Design strategy and research progress of multifunctional nanoparticles in lung cancer therapy

INTRODUCTION

Lung cancer is one of the cancer types with the highest mortality rate, exploring a more effective treatment modality that improves therapeutic efficacy while mitigating side effects is now an urgent requirement. Designing multifunctional nanoparticles can be used to overcome the limitations of drugs and conventional drug delivery systems. Nanotechnology has been widely researched, and through different needs, suitable nanocarriers can be selected to load anti-cancer drugs to improve the therapeutic effect. It is foreseeable that with the rapid development of nanotechnology, more and more lung cancer patients will benefit from nanotechnology. This paper reviews the merits of various multifunctional nanoparticles in the treatment of lung cancer to provide novel ideas for lung cancer treatment.

AREAS COVERED

This review focuses on summarizing various nanoparticles for targeted lung cancer therapy and their advantages and disadvantages, using nanoparticles loaded with anti-cancer drugs, delivered to lung cancer sites, enhancing drug half-life, improving anti-cancer drug efficacy and reducing side effects.

EXPERT OPINION

The delivery mode of nanoparticles with superior pharmacokinetic properties in the in vivo circulation enhances the half-life of the drug, and provides tissue-targeted selectivity and the ability to overcome biological barriers, bringing a revolution in the field of oncology.

Hydroxyapatite Nanoparticles for Improved Cancer Theranostics

Beyond their well-known applications in bone tissue engineering, hydroxyapatite nanoparticles (HAp NPs) have also been showing great promise for improved cancer therapy. The chemical structure of HAp NPs offers excellent possibilities for loading and delivering a broad range of anticancer drugs in a sustained, prolonged, and targeted manner and thus eliciting lower complications than conventional chemotherapeutic strategies. The incorporation of specific therapeutic elements into the basic composition of HAp NPs is another approach, alone or synergistically with drug release, to provide advanced anticancer effects such as the capability to inhibit the growth and metastasis of cancer cells through activating specific cell signaling pathways. HAp NPs can be easily converted to smart anticancer agents by applying different surface modification treatments to facilitate the targeting and killing of cancer cells without significant adverse effects on normal healthy cells. The applications in cancer diagnosis for magnetic and nuclear in vivo imaging are also promising as the detection of solid tumor cells is now achievable by utilizing superparamagnetic HAp NPs. The ongoing research emphasizes the use of HAp NPs in fabricating three-dimensional scaffolds for the treatment of cancerous tissues or organs, promoting the regeneration of healthy tissue after cancer detection and removal. This review provides a summary of HAp NP applications in cancer theranostics, highlighting the current limitations and the challenges ahead for this field to open new avenues for research.

Spatial Distribution Control of Antimicrobial Peptides through a Novel Polymeric Carrier for Safe and Efficient Cancer Treatment

Antimicrobial peptides (AMPs) hold great potential for use in tumor treatment. However, developing AMP-based antitumor therapies is challenging due to circulatory instability, hemolytic toxicity, low selectivity, and poor cell permeability of AMPs. In this study, a polymeric carrier for AMPs (denoted as PAMP_m -co-PPBE_n /PCA) is presented that effectively enhances their anticancer efficacy while minimizing their potential side effects. By integrating multiple responsive structures at the molecular level, the carrier finely controls the spatial distribution of AMPs in different biological microenvironments, thereby effectively modulating their membranolytic ability. Upon employing KLA as the model AMP, the polymeric carrier's hemolytic toxicity during blood circulation is suppressed, its cellular internalization when reaching tumor tissues facilitated, and its membranolytic toxicity toward the mitochondria upon entering cancer cells restored and further enhanced. Animal studies indicate that this approach significantly improves the antitumor efficacy of KLA and reduces its toxicity. Considering that the loading method for most AMPs is identical to that of KLA, the polymeric carrier reported in this study may provide a feasible approach for the development of AMP-based cancer treatments.

Advances of nanomedicines in breast cancer metastasis treatment targeting different metastatic stages

Breast cancer is the most common tumor in women, and the metastasis further increases the malignancy with extremely high mortality. However, there is almost no effective method in the clinic to completely inhibit breast cancer metastasis due to the dynamic multistep process with complex pathways and scattered occurring site. Nowadays, nanomedicines have been evidenced with great potential in treating cancer metastasis. In this review, we summarize the latest research advances of nanomedicines in anti-metastasis treatment. Strategies are categorized according to the metastasis dynamics, including primary tumor, circulating tumor cells, pre-metastatic niches and secondary tumor. In each different stage of metastasis process, nanomedicines are designed specifically with different functions. At the end of the review, we give our perspectives on current limitations and future directions in anti-metastasis therapy. We expect the review provides comprehensive understandings of anti-metastasis therapy for breast cancer, and boosts the clinical translation in the future to improve women's health.

Sustained and controlled delivery of doxorubicin from an in-situ setting biphasic hydroxyapatite carrier for local treatment of a highly proliferative human osteosarcoma

Doxorubicin (DOX) is a cornerstone drug in the treatment of osteosarcoma. However, achieving sufficient concentration in the tumor tissue after systemic administration with few side effects has been a challenge. Even with the most advanced nanotechnology approaches, less than 5% of the total administered drug gets delivered to the target site. Alternatives to increase the local concentration of DOX within the tumor using improved drug delivery methods are needed. In this study, we evaluate a clinically approved calcium sulfate/hydroxyapatite (CaS/HA) carrier, both in-vitro and in-vivo, for local, sustained and controlled delivery of DOX to improve osteosarcoma treatment. In-vitro drug release studies indicated that nearly 28% and 36% of the loaded drug was released over a period of 4-weeks at physiological pH (7.4) and acidic pH (5), respectively. About 63% of the drug had been released after 4-weeks in-vivo. The efficacy of the released drug from the CaS/HA material was verified on two human osteosarcoma cell lines MG-63 and 143B. It was demonstrated that the released drug fractions functioned the same way as the free drug without impacting its efficacy. Finally, the carrier system with DOX was assessed using two clinically relevant human osteosarcoma xenograft models. Compared to no treatment or the clinical standard of care with systemic DOX administration, the delivery of DOX using a CaS/HA biomaterial could significantly hinder tumor progression by inhibiting angiogenesis and cell proliferation. Our results indicate that a clinically approved CaS/HA biomaterial containing cytostatics could potentially be used for the local treatment of osteosarcoma. STATEMENT OF SIGNIFICANCE: The triad of doxorubicin (DOX), methotrexate and cisplatin has routinely been used for the treatment of osteosarcoma. These drugs dramatically improved the prognosis, but 45-55% of the patients respond poorly to the treatment with low 5-year survival. In the present study, we repurpose the cornerstone drug DOX by embedding it in a calcium sulfate/hydroxyapatite (CaS/HA) biomaterial, ensuring a spatio-temporal drug release and a hypothetically higher and longer lasting intra-tumoral concentration of DOX. This delivery system could dramatically hinder the progression of a highly aggressive osteosarcoma compared to systemic administration, by inhibiting angiogenesis and cell proliferation. Our data show an efficient method for supplementary osteosarcoma treatment with possible rapid translational potential due to clinically approved constituents.

Emerging nanomedicine-based therapeutics for hematogenous metastatic cascade inhibition: Interfering with the crosstalk between "seed and soil"

Despite considerable progresses in cancer treatment, tumor metastasis is still a thorny issue, which leads to majority of cancer-related deaths. In hematogenous metastasis, the concept of “seed and soil” suggests that the crosstalk between cancer cells (seeds) and premetastatic niche (soil) facilitates tumor metastasis. Considerable efforts have been dedicated to inhibit the tumor metastatic cascade, which is a highly complicated process involving various pathways and biological events. Nonetheless, satisfactory therapeutic outcomes are rarely observed, since it is a great challenge to thwart this multi-phase process. Recent advances in nanotechnology-based drug delivery systems have shown great potential in the field of anti-metastasis, especially compared with conventional treatment methods, which are limited by serious side effects and poor efficacy. In this review, we summarized various factors involved in each phase of the metastatic cascade ranging from the metastasis initiation to colonization. Then we reviewed current approaches of targeting these factors to stifle the metastatic cascade, including modulating primary tumor microenvironment, targeting circulating tumor cells, regulating premetastatic niche and eliminating established metastasis. Additionally, we highlighted the multi-phase targeted drug delivery systems, which hold a better chance to inhibit metastasis. Besides, we demonstrated the limitation and future perspectives of nanomedicine-based anti-metastasis strategies.

An oroxylin A-loaded aggregation-induced emission active polymeric system greatly increased the antitumor efficacy against squamous cell carcinoma

Squamous cell carcinoma (SCC) is a usually responds poorly to treatment suffers from poor therapeutic benefits while oroxylin A (OA) is a promising flavonoid with high anticancer efficacy against various cancer types. Here in our study, in order to reveal the potential of OA based drug delivery systems (DDSs) in the treatment of SCC, we firstly revealed that OA had a certain pharmacodynamic effect on skin SCC (A431 cells). Afterwards, OA was loaded into a newly synthesized aggregation-induced emission (AIE)-active polymer to construct OA-loaded PDots for the first time. Our results revealed that OA-loaded PDots showed preferable drug loading and enhanced stability. Moreover, the DDS was also capable of self-illumination in the aggregate state to reveal the uptake profile. Most importantly, the DDS showed much more elevated anticancer benefits than free OA in vitro and advanced tumor targetability in vivo, suggesting that it might be a promising system against SCC.

Strategies for Targeting Gene Therapy in Cancer Cells With Tumor-Specific Promoters

Cancer is the second cause of death worldwide, surpassed only by cardiovascular diseases, due to the lack of early diagnosis, and high relapse rate after conventional therapies. Chemotherapy inhibits the rapid growth of cancer cells, but it also affects normal cells with fast proliferation rate. Therefore, it is imperative to develop other safe and more effective treatment strategies, such as gene therapy, in order to significantly improve the survival rate and life expectancy of patients with cancer. The aim of gene therapy is to transfect a therapeutic gene into the host cells to express itself and cause a beneficial biological effect. However, the efficacy of the proposed strategies has been insufficient for delivering the full potential of gene therapy in the clinic. The type of delivery vehicle (viral or non viral) chosen depends on the desired specificity of the gene therapy. The first gene therapy trials were performed with therapeutic genes driven by viral promoters such as the CMV promoter, which induces non-specific toxicity in normal cells and tissues, in addition to cancer cells. The use of tumor-specific promoters over-expressed in the tumor, induces specific expression of therapeutic genes in a given tumor, increasing their localized activity. Several cancer- and/or tumor-specific promoters systems have been developed to target cancer cells. This review aims to provide up-to-date information concerning targeting gene therapy with cancer- and/or tumor-specific promoters including cancer suppressor genes, suicide genes, anti-tumor angiogenesis, gene silencing, and gene-editing technology, as well as the type of delivery vehicle employed. Gene therapy can be used to complement traditional therapies to provide more effective treatments.

Synergism of cisplatin-oleanolic acid co-loaded hybrid nanoparticles on gastric carcinoma cells for enhanced apoptosis and reversed multidrug resistance

Combined administration of different drugs is a widely acknowledged approach for effective cancer therapy. However, the limited targeting, as well as inferior drug loading capacities of current drug delivery systems (DDS), are still the bottleneck for better performance in cancer treatment. Herein, we successfully developed a cancer cell membrane (CM) decorated calcium carbonate (CC) hybrid nanoparticles (HN) for the co-delivery of cisplatin (CDDP) and oleanolic acid (OA). The physicochemical property of HN/CDDP/OA was evaluated, which revealed that the as-prepared DDS was core-shell structured and well-dispersed nanoparticles with size around 100 nm. The HN/CDDP/OA showed high stability and biocompatibility with pH-responsive drug release. Moreover, the CM modification in HN also demonstrated highly elevated tumor-homing nature than bare CC. Finally, the feasibility of HN/CDDP/OA in the treatment of gastric cancer (MGC-803 cell line) was assessed. HN/CDDP/OA showed better performance than mono systems with enhanced apoptosis and capable of reversing multidrug resistance (MDR) of cancer cells.

Fibronectin-Targeting and Cathepsin B-Activatable Theranostic Nanoprobe for MR/Fluorescence Imaging and Enhanced Photodynamic Therapy for Triple Negative Breast Cancer

Because of the lack of specific targets, the highly aggressive triple negative breast cancer (TNBC) is unable to benefit from endocrine therapy or conventional targeting therapy. Even worse, current diagnostic and therapeutic approaches have limited value for TNBC. Therefore, developing TNBC-specific theranostic probes for accurate diagnosis and further selective therapy will build a powerful toolbox for TNBC management. In this contribution, we developed a sequential strategy to enhance the specificity of TNBC theranostics. In this theranostic system, a versatile nanoprobe (Pep-SQ@USPIO) was integrated legitimately for the fibronectin-targeting MR imaging and CTSB-activatable fluorescence imaging, followed with enhanced photodynamic therapy (PDT) of TNBC. First, the fibronectin overexpressed in the extracellular matrix (ECM) of TNBC was used as a biomarker for targeting theranostics using the Cys-Arg-Glu-Lys-Ala (CREKA) peptide. For another, the fluorescence and PDT capacity of self-developed squaraine photosensitizer (SQ) were prequenched by ultrasmall superparamagnetic iron oxide (USPIO), an MR imaging contrast agent. Once the linker, Gly-Phe-Leu-Gly (GFLG) peptide, was selectively cleaved by TNBC-derived CTSB, the liberated SQ photosensitizer allowed light-up fluorescence imaging and enhanced PDT of TNBC. Remarkably, this research demonstrates that tumor-ECM-targeting and endogenous enzyme-activated nanoprobes open a new avenue for TNBC theranostics.

Prognosis and targeting of pre-metastatic niche

As the main cause of tumoral fatality, metastasis remains to be one of the most urgent difficulties researcher struggled to overcome. During the development and progression of metastasis, the establishment of pre-metastatic niche is crucial in preparing fertile microenvironment for disseminated tumor cells settlement and colonization in distant metastatic target sites. The key participators, including the primary tumor-derived factors, bone marrow-derived cells, stromal cells of both the host and the potential metastatic sites, regulate the temporal progress of potential metastasis. Firstly, pioneers are sent from primary tumor, recruiting immunosuppressive cells; then circulating tumor cells settled and colonized; and finally, micrometastases develop. Here, we summarize the therapeutic strategies presented in recent years targeting different stages of the pre-metastatic niche formation and discuss their chances and challenges in clinical translation, providing promising approaches for metastasis prevention and therapeutic interventions.

Size-Controlled Preparation and Behavior Study of Phospholipid-Calcium Carbonate Hybrid Nanoparticles

Background

Calcium carbonate (CC) nanoparticles have broad biomedical utilizations, owing to their multiple intrinsic merits. However, bare CC nanoparticles do not allow for the development of multifunctional devices suitable for advanced drug delivery in cancer therapy.

Methods

Phospholipid-modified phospholipid–CC hybrid nanoparticles were prepared in our study using a combination of vapor-diffusion and solvent-diffusion methods to offer optimized pharmaceutical capabilities.

Results

Considering that particle size is a critical parameter that plays an important role in both in vitro and in vivo behaviors of nanoparticles, we here for the first time a present detailed protocol for the size-controlled preparation of hybrid nanoparticles, as well as analysis of the in vitro/in vivo behaviors of differently sized hybrid nanoparticles.

Conclusion

Our results might significantly advance the application of this promising material in more varied fields.

Ca2+ signaling modulation using cancer cell membrane coated chitosan nanoparticles to combat multidrug resistance of cancer

Off-target drug delivery, together with multidrug resistance (MDR), are two keys obstacles that account for the disappointing outcome in clinical chemotherapy of cancer. To solve these dilemmas, Herein, we constructed cancer cell membrane (CCM) modified silica (CS) nanoparticles (CCM/CS) to co-deliver Ca²⁺ channel siRNA with doxorubicin (DOX) to construct a platform (CCM/CS/R-D) for the efficient therapy of cervical cancer. It was demonstrated that the optimal CCM/CS/R-D was spherical nanoparticles with size at 122.39 ± 4.69 nm and the surface charge of -27.76 ± 3.12 mV. In addition, the CCM/CS/R-D showed acid responsive drug release while high stability under physiological conditions with negligible hemolysis. The CCM/CS/R-D showed CCM mediated cellular uptake and efficient endosomal escape as well as siRNA transfection potential (comparable to that of PEI 25 K) on MDR cervical cancer cells (HeLa/DOX). Most importantly, the MDR of cancer cells was conquered through modulation of T-type Ca²⁺ (Cav) channels. It was observed that the Cav channel siRNA could negatively regulate the level of cytosolic Ca²⁺ concentration which triggered G0/G1 phase cell cycle arrest and elevated intracellular drug retention in HeLa/DOX cells without significantly affect the expression of P-glycolprotein (P-gp). The in vitro and in vivo experiments revealed that CCM/CS/R-D exerted greatly enhanced tumor targetability and therapeutic effect on HeLa/DOX, which was superior than CS/R-D or mono delivery system (CCM/CS/R or CCM/CS/D).

Heparin coated meta-organic framework co-delivering doxorubicin and quercetin for effective chemotherapy of lung carcinoma

Objective

To develop and evaluate a drug delivery system (DDS) capable of targeting cancer cells while at the same time delivering two chemotherapeutic agents to overcome multidrug resistance (MDR).

Methods

This study developed a DDS composed of heparin (HA)-coated meta-organic framework (MOF) nanoparticles (HM) designed to deliver doxorubicin (Dox) and quercetin (Que). A range of in vitro and in vivo studies were conducted to determine the characteristics of the HM/Dox/Que nanoparticles, their ability to produce cytotoxic effects in Dox-resistant A549/Dox cells and target and treat solid tumours in a mouse xenograft model of human lung carcinoma.

Results

This study demonstrated that the HM/Dox/Que nanoparticles reduced cell viability, increased apoptosis, arrested cells in the G0/G1 phase of the cell cycle and reversed MDR in A549/Dox cells in vitro when compared with mono-drug delivery. In a mouse xenograft model of human lung carcinoma, the HM/Dox/Que nanoparticles targeted the tumours and reduced tumour growth as determined by tumour volume.

Conclusion

The use of HM/Dox/Que nanoparticles might be a viable alternative to traditional chemotherapy of lung carcinoma.

Cancer Cell Membrane-Decorated Zeolitic-Imidazolate Frameworks Codelivering Cisplatin and Oleanolic Acid Induce Apoptosis and Reversed Multidrug Resistance on Bladder Carcinoma Cells

Combination therapy is emerging as a preferable approach in cancer therapy with minimized side effects and elevated performance. Nevertheless, the poor targeting and drug loading of currently available drug delivery systems (DDSs) are the main difficulties to realize preferable combination therapy of cancer. As a result, a cancer cell membrane-decorated zeolitic-imidazolate framework hybrid nanoparticle (HP) was successfully constructed in our study to codeliver cisplatin (DDP) and oleanolic acid (OLA). Our results showed positive results of the platform (HP/DDP/OLA) for the treatment of bladder cancer (SW780). In detail, HP/DDP/OLA could enhance apoptosis while reverse multidrug resistance in SW780 cells than free drugs alone or monodelivery systems, which might be a suitable DDS for codelivery of different drugs with great promise.

Effective Targeting of Colon Cancer Cells with Piperine Natural Anticancer Prodrug Using Functionalized Clusters of Hydroxyapatite Nanoparticles

Targeted drug delivery offers great opportunities for treating cancer. Here, we developed a novel anticancer targeted delivery system for piperine (Pip), an alkaloid prodrug derived from black pepper that exhibits anticancer effects. The tailored delivery system comprises aggregated hydroxyapatite nanoparticles (HAPs) functionalized with phosphonate groups (HAP-Ps). Pip was loaded into HAPs and HAP-Ps at pH 7.2 and 9.3 to obtain nanoformulations. The nanoformulations were characterized using several techniques and the release kinetics and anticancer effects investigated in vitro. The Pip loading capacity was >20%. Prolonged release was observed with kinetics dependent on pH, surface modification, and coating. The nanoformulations fully inhibited monolayer HCT116 colon cancer cells compared to Caco2 colon cancer and MCF7 breast cancer cells after 72 h, whereas free Pip had a weaker effect. The nanoformulations inhibited ~60% in HCT116 spheroids compared to free Pip. The Pip-loaded nanoparticles were also coated with gum Arabic and functionalized with folic acid as a targeting ligand. These functionalized nanoformulations had the lowest cytotoxicity towards normal WI-38 fibroblast cells. These preliminary findings suggest that the targeted delivery system comprising HAP aggregates loaded with Pip, coated with gum Arabic, and functionalized with folic acid are a potentially efficient agent against colon cancer.

Natural polysaccharide-incorporated hydroxyapatite as size-changeable, nuclear-targeted nanocarrier for efficient cancer therapy

Nuclear-targeted, size-changeable polysaccharide hybrid hydroxyapatite nanoparticles were prepared for the delivery of doxorubicin for cancer therapy, showing low toxicity to healthy tissue cells but strong killing effect on tumor cells.

Nanomedicine in treatment of breast cancer - A challenge to conventional therapy

Amongst the various types of cancer, breast cancer is a highly heterogeneous disease and known as the leading cause of death among women globally. The extensive interdisciplinary investigation in nanotechnology and cancer biomedical research has been evolved over the years for its effective treatment. However, the advent of chemotherapeutic resistance in breast cancer is one of the major confront researchers are facing in achieving successful chemotherapy. Research in the area of cancer nanotechnology over the years have now been revolutionized through the development of smart polymers, lipids, inorganic materials and eventually their surface-engineering with targeting ligands. Moreover, nanotechnology further extended and brings in the notice the new theranostic approach which combining the therapy and imaging simultaneously. Currently, research is being envisaged in the area of novel nano-pharmaceutical design viz. liposome, nanotubes, polymer lipid hybrid system, which focuses to make the chemotherapy curative and long-lasting. In this review, we aimed to discuss the recent advancement of different surface-engineered/targeted nanomedicines that improved the drug efficacy in breast cancer.

Cancer Cell Membrane Decorated Silica Nanoparticle Loaded with miR495 and Doxorubicin to Overcome Drug Resistance for Effective Lung Cancer Therapy

Current cancer therapy usually succumbs to many extracellular and intracellular barriers, among which untargeted distribution and multidrug resistance (MDR) are two important difficulties responsible for poor outcome of many drug delivery systems (DDS). Here, in our study, the dilemma was addressed by developing a cancer cell membrane (CCM)-coated silica (SLI) nanoparticles to co-deliver miR495 with doxorubicin (DOX) for effective therapy of lung cancer (CCM/SLI/R-D). The homologous CCM from MDR lung cancer cells (A549/DOX) was supposed to increase the tumor-homing property of the DDS to bypass the extracellular barriers. Moreover, the MDR of cancer cells were conquered through downregulation of P-glycoprotein (P-gp) expression using miR495. It was proved that miR495 could significantly decrease the expression of P-gp which elevated intracellular drug accumulation in A549/DOX. The in vitro and in vivo results exhibited that CCM/SLI/R-D showed a greatly enhanced therapeutic effect on A549/DOX, which was superior than applying miR495 or DOX alone. The preferable effect of CCM/SLI/R-D on conquering the MDR in lung cancer provides a novel alternative for effective chemotherapy of MDR cancers.

Novel therapeutic interventions in cancer treatment using protein and peptide-based targeted smart systems

Cancer, being the most prevalent and resistant disease afflicting any gender, age or social status, is the ultimate challenge for the scientific community. The new generation therapeutics for cancer management has shifted the approach to personalized/precision medicine, making use of patient- and tumor-specific markers for specifying the targeted therapies for each patient. Peptides targeting these cancer-specific signatures hold enormous potential for cancer therapy and diagnosis. The rapid advancements in the combinatorial peptide libraries served as an impetus to the development of multifunctional peptide-based materials for targeted cancer therapy. The present review outlines benefits and shortcomings of peptides as cancer therapeutics and the potential of peptide modified nanomedicines for targeted delivery of anticancer agents.

Artificial Cell-Mediated Photodynamic Therapy Enhanced Anticancer Efficacy through Combination of Tumor Disruption and Immune Response Stimulation

Recent studies have identified photodynamic therapy (PDT) as a promising approach for cancer treatment. Here, in this study, we have constructed cancer cell membrane (CCM)-coated silica nanoparticles (SIL) as an artificial cell carrier (CCM/SIL) to effectively deliver chlorin e6 (Ce6), a commonly adopted photodynamic reagent (CCM/SIL/Ce6), to achieve enhanced PDT of cancer. In addition, apart from the generally recognized cytotoxicity induced by reactive oxygen species (ROS), our study also revealed that ROS could further potentiate the loss of intercellular junctions and integrity disruption as a result of down-regulation of VE-cadherin and CD31. Consequently, dendritic cells (DCs) were more readily accumulated to the tumor tissue and became maturated, which secreted tumor necrosis factor-α and interleukin-12 (IL-12) to trigger the following immune responses. Our work not only explored the anticancer feasibility of a new system but also demonstrated the underlining mechanisms responsible for PDT-induced anticancer effects, which offers a new perspective to employ and improve the efficacy of PDT and related systems.

Chlorins e6 loaded silica nanoparticles coated with gastric cancer cell membrane for tumor specific photodynamic therapy of gastric cancer

Background: Photodynamic therapy (PDT) is widely recognized as a promising way to cure cancer. However, the limited tumor homing property of currently available drug delivery systems (DDSs) is the bottleneck for the delivery of photodynamic agents. Purpose: In our study, we decorated silica nanoparticles (SLN) with cell membrane (CM) derived from SGC7901 cells to construct carrier (CM/SLN) which was able to to specifically target the homogenous SGC7901 cells. Materials and methods: Furthermore, the decent drug loading capability of CM/SLN was adopted to load photodynamic agent chlorins e6 (Ce6) to finally construct aDDS suitable for tumor-targeted PDT of gastric cancer. Results: The experimental results suggested that CM/SLN/Ce6 was nano-sized particles with good dispersion and stability in physiological conditions. Moreover, due to the modification of CM,CM/SLN/Ce6 could specifically target the homogenous SGC7901 cells both in vitro and in vivo. Most importantly, further in vivo results demonstrated that the CM/SLN/Ce6 showed a better anticancer outcome compared to SLN/Ce6. Conclusion: CM/SLN/Ce6 might be a promising platform for effective tumor targeted PDT of gastric cancer.

Cationic liposome codelivering PI3K pathway regulator improves the response of BRCA1-deficient breast cancer cells to PARP1 inhibition

Although some progresses have been made in breast cancer therapy, effective treatment for BRCA1-deficient breast cancer remains to be a great challenge. It has been demonstrated that the PI3K pathway is inappropriately activated in BRCA1-deficient breast cancers which can be downregulated by microRNA 451 (miR-451). In addition, although PARP1 inhibitors showed relatively positive results in both preclinical and clinical studies, additional efforts to decrease drug resistance as well as reduce systematic toxicity need to be addressed. To this end, by encapsulating the miR-451 mimic and PARP1 inhibitor in the same cationic liposome, we examined the potential of enhancing the response of PARP1 inhibition on BRCA1-deficient breast cancer by regulating the PI3K pathway. Our results revealed that in BRCA1-deficient human breast cancer cell line, PARP1 inhibition resulted in DNA damage with viability decrease, G2/M arrest as well as apoptosis. In contrast, single PI3K inhibition induced G1 arrest along with retarded cell proliferation. However, it was noted that combination of PARP inhibitor and PI3K regulator could exert synergetic function to evidently decrease cell proliferation compared with PARP inhibition alone, which was also confirmed by in vivo antitumor assay using xenograft tumor models. Collectively, our results offer an alternative but superior strategy for the therapy of BRCA1-deficient human breast cancers which may benefit the clinical applications.

pH-activatable polymeric nanodrugs enhanced tumor chemo/antiangiogenic combination therapy through improving targeting drug release

It was widely accepted that polymeric nanodrugs held superiority in enhancing antitumor efficacy, reducing side effect and achieving better long-term prognosis. However, there still existed disputes that whether their therapeutic efficiency was closely related to insure effective release of hydrophobic drug located in their hydrophobic core in tumor site. In order to investigate this controversy, we constructed two polymeric nanodrugs (pH-activatable sLMWH-UOA and non-sensitive LMWH-UOA) with low molecular weight heparin (LMWH) and ursolic acid (UOA) for chemo-and anti-angiogenic combination therapy in hepatocellular carcinoma. The degradation ratio of pH-activatable sLMWH-UOA increased by 33% compared with non-sensitive LMWH-UOA in in vitro degradation study. Besides, confocal microscopy captured that sLMWH-UOA could effectively release drug in acidic microenvironment of lysosome while LMWH-UOA nearly could not. More importantly, in contrast with LMWH-UOA, sLMWH-UOA presented pH-dependent cytotoxicity, indicating that promoting drug release played a key role in enhancing the cytotoxicity of polymeric nanodrugs. Additionally, in vivo pharmacodynamic evaluation showed that although non-sensitive LMWH-UOA had benefited from enhanced tumor targeting drug delivery ability to achieve absolute advantage over free drug combination therapy in antitumor combination therapy, sLMWH-UOA could acquire further optimized combined therapeutic effect with better drug release in tumor. All above, application of tumor-triggered chemical bonds to construct polymeric nanodrugs held vast prospect for improving the therapeutic efficiency for tumor cells.

Folate-modified hydroxyapatite nanorods induce apoptosis in MCF-7 cells through a mitochondrial-dependent pathway

The targeted delivery of therapeutic drugs into cancer cells is a facile method to improve therapeutic efficacy.