Systemic inflammation enhances metastatic growth in a syngeneic neuroblastoma mouse model

Abstract

Background We previously showed that total tumor resection enhances metastatic growth in a syngeneic metastatic mouse model of neuroblastoma. In this study, we further investigated which surgical factors contributed most to metastatic growth. Methods Tumor cells derived from MYCN transgenic mice were subcutaneously injected into wild-type mice. Mice were randomly assigned to receive partial resection (PR group), subcutaneous implantation of a sponge (Sp group), or observation (Obs group). The lymph node metastasis volume and frequency of lung metastasis were compared 14 days after assignment by measuring C-reactive protein (CRP) and interleukin-6 (IL-6) levels. Results The lymph node metastasis volume in the Sp group was larger than in the Obs group (148.4 [standard deviation {SD}: 209.5] vs. 10.2 [SD 12.8] mm³). The frequency of lung metastasis was greater in the Sp group than in the PR group (11.9 [SD 12.2] vs. 6.6 [SD 4.0] counts/slide). The CRP level in the Sp group was higher than in the PR group (2.3 [SD 0.5] vs. 1.5 [SD 0.4] µg/mL), and the IL-6 level in the Sp group was higher than in the PR or Obs groups (28.4 [SD 34.5] vs. 12.4 [SD 19.0] vs. 5.4 [SD 8.1] pg/mL). Conclusion Metastatic growth may be enhanced by systemic inflammation.