Vaccination with B7-1+ tumor and anti-adhesion therapy with RGD pseudo-peptide (FC-336) efficiently induce...

Area of Science:

• Immunology
• Cancer Research
• Oncology

Background:

• Expression of costimulatory ligand B7-1 on tumor cells can reduce metastasis and induce anti-tumor immunity.
• Previous studies showed B7-1 expression on B16-BL6 melanoma reduced lung metastasis in mice.

Purpose of the Study:

• To investigate the efficacy of irradiated B7-1 transfected tumor cells as a vaccine against established metastasis.
• To evaluate if combining B7-1 expression with anti-adhesion peptide FC-336 enhances antimetastatic effects.

Main Methods:

• Immunization with X-irradiated B7-1 transfectants after intravenous injection of B7-1- parental B16-BL6 cells.
• Vaccination with irradiated B7-1 transfectants after primary tumor excision to assess spontaneous metastasis inhibition.
• Administration of anti-adhesion peptide FC-336 to evaluate its effect on spontaneous metastasis.
• Combined treatment using B7-1 transfected tumor vaccine and FC-336 therapy.

Main Results:

• Immunization with irradiated B7-1 transfectants inhibited lung metastasis.
• Vaccination post-primary tumor excision significantly inhibited spontaneous lung metastasis compared to controls.
• Mock transfectant immunization did not inhibit spontaneous metastasis.
• FC-336 administration inhibited spontaneous metastasis by interfering with tumor invasion, migration, and adhesion.
• Combined B7-1 vaccine and FC-336 therapy showed augmented antimetastatic effects in both experimental and spontaneous metastasis models.

Conclusions:

• Irradiated B7-1 transfected tumor cells serve as an effective vaccine against lung metastasis.
• Combined therapy of B7-1 tumor vaccine and FC-336 anti-adhesion treatment synergistically enhances antimetastatic efficacy.
• B7-1 and FC-336 mediated inhibition of metastasis likely involve distinct mechanisms regulating tumor-host interactions.