thermosensitive liposomes. Under a near-infrared irradiation, indocyanine green reached excitation levels, releasing heat, and the liposome underwent a phase transition, releasing the drug were researched.

Results

Thus, indocyanine green and parthenolide exert synergistic antineoplastic effects. In the nude mice xenograft MDA-MB-231 tumor model, the tumor inhibition rate of indocyanine green-parthenolide thermosensitive liposomes was approximately 2.08-fold than that of paclitaxel and demonstrated a good initial safety evaluation.

Conclusion

Photosensitizers and non-cytotoxic antineoplastic agents in combination with nanoscale carriers should be further investigated for the treatment of tumors.

Bioinspired Polymeric-based Core-shell Smart Nano-systems

Smart nanosystems (SNs) have the potential to revolutionize drug delivery. Conventional drug delivery systems have poor drug-loading, early burst release, limited therapeutic effects, etc. Thus, to overcome these problems, researchers have taken advantage of the host-guest interactions as bioinspired nanosystems which can deliver nanocarriers more efficiently with the maximum drug loading capacity and improved therapeutic efficacy as well as bioavailability. SNs employ nanomaterials to form cage molecules by entrapping new nanocarriers called smart nanosystems in their cargo and design. The activities of SNs are based on responsive materials that interact with the stimuli either by changing their properties or conformational structures. The aptitude of living systems to respond to stimuli and process information has encouraged researchers to build up integrated nanosystems exhibiting similar function and therapeutic response. Various smart materials, including polymers, have been exhaustively employed in fabricating different stimuli-responsive nanosystems which can deliver bioactive molecules to a specific site for a certain period with minimal side effects. SNs have been widely explored to deliver diverse kinds of therapeutic agents ranging from bioactive compounds, genes, and biopharmaceuticals like proteins and peptides, to diagnostic imaging agents for biomedical applications. Nanotechnology-based different nanosystems are promising for health care issues. The advancement of SNs with physical science and engineering technology in synthesizing nanostructures and their physicochemical characterization should be exploited in medicine and healthcare for reducing mortality rate, morbidity, disease prevalence and general societal burden.

Synergy of Chemo- and Photodynamic Therapies with C60 Fullerene-Doxorubicin Nanocomplex

A nanosized drug complex was explored to improve the efficiency of cancer chemotherapy, complementing it with nanodelivery and photodynamic therapy. For this, nanomolar amounts of a non-covalent nanocomplex of Doxorubicin (Dox) with carbon nanoparticle C₆₀ fullerene (C₆₀) were applied in 1:1 and 2:1 molar ratio, exploiting C₆₀ both as a drug-carrier and as a photosensitizer. The fluorescence microscopy analysis of human leukemic CCRF-CEM cells, in vitro cancer model, treated with nanocomplexes showed Dox’s nuclear and C₆₀’s extranuclear localization. It gave an opportunity to realize a double hit strategy against cancer cells based on Dox’s antiproliferative activity and C₆₀’s photoinduced pro-oxidant activity. When cells were treated with 2:1 C₆₀-Dox and irradiated at 405 nm the high cytotoxicity of photo-irradiated C₆₀-Dox enabled a nanomolar concentration of Dox and C₆₀ to efficiently kill cancer cells in vitro. The high pro-oxidant and pro-apoptotic efficiency decreased IC₅₀ 16, 9 and 7 × 10³-fold, if compared with the action of Dox, non-irradiated nanocomplex, and C₆₀’s photodynamic effect, correspondingly. Hereafter, a strong synergy of therapy arising from the combination of C₆₀-mediated Dox delivery and C₆₀ photoexcitation was revealed. Our data indicate that a combination of chemo- and photodynamic therapies with C₆₀-Dox nanoformulation provides a promising synergetic approach for cancer treatment.

Gelatin-chlorin e6 conjugate for in vivo photodynamic therapy

BACKGROUND

Improving the water solubility of hydrophobic photosensitizer and increasing its accumulation in tumor tissue are essential for in vivo photodynamic therapy (PDT). Considering commercialization or clinical application in future, it will be promising to achieve these purposes by developing new agents with simple and non-toxic structure.

RESULTS

We conjugated multiple chlorin e6 (Ce6) molecules to gelatin polymer, synthesizing two types of gelatin-Ce6 conjugates with different amounts of Ce6: gelatin-Ce6-2 and gelatin-Ce6-8. The resulting conjugates remained soluble in aqueous solutions for a longer time than hydrophobic Ce6. The conjugates could generate singlet oxygen and kill tumor cells upon laser irradiation. After intravenous injection into SCC-7 tumor-bearing mice, gelatin-Ce6-2 showed prolonged blood circulation and highly increased accumulation in tumor tissue as observed in real-time imaging in vivo. After laser irradiation, gelatin-Ce6-2 suppressed tumor growth completely and enabled improved PDT compared to free Ce6 and gelatin-Ce6-8.

CONCLUSIONS

This work demonstrates that a simple structure based on photosensitizer and gelatin can highly improve water solubility and stability. Superior tumor tissue accumulation and increased therapeutic efficacy of gelatin-Ce6 during in vivo PDT showed its high potential for clinical application.

Specific drug delivery efficiently induced human breast tumor regression using a lipoplex by non-covalent association with anti-tumor antibodies

Background

A cationic liposome-PEG-PEI complex (LPPC) was employed as a carrier for achieving targeted delivery of drug to human epidermal growth factor receptor-2 (HER2/neu)-expressing breast cancer cells. LPPC can be easily loaded with an anti-tumor drug and non-covalently associated with an anti-tumor antibody such as Herceptin that is clinically used to rapidly form immunoparticles within 1 h.

Results

Drug-loaded LPPC have an average size about 250 nm and a zeta potential of about 40 mV. Herceptin was complexed onto surface of the LPPC to form the drug/LPPC/Herceptin complexes. The size of curcumin/LPPC/Herceptin complexes were 280 nm and the zeta potentials were about 23 mV. Targeting ability of this delivery system was demonstrated through specific binding on surface of cells and IVIS images in vivo, which showed specific binding in HER2-positive SKBR3 cells as compared to HER2-negative Hs578T cells. Only the drug/LPPC/Herceptin complexes displayed dramatically increased the cytotoxic activity in cancer cells. Both in vitro and in vivo results indicated that Herceptin adsorbed on LPPC directed the immunocomplex towards HER2/neu-positive cells but not HER2/neu-negative cells. The complexes with either component (curcumin or doxorubicin) used in the LPPC-delivery system provided a better therapeutic efficacy compared to the drug treatment alone and other treatment groups, including clinical dosages of Herceptin and LipoDox, in a xenografted model.

Conclusions

LPPC displays important clinical implications by easily introducing a specific targeting characteristic to drugs utilized for breast cancer therapy.

Electronic supplementary material

The online version of this article (10.1186/s12951-019-0457-3) contains supplementary material, which is available to authorized users.

Polymer-Based Nanocarriers for Co-Delivery and Combination of Diverse Therapies against Cancers

Cancer gives rise to an enormous number of deaths worldwide nowadays. Therefore, it is in urgent need to develop new therapies, among which combined therapies including photothermal therapy (PTT) and chemotherapy (CHT) using polymer-based nanocarriers have attracted enormous interest due to the significantly enhanced efficacy and great progress has been made so far. The preparation of such nanocarriers is a comprehensive task involving the cooperation of nanomaterial science and biomedicine science. In this review, we try to introduce and analyze the structure, preparation and synergistic therapeutic effect of various polymer-based nanocarriers composed of anti-tumor drugs, nano-sized photothermal materials and other possible parts. Our effort may bring benefit to future exploration and potential applications of similar nanocarriers.