Recombinant viruses can produce cytokines in tumors mobilizing an immune response to tumor cells. In this study, the authors investigated gene expression, in vivo antitumor efficacy, and safety of attenuated recombinant vaccinia virus (rVV) carrying murine cytokine genes interleukin (IL)-2 (rVV-mIL-2), IL-12 (rVV-mIL-12), and both IL-2 and IL-12 (rVV-2-12) in an athymic nude mice model. Significant tumor inhibition (p < 0.05) was observed in a preestablished subcutaneously implanted C6 glioma model using rVVs at doses ranging from 10(2) to 10(7) plaque forming units (PFU). An antitumor effect did not depend on the dose of the rVV-mIL-2 and rVV-mIL-12 viruses. All constructed rVVs induced a high level of cytokine expression in vitro and in vivo. Most groups injected with high doses of recombinant viruses encoding cytokine genes (10(5) to 10(7) PFU) showed signs of cytokine toxicity, whereas in the low-dose treatment groups (10(2) to 10(3) PFU) toxicity was greatly reduced. The antitumor activity of rVV-mIL-12 was associated with increases in both the percentage and number of natural killer T cells in the spleen. Local detection of interferon-y and tumor necrosis factor-alpha was also correlated with tumor growth arrest induced by the treatment. High-dose VV control vector per se induced tumor inhibition by activating Mac-1+ cells in blood, but the antitumor effect was less pronounced compared with rVV-carrying cytokine genes (p < 0.05). These results suggest that attenuated recombinant strains of VV at low doses may potentially be efficient vectors for cancer immunotherapy.

No abstract

Gastric and gastroesophageal adenocarcinoma (GGA) are significant worldwide health problems. With most patients presenting with advanced disease, palliative chemotherapy plays a significant role in treatment. Results from recent phase III studies of cytotoxic agents in combination therapy, such as docetaxel, oxaliplatin, irinotecan, capecitabine, and S-1, have been encouraging and provide patients with additional therapeutic options. Although these forthcoming regimens have allowed for more flexible patient-tailored therapy, survival continues to be suboptimal. Although still in its infancy, targeted biotherapy, including inhibitors of the vascular endothelial and epidermal growth factor receptors, seems to be promising and its incorporation into the next generation of clinical trials will hopefully improve outcomes and help advance future treatments. This article reviews current active chemotherapeutic regimens and explores the role of novel targeted therapies in advanced GGA.

No abstract