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San Diego, CA, United States

Momiyama M.,NtiCancer Inc. | Momiyama M.,University of California at San Diego | Momiyama M.,Yokohama City University | Suetsugu A.,NtiCancer Inc. | And 5 more authors.
Anticancer Research | Year: 2013

Novel subcellular imaging technology has been developed in order to visualize drug efficacy on single cancer cells in the brain of mice in real time. The efficacy of temozolomide on cancer cells in the brain was determined by observation of subcellular cancer-cell dynamics over time through a craniotomy open window. Dual-color U87 human glioma and Lewis lung carcinoma (LLC) cells, expressing green fluorescent protein (GFP) in the nucleus and red fluorescent protein (RFP) in the cytoplasm, were imaged through the craniotomy open window 10 days after treatment with temozolomide (100 mg/kg i.p. for five consecutive days). After treatment, dual-color cancer cells with fragmented nuclei were visualized, indicating apoptosis. GFP-expressing apoptotic bodies and the destruction of RFP-expressing cytoplasm were also visualized. In addition, the terminal deoxynucleotidyltransferase- mediated deoxyuridine triphosphate nick-end labeling (TUNEL) assay was used to confirm apoptosis visualized by imaging of the behavior of GFP-labeled cancercell nuclei. Tumor volume in the treated group was significantly smaller than in the control group (at day 19, p<0.001). The present study demonstrates technology capable of subcellular real-time imaging in the brain that reports induction of cancercell apoptosis by therapeutic treatment. More effective drugs for brain cancer and brain metastasis can be screened and can be identified with this technology. Source

Momiyama M.,NtiCancer Inc. | Momiyama M.,Yokohama City University | Momiyama M.,University of California at San Diego | Hiroshima Y.,NtiCancer Inc. | And 11 more authors.
Anticancer Research | Year: 2013

Malignant glioma is the most common type of primary central nervous system cancer. Gliomas are very difficult to completely resect due to their invasiveness. In the present study, we compared fluorescence-guided and standard bright-light resection of a human glioma orthotopically implanted in nude mice. U87 human glioma cells, expressing red fluorescent protein (RFP), were injected stereotactically into the nude mouse brain through a craniotomy open window. Two weeks after cancer-cell implantation, gliomas were resected under fluorescence guidance or under bright light. U87-RFP tumors were clearly visualized with a long-working distance fluorescence microscope. Almost all cancer cells were removed using fluorescence-guided navigation without damage to the brain tissue. In contrast, brain tumors were difficult to visualize under bright light and many residual cancer cells remained in the brain after bright-light surgery. Fluorescence-guided surgery significantly extended the survival of the mice compared to those who underwent bright-light surgery. These results suggest that fluorescence-guided surgery has significant potential for brain cancer treatment. Source

Tome Y.,NtiCancer Inc. | Tome Y.,University of California at San Diego | Tome Y.,University of Ryukyus | Zhang Y.,NtiCancer Inc. | And 9 more authors.
Anticancer Research | Year: 2013

We developed the tumor-targeting strain Salmonella typhimuium A1-R (A1-R) and have shown it to be active against a number of tumor types in nude mice. However, in immunocompetent mice, dosing of A1-R has to be adjusted to avoid toxicity. In the present study, we developed a strategy to maximize efficacy and minimize toxicity for A1-R tumor-targeting in immunocompetent mice implanted with the Lewis lung carcinoma. A small primer dose of A1-R was first administered (1×106 colony forming unit [cfu] i.v.) followed by a high dose (1×107 cfu i.v.) four hours later. The primer-dose strategy resulted in smaller tumors and no observable side-effects compared to treatment with high-dose-alone. The serum level of tumor necrosis factor (TNF-α) was elevated in the mice treated with primer dose compared to mice only given the high dose. Tumor vessel destruction was enhanced by primer dosing of A1-R in immuno-competent transgenic mice expressing the nestin-driven green fluorescent protein, which is selectively expressed in nascent blood vessels. The primer-dose may activate TNF-α and other cytokines in the mouse, necessary for invasion of the tumor by the bacteria, as well as enhance tumor vessel destruction, thereby allowing a subsequent therapeutic dose to be effective and safe. The results of the present study suggest effective future clinical strategies of bacterial treatment of cancer. Source

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