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Early detection and therapy of esophageal cancer is very important for improving the prognosis and survival rate of the patient. A theranostic agent that combines multimodal imaging with cancer therapy may be used for augmenting the visualization and treatment of the cancer. Herein, we report the synthesis of a hollow tantalum oxide (TaOx) nanoparticle that was successfully engineered by encapsulation of polypyrrole (PPy) and doxorubicin (DOX) in the core and conjugation with a near infrared fluorescence dye (NIRDye800) on the shell of the hollow TaOx nanoparticles. The as-prepared core/shell nanoparticles showed multimodal imaging features including computed tomography (CT) (for the preliminary location of the tumor), photoacoustic (for the anatomical localization of the tumor), and fluorescence imaging (for real-time monitoring of the tumor margin) and pH- and thermal-sensitive drug release. Because the early esophageal carcinoma is a type of superficial cancer, a subcutaneous model in the thigh was used for the in vivo study. The core/shell nanoparticles shows high imaging contrast between the tumor and the adjacent tissues and controllable photothermal therapy (PTT) and chemotherapy. Our results indicated that the obtained core/shell nanoparticles had significant potential in the triple-modality imaging guided precisely chemo-thermal synergetic therapy of esophageal cancer. In addition, after aerosol administration, our nanoparticles also exhibited comparable therapeutic efficacy with the intravenous administration, which is more suitable for clinical therapy of esophageal carcinoma.

SM5-1 is a humanized mouse monoclonal antibody, targeting an over-expressed membrane protein of approximately 230 kDa in hepatocellular carcinoma (HCC). SM5-1 can be used for target therapy in hepatocellular carinoma due to its ability of inhibiting cell growth and inducing apoptosis. However, the tumor inhibition efficacy of SM5-1 in HCC cancer treatment remains low. In this study, we synthesized SM5-1-conjugated gold nanoparticles (Au-SM5-1 NPs) and investigated their anticancer efficacy in HCC both in vitro and in vivo. The tumor inhibition rates of Au-SM5-1 NPs for subcutaneous tumor mice were 40.10% ± 4.34%, 31.37% ± 5.12%, and 30.63% ± 4.87% on day 12, 18, and 24 post-treatment as determined by bioluminescent intensity. In addition, we investigated the antitumor efficacy of Au-SM5-1 NPs in orthotopic HCC tumor models. The results showed that the inhibition rates of Au-SM5-1 NPs can reach up to 39.64% ± 4.87% on day 31 post-treatment determined by the bioluminescent intensity of the abdomen in tumor-bearing mice. Furthermore, three-dimensional reconstruction results of the orthotopic tumor revealed that Au-SM5-1 NPs significantly inhibited tumor growth compared with SM5-1 alone. Our results suggested that the developed Au-SM5-1 NPs has great potential as an antibody-based nano-drug for HCC therapy.

SM5-1 is a humanized mouse antibody which has a high binding specificity for a membrane protein of about 230 kDa overexpressed in hepatocellular carcinoma (HCC), melanoma and breast cancer. In this study, SM5-1-conjugated poly d, l (lactide-coglycolide) (PLA) PLA containing Cy7 (PLA-Cy7-SM5-1) was prepared to study the targeting specificity of the bioconjugate to HCC-LM3-fLuc cell. Then, SM5-1-conjugated PLA containing 5-fluorouracil (5-FU) (PLA-5FU-SM5-1) and PLA containing 5-FU (PLA-5FU) were prepared for treatment of subcutaneous HCC-LM3-fLuc tumor mice. The results showed that PLA-5FU-SM5-1, PLA-5FU and 5-FU induced a 45.07%, 23.56% and 19.05% tumor growth inhibition rate, respectively, on day 31 post-treatment as determined by bioluminescent intensity. In addition, in order to evaluate the antitumor efficacy of PLA-5FU-SM5-1, HCC-LM3-fLuc cells were injected into the liver to establish the experimental orthotopic liver tumor models. The experiments showed that PLA-5FU-SM5-1, PLA-5FU and 5-FU induced a 53.24%, 31.00%, and 18.11% tumor growth inhibition rate, respectively, on day 31 post-treatment determined by the bioluminescent intensity of the abdomen in tumor-bearing mice. Furthermore, we have calculated the three-dimensional location of the liver cancer in mice using a multilevel adaptive finite element algorithm based on bioluminescent intensity decay calibration. The reconstruction results demonstrated that PLA-5FU-SM5-1 inhibited the tumor rapid progression, which were consistent with the results of subcutaneous tumor mice experiments and in vitro cell experiment results.

In this study, a fast and robust reconstruction method based on the separable approximation and the adaptive regularization is presented for fluorescence molecular tomography. The subproblems can be established and solved efficiently through separable approximation, and the convergence process can be also accelerated by adaptive regularization. As is well known, the regularization parameter has an important impact on the results, and finding the optimal or near-optimal regularization parameter automatically is an challenging task. To solve this problem, the regularization parameter in the proposed method is updated heuristically instead of being determined manually or empirically. This adaptive regularization strategy of the proposed method can perform accurate reconstruction almost without worrying about the choice of the regularization parameter. By contrast, improper choice of the regularization parameter may cause larger location errors for the three contrasting methods. The proposed method is proved robust and insensitive to parameters, which can improve the reconstruction accuracy. Moreover, the proposed method was about 1-2 orders of magnitude faster than the contrasting methods commonly used in fluorescence tomography reconstruction. Furthermore, reliable performance on different initial unknown values and different noise levels was also investigated. Finally, the potential of the proposed method in a practical application was further validated by the physical experiment with a mouse model. (C) 2012 Elsevier B.V. All rights reserved.