Tumor cells-specific targeting delivery achieved by A54 peptide functionalized polymeric micelles

Advances in nanocarriers for targeted drug delivery and controlled drug release

Nanocarrier-based drug delivery systems (nDDSs) present significant opportunities for improving disease treatment, offering advantages in drug encapsulation, solubilization, stability enhancement, and optimized pharmacokinetics and biodistribution. nDDSs, comprising lipid, polymeric, protein, and inorganic nanovehicles, can be guided by or respond to biological cues for precise disease treatment and management. Equipping nanocarriers with tissue/cell-targeted ligands enables effective navigation in complex environments, while functionalization with stimuli-responsive moieties facilitates site-specific controlled release. These strategies enhance drug delivery efficiency, augment therapeutic efficacy, and reduce side effects. This article reviews recent strategies and ongoing advancements in nDDSs for targeted drug delivery and controlled release, examining lesion-targeted nanomedicines through surface modification with small molecules, peptides, antibodies, carbohydrates, or cell membranes, and controlled-release nanocarriers responding to endogenous signals such as pH, redox conditions, enzymes, or external triggers like light, temperature, and magnetism. The article also discusses perspectives on future developments.

Intestinal Absorption of Nanoparticles to Reduce Oxidative Stress and Vasoconstriction for Treating Diabetic Nephropathy

The etiology of diabetic nephropathy (DN) is complex, and the incidence is increasing year by year. The patient's kidney showed oxidative stress damage, increasing active oxygen species (ROS) content, and vasoconstriction. Due to poor drug solubility and low renal accumulation, the current treatment regimens have not effectively alleviated glomerulopathy and other kidney damage caused by DN. Therefore, it is of great significance to explore new treatment strategies and drug delivery systems. Here, we constructed an oral nanodelivery system (Tel/CAN@CS-DA) that reduced oxidative stress and vasoconstriction. Deoxycholic acid (DA)-modified nanoparticles entered into intestinal epithelial cells (Caco2 cells) via the bile acid biomimetic pathway, then escaped from the lysosomes and eventually spat out the cells, increasing the oral absorption of nanoparticles. Chitosan (CS) nanoparticles could achieve renal targeting through specific binding with a renal giant protein receptor and deliver drugs to renal tubule epithelial cells (HK-2 cells). In vitro studies also proved that telmisartan (Tel) and canagliflozin (CAN) effectively removed cellular reactive oxygen species (ROS) and reduced HK-2 cell apoptosis caused by high glucose. In the in vivo model induced by streptozotocin (STZ), the results showed that the nanosystem not only elevated AMPK protein expression, inhibited angiotensin II (Ang II) protein expression to effectively reduce oxidative stress level, dilated renal blood vessels but also reduced the degree of inflammation and fibrosis. Overall, Tel/CAN@CS-DA multifunctional oral nanosystem can effectively treat DN with low toxicity, which provides a new idea for the treatment of DN.

Smart nanoparticles for cancer therapy

Smart nanoparticles, which can respond to biological cues or be guided by them, are emerging as a promising drug delivery platform for precise cancer treatment. The field of oncology, nanotechnology, and biomedicine has witnessed rapid progress, leading to innovative developments in smart nanoparticles for safer and more effective cancer therapy. In this review, we will highlight recent advancements in smart nanoparticles, including polymeric nanoparticles, dendrimers, micelles, liposomes, protein nanoparticles, cell membrane nanoparticles, mesoporous silica nanoparticles, gold nanoparticles, iron oxide nanoparticles, quantum dots, carbon nanotubes, black phosphorus, MOF nanoparticles, and others. We will focus on their classification, structures, synthesis, and intelligent features. These smart nanoparticles possess the ability to respond to various external and internal stimuli, such as enzymes, pH, temperature, optics, and magnetism, making them intelligent systems. Additionally, this review will explore the latest studies on tumor targeting by functionalizing the surfaces of smart nanoparticles with tumor-specific ligands like antibodies, peptides, transferrin, and folic acid. We will also summarize different types of drug delivery options, including small molecules, peptides, proteins, nucleic acids, and even living cells, for their potential use in cancer therapy. While the potential of smart nanoparticles is promising, we will also acknowledge the challenges and clinical prospects associated with their use. Finally, we will propose a blueprint that involves the use of artificial intelligence-powered nanoparticles in cancer treatment applications. By harnessing the potential of smart nanoparticles, this review aims to usher in a new era of precise and personalized cancer therapy, providing patients with individualized treatment options.

Combination therapy based on dual-target biomimetic nano-delivery system for overcoming cisplatin resistance in hepatocellular carcinoma

Strategies to overcome toxicity and drug resistance caused by chemotherapeutic drugs for targeted therapy against hepatocellular carcinoma (HCC) are urgently needed. Previous studies revealed that high oxidored-nitro domain-containing protein 1(NOR1) expression in HCC was associated with cisplatin (DDP) resistance. Herein, a novel dual-targeting nanocarrier system AR-NADR was generated for the treatment of DDP resistance in HCC. The core of the nanocarrier system is the metal-organic frameworks (MOF) modified with nuclear location sequence (NLS), which loading with DDP and NOR1 shRNA (R). The shell is an A54 peptide inserted into the erythrocyte membrane (AR). Our results show that AR-NADR efficiently internalized by tumor cells due to its specific binding to the A54 receptors that are abundantly expressed on the surface of HCC cells and NLS peptide-mediated nuclear entry. Additionally, DDP is more likely to be released due to the degradation of Ag-MOF in the acidic tumor microenvironment. Moreover, by acting as a vector for gene delivery, AR-NADR effectively inhibits tumor drug resistance by suppressing the expression of NOR1, which induces intracellular DDP accumulation and makes cells sensitive to DDP. Finally, the anti-HCC efficacy and mechanisms of AR-NADR were systematically elucidated by a HepG2/DDP cell model as well as a tumor model. Therefore, AR-NADR constitutes a key strategy to achieve excellent gene silencing and antitumor efficacy, which provides effective gene therapy and precise treatment strategies for cisplatin resistance in HCC.

Glycosylation and its research progress in endometrial cancer

Endometrial cancer (EC) is one of the most common tumors in the female reproductive system, which seriously threatens women's health, particularly in developed countries. 13% of the patients with EC have a poor prognosis due to recurrence and metastasis. Therefore, identifying good predictive biomarkers and therapeutic targets is critical to enable the early detection of metastasis and improve the prognosis. For decades, extensive studies had focused on glycans and glycoproteins in the progression of cancer. The types of glycans that are covalently attached to the polypeptide backbone, usually via nitrogen or oxygen linkages, are known as N‑glycans or O‑glycans, respectively. The degree of protein glycosylation and the aberrant changes in the carbohydrate structures have been implicated in the extent of tumorigenesis and reported to play a critical role in regulating tumor invasion, metabolism, and immunity. This review summarizes the essential biological role of glycosylation in EC, with a focus on the recent advances in glycomics and glycosylation markers, highlighting their implications in the diagnosis and treatment of EC.

Developing Smart Nanoparticles Responsive to the Tumor Micro-Environment for Enhanced Synergism of Thermo-Chemotherapy With PA/MR Bimodal Imaging

With the development of nanotechnology, a theranostics nanoplatform can have broad applications in multimodal image-guided combination treatment in cancer precision medicine. To overcome the limitations of a single diagnostic imaging mode and a single chemotherapeutic approach, we intend to combat tumor growth and provide therapeutic interventions by integrating multimodal imaging capabilities and effective combination therapies on an advanced platform. So, we have constructed IO@MnO₂@DOX (IMD) hybrid nanoparticles composed of superparamagnetic iron oxide (IO), manganese dioxide (MnO₂), and doxorubicin (DOX). The nano-platform could achieve efficient T2-T1 magnetic resonance (MR) imaging, switchable photoacoustic (PA) imaging, and tumor microenvironment (TME)-responsive DOX release and achieve enhanced synergism of magnetic hyperthermia and chemotherapy with PA/MR bimodal imaging. The results show that IMD has excellent heating properties when exposed to an alternating magnetic field (AMF). Therefore, it can be used as an inducer for tumor synergism therapy with chemotherapy and hyperthermia. In the TME, the IMD nanoparticle was degraded, accompanied by DOX release. Moreover, in vivo experimental results show that the smart nanoparticles had excellent T2-T1 MR and PA imaging capabilities and an excellent synergistic effect of magnetic hyperthermia and chemotherapy. IMD nanoparticles could significantly inhibit tumor growth in tumor-bearing mice with negligible side effects. In conclusion, smart IMD nanoparticles have the potential for tumor diagnosis and growth inhibition as integrated diagnostic nanoprobes.

GRP78-targeted and doxorubicin-loaded nanodroplets combined with ultrasound: a potential novel theranostics for castration-resistant prostate cancer

The construction of multifunctional oncotherapy nanoplatforms that combine diagnosis and treatment remains challenging. Nanodroplets (NDs), which simultaneously enhance ultrasound imaging and therapeutic effects, are a potential strategy for non-invasive drug delivery. To achieve the goals of precise medicine, novel SP94 peptide-modified and doxorubicin-loaded ultrasonic NDs (SP94-DOX-NDs) for castration-resistant prostate cancer (CRPC) targeting and treatment were constructed in this study. The characteristics, contrast-enhanced ultrasound imaging (CEUI), targeting ability to glucose-regulated protein 78 (GRP78)-overexpressing CRPC and anticancer effect of the SP94-DOX-NDs were assessed. The desired SP94-NDs were successfully prepared using the nanoemulsification method using a certain proportion of SP94-PEG-chitosan, perfluoropentane (PFP), Tween 20, and lecithin. SP94-NDs with a size of ∼300 nm showed great biocompatibility and CEUI ability. Compared with blank NDs, SP94-NDs exhibited higher tumor-specific targeting ability due to conjugation between the SP94 peptide and GRP78-overexpressing 22RV1 cells. Most importantly, in vitro and in vivo investigations showed that SP94-DOX-NDs combined with ultrasound could specifically deliver DOX into 22RV1 cells and thereby demonstrated a stronger anticancer effect than DOX-NDs and DOX. Thus, SP94-DOX-NDs may provide an efficient approach for the real-time imaging of tumors and triggered, accurate drug delivery to tumors.

Aptamer and Peptide-Modified Lipid-Based Drug Delivery Systems in Application of Combined Sequential Therapy of Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is known as the most common malignancy of the hepatobiliary system with a continued increase in incidence but limited therapeutic options. Nanomedicine has provided a promising strategy through engineered nanocarriers that are capable of targeting therapeutic agents specifically to tumor cells. In this research, two aptamer/peptide-modified lipid-based drug delivery systems (A54-PEG-SLN/OXA and A15-PEG-SLN/SAL) were developed as a sequential therapeutic strategy to conquer specific hepatocellular carcinoma. The nanomedicine A54-PEG-SLN/OXA was able to target specific hepatocellular carcinoma cell BEL-7402 and exhibited a strong targeting ability and antitumor efficiency both in vitro and in vivo. The A15-PEG-SLN/SAL could target and penetrate deeply to the spheroid composed of CD133+ cancer cells. In the study of developing a sequential therapeutic strategy, we demonstrated that A54-PEG-SLN/OXA could kill tumor cells and expose CD133+ cancer cells. After the administration of A15-PEG-SLN/SAL, the growth of the tumors was significantly inhibited. In conclusion, the aptamer/peptide-modified lipid-based drug delivery systems, A54-PEG-SLN/OXA and A15-PEG-SLN/SAL, could specifically target carcinoma cells and had an evident antitumor effect when administrated sequentially.

Radiolabeled Peptide Probes for Liver Cancer Imaging

Liver cancer/Hepatocellular Carcinoma (HCC) is a leading cause of cancer death and represents an important cause of mortality worldwide. Several biomarkers are overexpressed in liver cancer, such as Glypican 3 (GPC3) and Epidermal Growth Factor Receptor (EGFR). These biomarkers play important roles in the progression of tumors and could serve as imaging and therapeutic targets for this disease. Peptides with adequate stability, receptor binding properties, and biokinetic behavior have been intensively studied for liver cancer imaging. A great variety of them have been radiolabeled with clinically relevant radionuclides for liver cancer diagnosis, and many are promising imaging and therapeutic candidates for clinical translation. Herein, we summarize the advancement of radiolabeled peptides for the targeted imaging of liver cancer.

Gadolinium-loaded calcium phosphate nanoparticles for magnetic resonance imaging of orthotopic hepatocarcinoma and primary hepatocellular carcinoma

The development of magnetic resonance imaging (MRI) contrast agents with high sensitivity and good biocompatibility is of great value for the diagnosis of primary hepatocellular carcinoma (HCC). Here, a novel MRI contrast agent based on calcium phosphate (CaP) nanoparticles modified with a liver cancer cell targeting peptide A54 (A54-CaP) was fabricated. The T1-positive contrast agent Gd-DTPA was encapsulated inside the nanoparticles (A54-CaPNPs), with a mean diameter of 30 nm and a high encapsulation efficiency of 92.73%. The A54-CaPNP solution exhibited higher longitudinal relaxivity (6.07 mM-1 s-1) than that of the clinically used MRI contrast agent Gd-DTPA (3.56 mM-1 s-1). A much higher accumulation of the nanoparticles in the liver cells was observed, which was directed by the A54 targeting peptide. Furthermore, the MRI diagnostic efficiency of A54-CaPNPs was systematically investigated in an orthotopic liver cancer model and primary HCC model. In vivo MRI experiments showed that A54-CaPNPs had higher sensitivity in the BEL-7402 orthotopic liver cancer model with a more remarkable contrast enhancement and a longer imaging time compared to those without A54 modification. Moreover, the experiments on primary HCC models suggested that A54-CaPNPs showed greatly enhanced MR imaging performance in comparison with Gd-DTPA. These results suggest that A54-CaPNPs possess great potential to enable the non-invasive early diagnosis of primary HCC for timely surgical resection.

Enhancing Drug Delivery for Overcoming Angiogenesis and Improving the Phototherapy Efficacy of Glioblastoma by ICG-Loaded Glycolipid-Like Micelles

Background

Phototherapy is a potential new candidate for glioblastoma (GBM) treatment. However inadequate phototherapy due to stability of the photosensitizer and low target specificity induces the proliferation of neovascular endothelial cells for angiogenesis and causes poor prognosis.

Methods

In this study, we constructed c(RGDfk)-modified glycolipid-like micelles (cRGD-CSOSA) encapsulating indocyanine green (ICG) for dual-targeting neovascular endothelial cells and tumor cells, and cRGD-CSOSA/ICG mediated dual effect of PDT/PTT with NIR irradiation.

Results

In vitro, cRGD-CSOSA/ICG inhibited cell proliferation and blocked angiogenesis with NIR irradiation. In vivo, cRGD-CSOSA/ICG exhibited increased accumulation in neovascular endothelial cells and tumor cells. Compared with that of CSOSA, the accumulation of cRGD-CSOSA in tumor tissue was further improved after dual-targeted phototherapy pretreatment. With NIR irradiation, the tumor-inhibition rate of cRGD-CSOSA/ICG was 80.00%, significantly higher than that of ICG (9.08%) and CSOSA/ICG (42.42%). Histological evaluation showed that the tumor vessels were reduced and that the apoptosis of tumor cells increased in the cRGD-CSOSA/ICG group with NIR irradiation.

Conclusion

The cRGD-CSOSA/ICG nanoparticle-mediated dual-targeting phototherapy could enhance drug delivery to neovascular endothelial cells and tumor cells for anti-angiogenesis and improve the phototherapy effect of glioblastoma, providing a new strategy for glioblastoma treatment.

Micelles modified with a chitosan-derived homing peptide for targeted intracellular delivery of ginsenoside compound K to liver cancer cells

Ginsenoside compound K (CK), a major metabolite of protopanaxadiol ginsenosides, exhibits significant anticancer activities against various cancer cells. However, CK has poor water solubility and low bioavailability, which have limited its application. In this study, A54 peptide was utilized to fabricate CK-loaded micelles (APD-CK) for liver targeting, using deoxycholic acid-O-carboxymethyl chitosan as the vehicle. The average particle size of APD-CK micelles was about 171.4 nm by dynamic light scattering in the hydrated state and their morphology were spherical with good dispersion. An in vitro release assay indicated pH-responsive and sustained release behavior through a mechanism of non-Fickian diffusion. Moreover, the in vitro cytotoxicity of the APD-CK micelles against HepG2 and Huh-7 cells was significantly stronger than that of CK up to 20 μg/mL. Enhanced cellular uptake of micelles in both cell types was established using confocal fluorescence scanning microscopy and flow cytometry. In addition, western blot analysis revealed that APD-CK micelles could promote the protein expression levels of caspase-3, caspase-9, and poly (ADP-ribose) polymerase. Therefore, APD-CK micelles are a potential vehicle for delivering hydrophobic drugs in liver cancer therapy, enhancing drug targeting and anticancer activity.

In vivoprogramming of tumor mitochondria-specific doxorubicin delivery by a cationic glycolipid polymer for enhanced antitumor activity

C-P-CSOSA/DOX exhibited effective mitochondria-targeted capabilityin vitroandin vivo, based on a skeletal polymer with cationic and lipophilic character.

A multifunctional near-infrared laser-triggered drug delivery system using folic acid conjugated chitosan oligosaccharide encapsulated gold nanorods for targeted chemo-photothermal therapy

FA–COS–TGA–GNRs–DOX have been successfully designed as a drug delivery system for chemo-photothermal combination therapy.

N-(2-Hydroxy)-propyl-3-trimethylammonium, O-Mysristoyl Chitosan Enhances the Solubility and Intestinal Permeability of Anticancer Curcumin

An amphiphilic derivative of chitosan containing quaternary ammonium and myristoyl groups, herein named as ammonium myristoyl chitosan (DMCat), was synthesized by reacting glycidyltrimethylammonium chloride (GTMAC) and myristoyl chitosan (DMCh). The success of the modification was confirmed using Fourier-transform infrared spectroscopy (FTIR) and ¹H nuclear magnetic resonance (NMR) spectroscopy. The average degrees of alkylation and quaternization (DQ¯) were determined by using ¹H NMR and conductometric titration. The zeta potential of the micelles was higher than 28 mV while its average size and encapsulation efficiency ranged from 280 nm to 375 nm and 68% to 100%, respectively. The in vitro cytotoxicity of the unloaded and curcumin (CUR)-loaded micelles was tested against Caco-2 and HT29-MTX intestinal epithelial cell lines. The results showed no cytotoxic effect from loaded and unloaded micelles as compared to free CUR. In the permeability test, it was observed that both types of micelles, i.e., DMCh and DMCat, improved CUR permeability. Additionally, higher permeability was verified for both systems in Caco-2/HT29-MTX:Raji B because of the mucoadhesive character of chitosan and its ability to open tight junctions. The results indicated that DMCat micelles, due to the physico-chemical, improved characteristics may be a promising carrier to encapsulate CUR aiming cancer therapy.

SPIO-loaded nanostructured lipid carriers as liver-targeted molecular T2-weighted MRI contrast agent

Background

Superparamagnetic iron oxide (SPIO) acts as a negative contrast agent in magnetic resonance imaging (MRI), and is widely used in clinical applications, including the diagnosis of hepatic diseases. Hepatocyte-targeted magnetic resonance contrast agents (MRCAs) can provide useful information for evaluating hepatic diseases. We prepared targeted magnetic nanostructured lipid carriers (MNLCs) to enhance the hepatocytes targeting efficiency.

Methods

In vitro characterizations of MNLCs were determined by transmission electron microscopy (TEM). The cytotoxicity assay of the MNLCs was measured by methyl tetrazolium (MTT) method. The uptaken study was measured by confocal microscopy, flow cytometry and MRI in vitro. The enhanced liver-targeting efficiency of MNLCs was measured by fluorescence imaging and MRI in vivo.

Results

Gal-NLC-SPIO was prepared successfully. The cytotoxicity assay of the MNLCs demonstrated that the MNLC had relatively low cytotoxicity and high biocompatibility for LO2 cells. More importantly, we confirmed that Gal-NLC-SPIO had greater uptake by LO2 cells than Gal-NLC-SPIO/PEG and free Gal in vitro. A liver distribution study of MNLCs in normal mice demonstrated that the fluorescent signal values to livers of the Gal-NLC-SPIO were significantly stronger than those of NLC-SPIO and Gal-NLC-SPIO/PEG. The liver targeting efficiency of Gal-NLC-SPIO was confirmed both in vitro and in vivo.

Conclusions

We successfully developed liver-targeting MNLCs, which showed accurate hepatocytes targeting, and thus have the potential to be a new MRI contrast agent to help the diagnosis of liver diseases.

Immune Adjuvant Targeting Micelles Allow Efficient Dendritic Cell Migration to Lymph Nodes for Enhanced Cellular Immunity

Cellular immunity is essential for the effectiveness of vaccines against cancer. After capture of vaccines, dendritic cells (DCs) have to migrate to lymph nodes via chemokine receptor type 7 (CCR7). Subsequently, DCs present cytosolic antigens via major histocompatibility complex class I (MHC I) molecules to induce cellular immunity. However, various vaccines fail to induce potent cellular immunity due to insufficient MHC I-restricted antigen presentation and limitations of immune adjuvants. Hence, we constructed novel immune adjuvant targeting micelles (M-COSA) to targeted codeliver antigen ovalbumin (OVA) and plasmid DNA encoding CCR7 (CCR7 pDNA) to the cytosol of DCs, thus promoting DC migration to lymph nodes to boost MHC I-restricted antigen presentation. M-COSA exhibited adjuvant activity and demonstrated more efficient DC cellular uptake compared with COSA. M-COSA/OVA/pDNA increased costimulatory molecule expression and cytokine secretion, resulting in DC activation and maturation. Moreover, antigens and pDNA, which were encapsulated in micelles, escaped from the endosome into the cytoplasm to achieve MHC I-restricted antigen presentation and increase CCR7 expression. The number of CD8⁺ T cells, which was positively correlated with tumor rejection, was notably increased and tumor growth was dramatically suppressed after vaccination with M-COSA/OVA/pDNA. In summary, M-COSA/OVA/pDNA micelles, which allow DC targeting and efficient DC migration to lymph nodes to enhance cellular immunity, exhibit effective tumor inhibition and lay the foundation for novel vaccine design.

Simultaneous targeting therapy for lung metastasis and breast tumor by blocking the NF-κB signaling pathway using Celastrol-loaded micelles

Metastasis is one of the major obstacles for successful therapy of breast tumor. To inhibit the metastasis and growth of breast tumor simultaneously, a Celastrol (Cela) loaded glucolipid-like conjugates (CSOSA/Cela) with αvβ3-ligand Tetraiodothyroacetic acid (TET) modification (TET-CSOSA/Cela) were established to block nuclear factor-kappa B (NF-κB) signaling pathway. The distribution of TET-CSOSA was remarkably increased in lung metastasis and primary tumor of 4T1 tumor-bearing mice by means of αvβ3 receptor-mediated interaction. The results demonstrated that TET-CSOSA/Cela significantly suppressed Bcl-2 activation of lung metastatic cells and reduced MMP-9 expression of 4T1 breast tumor cells by blocking NF-κB. The inhibitory rates of TET-CSOSA/Cela against lung metastasis and primary tumor were raised to 90.72 and 81.15%, compared to those of Celastrol (72.15 and 46.40%), respectively. All results demonstrated the αvβ3 receptor targeted TET-CSOSA/Cela micelles exhibited great potential in treating lung metastasis and primary tumor simultaneously via blocking NF-κB signaling pathway.

Visual targeted therapy of hepatic cancer using homing peptide modified calcium phosphate nanoparticles loading doxorubicin guided by T1 weighted MRI

Effective treatment and real-time monitoring of hepatic cancer are essential. A multifunctional calcium phosphate nanoparticles loading chemotherapeutic agent doxorubicin and magnetic resonance imaging contrast agent diethylenetriaminepentaacetic acid gadolinium (A54-CaP/Gd-DTPA/DOX) was developed for visual targeted therapy of hepatic cancer via T1-weighted MRI in real-time. A54-CaP/Gd-DTPA/DOX exhibited a higher longitudinal relaxivity (6.02 mM^-1 s^-1) than commercial MR contrast agent Gd-DTPA (3.3765 mM^-1 s^-1). The DOX release from the nanoparticles exhibited a pH dependent behavior. The cellular uptake results showed that the internalization of A54-CaP/Gd-DTPA/DOX into BEL-7402 cells was1.9-fold faster than that of HepG2 cells via A54 binding. In vivo experiments presented that A54-CaP/Gd-DTPA/DOX had higher distribution and longer retention time in tumor tissue than CaP/Gd-DTPA/DOX and free DOX, and also displayed great antitumor efficacy (95.38% tumor inhibition rate) and lower toxicity. Furthermore, the Gd-DTPA entrapped in the nanoparticles could provide T1-weighted MRI for real-time monitoring the progress of tumor treatment.

Targeting High Expressed α5β1 Integrin in Liver Metastatic Lesions To Resist Metastasis of Colorectal Cancer by RPM Peptide-Modified Chitosan-Stearic Micelles

Liver metastasis is a leading death cause in colorectal cancer. The pathological differences between orthotopic tumors and metastatic lesions increased the therapeutic difficulty of metastasis. Herein, the α₅β₁ integrin receptor expression on metastatic cells was first measured, the result showed that metastatic cells expressed the α₅β₁ integrin higher than that of the original cells from orthotopic tumors. Afterward, RPM peptide-modified chitosan-stearic (RPM-CSOSA) was designed based on α₅β₁ integrin expression. The cytotoxicity and resistance to migration and the invasion ability of the targeting drug delivery system loading doxorubicin (DOX) and curcumin (CUR) were evaluated in vitro. The metastatic inhibition of the targeting drug delivery system was also investigated in HT29 liver metastatic models. The modified RPM peptide could increase the cellular internalization of CSOSA micelles in metastatic tumor cells and endothelial cells mediated by α₅β₁ integrin. The synergistic effects of RPM-CSOSA/DOX and RPM-CSOSA/CUR could obviously inhibit migratory and invasive abilities of HT29 cells and endothelial cells. Moreover, the RPM-CSOSA/DOX&RPM-CSOSA/CUR could obviously decrease the number of metastatic sites by 86.96%, while CSOSA/DOX&CSOSA/CUR decreased liver metastasis by 66.58% compared with that in the saline group. In conclusion, the RPM peptide-modified drug delivery system may provide insights into targeting the metastatic cells overexpressing the α₅β₁ integrin, and it has the potential to inhibit liver metastasis of colorectal cancer.

Enhanced Synergism of Thermo-chemotherapy For Liver Cancer with Magnetothermally Responsive Nanocarriers

A combination of magnetic hyperthermia and magnetothermally-facilitated drug release system was developed as a promising strategy for liver cancer therapy. The thermosensitive copolymer, 6sPCL-b-P(MEO2MA-co-OEGMA) shows a good temperature-controlled drug release response. Mn-Zn ferrite magnetic nanoparticles (MZF-MNPs) exhibit a strong magnetic thermal effect with an alternating magnetic field (AMF). Owing to its high magnetic sensitivity, the magnetothermally-responsive nanocarrier/doxorubicin (MTRN/DOX) can be concentrated in the tumor site efficiently through magnetic targeting. Given this information, we synthesized MTRN/DOX which was composed of MZF-MNPs, thermosensitive copolymer drug carriers, and the chemotherapeutic drug---DOX, to study its anticancer effects both in vitro and in vivo.METHODS: MTRN/DOX was designed and prepared. Firstly, we investigated the accumulation effects of MTRN/DOX by Prussian blue staining, transmission electron microscopy (TEM), laser scanning confocal microscopy (LSCM) and conducted 7.0 T MRI. Following this, the magnetothermal effects of MTRN/DOX were studied using an infrared thermal camera. DOX uptake, distribution, and retention in tumor cells and the distribution of MTRN/DOX in vivo were then analyzed via LSCM, flow cytometry and live fluorescence imaging. Lastly, its anticancer effects were evaluated by MTT, AM/PI staining, Annexin-VFITC/PI staining and comparison of relative tumor volume. RESULTS: We found that MTRN/DOX can be efficiently concentrated in the tumor site through magnetic targeting, increasing the uptake of DOX by tumor cells, and prolonging the retention time of the drug within the tumors. MTRN/DOX showed good magnetothermal effects both in vitro and in vivo. Based on the above results, MTRN/DOX had significant anticancer effects. CONCLUSIONS: MTRN/DOX causes temporal-spatial synchronism of thermo-chemotherapy and together with chemotherapeutic drugs, produces a synergistic effect, which enhances the sensitivity of tumor cells to DOX and reduces their side effects.

T2-Weighted Magnetic Resonance Imaging of Hepatic Tumor Guided by SPIO-Loaded Nanostructured Lipid Carriers and Ferritin Reporter Genes

Nowadays, there is a high demand for supersensitive contrast agents for the early diagnostics of hepatocarcinoma. It has been recognized that accurate imaging information is able to be achieved by constructing hepatic tumor specific targeting probes, though it still faces challenges. Here, a AGKGTPSLETTP peptide (A54)-functionalized superparamagnetic iron oxide (SPIO)-loaded nanostructured lipid carrier (A54-SNLC), which can be specifically uptaken by hepatoma carcinoma cell (Bel-7402) and exhibited ultralow imaging signal intensity with varied Fe concentration on T2-weighted imaging (T2WI), was first prepared as an effective gene carrier. Then, an endogenous ferritin reporter gene for magnetic resonance imaging (MRI) with tumor-specific promoter (AFP-promoter) was designed, which can also exhibit a decrease in signal intensity on T2WI. At last, using protamine as a cationic mediator, novel ternary nanoparticle of A54-SNLC/protamine/DNA (A54-SNPD) as an active dual-target T2-weighted MRI contrast agent for imaging hepatic tumor was achieved. Owing to the synergistic effect of A54-SNLC and AFP-promoted DNA targeting with Bel-7402 cells, T2 imaging intensity values of hepatic tumors were successfully decreased via the T2 contrast enhancement of ternary nanoparticles. It is emphasized that the novel A54-SNPD ternary nanoparticle as active dual-target T2-weighted MRI contrast agent were able to greatly increase the diagnostic sensitivity and specificity of hepatic cancer.

Endogenous Polysialic Acid Based Micelles for Calmodulin Antagonist Delivery against Vascular Dementia

Clinical treatment for vascular dementia still remains a challenge mainly due to the blood-brain barrier (BBB). Here, a micelle based on polysialic acid (PSA), which is a hydrophilic and endogenous carbohydrate polymer, was designed to deliver calmodulin antagonist for therapy of vascular dementia. PSA was first chemically conjugated with octadecylamine (ODA), and the obtained PSA-ODA copolymer could self-assemble into micelle in aqueous solution with a 120.0 μg/mL critical micelle concentration. The calmodulin antagonist loaded PSA-ODA micelle, featuring sustained drug release behavior over a period of 72 h with a 3.6% (w/w) drug content and a 107.0 ± 4.0 nm size was then fabricated. The PSA-ODA micelle could cross the BBB mainly via active endocytosis by brain endothelial cells followed by transcytosis. In a water maze test for spatial learning, calmodulin antagonist loaded PSA-ODA micelle significantly reduced the escape latencies of right unilateral common carotid arteries occlusion (rUCCAO) mice with dosage significantly reduced versus free drug. The decrease of hippocampal phospho-CaMKII (Thr286/287) and phospho-synapsin I (Ser603) was partially restored in rUCCAO mice following calmodulin antagonist loaded PSA-ODA micelle treatment. Consistent with the restored CaMKII phosphorylation, the elevation of BrdU/NeuN double-positive cells in the same context was also observed. Overall, the PSA-ODA micelle developed from the endogenous material might promote the development of therapeutic approaches for improving the efficacy of brain-targeted drug delivery and have great potential for vascular dementia treatment.

A54 Peptide Modified and Redox-Responsive Glucolipid Conjugate Micelles for Intracellular Delivery of Doxorubicin in Hepatocarcinoma Therapy

Redox-responsive nanomaterials applied in drug delivery systems (DDS) have attracted an increasing attention in pharmaceutical research as a carrier for antitumor therapy. However, there would be unwanted drug release from a redox-responsive DDS with no selection at nontarget sites, leading to undesirable toxicities in normal tissues and cells. Here, an A54 peptide modified and PEGylated reduction cleavable glucolipid conjugate (A54-PEG-CSO-ss-SA, abbreviated to APC_ssA) was designed for intracellular delivery of doxorubicin (DOX). The synthesized APC_ssA could be assembled via micellization self-assembly in aqueous water above the critical micelle concentration (54.9 μg/mL) and exhibited a high drug encapsulation efficiency (77.92%). The APC_ssA micelles showed an enhanced redox sensitivity in that the disulfide bond could be degraded quickly and the drug would be released from micelles in 10 mM levels of glutathione (GSH). The cellular uptake studies highlighted the affinity of APC_ssA micelles toward the hepatoma cells (BEL-7402) compared to that toward HepG2 cells. In contrast with the nonresponsive conjugate, the drug was released from APC_ssA micelles more quickly in 10 mM level of GSH concentration (tumor cells). Moreover, the DOX-loaded APC_ssA micelles displayed an increased cytotoxicity which was 1.6- to 2.0-fold that of unmodified and nonresponsive micelles. In vivo, the APC_ssA micelles had stronger distribution to liver and hepatoma tissue and prolonged the circulation and retention time, while the drug release only occurred in the tumor tissue. The APC_ssA/DOX showed the tumor inhibition rate equal to that of commercial doxorubicin hydrochloric without negative consequence. This study suggested that the APC_ssA/DOX showed promising potential to treat the tumor for its special tumor targeting, selective intracellular drug release, enhanced antitumor activity, and reduced toxicity on normal tissues.

Multifunctional SPIO/DOX-loaded A54 Homing Peptide Functionalized Dextran-g-PLGA Micelles for Tumor Therapy and MR Imaging

Specific delivery of chemotherapy drugs and magnetic resonance imaging (MRI) contrast agent into tumor cells is one of the issues to highly efficient tumor targeting therapy and magnetic resonance imaging. Here, A54 peptide-functionalized poly(lactic-co-glycolic acid)-grafted dextran (A54-Dex-PLGA) was synthesized. The synthesized A54-Dex-PLGA could self-assemble to form micelles with a low critical micelle concentration of 22.51 μg. mL⁻¹ and diameter of about 50 nm. The synthetic A54-Dex-PLGA micelles can encapsulate doxorubicin (DOX) as a model anti-tumor drug and superparamagnetic iron oxide (SPIO) as a contrast agent for MRI. The drug-encapsulation efficiency was about 80% and the in vitro DOX release was prolonged to 72 hours. The DOX/SPIO-loaded micelles could specifically target BEL-7402 cell line. In vitro MRI results also proved the specific binding ability of A54-Dex-PLGA/DOX/SPIO micelles to hepatoma cell BEL-7402. The in vivo MR imaging experiments using a BEL-7402 orthotopic implantation model further validated the targeting effect of DOX/SPIO-loaded micelles. In vitro and in vivo anti-tumor activities results showed that A54-Dex-PLGA/DOX/SPIO micelles revealed better therapeutic effects compared with Dex-PLGA/DOX/SPIO micelles and reduced toxicity compared with commercial adriamycin injection.

Synthesis and biological application of BKT-140 peptide modified polymer micelles for treating tumor metastasis with an enhanced cell internalization

A modification of CSOSA micelles with BKT-140 increased receptor-mediated cell uptake and anti-metastasis effect in the CXCR4 high expressing cells.

Hybrid polymer micelles capable of cRGD targeting and pH-triggered surface charge conversion for tumor selective accumulation and promoted uptake

This study presents both tumor-targeting ligands (cRGD) and pH-activated surface charge-conversional moiety (imidazole) decorated micelles for Dox delivery. cRGD is expected to induce preferential tumor accumulation, while imidazole switches on positive charge in a tumor acid environment, which leads to enhanced micelle uptake by tumor cells.

β-Ga2O3:Cr(3+) nanoparticle: A new platform with near infrared photoluminescence for drug targeting delivery and bio-imaging simultaneously

Multifunctional nanoparticles which integrate the therapeutic agents and bio-imaging agents into one carrier are emerging as a promising therapeutic platform. Herein, GaOOH:Cr(3+) was firstly synthesized using improved hydrothermal method (atmospheric pressure, 95 °C), and by manipulating the pH of the reaction medium, GaOOH:Cr(3+) with different sizes (125.70 nm, 200.60 nm and 313.90 nm) were synthesized. Then β-Ga2O3:Cr(3+) nanoparticles with porous structures were developed as a result of the calcination of GaOOH:Cr(3+). The fabricated, porous β-Ga2O3:Cr(3+) nanoparticles could effectively absorb doxorubicin hydrochloride (DOX) (loading rate: 8% approximately) and had near infrared photoluminescence with a 695 nm emission. Furthermore, β-Ga2O3:Cr(3+) nanoparticles were coated with l-Cys modified hyaluronic acid (HA-Cys) by exploiting the electrostatic interaction and the cross-link effect of disulfide bond to improve the stability. The DOX loaded HA-Cys coated β-Ga2O3:Cr(3+) nanoparticles (HA/β-Ga2O3:Cr(3+)/DOX) showed an oxidation-reduction sensitive drug release behavior. The HA-Cys coated β-Ga2O3:Cr(3+) nanoparticles showed a low cytotoxicity on MCF-7 and Hela cell lines. The cellular uptake of HA/β-Ga2O3:Cr(3+)/DOX using the near infrared photoluminescence of β-Ga2O3:Cr(3+) nanoparticles and the fluorescence of DOX demonstrated the HA/β-Ga2O3:Cr(3+)/DOX could internalize into tumor cells quickly, which was affected by the size and shape of β-Ga2O3:Cr(3+)nanoparticles.

In vivo pharmacokinetics, biodistribution and antitumor effect of paclitaxel-loaded micelles based on α-tocopherol succinate-modified chitosan

In our previous study, α-tocopherol succinate modified chitosan (CS-TOS) was synthesized and encapsulated paclitaxel (PTX) to form micelles. Preliminary study revealed that the CS-TOS was a potential micellar carrier for PTX. In this study, some further researches were done using Taxol formulation as the control to evaluate the micelle system deeply. In vitro cell experiments demonstrated that the cytotoxic effect of PTX-loaded CS-TOS micelles against MCF-7 cells was comparable with that of Taxol formulation, and the PTX-loaded micelles had excellent cellular uptake ability, which was in a time-dependent manner. The in vivo pharmacokinetic study in rats showed that the micelles prolonged the half-life and increased AUC of PTX than Taxol formulation. From biodistribution study, it was clear that for micelles, the drug concentrations in the liver and spleen were significantly higher than those of Taxol formulation, but much lower in the heart and kidney. Furthermore, the PTX-loaded micelles showed superior antitumor effect, but yielded less toxicity as indicated by the results of antitumor efficacy study and survival study in U14 tumor-bearing mice. These results suggested that CS-TOS micelles could be a potentially useful drug delivery system to improve the performance and safety of PTX.

New trends in guided nanotherapies for digestive cancers: A systematic review

Digestive tract tumors are among the most common and deadliest malignancies worldwide, mainly due to late diagnosis and lack of efficient therapeutics. Current treatments essentially rely on surgery associated with (neo)adjuvant chemotherapy agents. Despite an upfront response, conventional drugs often fail to eliminate highly aggressive clones endowed with chemoresistant properties, which are responsible for tumor recurrence and disease dissemination. Synthetic drugs also present severe adverse systemic effects, hampering the administration of biologically effective dosages. Nanoencapsulation of chemotherapeutic agents within biocompatible polymeric or lipid matrices holds great potential to improve the pharmacokinetics and efficacy of conventional chemotherapy while reducing systemic toxicity. Tagging nanoparticle surfaces with specific ligands for cancer cells, namely monoclonal antibodies or antibody fragments, has provided means to target more aggressive clones, further improving the selectivity and efficacy of nanodelivery vehicles. In fact, over the past twenty years, significant research has translated into a wide array of guided nanoparticles, providing the molecular background for a new generation of intelligent and more effective anti-cancer agents. Attempting to bring awareness among the medical community to emerging targeted nanopharmaceuticals and foster advances in the field, we have conducted a systematic review about this matter. Emphasis was set on ongoing preclinical and clinical trials for liver, colorectal, gastric and pancreatic cancers. To the best of our knowledge this is the first systematic and integrated overview on this field. Using a specific query, 433 abstracts were gathered and narrowed to 47 manuscripts when matched against inclusion/exclusion criteria. All studies showed that active targeting improves the effectiveness of the nanodrugs alone, while lowering its side effects. The main focus has been on hepatocarcinomas, mainly by exploring glycans as homing molecules. Other ligands such as peptides/small proteins and antibodies/antibody fragments, with affinity to either tumor vasculature or tumor cells, have also been widely and successfully applied to guide nanodrugs to gastrointestinal carcinomas. Conversely, few solutions have been presented for pancreatic tumors. To this date only three nanocomplexes have progressed beyond pre-clinical stages: i) PK2, a galactosamine-functionalized polymeric-DOX formulation for hepatocarcinomas; ii) MCC-465, an anti-(myosin heavy chain a) immunoliposome for advanced stage metastatic solid tumors; and iii) MBP-426, a transferrin-liposome-oxaliplatin conjugate, also for advanced stage tumors. Still, none has been approved for clinical use. However, based on the high amount of pre-clinical studies showing enthusiastic results, the number of clinical trials is expected to increase in the near future. A more profound understanding about the molecular nature of chemoresistant clones and cancer stem cell biology will also contribute to boost the field of guided nanopharmacology towards more effective solutions.

Specific targeting of A54 homing peptide-functionalized dextran-g-poly(lactic-co-glycolic acid) micelles to tumor cells

The delivery of chemotherapeutics into tumor cells is a fundamental knot for tumor-target therapy to improve the curative effect and avoid side effects. Here, A54 peptide-functionalized poly(lactic-co-glycolic acid)-grafted dextran (A54-Dex-PLGA) was synthesized. The synthesized A54-Dex-PLGA self-assembled to form micelles with a low critical micelle concentration of 16.79 μg·mL⁻¹ and diameter of about 50 nm. With doxorubicin (DOX) base as a model antitumor drug, the drug-encapsulation efficiency of DOX-loaded A54-Dex-PLGA micelles (A54-Dex-PLGA/DOX) reached up to 75%. In vitro DOX release from the A54-Dex-PLGA/DOX was prolonged to 72 hours. The A54-Dex-PLGA micelles presented excellent internalization ability into hepatoma cells (BEL-7402 cell line and HepG2 cell line) in vitro, and the cellular uptake of the micelles by the BEL-7402 cell line was specific, which was demonstrated by the blocking experiment. In vitro antitumor activity studies confirmed that A54-Dex-PLGA/DOX micelles suppressed tumor-cell (BEL-7402 cell) growth more effectively than Dex-PLGA micelles. Furthermore, in vivo biodistribution testing demonstrated that the A54-Dex-PLGA micelles had a higher distribution ability to BEL-7402 tumors than that to HepG2 tumors.

Diagnostic imaging and therapeutic application of nanoparticles targeting the liver

Liver diseases, particularly viral hepatitis, cirrhosis and hepatocellular carcinoma, are common in clinical practice with high morbidity and mortality worldwide. Many substances for diagnostic imaging and therapy of liver diseases may have either severe adverse effects or insufficient effectiveness in vivo because of their nonspecific uptake. Therefore, by targeting the delivery of drugs into the liver or specific liver cells, drug efficiency may be largely improved. This review summarizes the up-to-date research progress focusing on nanoparticles targeting the liver for both diagnostic and therapeutic purposes. Targeting strategies, mechanisms of enhanced effects, and clinical applications of nanoparticles are discussed specifically. We believe that new targeting nanotechnology such as nanoprobes for multi-modality imaging and multifunctional nanoparticles would facilitate significant advancements in this active research area in the near future.

Chitosan oligosaccharide copolymer micelles with double disulphide linkage in the backbone associated by H-bonding duplexes for targeted intracellular drug delivery

Folic acid conjugated block copolymer micelles with H-bonding associated double disulphide linkage in the backbone were developed.

TNYL peptide functional chitosan-g-stearate conjugate micelles for tumor specific targeting

Nowadays, a real challenge in cancer therapy is to design drug delivery systems that can achieve high concentrations of drugs at the target site for improved therapeutic effect with reduced side effects. In this research, we designed and synthesized a homing peptide-(TNYLFSPNGPIA, TNYL) modified chitosan-g-stearate (CS) polymer micelle (named T-CS) for targeting delivery. The peptide displayed specific binding affinity to EphB4 which is a member of the Eph family of receptor tyrosine protein kinases. The amphiphilic polymer T-CS can gather into micelles by themselves in an aqueous environment with a low critical micelle concentration value (91.2 μg/L) and nano-scaled size (82.1±2.8 nm). The drug encapsulation efficiency reached 86.43% after loading the hydrophobic drug doxorubicin (DOX). The cytotoxicity of T-CS/DOX against SKOV3 cells was enhanced by approximately 2.3-fold when compared with CS/DOX. The quantitative and qualitative analysis for cellular uptake indicated that TNYL modification can markedly increase cellular internalization in the EphB4-overexpressing SKOV3 cell line, especially with a short incubation time. It is interesting that relatively higher uptake of the T-CS/DOX micelles by SKOV3 cells (positive-EphB4) than A549 cells (negative-EphB4) was observed when the two cells were co-incubated. Furthermore, in vivo distribution experiment using a bilateral-tumor model showed that there was more fluorescence accumulation in the SKOV3 tumor than in the A549 tumor over the whole experiment. These results suggest that TNYL-modified CS micelles may be promising drug carriers as targeting therapy for the EphB4-overexpressing tumor.

Intracellular pH-sensitive delivery CaCO3 nanoparticles templated by hydrophobic modified starch micelles

CaCO₃ nanoparticles were prepared using starch–octanoic acid chemical conjugate micelle solution as a template to improve the acid pH sensitive release profile.

Polysaccharide-based micelles for drug delivery

Delivery of hydrophobic molecules and proteins has been an issue due to poor bioavailability following administration. Thus, micelle carrier systems are being investigated to improve drug solubility and stability. Due to problems with toxicity and immunogenicity, natural polysaccharides are being explored as substitutes for synthetic polymers in the development of new micelle systems. By grafting hydrophobic moieties to the polysaccharide backbone, self-assembled micelles can be readily formed in aqueous solution. Many polysaccharides also possess inherent bioactivity that can facilitate mucoadhesion, enhanced targeting of specific tissues, and a reduction in the inflammatory response. Furthermore, the hydrophilic nature of some polysaccharides can be exploited to enhance circulatory stability. This review will highlight the advantages of polysaccharide use in the development of drug delivery systems and will provide an overview of the polysaccharide-based micelles that have been developed to date.