Interleukin-6 produced by pancreatic carcinoma cells enhances humoral immune responses against tumor cells: A possible event in tumor regression
✍ Scribed by Katsunori Saito; Hiroshi Ishikura; Takashi Kishimoto; You Kawarada; Tomoyuki Yano; Toshiyuki Takahashi; Hiroyuki Kato; Takashi Yoshiki
- Publisher
- John Wiley and Sons
- Year
- 1998
- Tongue
- French
- Weight
- 119 KB
- Volume
- 75
- Category
- Article
- ISSN
- 0020-7136
No coin nor oath required. For personal study only.
✦ Synopsis
Production of interleukin-6 (IL-6) by human pancreatic carcinoma cells inversely correlates with potentials for bloodborne metastasis to the liver in nude mice. IL-6 cDNA was transfected to PCI-43, one of our cultured pancreatic carcinoma cell lines that does not produce IL-6 and generates numerous metastases to the liver. An IL-6 high-producer clone (PCI-43h) generated few metastases; IL-6 production thus has a direct effect on metastasis, whereas other transfectants (PCI-43I and PCI-43n), which are IL-6 low-, and IL-6 non-producers, respectively, did generate metastases. Tumorreactive IgG, which mediated antibody-dependent cellular cytotoxicity (ADCC) in vitro, was detected in sera from recipient nude mice inoculated with PCI-43h but not in sera from mice given PCI-43I, PCI-43n or parent PCI-43. Tumorreactive IgM was detected in sera from all mice, irrespective of inoculated PCI-43 species, with a slight augmentation being noted in PCI-43h-inoculated nude mice. Severe combined immunodeficiency (SCID) beige mice were then used as recipients for PCI-43 species, and tumorigeneity was examined by s.c. inoculation of a suboptimal number of PCI-43 transfectants (1 ؋ 10 6 /0.1 ml). Only PCI-43h formed palpable masses in SCID beige mice, whereas it first grew to be palpable but subsequently became not palpable in nude mice, thereby revealing a dual action of tumor-derived IL-6. Thus, tumor-derived IL-6 confers growth promotion in SCID beige mice, while the same cytokine exhibits anti-tumorigenic functions, presumably through humoral immune responses, in nude mice. Int.