De Novo Computational Design for Development of a Peptide Ligand Oriented to VEGFR-3 with High Affinity and Long Circulation.

The overexpression of VEGFR-3 is correlated with a worse prognosis in lung cancer and has been regarded as a rational target for specific drug delivery. Here, VEGFR-3 homing peptide library was efficiently established by computational design. Strong fluorescent signals of selected peptides were observed in A549 cells, but much weaker in other cells. The positive immunostaining overlapped with VEGFR-3 confirmed high affinity and selectivity of one novel peptide (CP-7). In addition, cell uptake of FITC-CP-7 peptide was significantly blocked by coinjection of excess CP-7 peptide. After labeled with 131I, the profile of pharmacology and biodistribution could be traced in vivo. The 131I-radiolabeled CP-7 peptide conjugates were >85% stable in serum over 4 h and exhibited a specific uptake of 18.04 ± 2.04% ID/g at 0.5 h after injection to high VEGFR-3 expressing A549 tumor mice. More importantly, lower uptake concentration in heart (1.06 ± 0.15% ID/g) after 2 h demonstrated the safety of peptide in vivo. The high uptake in the kidneys revealed that renal clearance was the main route of 131I-CP-7 peptide elimination from the body. Lower accumulation of 131I-CP-7 peptide in VEGFR-3 negative HeLa tumor mice further indicated that CP-7 peptide exhibited a higher tumor-homing efficiency. These studies provided a straightforward analytical access to design and screen bioactive peptide based on protein structure and revealed that CP-7 peptide represented a promising homing peptide of VEGFR-3-positive cancer in vitro and in vivo which could be used as a novel target molecule to achieve efficient drug delivery.

An Integrative Folate-Based Metal Complex Nanotube as a Potent Antitumor Nanomedicine as Well as an Efficient Tumor-Targeted Drug Carrier.

Metal-organic complexes (MOCs) are emerging developing functional materials, the different categories of metal ions and organic biomolecules provide great possibilities for the morphologies, sizes, and properties of the products. Enlightened by the previous works of folate-nickel nanotubes (FA-Ni NTs), herein, a series of metal ions are tested to coordinate with folate (FA) by the solvothermal method, among which the folate-cobalt(II) complex is formed to be a scaffold for the nanotube with the length of 150-500 nm and inner diameter of 6-11 nm, while the other metal ions fail. In vitro experiments reveal that folate-cobalt nanotubes (FA-Co NTs) have excellent antitumor activity toward tumor cells with high expression levels of folate receptor (FR), whereas they show extremely low toxicity to normal cells. Furthermore, these kinds of NTs show better antitumor ability when the anticancer drug doxorubicin is encapsulated through cell surface receptor-mediated endocytosis. Moreover, we study the fundamental pharmacokinetic profiles and biodistribution of FA-Co NTs on mice and also prove its targeting capability to tumor tissues on tumor-bearing mice using the radioactive iodine-131 (131I) tracing method. FA-Co NTs can also markedly inhibit the growth of tumor with minimal side effects when administered individually in vivo. These findings will expand the research on FA based metal complex nanomaterials as a kind of potential antitumor nanomedicine as well as a targeted drug carrier.

Differential regulation of T and B lymphocytes by PD-1 and SOCS-1 signaling in hepatitis C virus-associated non-Hodgkin's lymphoma.

HCV infection is associated with immune dysregulation and B cell Non-Hodgkins lymphoma (HCV-NHL). We have previously shown in vitro that HCV core protein differentially regulates T and B cell functions through two negative signaling pathways, programmed death-1 (PD-1) and suppressor of cytokine signaling-1 (SOCS-1). In this report, we performed a detailed immunologic analysis of T and B cell functions in the setting of HCV-NHL. We observed that T cells isolated from patients with HCV-NHL exhibited an exhausted phenotype including decreased expression of viral-specific and non-specific activation markers; whereas B cells exhibited an activated phenotype including over-expression of cell activation markers and immunoglobulins compared to healthy subjects. Individuals with HCV alone or NHL alone exhibited abnormal T and B cell phenotypes, but to a lesser extent compared to HCV-NHL. This differential activation of T and B lymphocytes was inversely associated with the expression of PD-1 and SOCS-1. Interestingly, blocking PD-1 during TCR activation inhibited SOCS-1 gene expression, suggesting that these regulatory pathways are linked in T cells. Importantly, blocking PD-1 also restored the impaired T cell functions observed in the setting of HCV-NHL. These results support a coordinated mechanism by which HCV might cause immune dysregulation that is associated to HCV-NHL.

Phenylboronic ester-modified anionic micelles for ROS-stimuli response in HeLa cell.

Smart polymers as ideal drug nanocarriers have attracted much attention due to the effective drug delivery, internalization and release once triggered by intracellular stimuli, as well as reduced cytotoxicity. We here reported the anionic micelle consisting of copolymer (PEG-b-PAsp) and a PBE (Phenylboronic Ester) group grafted, which can achieve fast response to intracellular ROS and enhanced anti-tumor activity. With this, PEG-b-PAsp-g-PBE/DOX system showed better tumor growth inhibition when studied on HeLa cell lines with high level of intracellular ROS and its subcutaneous tumor models. Additionally, the administration of PEG-b-PAsp-g-PBE/DOX did cause significantly lower systemic toxicity in comparison with free DOX. Hence, PEG-b-PAsp-g-PBE could be a highly efficient and safe nanocarrier to improve the efficacy of chemotherapeutic.

Abnormal B-cell activation associated with TALL-1 over-expression and SOCS-1 suppression during chronic hepatitis C virus infection.

Chronic hepatitis C virus (HCV) infection is associated with cirrhosis, autoimmunity and lymphoproliferative disorders. We have previously reported a differential regulation of T and B lymphocytes by HCV core protein in vitro. In this report, we employed a translational approach to characterize the activation status of peripheral B cells from individuals with chronic HCV infection and to explore potential mechanisms for B-cell dysregulation in the setting of HCV infection. In contrast to the T-cell suppression observed in HCV-infected individuals, B cells exhibit a non-specific polyclonal activation phenotype, characterized by significantly higher levels of (1) the early activation marker, CD69, (2) the costimulatory molecule, CD86, and (3) the CCR5 chemokine receptor, CD195, when compared with B cells from healthy donors in response to phytohaemagglutinin (PHA) stimulation. Importantly, tumour necrosis factor- and Apo-L-related leucocyte-expressed ligand-1 (TALL-1), also known as B-lymphocyte stimulator (BLYS), was found to be up-regulated on the surface of B cells from HCV patients in response to PHA as well as HCV core antigen stimulation. This up-regulation of TALL-1 was associated with vigorous memory B-cell responses to viral antigenic stimulation. Additionally, suppressor of cytokine signalling-1 (SOCS-1), a negative feedback immunoregulator that is inhibited in B lymphocytes by HCV core in vitro, was also inhibited in B cells from HCV patients when compared with healthy donors. These findings suggest that TALL-1 over-expression and SOCS-1 suppression are associated with aberrant B-cell activation, providing a plausible basis for the B-cell clonal expansion underlying the lymphoproliferative disorders and autoimmune phenomena observed during chronic HCV infection.

Peptide-mediated cationic micelles drug-delivery system applied on a VEGFR3-overexpressed tumor.

Copolymers as a kind of drug delivery carrier always lack targeting efficiency. So a peptide conjugated to a drug delivery system has attracted much attention for tumor-targeted nanomedicine. Thus, we here report a conjugation compound consisting of a copolymer (PEG-b-PLL) and a peptide (Cys-Ile-Gln-Pro-Phe-Tyr-Pro, CP7). For receptor-mediated endocytosis by this peptide, the CP7-PEG-b-PLL conjugation significantly enhanced the chemotherapeutic efficacy as a potent nanocarrier compared with free DOX. The CP7-PEG-b-PLL exhibited excellent pharmacokinetic behavior via a radioactive iodine-131 (I) tracing method. With this, the CP7-PEG-b-PLL/DOX system showed better tumor growth inhibition when studied on A549 cell lines and subcutaneous tumor models, but with less toxicity than free DOX. All these results suggest that the CP7-modified drug cationic micelles could represent a novel platform for successful drug delivery toward VEGFR3-overexpressed tumors.