Background: This study was designed to evaluate the antitumor activity of low-molecular-weight β-glucan (LMBG) produced by gamma irradiation (50 kGy), using in vivo and in vitro models.
Results: The results indicate that treatment with LMBG increased the proliferation of murine peritoneal macrophages, and their production of tumor necrosis factor α and nitric oxide, to a greater extent than treatment with high-molecular-weight β-glucan (HMBG). The activation of peritoneal macrophages by LMBG was mediated by both mitogen-activated protein kinases and nuclear factor-κB signaling. Interestingly, when administered prophylactically, LMBG significantly inhibited tumor growth and lung metastasis in mice injected with B16BL6 melanoma cells compared with the HMBG-treated group. In comparison with HMBG treatment, LMBG treatment also elevated cell proliferation, cytokine (interferon-γ and interleukin-2) production, and CD8(+) T cell populations in splenocytes from tumor-bearing mice.
Conclusion: These data indicate that LMBG is important in eliciting antitumor activity through a non-specific immune response and may play a major role as a value-added product in the medical industry.
Keywords: cancer treatment; gamma irradiation; immune response; β-glucan.
© 2015 Society of Chemical Industry.