Specific effects of bortezomib against experimental malignant pleural effusion: a preclinical study

• Published in: Molecular cancer 2010-03, Vol.9 (1), p.56-56, Article 56
• Main Authors: Psallidas, Ioannis, Karabela, Sophia P, Moschos, Charalampos, Sherrill, Taylor P, Kollintza, Androniki, Magkouta, Sophia, Theodoropoulou, Panagiota, Roussos, Charis, Blackwell, Timothy S, Kalomenidis, Ioannis, Stathopoulos, Georgios T
• Format: Article
• Language: English
• Subjects: Animals; Boronic Acids - pharmacology; Boronic Acids - therapeutic use; Bortezomib; Cell Line, Tumor; Cell Proliferation - drug effects; Development and progression; Down-Regulation - drug effects; Drug Screening Assays, Antitumor; Drug therapy; Gene Expression Regulation, Neoplastic - drug effects; Health aspects; Inflammation - complications; Inflammation - drug therapy; Inflammation Mediators - metabolism; Lung cancer; Lung Neoplasms - complications; Lung Neoplasms - drug therapy; Mice; Mice, Inbred C57BL; Neoplasms, Experimental - complications; Neoplasms, Experimental - drug therapy; Neovascularization, Pathologic - complications; Neovascularization, Pathologic - drug therapy; NF-kappa B - metabolism; Pleural Effusion, Malignant - complications; Pleural Effusion, Malignant - drug therapy; Proteasome Endopeptidase Complex - metabolism; Proteasome Inhibitors; Pyrazines - pharmacology; Pyrazines - therapeutic use
• ISSN: 1476-4598; 1476-4598
• DOI: 10.1186/1476-4598-9-56

We have previously shown that nuclear factor (NF)-kappaB activation of mouse Lewis lung carcinoma (LLC) specifically promotes the induction of malignant pleural effusions (MPE) by these cells. In the present studies we hypothesized that treatment of immunocompetent mice with bortezomib tailored to inhibit cancer cell NF-kappaB activation and not proliferation specifically inhibits MPE formation by LLC cells. Treatment of LLC cells with low concentrations of bortezomib (100 ng/ml) inhibited NF-kappaB activation and NF-kappaB-dependent transcription, but not cellular proliferation. Bortezomib treatment of immunocompetent C57BL/6 mice bearing LLC-induced subcutaneous tumors and MPEs significantly blocked tumor-specific NF-kappaB activation. However, bortezomib treatment did not impair subcutaneous LLC tumor growth, but was effective in limiting LLC-induced MPE. This specific effect was evidenced by significant reductions in effusion accumulation and the associated mortality and was observed with both preventive (beginning before MPE formation) and therapeutic (beginning after MPE establishment) bortezomib treatment. The favorable impact of bortezomib on MPE was associated with suppression of cardinal MPE-associated phenomena, such as inflammation, vascular hyperpermeability, and angiogenesis. In this regard, therapeutic bortezomib treatment had identical favorable results on MPE compared with preventive treatment, indicating that the drug specifically counteracts effusion formation. These studies indicate that proteasome inhibition tailored to block NF-kappaB activation of lung adenocarcinoma specifically targets the effusion-inducing phenotype of this tumor. Although the drug has limited activity against advanced solid lung cancer, it may prove beneficial for patients with MPE.