Combination of Fasl and GM‐CSF confers synergistic antitumor immunity in an in vivo model of the murine Lewis lung carcinoma

Abstract

Gene transfer of Fas ligand (FasL) to tumor cells has been demonstrated to inhibit tumor growth in vivo, and neutrophils are primarily responsible for this immunoprotection. The granulocyte–macrophage colony stimulating factor (GM‐CSF) secreted by tumor vaccine can recruit dendritic cells (DCs) for efficient antigen presentation to T cells that generate the tumor‐specific response. To investigate whether the combination of FasL and GM‐CSF can efficiently suppress tumor growth, we have established Lewis lung carcinoma (LLC‐1) cells that are transduced with GM‐CSF (LLC/GM‐CSF), FasL (LLC/FasL) or both genes (LLC/FasL/GM‐CSF) to test their tumorigenic potential in vivo. Mice inoculated with LLC/GM‐CSF display high survival rates along with reduction of tumor growth. In contrast, none of the mice injected with LLC/FasL or LLC/FasL/GM‐CSF develop tumors. Specific memory immune response and delayed LLC‐1 tumor growth are found in mice immunized with LLC‐1/FasL or LLC‐1/FasL/GM‐CSF. Furthermore, therapeutic effects are observed only when LLC‐1/FasL/GM‐CSF tumor vaccine is employed to retard growth of preexisting LLC‐1 tumors. Tumor growth is also completely suppressed in mice injected with a mixture of LLC‐1 and LLC‐1/FasL/GM‐CSF. In addition, IL‐12 production, cytotoxic T‐cell activity and IgG against LLC‐1 are manifested in mice injected with LLC/FasL/GM‐CSF. Our data show that FasL‐induced pathway triggers expression of proinflammatory cytokines, including IL‐1β, IL‐6, MIP‐2 and MCP‐1, while GM‐CSF‐dependent pathway promotes functional maturation and activation of DCs. Taken together, the results indicate that dual gene‐based delivery with FasL and GM‐CSF may serve as a more effective tumor vaccine to suppress lung cancer cell growth in vivo. © 2008 Wiley‐Liss, Inc.

IL-27 Directly Restrains Lung Tumorigenicity by Suppressing Cyclooxygenase-2-Mediated Activities

“…After adding the LLC-1 target cells (10 4 /100 l) to different numbers of effector cells (100 l) in 96-well U-bottom plates, the plates were centrifuged at 250 ϫ g for 2 min and then cultured at 37°C in a 5% CO 2 incubator for 16 h. The plates were then centrifuged at room temperature and lactate dehydrogenase activity in the supernatants of each well was detected by the CytoTox 96 non-radioactive cytotoxicity assay kit (Promega) (31). The percentage of lysis was calculated as follows: percentage lysis ϭ (experimental release Ϫ spontaneous release)/(total release Ϫ spontaneous release) ϫ 100.…”

“…LLC-1 cells (2 ϫ 10 5 /100 l) were cultured in 96-well plates at 37°C for 16 -18 h and then fixed with methanol at room temperature for 10 min. Serum samples were diluted by 400-fold, and the measurement of serum IgG was followed by our established ELISA procedures (31).…”

An Exopolysaccharide from Cultivated Cordyceps sinensis and its Effects on Cytokine Expressions of Immunocytes

“…They are glycoproteins of low molecular weight and may also significantly affect the growth of tumors in vivo [12][13][14][15]. TNF-α is a multifunctional cytokine playing a key role in apoptosis and cell survival as well as in inflammation and immunity.…”

Influence of Berry Polyphenols on Receptor Signaling and Cell-Death Pathways: Implications for Breast Cancer Prevention

“…Saarinen et al ., treated rats with 3 or 15 mg/kg of LR ten weeks after mammary tumors were induced with DMBA. While there was no reduction in incidence or multiplicity of these already established tumors, LR significantly reduced tumor growth and surface area after 9 weeks of administration (83). Dietary LR (100 mg/kg) also reduces the growth of orthotopic MCF-7 tumors in nude mice (84) (85).…”