Objective: To study the antitumor effects and mechanism of cationic liposome-mediated SurvivinT34A mutants in mice with pulmonary metastases of melanoma B16.
Methods: The pulmonary metastases model of B16, a mouse melanoma cell line, was established by the injection of B16 cell suspension via tail vein of C57BL/6 mouse. 3 days later, 18 tumor-bearing mice were randomly divided into 3 groups, which were intravenously administrated with normal saline (100 microL), vector (5 microg DNA, 100 microL) and recombinant plasmid SurvivinT34A mutants (5 microg DNA, 100 microL) every other day for five doses, respectively. After 28 days, the mice were sacrificed, the lung tissue was weighted, and the number of metastasis foci on lung surface was counted and measured. Then, pathological change of lung tissue was studied with HE stainning. The number of apoptotic cells in tumor tissues was assessed by TUNEL assay.
Results: Compared with the control, mice treated with mSurvivnT34A had an intact structure of lung, with significant reduction in the number of metastasis foci on lung surface (P < 0.05), and high level of apoptosis in tumor tissue (P < 0. 05).
Conclusion: Recombinant plasmid SurvivinT34A mutants (pORF9-mSurvivinT34A) may inhibit the formation of pulmonary metastases of melanoma.