MDDD, a 4,9-diazapyrenium derivative, is selectively toxic to glioma cells by inducing growth arrest at G0/G1 independently of p53

Diazapyrenes: interaction with nucleic acids and biological activity

The review summarizes data on the practical aspects of the interaction of nucleic acids with diazapyrene derivatives. The information on biological activity is given and the probable mechanisms underlying the action of diazapyrenes are analyzed. It contains 119 references.

Magnolol inhibits human glioblastoma cell proliferation through upregulation of p21/Cip1

Previously, we demonstrated that magnolol isolated from the bark of Magnolia officinalis has anticancer activity in colon, hepatoma, and leukemia cell lines. In this study, we show that magnolol concentration dependently (0-40 microM) decreased the cell number in a cultured human glioblastoma cancer cell line (U373) and arrested the cells at the G0/G1 phase of the cell cycle. Magnolol treatment decreased the protein levels of cyclins A and D1 and increased p21/Cip1, but not cyclins B and D3, cyclin-dependent kinase (CDK)2, CDK4, CDC25C, Weel, p27/Kip1, and p53. The CDK2-p21/Cip1 complex was increased, and the CDK2 kinase activity was decreased in the magnolol-treated U373. Pretreatment of U373 with p21/Cip1 specific antisense oligodeoxynucleotide prevented the magnolol-induced increase of p21/Cip1 protein levels and the decrease of DNA synthesis. Magnolol at a concentration of 100 microM induced DNA fragmentation in U373. Our findings suggest the potential applications of magnolol in the treatment of human brain cancers.

Toxicity and intraocular properties of a novel long-acting anti-proliferative and anti-angiogenic compound IMS2186

PURPOSE

To investigate the intraocular properties and toxicity of IMS2186, a small molecule developed as an anti-choroidal neovascularization (anti-CNV) drug.

MATERIALS AND METHODS

Cellular toxicity and mechanism of action was tested on cell lines in vitro. Intraocular studies used rabbits for drug dissolution as well as toxicity and rats for the treatment study as well as the toxicity confirmation study. Rabbits' eyes were injected with 2.5 mg of IMS2186 and observed for 36 weeks. Laser-induced CNV in rats was treated with IMS2186, Kenalog, or phosphate-buffered saline (pBS). Fluorescein angiography (FA) and immunohistochemical processing of the globes was performed.

RESULTS

The anti-proliferative IC(50) of IMS2186 for human fibroblast cells was 1.0-3.0 microM and 0.3-3.0 microM for human cancer cells; the IC(50) of IMS2186 to inhibit endothelial tube formation was 0.1-0.3 microM. The IC(50) of IMS2186 for inhibiting the production of pro-inflammatory cytokines was 0.3-1 microM. The IC(50) of IMS2186 for inhibiting macrophage migration was 1 micrM. These biological properties were not species specific. IMS2186 can be formulated as a suspension for long-lasting release and when delivered intraocularly, no intraocular toxicity was observed by slit lamp exam, fundus exam, intraocular pressure measurements, or by electroretinography. FA showed a reduction in the leakage in eyes treated with IMS2186 and triamcinolone acetonide; DAPI staining also showed significantly less cellularity in IMS2186-treated lesions as compared to PBS (p = 0.0025).

CONCLUSION

IMS2186 may be a safe intraocular therapeutic agent for intraocular proliferation and angiogenesis.