EGFR-targeted multifunctional polymersomal doxorubicin induces selective and potent suppression of orthotopic human liver cancer in vivo

Use of a Cyclic α-Alkylidene-β-Diketone as a Cleavable Linker Strategy for Antibody-Drug Conjugates

In the fast-evolving landscape of targeted cancer therapies, the revolutionary class of biotherapeutics known as antibody-drug conjugates (ADCs) are taking center stage. Most clinically approved ADCs utilize cleavable linkers to temporarily attach potent cytotoxic payloads to antibodies, allowing selective payload release under tumor-specific conditions. In this study, we explored the utilization of 1-(4,4-dimethyl-2,6-dioxocyclohexylidene)ethyl (Dde), a cyclic β-diketone featuring an active alkylidene group, to develop a novel chemically labile linker. This linker was designed to exploit the difference in reduction potential between the intracellular compartment and plasma. Upon reduction of an azido trigger strategically installed neighboring the cyclic β-diketone, the resulting nucleophilic primary amine reacts with the alkylidene group facilitated by a favorable ring closure reaction in accordance with Baldwin's rules. Consequently, this reaction enables the simultaneous release of the attached cytotoxic payload. The therapeutic utility of this novel linker strategy was demonstrated by separate conjugation of the linker to two epidermal growth factor receptor (EGFR)-targeting ligands to afford a peptide-drug conjugate and an ADC. This work comprises a significant contribution to the bioconjugation field by introducing the alkylidene cyclic β-diketone as a tunable scaffold used for the temporary conjugation of therapeutic agents to peptides and proteins.

Development of Cyclic Peptides Targeting the Epidermal Growth Factor Receptor in Mesenchymal Triple-Negative Breast Cancer Subtype

Triple-negative breast cancer (TNBC) is an aggressive malignancy characterized by the lack of expression of estrogen and progesterone receptors and amplification of human epidermal growth factor receptor 2 (HER2). Being the Epidermal Growth Factor Receptor (EGFR) highly expressed in mesenchymal TNBC and correlated with aggressive growth behavior, it represents an ideal target for anticancer drugs. Here, we have applied the phage display for selecting two highly specific peptide ligands for targeting the EGFR overexpressed in MDA-MB-231 cells, a human TNBC cell line. Molecular docking predicted the peptide-binding affinities and sites in the extracellular domain of EGFR. The binding of the FITC-conjugated peptides to human and murine TNBC cells was validated by flow cytometry. Confocal microscopy confirmed the peptide binding specificity to EGFR-positive MDA-MB-231 tumor xenograft tissues and their co-localization with the membrane EGFR. Further, the peptide stimulation did not affect the cell cycle of TNBC cells, which is of interest for their utility for tumor targeting. Our data indicate that these novel peptides are highly specific ligands for the EGFR overexpressed in TNBC cells, and thus they could be used in conjugation with nanoparticles for tumor-targeted delivery of anticancer drugs.

Peptide-functionalized therapeutic nanoplatform for treatment orthotopic triple negative breast cancer and bone metastasis

Epidermal Growth Factor Receptor (EGFR) is a promising therapeutic target for triple-negative breast cancer (TNBC). Recently, specific EGFR-targeting peptide GE11-based delivery nano-system shows excellent potential because of its chemical versatility and good targeting ability. However, no further research focusing on the downstream of EGFR after binding with GE11 was explored. Hence, we tailor-designed a self-assembled nanoplatform named GENP using amphiphilic molecule of stearic acid-modified GE11. After loading doxorubicin (DOX), the resulted nanoplatform GENP@DOX demonstrated high loading efficiency and sustainable drug release. Importantly, our findings proved that GENP alone significantly suppressed the proliferation of MDA-MB-231 cells via EGFR-downstream PI3K/AKT signaling pathways, contributing to the synergistic treatment with its DOX release. Further work illustrated remarkable therapeutic efficacy both in orthotopic TNBC and its bone metastasis models with minimal biotoxicity. Together, the results highlight that our GENP-functionalized nanoplatform is a promising strategy for the synergistic therapeutic efficacy targeting EGFR-overexpressed cancer.

Signature construction and molecular subtype identification based on cuproptosis-related genes to predict the prognosis and immune activity of patients with hepatocellular carcinoma

Background

Hepatocellular carcinoma (HCC) is one of the most common malignancies in the world, with high incidence, high malignancy, and low survival rate. Cuproptosis is a novel form of cell death mediated by lipoylated TCA cycle proteins-mediated novel cell death pathway and is highly associated with mitochondrial metabolism. However, the relationship between the expression level of cuproptosis-related genes (CRGs) and the prognosis of HCC is still unclear.

Methods

Combining the HCC transcriptomic data from The Cancer Genome Atlas(TCGA) and Gene Expression Omnibus (GEO) databases, we identified the differentially expressed cuproptosis-related genes (DECRGs) and obtained the prognosis-related DECRGs through univariate regression analysis.LASSO and multivariate COX regression analyses of these DECRGs yielded four genes that were used to construct the signature. Next, we use ROC curves to evaluate the performance of signatures. The tumor microenvironment, immune infiltration, tumor mutation load, half-maximum suppression concentration, and immunotherapy effects were also compared between the low-risk and high-risk groups. Finally, we analyzed the expression level, prognosis, and immune infiltration correlation on the four genes that constructed the model.

Results

Four DECRGs s were used to construct the signature. The ROC curves indicated that signature can better assess the prognosis of HCC patients. Patients were grouped according to the signature risk score. Patients in the low-risk group had a significantly longer survival time than those in the high-risk group. Furthermore, the tumor mutation burden (TMB) values were associated with the risk score and the higher-risk group had a higher proportion of TP53 mutations than the low-risk group.ESTIMATE analysis showed significant differences in stromal scores between the two groups.N6-methyladenosine (m6A) and multiple immune checkpoints were expressed at higher levels in the high-risk group. Then, we found that signature score correlated with chemotherapeutic drug sensitivity and immunotherapy efficacy in HCC patients. Finally, we further confirmed that the four DECRGs genes were associated with the prognosis of HCC through external validation.

Conclusions

We studied from the cuproptosis perspective and developed a new prognostic feature to predict the prognosis of HCC patients. This signature with good performance will help physicians to evaluate the overall prognosis of patients and may provide new ideas for clinical decision-making and treatment strategies.

Polymersome-stabilized doxorubicin-lipiodol emulsions for high-efficacy chemoembolization therapy

Transarterial chemoembolization (TACE) with free doxorubicin-lipiodol emulsions (free DOX/L) is a favored clinical treatment for advanced hepatocellular carcinoma (HCC) patients ineligible for radical therapies; however, its inferior colloidal stability not only greatly reduces its tumor retention but also hastens drug release into blood circulation, leading to suboptimal clinical outcomes. Here, we find that disulfide-crosslinked polymersomes carrying doxorubicin (Ps-DOX) form super-stable and homogenous water-in-oil microemulsions with lipiodol (Ps-DOX/L). Ps-DOX/L microemulsions had tunable sizes ranging from 14 to 44 μm depending on the amount of Ps-DOX, were stable over 2 months storage as well as centrifugation, and exhibited nearly zero-order DOX release within 15 days. Of note, Ps-DOX induced 2.3-13.4 fold better inhibitory activity in all tested rat, murine and human liver tumor cells than free DOX likely due to its efficient redox-triggered intracellular drug release. Interestingly, transarterial administration of Ps-DOX/L microemulsions in orthotopic rat N1S1 syngeneic HCC model showed minimal systemic DOX exposure, high and long hepatic DOX retention, complete tumor elimination, effective inhibition of angiogenesis, and depleted adverse effects, significantly outperforming clinically used free DOX/L emulsions. This smart polymersome stabilization of doxorubicin-lipiodol microemulsions provides a novel TACE strategy for advanced tumors.

Challenges for the application of EGFR-targeting peptide GE11 in tumor diagnosis and treatment

Abnormal regulation of cell signaling pathways on cell survival, proliferation and migration contributes to the development of malignant tumors. Among them, epidermal growth factor receptor (EGFR) is one of the most important biomarkers in many types of malignant solid tumors. Its over-expression and mutation status can be served as a biomarker to identify patients who can be benifit from EGFR tyrosine kinase inhibitors and anti-EGFR monocloncal antibody (mAb) therapy. For decades, researches on EGFR targeted ligands were actively carried out to identify potent candidates for cancer therapy. An ideal EGFR ligand can competitively inhibit the binding of endogenous growth factor, such as epidermal growth factor (EGF) and transforming growth factor-α(TGF-α) to EGFR, thus block EGFR signaling pathway and downregulate EGFR expression. Alternatively, conjugation of EGFR ligands on drug delivery systems (DDS) can facilitate targeting delivery of therapeutics or diagnostic agents to EGFR over-expression tumors via EGFR-mediated endocytosis. GE11 peptide is one of the potent EGFR ligand screened from a phage display peptide library. It is a dodecapeptide that can specifically binds to EGFR with high affinity and selectivity. GE11 has been widely used in the diagnosis and targeted delivery of drugs for radiotherapy, genetherapy and chemotherpy against EGFR positive tumors. In this review, the critical factors affecting the in vivo and in vitro targeting performance of GE11 peptide, including ligand-receptor intermolecular force, linker bond properties and physiochemical properties of carrier materials, are detailedly interpreted. This review provides a valuable vision for the rational design and optimization of GE11-based active targeting strategies for cancer treatment, and it will promote the translation studies of GE11 from lab research to clinical application.

Polymeric nanocarriers: A promising tool for early diagnosis and efficient treatment of colorectal cancer

BACKGROUND

Colorectal cancer (CRC) is the third most prevalent type of cancer for incidence and second for mortality worldwide. Late diagnosis and inconvenient and expensive current diagnostic tools largely contribute to the progress of the disease. The use of chemotherapy in the management of CRC significantly reduces tumor growth, metastasis, and morbidity rates. However, poor solubility, low cellular uptake, nonspecific distribution, multiple drug resistance and unwanted adverse effects are still among the major drawbacks of chemotherapy that limit its clinical significance in the treatment of CRC. Owing to their remarkable advantages over conventional therapies, the use of nanotechnology-based delivery systems especially polymeric nanocarriers (PNCs) has revolutionized many fields including disease diagnosis and drug delivery.

AIM OF REVIEW

In this review, we shed the light on the current status of using PNCs in the diagnosis and treatment of CRC with a special focus on targeting strategies, surface modifications and safety concerns for different types of PNCs in colonic cancer delivery.

KEY SCIENTIFIC CONCEPTS OF REVIEW

The review explores the current progress on the use of PNCs in the diagnosis and treatment of CRC with a special focus on the role of PNCs in improvement of cellular uptake, drug targeting and co-delivery of chemotherapeutic agents. Possible toxicity and biocompatibility issues related to the use of PNCs and imitations and future recommendation for the use of those smart carriers in the diagnosis and treatment of CRC are also discussed.

Circumsporozoite Protein of Plasmodium berghei- and George Baker Virus A-Derived Peptides Trigger Efficient Cell Internalization of Bioconjugates and Functionalized Poly(ethylene glycol)-b-poly(benzyl malate)-Based Nanoparticles in Human Hepatoma Cells

In order to identify the peptides, selected from the literature, that exhibit the strongest tropism towards human hepatoma cells, cell uptake assays were performed using biotinylated synthetic peptides bound to fluorescent streptavidin or engrafted onto nanoparticles (NPs), prepared from biotin-poly(ethylene glycol)-block-poly(benzyl malate) (Biot-PEG-b-PMLABe) via streptavidin bridging. Two peptides, derived from the circumsporozoite protein of Plasmodium berghei- (CPB) and George Baker (GB) Virus A (GBVA10-9), strongly enhanced the endocytosis of both streptavidin conjugates and NPs in hepatoma cells, compared to primary human hepatocytes and non-hepatic cells. Unexpectedly, the uptake of CPB- and GBVA10-9 functionalized PEG-b-PMLABe-based NPs by hepatoma cells involved, at least in part, the peptide binding to apolipoproteins, which would promote NP’s interactions with cell membrane receptors of HDL particles. In addition, CPB and GBVA10-9 peptide–streptavidin conjugates favored the uptake by hepatoma cells over that of the human macrophages, known to strongly internalize nanoparticles by phagocytosis. These two peptides are promising candidate ligands for targeting hepatocellular carcinomas.

Enhancing the efficacy of albendazole for liver cancer treatment using mesoporous silica nanoparticles: an in vitro study

The present study aimed to synthesize albendazole (ABZ)-loaded Mobil Composition of Matter No. 41 (MCM-41 NPs) to increase the efficacy of the drug against liver cancer. ABZ was loaded into MCM-41 NPs, and after in vitro characterization, such as size, size distribution, zeta potential, morphology, chemical composition, thermal profile, drug release, surface and pore volume, and pore size, their biological effects were evaluated using 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide (MTT) cell migration assays. The results demonstrated that monodispersed and spherical NPs with a size of 220 ± 11.5 and 293 ± 8.7 nm, for MCM-41 NPs and ABZ-loaded MCM-41 NPs, respectively, and drug loading efficiency of 30 % were synthesized. ABZ was loaded physically into MCM-41 NPs, leading to a decrease in surface volume, pore size, and pore volume. Also, MCM-41 NPs could increase the cytotoxicity effects of ABZ by 2.9-fold (IC₅₀ = 23 and 7.9 µM for ABZ and ABZ-loaded MCM-41 NPs, respectively). In addition, both ABZ and ABZ-loaded MCM-41 NPs could restrain the cell migration by 12 %. Overall, the results of the present study suggest evaluating the potency of MCM-41 NPs, as a potent nanoplatform, for ABZ delivery in vivo environment.

See also the Graphical Abstract(Fig. 1).

Advances in Nanoliposomes for the Diagnosis and Treatment of Liver Cancer

The mortality rate of liver cancer is gradually increasing worldwide due to the increasing risk factors such as fatty liver, diabetes, and alcoholic cirrhosis. The diagnostic methods of liver cancer include ultrasound (US), computed tomography (CT), and magnetic resonance imaging (MRI), among others. The treatment of liver cancer includes surgical resection, transplantation, ablation, and chemoembolization; however, treatment still faces multiple challenges due to its insidious development, high rate of recurrence after surgical resection, and high failure rate of transplantation. The emergence of liposomes has provided new insights into the treatment of liver cancer. Due to their excellent carrier properties and maneuverability, liposomes can be used to perform a variety of functions such as aiding in imaging diagnoses, combinatorial therapies, and integrating disease diagnosis and treatment. In this paper, we further discuss such advantages.

Cetuximab-Polymersome-Mertansine Nanodrug for Potent and Targeted Therapy of EGFR-Positive Cancers

Targeted nanomedicines particularly armed with monoclonal antibodies are considered to be the most promising advanced chemotherapy for malignant cancers; however, their development is hindered by their instability and drug leakage problems. Herein, we constructed a robust cetuximab-polymersome-mertansine nanodrug (C-P-DM1) for highly potent and targeted therapy of epidermal growth factor receptor (EGFR)-positive solid tumors. C-P-DM1 with a tailored cetuximab surface density of 2 per P-DM1 exhibited a size of ca. 60 nm, high stability with minimum DM1 leakage, glutathione-triggered release of native DM1, and 6.0-11.3-fold stronger cytotoxicity in EGFR-positive human breast (MDA-MB-231), lung (A549), and liver (SMMC-7721) cancer cells (IC₅₀ = 27.1-135.5 nM) than P-DM1 control. Notably, intravenous injection of C-P-DM1 effectively repressed subcutaneous MDA-MB-231 breast cancer and orthotopic A549-Luc lung carcinoma in mice without inducing toxic effects. Strikingly, intratumoral injection of C-P-DM1 completely cured 60% of mice bearing breast tumor without recurrence. This robust cetuximab-polymersome-mertansine nanodrug provides a promising new strategy for targeted treatment of EGFR-positive solid malignancies.

EGFR-targeted pemetrexed therapy of malignant pleural mesothelioma

Malignant pleural mesothelioma (MPM) is a rare malignancy with poor prognosis, for which chemotherapy with pemetrexed (PEM) is among the few clinical treatments. PEM suffers, however, fast clearance, moderate drug exposure, and dose-limiting toxicities. Here, we report on epidermal growth factor receptor (EGFR)-targeted disulfide-crosslinked biodegradable chimaeric polymersomes (EGFR-CPs) to firmly load PEM and boost chemotherapy of MPM. EGFR-CPs encapsulating 8.7-16.4 wt.% PEM (EGFR-CPs-PEM) showed diameters of 62-65 nm and reduction-responsive drug release property. EGFR-CPs-PEM was more efficiently taken up by EGFR-overexpressed MSTO-211H cells, inducing about 4.7-fold enhanced anticancer activity compared with non-targeted CPs-PEM control. Intriguingly, the in vivo experiments in MSTO-211H xenograft mouse model revealed that EGFR-CPs-PEM brought about superior tumor deposition and penetration to CPs-PEM, and significantly more potent tumor repression than CPs-PEM and free PEM. This polymersome-enabled EGFR-targeted delivery of PEM offers an appealing therapeutic strategy for MPM.

Recent advances in bionanomaterials for liver cancer diagnosis and treatment

According to the World Health Organization, liver cancer is the fourth leading cause of cancer associated with death worldwide. It demands effective treatment and diagnostic strategies to hinder its recurrence, complexities, aggressive metastasis and late diagnosis. With recent progress in nanotechnology, several nanoparticle-based diagnostic and therapeutic modalities have entered into clinical trials. With further developments in nanoparticle mediated liver cancer diagnosis and treatment, the approach holds promise for improved clinical liver cancer management. In this review, we discuss the key advances in nanoparticles that have potential for liver cancer diagnosis and treatment. We also discuss the potential of nanoparticles to overcome the limitations of existing therapeutic modalities.

Doxorubicin Delivered via ApoE-Directed Reduction-Sensitive Polymersomes Potently Inhibit Orthotopic Human Glioblastoma Xenografts in Nude Mice

Purpose

Glioblastoma multiforme (GBM) poorly responds to chemotherapy owing to the existence of blood-brain barriers (BBB). It has been a long desire to develop BBB-permeable vehicles to facilitate drug targeting to GBM.

Method and Results

Here, we report that doxorubicin hydrochloride loaded in ApoE peptide-functionalized reduction-sensitive polymersomes (ApoE-PS-DOX) induces potent therapy of orthotopic U-87 MG model in nude mice. ApoE-PS-DOX with varying amount of ApoE (10~30 mol%) all had stable DOX loading and small sizes (< 90 nm). As revealed by flow cytometry, confocal microscopy, apoptosis and MTT assays, ApoE-PS-DOX with 20 mol.% ApoE induced the best cellular uptake and inhibitory effect to U-87 MG cells, which were much better than the non-targeted PS-DOX and liposomal doxorubicin (Lipo-DOX) used in the clinic. ApoE-PS-DOX revealed a pharmacokinetic profile comparable to PS-DOX but induced considerably better growth inhibition of orthotopically xenografted U-87 MG tumors in nude mice than PS-DOX and Lipo-DOX, leading to significant survival benefits with a median survival time of 44 days, which was almost doubled relative to the phosphate-buffered saline (PBS) group. Moreover, in contrast to mice treated with Lipo-DOX and PS-DOX, ApoE-PS-DOX group exhibited little body weight loss, signifying that ApoE-PS-DOX not only has low side effects but also can effectively inhibit glioblastoma invasion.

Conclusion

This ApoE-docked multifunctional polymersomal doxorubicin induces potent and safe chemotherapy of orthotopic U-87 MG model in nude mice offering an alternative treatment modality for GBM.

Facile fabrication of robust, hyaluronic acid-surfaced and disulfide-crosslinked PLGA nanoparticles for tumor-targeted and reduction-triggered release of docetaxel

It is highly tempting to develop high-efficacy targeted nanotherapeutics based on FDA approved polymers like PLGA. Herein, we describe facile fabrication of robust, hyaluronic acid-surfaced and disulfide-crosslinked star-PLGA nanoparticles (HA-sPLGA XNPs) for targeted and reduction-triggered release of docetaxel (DTX), achieving markedly enhanced treatment of A549 lung tumor in vivo. HA-sPLGA XNPs carrying 5.2 wt.% DTX (DTX-HA-sPLGA XNPs) had a size of 105.5 ± 0.5 nm and great stability while almost completely released DTX under 10 mM glutathione. Confocal and flow cytometry experiments revealed fast cellular uptake of HA-sPLGA XNPs by CD44-overexpressing A549 cells. DTX-HA-sPLGA XNPs held much higher potency to A549 cells than DTX-loaded HA-surfaced and non-crosslinked star-PLGA nanoparticles (DTX-HA-sPLGA NPs), DTX-loaded HA-surfaced and non-crosslinked linear-PLGA nanoparticles (DTX-HA-lPLGA NPs), and free DTX (IC₅₀ = 0.18 versus 0.38, 1.21 and 0.83 µg DTX equiv./mL). Intriguingly, DTX-HA-sPLGA XNPs revealed a prolonged elimination half-life of 4.18 h and notable accretion of 9.49%ID/g in A549 tumor after 8 h injection. Accordingly, DTX-HA-sPLGA XNPs demonstrated significantly better suppression of subcutaneous A549 lung tumor than DTX-HA-PLGA NPs, DTX-HA-lPLGA NPs, and free DTX controls. HA-sPLGA XNPs with low toxicity and multi-functionality appear to be a unique targeted vehicle for chemotherapy of CD44-overexpressing tumors. STATEMENT OF SIGNIFICANCE: PLGA nanoparticles with superior safety and biodegradability are among the most advanced vehicles for therapeutic delivery. The efficacy of nanomedicines based on PLGA is, however, suboptimal, due to poor tumor cell selectivity and uptake, drug leakage, and slow drug release at the pathological site. It is highly desired to develop functional PLGA nanoparticles to improve their tumor-targeting ability and therapeutic efficacy. The sophisticated fabrication and potential toxicity concerns of reported novel PLGA nanoformulations, nevertheless, preclude their clinical translation. Here, we developed hyaluronic acid-surfaced and disulfide-crosslinked star-PLGA nanoparticles (HA-sPLGA XNPs) that enabled stable encapsulation and targeted delivery of docetaxel (DTX) to CD44+ A549 lung cancer cells in vitro and in vivo, affording markedly improved tumor accumulation and repression and lower side effects compared with free DTX control. Importantly, HA-sPLGA XNPs are based on fully biocompatible materials and comparably simple to fabricate. The evident tumor targetability and safety makes HA-sPLGA XNPs a unique and potentially translatable platform for chemotherapy of CD44+ cancers.

Peptide-Based Strategies for Targeted Tumor Treatment and Imaging

Cancer is one of the leading causes of death worldwide. The development of cancer-specific diagnostic agents and anticancer toxins would improve patient survival. The current and standard types of medical care for cancer patients, including surgery, radiotherapy, and chemotherapy, are not able to treat all cancers. A new treatment strategy utilizing tumor targeting peptides to selectively deliver drugs or applicable active agents to solid tumors is becoming a promising approach. In this review, we discuss the different tumor-homing peptides discovered through combinatorial library screening, as well as native active peptides. The different structure–function relationship data that have been used to improve the peptide’s activity and conjugation strategies are highlighted.

Ligand decorated biodegradable nanomedicine in the treatment of cancer

Cancer is one of the major global health problems, responsible for the second-highest number of deaths. The genetic and epigenetic changes in the oncogenes or tumor suppressor genes alter the regulatory pathways leading to its onset and progression. Conventional methods are used in appropriate combinations for the treatment. Surgery effectively treats localized tumors; however, it fails to treat metastatic tumors, leading to a spread in other organs, causing a high recurrence rate and death. Among the different strategies, the nanocarriers-based approach is highly sought for, but its nonspecific delivery can cause a profound side effect on healthy cells. Targeted nanomedicine has the advantage of targeting cancer cells specifically by interacting with the receptors overexpressed on their surface, overcoming its non-specificity to target healthy cells. Nanocarriers prepared from biodegradable and biocompatible materials are decorated with different ligands by encapsulating therapeutic or diagnostic agents or both to target cancer cells overexpressing the receptors. Scientists are now utilizing a theranostic approach to simultaneously evaluate nanocarrier bio-distribution and its effect on the treatment regime. Herein, we have summarized the recent 5-year efforts in the development of the ligands decorated biodegradable nanocarriers, as a targeted nanomedicine approach, which has been highly promising in the treatment of cancer.

A robust optimization approach for the breast cancer targeted design of PEtOx-b-PLA polymersomes

The equipping of nanoparticles with the peptide moiety recognizing a particular receptor, enables cell or tissue-specific targeting, therefore the optimization of the targeted nanoparticles is a key factor in the formulation design process. In this paper, we report the optimization concept of Doxorubicin encapsulating PEtOx-b-PLA polymersome formulation equipped with Peptide18, which is a breast cancer recognizing tumor homing peptide, and the unveiling of the cell-specific delivery potential. The most dominant formulation parameters, which are the polymer to Doxorubicin mass ratio (w/w) and the aqueous to organic phase ratio (v/v), were optimized using Central Composite Design (CCD) based Response Surface Methodology. The characteristics of optimum polymersome formulation were determined as the hydrodynamic diameter of 146.35 nm, the PDI value of 0.136, and the encapsulation efficiency of 57.11% and TEM imaging, which are in agreement with the DLS data, showed the spherical morphology of the polymersomes. In order to demonstrate the breast cancer-specific delivery of targeted polymersomes, the flow cytometry and confocal microscopy analyses were carried out. The targeted polymersomes were accumulated 8 times higher in AU565 cells compared to MCF10A cells and the intracellular Doxorubicin was almost 10 times higher in AU565 cells. The CCD-mediated optimized targeted polymersomes proposed in this report holds the promise of targeted therapy for breast cancer and can be potentially used for the development of novel treatments.

Alleviation of the doxorubicin-induced nephrotoxicity by fasudil in vivo and in vitro

OBJECTIVE

Treatment with the chemotherapeutic agent, doxorubicin (DOX), is limited by side effects. We have previously demonstrated that fasudil, a Rho/ROCK inhibitor, has antioxidant, anti-inflammatory and anti-apoptotic effects in contrast-induced acute kidney injury model. The present study to investigated the possible protective effect of fasudil, on DOX-induced nephrotoxicity.

MATERIALS AND METHOD

In vivo: Forty male C57BL/6 male mice were randomly divided into 4 groups: Control group, DOX treatment group (DOX group), DOX + low dose fasudil (DOX + L group), DOX + high dose fasudil (DOX + H group). Mice in 2-4 groups received DOX (2.5 mg/kg, i.p.) once a week for 8 weeks. The 3 and 4 group were given 2 mg/kg/d or 10 mg/kg/d fasudil before DOX injection. respectively. Meanwhile, the control group received saline. At the end of week eight, blood samples were collected for biochemical testing. The kidneys were removed for histological, immunohistochemical, Western blot, quantitative real-time PCR (qRT-PCR), and molecular detection. In vitro: NRK-52E cells were treated with 40 uM fasudil for 12 h, then incubated with 1 uM DOX for 24 h. Cells then collected for qRT-PCR and Western blot.

RESULTS

In vivo, fasudil treatment ameliorated DOX-induced immunofluorescence reaction of DNA damage-related factors (8-OHdG), decreased the expression of Bax, Caspase-3, p16, p21 and p53, and increased the expression of protein of Bcl-2, Bmi-1 and Sirt-1. In the mouse model, administration of fasudil significantly ameliorated DOX-induced kidney damage, suppressed cell apoptosis and senescence, ameliorated redox imbalance and DNA damage. At the same time, DOX produced obvious kidney damage revealed by kidney functions changes: increased serum creatinine (SCr) and blood urea nitrogen (BUN) concentrations. In addition, kidney tissue staining in the DOX group showed abnormal structure and fibroproliferative disorders. And DOX could promote the oxidation and senescence of kidney cells, leading to increased expression of 8-OHdG and senescence and apoptosis-related factors. On the contrary, fasudil treatment can effectively inhibit redox imbalance and DNA damage caused by DOX, and inhibit cell senescence and apoptosis. Fasudil can inhibit excessive activation of Rho/ROCK signaling pathway, thereby improving kidney tissue fibrosis and recovery kidney function.

CONCLUSION

Fasudil has a protective effect on DOX-induced nephrotoxicity in mice and NRK-52E cells, which can inhibit oxidative stress and DNA damage, inhibit apoptosis, and delays cell senescence by inhibiting RhoA/Rho kinase (ROCK) signaling pathway.

SP94 peptide mediating highly specific and efficacious delivery of polymersomal doxorubicin hydrochloride to hepatocellular carcinoma in vivo

The effective treatment of hepatocellular carcinoma (HCC) requires development of novel drug formulations that selectively kill HCC cells while sparing healthy liver cells. Here, we designed and investigated HCC-specific peptide, SP94 (SFSIIHTPILPLGGC), decorated smart polymersomal doxorubicin hydrochloride (SP94-PS-DOX) for potent treatment of orthotopic human SMMC-7721 HCC xenografts. SP94-PS-DOX was fabricated by post ligand-modification, affording robust nano-formulations with a diameter of ∼ 76 nm and DOX content of 9.9 wt.%. The internalization of SP94-PS-DOX by SMMC-7721 cells showed a clear dependence on SP94 surface densities, in which 30 % SP94 resulted in ca. 3-fold better cellular uptake over non-targeted control (PS-DOX). In accordance, SP94-PS-DOX exhibited superior inhibition of SMMC-7721 cells to PS-DOX and clinical liposome injections (Lipo-DOX). Notably, a remarkable tumor deposition of 14.9 %ID/g and tumor-to-normal liver ratio of ca. 6.9 was observed for SP94-PS-DOX in subcutaneous SMMC-7721 HCC xenografts. More interestingly, SP94-PS-DOX under 10 mg DOX/kg induced far better therapeutic efficacy toward orthotopic SMMC-7721 HCC models than PS-DOX and Lipo-DOX controls giving substantial survival benefits and little adverse effects. The remarkable specificity and therapeutic outcomes lend SP94-PS-DOX promising for targeted HCC therapy.

Synthesis of a novel 99mTc labeled GE11 peptide for EGFR SPECT imaging

PURPOSE

This study investigated a novel SPECT agent for the noninvasive imaging of EGFR-overexpressing tumors.

METHODS

The EGFR-targeting peptide GE11 was synthesized with the introduction of four amino acids (GGGC) to its C-terminal to act as a strong chelator and radiolabeled using ^99mTc. The radiochemical yield of the ^99mTc-peptide-GE11 were evaluated using RP-HPLC. Cellular assays of the probe were performed on two NSCLC cell lines: A549 (high expression) and H23 (low expression). Biodistribution and SPECT imaging were performed in BALB/c nude mice bearing A549 and H23 NSCLC xenografts.

RESULTS

The ^99mTc-peptide-GE11 was prepared at high efficiency with radiochemical yield of 98.40 ± 1.00 % and it showed favorable stability. The cellular uptake was significantly higher in A549 than in H23 at all time points (especially at 1 h, which was 10.34 ± 0.72 and 2.04 ± 0.18, respectively). A nearly 56% reduction in probe uptake was observed after pretreatment with excess unlabeled peptides. The performance of SPECT imaging and biodistribution demonstrated higher uptake of the ^99mTc-peptide-GE11 in A549 xenograft than in H23 xenografts.

CONCLUSION

The new SPECT tracer ^99mTc-peptide-GE11 showed EGFR specificity, favorable pharmacokinetics and great potential for EGFR-targeted imaging.

GE11 peptide-installed chimaeric polymersomes tailor-made for high-efficiency EGFR-targeted protein therapy of orthotopic hepatocellular carcinoma

Hepatocellular carcinoma (HCC) remains a leading malignancy with a high mortality and little improvement in treatments. Protein drugs though known for their extraordinary potency and specificity have rarely been investigated for HCC therapy owing to lack of appropriate delivery systems. Here, we designed GE11 peptide-installed chimaeric polymersomes (GE11-CPs) for high-efficiency EGFR-targeted protein therapy of orthotopic SMMC-7721 HCC-bearing nude mice. GE11-CPs were assembled from poly(ethylene glycol)-b-poly(trimethylene carbonate-co-dithiolane trimethylene carbonate)-b-poly(aspartic acid) (PEG-P(TMC-DTC)-PAsp) and GE11-functionalized PEG-P(TMC-DTC), which allowed efficient loading and protection of proteins in the watery interior and fine-tuning of GE11 densities at the surface. CPs with short PAsp segments (degree of polymerization (DP) = 5, 10 and 15) exhibited a protein loading efficiency of 60%-72% and glutathione-responsive protein release. Saporin-loaded GE11-CPs had a size of 36 - 62 nm depending on GE11 densities and DP of PAsp. Notably, GE11-CPs with 10% GE11 revealed greatly enhanced uptake in SMMC-7721 cells, boosting the anticancer potency of saporin for over 3-folds compared with non-targeted control (half-maximal inhibitory concentration (IC₅₀) = 11.0 versus 36.3 nM). The biodistribution studies using Cy5-labeled cytochrome C as a model protein demonstrated about 3-fold higher accumulation of GE11-CPs formulation than CPs counterpart in both subcutaneous and orthotopic SMMC-7721 tumor models. Notably, saporin-loaded GE11-CPs revealed low toxicity, effective tumor inhibition and significant improvement of survival rate compared with PBS and non-targeted groups (median survival time: 99 versus 37 and 42 days). EGFR-targeted chimaeric polymersomes carrying proteins appear an interesting HCC treatment modality.

Increasing the antitumor efficacy of doxorubicin liposomes with coupling an anti-EGFR affibody in EGFR-expressing tumor models

Epidermal growth factor receptor (EGFR) is overexpressed in a wide range of solid tumors. In this study, we exploited a high-affinity EGFR-antagonistic affibody (Z_EGFR) coupled to a doxorubicin loaded pegylated liposome (LS-Dox) for concurrent passive and active targeting of EGFR⁺ A431 tumor cells in vitro and in vivo. The in vitro studies revealed that the Dox liposomes coupled with Z_EGFR (AS-Dox) showed a higher Dox uptake than LS-Dox in EGFR⁺ A431 cells but not in EGFR^- B16F10 cells, resulting in a selectively enhanced cytotoxicity. In vivo, AS-Dox confirmed its long circulation time and efficient accumulation in tumors. This targeted chemotherapy achieved greater tumor suppression. Further, this low-dose but effective targeted treatment reduced systemic toxicity such as body weight loss and organ injury demonstrated by H&E staining. Thus, selective targeting of LS-Dox coupled with Z_EGFR enhanced antitumor effects and improved systemic safety. These results demonstrated that LS-Dox coupled with Z_EGFR might be developed as a potential tool for therapy of EGFR⁺ tumors.

Dithiolane-Crosslinked Poly(ε-caprolactone)-Based Micelles: Impact of Monomer Sequence, Nature of Monomer, and Reducing Agent on the Dynamic Crosslinking Properties

Dithiolanes are used to obtain dynamic and reversible crosslinks between polymer chains. Copolymers of two different dithiolane-containing cyclic carbonate monomers and ε-caprolactone (CL) were synthesized by ring-opening polymerization using a methoxy-poly(ethylene glycol) (mPEG) initiator and different catalysts (diphenyl phosphate (DPP), methanesulfonic acid (MSA), 1,5,7-triazabicyclo[4.4.0]dec-5-ene (TBD), or Sn(Oct)2). Each catalyst required a different temperature, which had a pronounced influence on the reactivity ratio of the monomers and occurrence of transesterification reactions and, therefore, the monomer sequence. Self-crosslinkable copolymers were obtained when the dithiolane units were connected closely to the polymer backbone, whereas the presence of a linker unit between the dithiolane and the backbone prevented self-crosslinking. The former amphiphilic PEGylated block copolymers formed micelles by nanoprecipitation in the aqueous environment and crosslinked spontaneously by disulfide exchange during subsequent dialysis. These dithiolane-crosslinked micelles showed reduction-responsive dissociation in the presence of 10 mM glutathione, making them promising drug delivery systems for the intracellularly triggered cargo release.

Peptide-Drug Conjugates and Their Targets in Advanced Cancer Therapies

Cancer became recently the leading cause of death in industrialized countries. Even though standard treatments achieve significant effects in growth inhibition and tumor elimination, they cause severe side effects as most of the applied drugs exhibit only minor selectivity for the malignant tissue. Hence, specific addressing of tumor cells without affecting healthy tissue is currently a major desire in cancer therapy. Cell surface receptors, which bind peptides are frequently overexpressed on cancer cells and can therefore be considered as promising targets for selective tumor therapy. In this review, the benefits of peptides as tumor homing agents are presented and an overview of the most commonly addressed peptide receptors is given. A special focus was set on the bombesin receptor family and the neuropeptide Y receptor family. In the second part, the specific requirements of peptide-drug conjugates (PDC) and intelligent linker structures as an essential component of PDC are outlined. Furthermore, different drug cargos are presented including classical and recent toxic agents as well as radionuclides for diagnostic and therapeutic approaches. In the last part, boron neutron capture therapy as advanced targeted cancer therapy is introduced and past and recent developments are reviewed.

Emerging era of “somes”: polymersomes as versatile drug delivery carrier for cancer diagnostics and therapy

Over the past two decades, polymersomes have been widely investigated for the delivery of diagnostic and therapeutic agents in cancer therapy. Polymersomes are stable polymeric vesicles, which are prepared using amphiphilic block polymers of different molecular weights. The use of high molecular weight amphiphilic copolymers allows for possible manipulation of membrane characteristics, which in turn enhances the efficiency of drug delivery. Polymersomes are more stable in comparison with liposomes and show less toxicity in vivo. Furthermore, their ability to encapsulate both hydrophilic and hydrophobic drugs, significant biocompatibility, robustness, high colloidal stability, and simple methods for ligands conjugation make polymersomes a promising candidate for therapeutic drug delivery in cancer therapy. This review is focused on current development in the application of polymersomes for cancer therapy and diagnosis. Graphical abstract.

α3β1 Integrin-Targeting Polymersomal Docetaxel as an Advanced Nanotherapeutic for Nonsmall Cell Lung Cancer Treatment

Docetaxel (DTX) widely used for treating nonsmall cell lung cancer (NSCLC) patients is associated with dose-limiting side effects, especially neurotoxicity and myelosuppression. Here, we have developed cyclic cNGQGEQc peptide-directed polymersomal docetaxel (cNGQ-PS-DTX) as a targeted and multifunctional formulation for NSCLC. cNGQ-PS-DTX carrying 8.1 wt % DTX had a size of 93 nm, neutral surface charge, high stability, and glutathione-triggered DTX release behavior. Cytotoxicity studies demonstrated a clearly better antitumor activity of cNGQ-PS-DTX in α3β1 integrin overexpressing A549 human lung cancer cells than free DTX and nontargeted PS-DTX. cNGQ-PS-DTX showed a remarkably high tolerability (over 8 times better than free DTX) and slow elimination in mice. Importantly, cNGQ-PS-DTX exhibited greatly improved tumor accumulation and higher suppression of subcutaneous and orthotopic A549 xenografts as compared to PS-DTX and free DTX controls. α3β1 integrin-targeting polymersomal docetaxel emerges as an advanced nanotherapeutic for NSCLC treatment.

A glance over doxorubicin based-nanotherapeutics: From proof-of-concept studies to solutions in the market

Cancer is one of the leading causes of death worldwide and, as such, efforts are being done to find new chemotherapeutic drugs or, alternatively, novel approaches for the delivery of old ones. In this scope, when used as vehicles for drugs, nanomaterials may potentially maximize the efficacy of the treatment and reduce its side effects, for example by a change in drug's pharmacokinetics, cell targeting and/or specific stimuli-responsiveness. This is the case of doxorubicin (DOX) that presents a broad spectrum of activity and is one of the most widely used chemotherapeutic drugs as first-line treatment. Indeed, DOX is a very interesting example of a drug for which several nanosized delivery systems have been developed over the years. While it is true that some of these systems are already in the market, it is also true that research on this subject remains very active and that there is a continuing search for new solutions. In this sense, this review takes the example of doxorubicin, not so much with the focus on the drug itself, but rather as a case study around which very diverse and imaginative nanotechnology approaches have emerged.

Biomolecule–polymer hybrid compartments: combining the best of both worlds

Recent advances in bio/polymer hybrid compartments in the quest to obtain artificial cells, biosensors and catalytic compartments.

Dually Active Targeting Nanomedicines Based on a Direct Conjugate of Two Purely Natural Ligands for Potent Chemotherapy of Ovarian Tumors

Actively targeted nanomedicines have promised to revolutionize cancer treatment; however, their clinical translation has been limited by either low targetability, use of unsafe materials, or tedious fabrication. Here, we developed CD44 and folate receptor (FR) dually targeted nanoparticulate doxorubicin (HA/FA-NP-DOX) based on a direct conjugate of two purely natural ligands, hyaluronic acid and folic acid (FA), for safe, highly specific, and potent treatment of ovarian tumors in vivo. HA/FA-NP-DOX had a small size and high DOX loading, wherein the particle size decreased from 115, 93, to 89 nm with increasing degree of substitution of FA from 6.4, 8.5, to 11.1, while increased from 80, 93, to 103 nm with increasing DOX loading from 15.0, 23.1, to 31.4 wt %. Interestingly, HA/FA-NP-DOX exhibited excellent lyophilization redispersibility and long-term storage stability with negligible drug leakage while it released 91% of DOX in 48 h at pH 5.0. Cellular studies corroborated that HA/FA-NP-DOX possessed high selectivity to both CD44 and FR, resulting in strong killing of CD44- and FR-positive SKOV-3 ovarian cancer cells while low toxicity against CD44- and FR-negative L929 fibroblast cells. In vivo studies revealed a long elimination half-life of 5.6 h, an elevated tumor accumulation of 12.0% ID/g, and an effective inhibition of the SKOV-3 ovarian tumor for HA/FA-NP-DOX, leading to significant survival benefits over free DOX·HCl and phosphate-buffered saline controls. These dually targeted nanomedicines are simple and safe, providing a potentially translatable treatment for CD44- and FR-positive malignancies.

Roles of Thyroid Hormone-Associated microRNAs Affecting Oxidative Stress in Human Hepatocellular Carcinoma

Oxidative stress occurs as a result of imbalance between the generation of reactive oxygen species (ROS) and antioxidant genes in cells, causing damage to lipids, proteins, and DNA. Accumulating damage of cellular components can trigger various diseases, including metabolic syndrome and cancer. Over the past few years, the physiological significance of microRNAs (miRNA) in cancer has been a focus of comprehensive research. In view of the extensive level of miRNA interference in biological processes, the roles of miRNAs in oxidative stress and their relevance in physiological processes have recently become a subject of interest. In-depth research is underway to specifically address the direct or indirect relationships of oxidative stress-induced miRNAs in liver cancer and the potential involvement of the thyroid hormone in these processes. While studies on thyroid hormone in liver cancer are abundantly documented, no conclusive information on the potential relationships among thyroid hormone, specific miRNAs, and oxidative stress in liver cancer is available. In this review, we discuss the effects of thyroid hormone on oxidative stress-related miRNAs that potentially have a positive or negative impact on liver cancer. Additionally, supporting evidence from clinical and animal experiments is provided.

Low-toxicity transferrin-guided polymersomal doxorubicin for potent chemotherapy of orthotopic hepatocellular carcinoma in vivo

Hepatocellular carcinoma (HCC) remains one of the most lethal malignancies. The current chemotherapy with typically low tumor uptake and high toxicity reveals a poor anti-HCC efficacy. Here, we report transferrin-guided polycarbonate-based polymersomal doxorubicin (Tf-Ps-Dox) as a low-toxic and potent nanotherapeutic agent for effective treatment of liver tumor using a transferrin receptor (TfR)-positive human liver tumor SMMC-7721 model. Tf-Ps-Dox was facilely fabricated with small size of ca. 75 nm and varying Tf densities from 2.2% to 7.0%, by postmodification of maleimide-functionalized Ps-Dox (Dox loading content of 10.6 wt%) with thiolated transferrin. MTT assays showed that Tf-Ps-Dox had an optimal Tf surface density of 3.9%. The cellular uptake, intracellular Dox level, and anticancer efficacy of Tf-Ps-Dox to SMMC-7721 cells were inhibited by supplementing free transferrin, which supports that Tf-Ps-Dox is endocytosed through TfR. Interestingly, Tf-Ps-Dox exhibited a high accumulation of 8.5%ID/g (percent injected dose per gram of tissue) in subcutaneous SMMC-7721 tumors, which was 2- and 3-fold higher than that of nontargeted Ps-Dox and clinically used liposomal Dox formulation (Lipo-Dox), respectively. The median survival times of mice bearing orthotopic SMMC-7721 tumors increased from 82, 88 to 96 days when treated with Tf-Ps-Dox at Dox doses from 8, 12 to 16 mg/kg, which was significantly longer than that of Ps-Dox at 8 mg/kg (58 days) and Lipo-Dox at 4 mg/kg (48 days) or PBS (36 days). Notably, unlike Lipo-Dox, no body weight loss and damage to major organs could be discerned for all Tf-Ps-Dox groups, indicating that Tf-Ps-Dox caused low systemic toxicity. This transferrin-dressed polymersomal doxorubicin provides a potent and low-toxic treatment modality for human hepatocellular carcinoma. STATEMENT OF SIGNIFICANCE: Hepatocellular carcinoma (HCC) is one of the leading causes of cancer-related death worldwide. Vast work has focused on developing HCC-targeted nanotherapeutics. However, none of the nanotherapeutics has advanced to clinics, partly because the ligands used have not been validated in patients. Transferrin (Tf) is a natural ligand for transferrin receptor (TfR) that is overexpressed on cancerous cells, and it is currently under clinical trials (MBP-426 and CALAA-01) for the treatment of solid tumors. We designed Tf-functionalized polymersomal doxorubicin (Tf-Ps-Dox) for targeted therapy of orthotopic SMMC-7721 tumor in nude mice. Tf-Ps-Dox showed potent anti-HCC efficacy and significantly improved survival time with low toxicity as compared with nontargeted Ps-Dox and clinical liposomal Dox (Lipo-Dox). Hence, Tf-Ps-Dox is very appealing for targeted treatment of HCC.

Tailor-Made Semiconducting Polymers for Second Near-Infrared Photothermal Therapy of Orthotopic Liver Cancer

Liver tumor is one of the most lethal cancers due to its low ratio of surgical resection, high recurrence rate, and invasiveness. Photothermal therapy (PTT) possesses many advantages for cancer therapy because of its noninvasive nature. However, most PTT is conducted in the first near-infrared (NIR-I) window, so second near-infrared (NIR-II) photosensitizers with higher penetrating ability and clinical prospects are seriously desirable. Herein, a semiconducting polymer with optimized absorption in NIR-I and NIR-II regions is obtained by ternary copolymerization methodology. The prepared nanoparticle (NP) from the semiconducting polymer is used for treatment of orthotopic liver cancer upon laser irradiation. Compared with an 808 nm laser, a 1064 nm laser leads to more effective inhibition toward orthotopic liver cancer in the same conditions. These results thus demonstrate that the NIR-II polymeric NPs may inspire another aspect for highly efficient therapy of various orthotopic cancers.

Micro/nanomachines: what is needed for them to become a real force in cancer therapy?

Conventional drug delivery systems face several issues in medical applications, such as cyto/genotoxicity and off-targeting. These issues are particularly significant for cancer therapeutics because many of the currently used systems are toxic in their free form. Self-propelled autonomous micro/nanomachines offer promising alternative drug delivery systems based on high cargo loading, fast autonomous movement, precise targeting and the on-demand release of therapeutics in vivo. With this unique set of properties, it is not surprising that they are receiving considerable research attention. However, much less is reported about the drawbacks that hinder their systemic in vivo application. In this review, a biomedical perspective is used to assess micro/nanomotor-based anticancer drug delivery systems reported to date. Advantages along with present issues are highlighted and recommendations which need to be considered to develop an effective biocompatible micro/nanomotor-based delivery system for cancer therapy are discussed.

Near-infrared light-mediated and nitric oxide-supplied nanospheres for enhanced synergistic thermo-chemotherapy

Synergistic thermo-chemotherapy based multiple stimuli-responsive drug delivery systems have achieved significant improvement of cancer curative effects compared with single modality treatment. Nevertheless, the efficacy of thermo-chemotherapy is often reduced in drug-resistant tumors and the therapy method is unexpectedly associated with potential toxicity by utilizing poorly degradable materials. Here, we report a simple approach to encapsulate three drug payloads into multi-sensitive and degradable nanospheres (SDC@NS) to achieve anticancer effects. SDC@NS comprise a photothermal agent (cypate), an anticancer agent (doxorubicin), and a nitric oxide donor (SNAP) to achieve controllable drugs release in high concentration glutathione or under near-infrared light (NIR) irradiation. Hyperthermia from NIR-mediated cypate can accelerate cancer cell apoptosis in vitro and tumor tissue ablation in vivo. Furthermore, our results also confirmed that the nitric oxide-based SDC@NS showed significant cytotoxicity compared to the nitric oxide absent group (denoted as DC@NS) and an enhanced chemotherapy effect in vivo. The photothermal effect and payloads can synchronously realize cancer therapy and provide a new insight into the enhanced synergistic therapeutic effect.

Targeted chemotherapy for subcutaneous and orthotopic non-small cell lung tumors with cyclic RGD-functionalized and disulfide-crosslinked polymersomal doxorubicin

Lung cancer, with its high mortality and increasing morbidity, has become one of the most lethal malignancies worldwide. Here, we developed cyclic RGD peptide-directed and disulfide-crosslinked polymersomal doxorubicin (cRGD-PS-Dox) as a targeted chemotherapy for human non-small cell lung cancer (NSCLC). Notably, cRGD-PS-Dox exhibited a high Dox loading (15.2 wt.%), small hydrodynamic diameter (96 nm), superb stability, prominent targetability to α_vβ₃ integrin overexpressing A549 human lung cancer cells, and rapid release of the drug into nuclei, leading to a significantly improved antitumor activity compared with the control groups, i.e., PS-Dox and Lipo-Dox (a liposome injection employed in clinical settings). The pharmacokinetic and biodistribution results for cRGD-PS-Dox revealed similar elimination half-lives but two-fold enhanced tumor accumulation compared with PS-Dox and Lipo-Dox. Intriguingly, cRGD-PS-Dox effectively suppressed the growth of A549 lung tumors in both subcutaneous and orthotopic models with minimal adverse effects at a Dox dose of 12 mg/kg, leading to significant survival benefits compared with PS-Dox and Lipo-Dox. This α_vβ₃ integrin-targeting multifunctional polymersomal doxorubicin is highly promising for targeted chemotherapy of human NSCLC.

When wrapped in an engineered vesicle and augmented with cancer-targeting peptides, chemotherapy drug doxorubicin shows increased efficacy in a preclinical study. Zhiyuan Zhong, from China’s Soochow University, and his team developed the therapeutic (cRGD-PS-Dox) that targets cancer cells that overexpress a specific protein (α_vβ₃ integrin), such as those of non-small cell lung cancer. In vitro assays showed that cRGD-PS-Dox specifically targeted and inhibited cancer cells, and inhibited the growth and metastasis of human tumor grafts in mice. In vivo imaging confirmed a desirable drug stability profile and accumulation within tumors. These results showed clear advantages over non-targeted doxorubicin treatment controls. Mice treated with cRGD-PS-Dox also survived significantly longer than control-treated mice. The preferential attributes of the therapy make it a promising agent for further study into tumors that overexpress α_vβ₃ integrin.

Cascade Amplifiers of Intracellular Reactive Oxygen Species Based on Mitochondria-Targeted Core-Shell ZnO-TPP@D/H Nanorods for Breast Cancer Therapy

Tumor cells are vulnerable to reactive oxygen species (ROS). However, it is still a challenge to induce ROS efficiently in tumor cells. In this study, cascade amplifiers of intracellular ROS based on charge-reversible mitochondria-targeted ZnO-TPP@D/H nanorods (NRs) were first developed for breast cancer therapy. The core-shell ZnO-TPP@D/H NR with a particle size of 179.60 ± 5.67 nm was composed of a core of a ZnO NR, an inner shell of triphenyl phosphonium (TPP), and an outer shell of heparin. Doxorubicin (DOX) was loaded on ZnO-TPP@D/H NRs with high drug loading efficiency of 22.00 ± 0.18%. The zeta potential of ZnO-TPP@D/H NRs varied from 24.00 ± 0.83 to -34.06 ± 0.87 mV after heparin coating, protecting ZnO-TPP@D/H NRs from nonspecific adsorption in circulation. Mitochondrial targeting was achieved after the degradation of heparin. Cellular uptake assays showed that ZnO-TPP@D/H NRs could accumulate in mitochondria. ROS generation assays showed that ZnO-TPP@D/H NRs could triple the intracellular ROS in 4T1 cells (highly metastatic breast cancer cells) than free DOX. Western blot demonstrated that ZnO-TPP@D/H NRs dramatically induced cell apoptosis in 4T1 cells. In vivo experiments suggested the antitumor potential of ZnO-TPP@D/H NRs.

Functionalized selenium nanoparticles for targeted delivery of doxorubicin to improve non-small-cell lung cancer therapy

BACKGROUND

Selenium nanoparticles (SeNPs) loaded with chemotherapeutic drugs provided a novel perspective for cancer therapy.

MATERIALS AND METHODS

Here, SeNPs were modified with cyclic peptide (Arg-Gly-Asp-d-Phe-Cys [RGDfC]) to fabricate tumor-targeting delivery carrier RGDfC-SeNPs and, then, doxorubicin (DOX) was loaded to the surface of RGDfC-SeNPs for improving the antitumor efficacy of DOX in non-small-cell lung carcinoma therapy.

RESULTS

The chemical structure characterization of RGDfC-Se@DOX showed that DOX was successfully loaded to the surface of RGDfC-SeNPs to prepare functionalized antitumor drug delivery system RGDfC-Se@DOX. RGDfC-Se@DOX exhibited effective cellular uptake in A549 cells and entered A549 cells mainly by clathrin-mediated endocytosis pathway. Compared to free DOX or Se@DOX at the equivalent dose of DOX, RGDfC-Se@DOX showed greater activity to inhibit A549 cells' proliferation and migration/invasion and induce A549 cells' apoptosis. More importantly, compared with passive targeting delivery system Se@DOX, active targeting delivery system RGDfC-Se@DOX exhibited more significant antitumor efficacy in vivo.

CONCLUSION

Taken together, RGDfC-Se@DOX may be a novel promising drug candidate for the lung carcinoma therapy.

Hyaluronic acid shell and disulfide-crosslinked core micelles for in vivo targeted delivery of bortezomib for the treatment of multiple myeloma

Bortezomib (BTZ) provides one of the best treatments for multiple myeloma (MM). The efficacy of BTZ is, nevertheless, restricted by its fast clearance, low selectivity, and dose limiting toxicities. Here, we report on targeted BTZ therapy of MM in vivo by hyaluronic acid-shelled and core-disulfide-crosslinked biodegradable micelles (HA-CCMs) encapsulating lipophilized BTZ, bortezomib-pinanediol (BP). HA-CCMs loaded with 7.3 BTZ equiv. wt% exhibited a small size of 78 nm, good stability in 10% FBS, and glutathione-triggered drug release. MTT assays in CD44 positive LP-1 multiple myeloma cells revealed that BP encapsulated in HA-CCMs caused enhanced antiproliferative effect compared with free BP. Flow cytometry, confocal microscopy and MTT assays indicated BP-loaded HA-CCMs (HA-CCMs-BP) could actively target to LP-1 cells and induce high antitumor effect. Proteasome activity assays in vitro showed HA-CCMs-BP had a similar proteasome activity inhibition as compared to free BTZ at 18 h. The fluorescence imaging using Cy5-labeled HA-CCMs showed that HA-CCMs had a long elimination half-life and enhanced tumor accumulation via HA-mediated uptake mechanism. The therapeutic studies in LP-1 MM-bearing mice revealed better treatment efficacy of HA-CCMs-BP compared with free BTZ, in which HA-CCMs-BP at 3 mg BTZ equiv./kg brought about significant tumor growth inhibition and survival benefits. Loading of lipophilized BTZ into HA-shelled multifunctional micelles has emerged as an exciting approach for bortezomib therapy of MM. STATEMENT OF SIGNIFICANCE: Multiple myeloma (MM) is the second most common hematological malignancy. Bortezomib (BTZ), a potent proteasome inhibitor, provides one of the best treatments for MM. The clinical efficacy of BTZ is, however, limited by its quick clearance, poor selectivity, and significant side effects including myelosuppression and peripheral neuropathy. Here, we report on targeted BTZ therapy of MM in vivo by hyaluronic acid-shelled and core-disulfide-crosslinked biodegradable micelles (HA-CCMs) encapsulating lipophilized BTZ, bortezomib-pinanediol (BP). Our results showed that BP-loaded HA-CCMs exhibit markedly enhanced toleration, broadened therapeutic window, and significantly more effective growth suppression of CD44-overexpressed multiple myeloma in nude mice than free bortezomib. Lipophilized BTZ-loaded HA-CCMs has opened a new avenue for targeted bortezomib therapy of multiple myeloma.

Protein Nanotherapeutics as an Emerging Modality for Cancer Therapy

Protein drugs are a unique and versatile class of biotherapeutics that have not only high biological activity but also superb specificity. This rapidly evolving biotechnology has rendered it possible to produce various proteins in a large scale and reproducible way. Many proteins have demonstrated striking anticancer activities and have emerged as advanced alternatives to cytotoxic chemotherapeutic agents for cancer therapy. The clinical translation of anticancer proteins with intracellular targets is, nevertheless, severely hindered by their fast degradation in vivo, poor cell penetration, and inefficient intracellular transportation. The past few years have witnessed tremendous effort and progress in developing polymeric protein delivery nanosystems, ranging from nanoparticles, nanocapsules, nanogels, micelles, to polymersomes, for the treatment of different tumors such as lung tumors, breast tumors, ovarian cancers, and glioblastoma. These proof-of-concept studies point out that protein nanotherapeutics, with rationally designed nanovehicles, are able to overcome the extracellular barriers, cell membrane barriers, and intracellular barriers, and systemically deliver proteins into targeted cancer cells, resulting in effective cancer protein therapy. Protein nanotherapeutics appear to be a novel modality for safe and efficient cancer treatment.