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The development of robust photothermal agents for near-infrared (NIR) imaging is a great challenge. Herein, we report the design and synthesis of a new photothermal agent, based on the aza-boron-dipyrromethene framework (azaBDP). This compound possessed excellent photostability and high photothermal-conversion efficiency (50 %) under NIR laser irradiation. When the photothermal properties of this compound were utilized for tumor inhibition, stable long-term fluorescence was observed in living animals. Photothermal treatment efficiently suppressed tumor growth, as evidenced by in vitro and in vivo experiments. Furthermore, NIR emission could be detected by using an imaging system and therapeutic self-monitoring was achieved by using NIR imaging.

A novel series of tetrahydroquinolines containing acetohydrazide, oxopyrazole, oxothioxodihydropyrazole, and thioxotriazole have been synthesized. Antileishmanial, antitumor, and cytotoxicity activities of synthesized compounds were evaluated in vitro. Antileishmanial activity of the most synthesized compounds showed tremendous activity towards Leishmania major. Most of the test compounds exhibited significant level of tumor inhibition. The tetrahydropyrano[2,3-b]quinolin-2-one 6 and 4-oxo-4H-pyrazol-3-yloxytetrahydroquinoline-3-carbonitrile derivatives 18 showed 100% tumor inhibition comparable with standard drug vincristine (100% tumor inhibition). Tetrahydroquinolines under investigation showed cytotoxicity with LD50 values in the range 0.56–3.01 μg/mL compared with standard drug MS-222 with LD50 value of 4.30 μg/mL. The presence of a pyrazole ring markedly improved the activity profiles of tetrahydroquinoline. All newly synthesized compounds were characterized by IR, 1H NMR, and MS.

Targeted drug delivery systems (TDDSs) provide a promising approach to overcome the side effect of traditional chemotherapy by specific tumor targeting and drug release. Hyaluronan (HA), as a selective CD44 targeting group, has been widely used in TDDSs for chemotherapy. However, different molecular weight HAs would demonstrate different binding ability to CD44, which may result in different therapeutic effects. Herein, a silica/hydroxyapatite (MSNs/HAP) hybrid carrier loaded with anticancer drug doxorubicin (DOX) (DOX@MSNs/HAP) is fabricated. HA and oligo HA (oHA) are coated onto the nanoparticles (HA‐DOX@MSNs/HAP, oHA‐DOX@MSNs/HAP), respectively, to investigate their performance in tumor targeting ability. oHA‐DOX@MSNs/HAP shows much higher efficiency cellular uptake and drug release in tumor regions due to more effective CD44 targeting of oHA. Thus, the anticancer effect of oHA‐DOX@MSNs/HAP is significantly enhanced compared to HA‐DOX@MSNs/HAP, as demonstrated in a tumor‐bearing mouse model. This study may enable the rational design of nanodrug systems for future tumor‐targeted chemotherapy.

The combination of Endostatin (ES) and Herpes Simplex Virus thymidine kinase (HSV‐TK) gene therapy is known to have antitumor activity in bladder cancer. The potential effect of ES and TK therapy in glioma has not yet been investigated. In this study, pTK‐internal ribosome entry site (IRES), pIRES‐ES, and pTK‐IRES‐ES plasmids were constructed; pIRES empty vector served as the negative control. The recombinant constructs were transfected into human umbilical vein endothelial cells (HUVECs) ECV304 and C6 rat glioma cell line. Ganciclovir (GCV) was used to induce cell death in transfected C6 cells. We found that ECV304 cells expressing either ES or TK‐ES showed reduced proliferation, decreased migration capacity, and increased apoptosis, as compared to untransfected cells or controls. pTK‐IRES‐ES/GCV or pTK‐IRES/GCV significantly suppressed cell proliferation and induced cell apoptosis in C6 cells, as compared to the control. In addition, the administration of pIRES‐ES, pTK‐IRES/GCV, or pTK‐IRES‐ES/GCV therapy improved animal activity and behavior; was associated with prolonged animal survival, and a lower microvessel density (MVD) value in tumor tissues of C6 glioma rats. In comparison to others, dual gene therapy in form of pTK‐IRES‐ES/GCV had a significant antitumor activity against C6 glioma. These findings indicate combined TK and ES gene therapy was associated with a superior antitumor efficacy as compared to single gene therapy in C6 glioma.

Angiogenesis is a prerequisite of tumor growth and metastasis and, thus, anti-angiogenesis treatment has become an important part of cancer therapy. A 15-amino acid peptide of the fibrinogen α chain, fibrinostatin, was previously found in serum samples of gastric cancer patients. Herein we demonstrated that fibrinostatin has anti-angiogenesis activity in several angiogenesis models and it reduces tumor growth in mouse xenografts and allografts. Increased tumor necrosis and reduced microvessel density in tumors were observed in mouse xenograft models. Fibrinostatin inhibited proliferation and induced apoptosis in HUVEC, but not in cancer cells. In addition, fibrinostatin specifically entered HUVEC. Fibrinostatin also prevented migration, adhesion and tubule formation of HUVEC in vitro. A single-dose acute toxicity testing and a repeated-dose chronic toxicity study in the mouse, rat and monkey indicated that fibrinostatin had a wide margin of safety. Taken together, fibrinostatin shows promise as a potential anti-angiogenesis therapeutic agent.

Bioinspired tryptophan-rich peptide dendrimers (TRPDs) are designed as a new type of dendritic peptide drugs for efficient tumor therapy. The TRPDs feature a precise molecular structure and excellent water solubility and are obtained in a facile process. Based on the unique features of peptide dendrimers, including highly branched structures, abundant terminal groups, and globular-protein-like architectures, the therapeutic dendrimers show significant supramolecular interactions with DNA through the tryptophan residues (indole rings and amino groups). Further experimental results indicate that TRPDs are efficient antitumor agents both in vitro and in vivo.

Highly precise control of molecular structure for developing efficient anticancer drug delivery is challenging. Our method reported herein can satisfy the need for building novel hybrid molecule; this molecule serves as a built-in transformer that changes its molecular configuration from a pin-shaped arrangement to a dog bone-shaped arrangement. This approach led to a significant increase in the efficiency of tumor inhibition. Copyright © 2014 John Wiley & Sons, Ltd.

Endohedral metallofullerenes exhibit combined properties from carbon cages as well as internal metal moieties and have great potential in a wide range of applications as molecule materials. Along with the breakthrough of mass production of metallofullerenes, their applied research has been greatly developed with more and more new functions and practical applications. For gadolinium metallofullerenes, their water-soluble derivatives have been demonstrated with antitumor activity and unprecedented tumor vascular-targeting therapy. Metallofullerene water-soluble derivatives also can be applied to treat reactive oxygen species (ROS)-induced diseases due to their high antioxidative activity. For magnetic metallofullerenes, the internal electron spin and metal species bring about spin sensitivity, molecular magnets, and spin quantum qubits, which have many promising applications. Metallofullerenes are significant candidates for fabricating useful electronic devices because of their various electronic structures. This Review provides a summary of the metallofullerene studies reported recently, in the fields of tumor inhibition, tumor vascular-targeting therapies, antioxidative activity, spin probes, single-molecule magnets, spin qubits, and electronic devices. This is not an exhaustive summary and there are many other important study results regarding metallofullerenes. All of this research has revealed the irreplaceable role of metallofullerene materials.

Photothermal–radiotherapy (PT–RT) is an effective strategy for relieving hypoxia‐related radiotherapy resistance and inducing tumor‐specific cell apoptosis/necrosis. Nevertheless, limited tissue penetration of near‐infrared (NIR) laser and the serious side effects of high‐dose radiation severely hinder its applications for deep tumors. An interventional photothermal–brachytherapy (IPT–BT) technology is proposed here for the internal site‐specific treatment of deep tumors. This technology utilizes a kind of biodegradable honeycomb‐like gold nanoparticles (HGNs) acting as both internal photothermal agents and radiosensitizers. A high tumor inhibition rate of 96.6% is achieved in SW1990 orthotopic pancreatic tumor‐bearing mice by HGNs‐mediated IPT–BT synergistic therapy. Interestingly, this approach effectively causes double‐stranded DNA damage and improves the oxygen supply and the penetration of nanoparticles inside the tumor. Therefore, it is believed that this strategy may open up a new avenue for PT–RT synergistic therapy of deep malignant tumors and has a significant impact on the future clinical translation.

Endostatin, a 20-kDa C-terminal proteolytic fragment of collagen XVIII, is a specific endogenous angiogenesis inhibitor discovered more than a decade. The structure, stability, and mechanism of actions of endostatin have been extensively investigated during the past 12 years, among which controversial reports remain unclarified. The mysteries include the following: 1) Why controversial efficacies were observed with endostatin regarding tumor inhibition? Particularly, why does an N-terminal modified endostatin show good clinical responses in China, whereas the clinical trials of the wild type endostatin were terminated at the early stage of phase II in the USA? 2) What is the contribution of zinc-binding to the stability and biological functions of endostatin? 3) Why does insoluble endostatin shrink tumors? 4) How to ensure that endostatin is correctly refolded? 5) How does endostatin exert its biological functions? Recent progress regarding the biophysical properties, biological functions, signaling pathways, and clinical trials of endostatin are reviewed here. Surprising findings show that the integrity of the N-terminal sequence, the capability of zinc-binding, and the correct folding are three essential elements for assurance of structural stability and biological functions of endostatin. This review provides clues to understand the mysteries of endostatin and its derivatives.

Our previous cellular experiments demonstrated that 100 Hz magnetic field (MF) was effective at enhancing apoptosis of liver cancer cells BEL-7402 induced by X-ray irradiation. This study was performed to further explore the possible synergism between 100 Hz MF and X-ray in treatment of hepatoma-implanted Balb/c mice. 100 Hz MF exposure with a mean flux density of 0.7 mT was performed inside an energized solenoid coil. Six MV X-ray irradiation was generated using a linear accelerator. Tumor growth and survival of mice implanted with H22 cells were evaluated by measuring the tumor diameters and overall days of survival. Six groups treated with 100 Hz MF or X-ray alone or a combination of MF and X-ray were examined. Furthermore, the effects of different numbers of MF exposure periods on tumor growth and mice survival were examined when combined with 4 Gy X-ray. Data referring to overall survival days and tumor diameters of the above groups were compared using log-rank test and Student's t-test. Our results showed that five periods of combined 100 Hz MFs and 4 Gy X-ray could significantly extend the overall days of survival and reduce the tumor size compared to MF or X-ray alone. Also, a greater number of 100 Hz MF exposure periods could further improve the survival and inhibit tumor growth in hepatoma-implanted mice when combined with 4 Gy X-ray. In conclusion, these findings suggested that 100 Hz MF could possibly synergize with 4 Gy X-ray in terms of survival improvement and tumor inhibition in hepatoma-implanted mice. Bioelectromagnetics 32:322–324, 2011. © 2011 Wiley-Liss, Inc.

In connection with a mechanistic study of macrolide ring closure1,2 it was necessary to prepare a number of symmetrically substituted 2,2′-dipyridyl disulfides. Members of this class have found useful applications in analytical thiol determination,3 metal chelation studies,4 and tumor inhibition studies.5 In view of the potential usefulness of these compounds in these and other areas, their synthesis is described below. Most of the compounds described herein are new;6 two of them (III and IV) are known compounds prepared by a new route.