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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.

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 (IC

Brain metastases are a most disturbing situation for breast cancer patients as there is basically no adequate treatment available. Any potential drug formulation has to be able to cross the blood-brain barrier (BBB) and specific to metastatic brain tumors without causing unacceptable adverse effects. Here, we developed transferrin-functionalized chimeric polymersomes carrying siRNA against polo-like kinase 1 (Tf@TBP-CPs-siPLK1) for treating brain metastatic MDA-MB 231 triple negative breast cancer (TNBC) xenografts in mice. To facilitate the loading of siPLK1, chimaeric polymersomes (CPs) were designed with spermine in the watery core and transferrin-binding peptide (TBP) at the surface, enabling attachment of transferrin after the siRNA loading step and thereby circumventing interference of transferrin with siRNA loading. Tf@TBP-CPs-siPLK1 encapsulating 3.8 wt% siRNA had a mean size of about 50 nm and a neutral zeta potential in phosphate buffer (PB). By virtue of the presence of transferrin, Tf@TBP-CPs demonstrated greatly (ca. 5-fold) enhanced internalization in MDA-MB 231 cells and transcytosis in the endothelial (bEnd.3) monolayer model in vitro as well as markedly improved accumulation in the orthotopically xenografted MDA-MB 231 tumor in the brain in vivo compared with control CPs lacking transferrin, supporting that transferrin mediates efficient BBB penetration and high specificity towards MDA-MB 231 cells. As a result, Tf@TBP-CPs-siPLK1 effectively inhibited tumor progression and prolonged the lifespan of the mice significantly. Selective transferrin coating appears to be a particularly facile strategy to fabricate BBB-permeable and targeted vesicles for potent RNAi therapy of brain metastatic breast cancer.

Sorafenib (SF) is an FDA-approved molecular-targeted drug for treating hepatocellular carcinoma (HCC). SF, however, suffers from poor water solubility, low bioavailability, dose-limiting side effects, and possible drug resistance. Here, we report on apolipoprotein E peptide-decorated disulfide-cross-linked micellar SF (ApoE-Ms-SF) as a targeted and intelligent formulation for HCC therapy. ApoE-Ms-SF was prepared with a good SF loading of 7.0 wt %, small size (37 nm), high stability, and reduction-triggered drug release from poly(ethylene glycol)-b-poly(e-caprolactone-co-dithiolane trimethylene carbonate)-mefenamate (PEG-P(CL-DTC)-MA) and ApoE-modified ApoE-PEG-P(CL-DTC) block copolymers. MTT assays in low-density lipoprotein receptors (LDLRs) overexpressing SMMC-7721 human liver cancer cells showed ApoE density-dependent antitumor potency of ApoE-Ms-SF, in which 7.5% ApoE led to the best antitumor effect (IC50: 8.5 vs 23.3 μg/mL for free SF). Confocal studies, flow cytometry, western blot, and apoptotic assays illustrated clearly a more efficient uptake of ApoE-Ms than nontargeted Ms by SMMC-7721 cells as well as lower phosphorylated extracellular signal-regulated kinase protein level and better cell apoptosis caused by ApoE-Ms-SF compared with Ms-SF and free SF. ApoE-Ms-SF revealed a long circulation time (elimination half-life = 6.8 h). DiR-loaded ApoE-Ms showed a significantly higher accumulation in SMMC-7721 tumor than the nontargeted counterpart. The therapeutic outcomes in the orthotopic SMMC-7721 tumor models demonstrated that ApoE-Ms-SF reduced SF-associated side effects and brought about enhanced angiogenesis inhibition and tumor apoptosis compared to free SF and Ms-SF controls, leading to a better treatment of HCC.

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 α

Future healthcare requires development of novel theranostic agents that are capable of not only enhancing diagnosis and monitoring therapeutic responses but also augmenting therapeutic outcomes. Here, a versatile and stable nanoagent is reported based on poly(ethylene glycol)-b-poly(l-thyroxine) (PEG-PThy) block copolypeptide for enhanced single photon emission computed tomography/computed tomography (SPECT/CT) dual-modality imaging and targeted tumor radiotherapy in vivo. PEG-PThy acquired by polymerization of l-thyroxine-N-carboxyanhydride (Thy-NCA) displays a controlled Mn , high iodine content of ≈49.2 wt%, and can spontaneously form 65 nm-sized nanoparticles (PThyN). In contrast to clinically used contrast agents like iohexol and iodixanol, PThyN reveals iso-osmolality, low viscosity, and long circulation time. While PThyN exhibits comparable in vitro CT attenuation efficacy to iohexol, it greatly enhances in vivo CT imaging of vascular systems and soft tissues. PThyN allows for surface decoration with the cRGD peptide achieving enhanced CT imaging of subcutaneous B16F10 melanoma and orthotopic A549 lung tumor. Taking advantages of a facile iodine exchange reaction, 125 I-labeled PThyN enables SPECT/CT imaging of tumors and monitoring of PThyN biodistribution in vivo. Besides, 131 I-labeled and cRGD-functionalized PThyN displays remarkable growth inhibition of the B16F10 tumor in mice (tumor inhibition rate > 89%). These poly(l-thyroxine) nanoparticles provide a unique and versatile theranostic platform for varying diseases.

Emerging tumor treatment demands high sensitivity and high-spatial resolution diagnosis in combination with targeted therapy. Here, we report that iodine-rich polymersomes (I-PS) enable versatile single-photon emission computed tomography (SPECT)/computed tomography (CT) dual-modal imaging and potent radioisotope therapy for breast cancer in vivo. Interestingly, I-PS could be easily and stably labeled with radioiodine, 125I and 131I. Dynamic light scattering and transmission electron microscopy showed that 125I-PS had a size of 106 nm and vesicular morphology, similar to those of the parent I-PS. Methyl thiazolyl tetrazolium assays displayed that I-PS and 125I-PS were noncytotoxic, whereas 131I-PS caused significant death of 4T1 cells at 5 mg PS/mL with a radioactivity of 12 μCi. Pharmacokinetic and biodistribution studies showed that 125I-PS has a prolonged circulation and distributes mainly in tumor and the reticuloendothelial system. The intravenous injection of 125I-PS to 4T1 murine breast tumor-bearing mice allowed simultaneous high sensitivity and high-spatial resolution imaging of tumor by SPECT and CT, respectively. The therapeutic studies revealed that 131I-PS could effectively retard the growth of 4T1 breast tumor and significantly prolong mice survival time. The hematoxylin and eosin staining assay proved that 131I-PS induced tumor cell death. I-PS emerges as a robust and versatile platform for dual-modal imaging and targeted radioisotope therapy.

The clinical success of nanomedicines demands on the development of simple biodegradable nanocarriers that can efficiently and stably encapsulate chemotherapeutics while quickly release the payloads into target cancer cells. Herein, we report that cRGD-decorated biodegradable polytyrosine nanoparticles (cRGD-PTN) boost encapsulation and targeted delivery of doxorubicin (DOX) to colorectal cancer in vivo. The co-assembly of poly(ethylene glycol)-poly(L-tyrosine) (PEG-PTyr) and cRGD-functionalized PEG-PTyr (mol/mol, 80/20) yielded small-sized cRGD-PTN of 70 nm. Interestingly, cRGD-PTN exhibited an ultra-high DOX encapsulation with drug loading contents ranging from 18.5 to 54.1 wt%. DOX-loaded cRGD-PTN (cRGD-PTN-DOX) was highly stable against dilution, serum, and Triton X-100 surfactant, while quickly released DOX in HCT-116 cancer cells, likely resulting from enzymatic degradation of PTyr. Flow cytometry, confocal microscopy and MTT assays displayed that cRGD-PTN-DOX was efficiently internalized into αvβ5 overexpressing HCT-116 colorectal cancer cells, rapidly released DOX into the nuclei, and induced several folds better antitumor activity than non-targeted PTN-DOX and clinically used liposomal DOX (Lipo-DOX). SPECT/CT imaging revealed strong tumor accumulation of 125I-labeled cRGD-PTN, which was 2.8-fold higher than 125I-labeled PTN. Notably, cRGD-PTN-DOX exhibited over 5 times better toleration than Lipo-DOX and significantly more effective inhibition of HCT-116 colorectal tumor than non-targeted PTN-DOX control, affording markedly improved survival rate in HCT-116 tumor-bearing mice with depleting side effects at 6 or 12 mg DOX equiv./kg. cRGD-PTN-DOX with great simplicity, robust drug encapsulation and efficient nucleic drug release appears promising for targeted chemotherapy of colorectal tumor.

Small interfering RNA (siRNA) is considered a highly specific and potent biotherapeutic that holds tremendous potential for the treatment of various diseases. The clinical translation of siRNA is, however, greatly impeded by the lack of safe and efficient delivery vehicles in vivo. Here, the development of selective cell penetrating peptide (CPP33)-functionalized chimeric lipopepsomes (CPP33-CLP) for efficient encapsulation and selective delivery of polo-like kinase 1 specific siRNA (siPLK1) to orthotopic A549 human lung tumor in vivo is reported. Interestingly, siRNA is tightly encapsulated into CPP33-CLP with a superb encapsulation efficiency of over 95% owing to the thick strong electrostatic interactions. Notably, siPLK1-loaded CPP33-CLP (siPLK1-CPP33-CLP) is selectively internalized by A549 human lung cancer cells, efficiently escapes from endosomes, and swiftly releases siRNA into the cytoplasm, affording a significant sequence-specific gene silencing in vitro. Moreover, siPLK1-CPP33-CLP exhibits prolonged blood circulation, enhanced tumor accumulation, effective suppression of tumor growth, and considerably elevated survival time of orthotopic A549 human lung tumor-bearing nude mice. These chimeric lipopepsomes appear as an attractive and potent nanoplatform for safe and targeted siRNA delivery.

The catecholic amino acid 3,4-Dihydroxyphenyl-l-alanine (DOPA) is believed to be responsible for the water-resistant adhesive characteristics of mussel adhesive proteins (MAPs). In this paper, the synthesis of three-armed poly(ethylene glycol)s with dopamine endgroups (PEG-DOPAs) using acylation reaction and Michael addition reaction was described, and PEG-DOPAs was used as bioadhesive under the UV irradiation. The structures of PEG-DOPAs were characterized by FTIR, (1)H NMR spectroscopy. The adhesion properties of PEG-DOPAs were investigated and results were significantly superior to 0.05MPa of the commercially available fibrin adhesives. Moreover, the adhesive strength of PEG-DOPAs (Mw 3000) increased from 0.587MPa to 1.82MPa, PEG-DOPAs (Mw 20,000) increased from 0.338MPa to 1.92MPa with the elongation of the binding time, severally. The photopolymerization kinetic study was taken to evaluate gelation time of bioadhesive indirectly. The cytotoxicity of photocured PEG-DOPAs hydrogels for L929 cells was evaluated by the fluorescence microscopy and MTT (3-[4-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide; Thiazolyl blue) assay, respectively. The results showed that PEG-DOPAs were biocompatible and less cytotoxicity toward the growth of L929 cells. The swelling properties of PEG-DOPAs hydrogels were also tested. PEG-DOPAs (3000) reached swelling equilibrium within 2h at 37°C, and PEG-DOPAs (20,000) within 6h at 37°C.