Department of Pharmacology and Toxicology, Rottapharm, Monza, Italy.
Cancer Chemother Pharmacol. 2010 Oct;66(5):819-27. doi: 10.1007/s00280-009-1224-1. Epub 2009 Dec 30.
Gastrointestinal mucositis, commonly associated with diarrhea, is a dose-limiting toxicity of chemotherapy. The new benzamidine derivative CR3294 reduces tissue damage in animal models of intestinal inflammation. Thus, we tested whether CR3294 had the potential to prevent chemotherapy-induced mucositis.
In tests on isolated cells, reactive oxygen species (ROS) formation and cytokine release were measured by chemiluminescence and immunoassays, respectively. In studies in vivo, BDF1 mice were given oral CR3294 (2.5-20 mg/kg) for 3 days before receiving 5-fluorouracil. Intestinal crypt survival, cell apoptosis and proliferation, and diarrhea score were assessed. Additionally, nude mice bearing tumor xenografts were treated with CR3294 and/or 5-fluorouracil, and tumor growth was monitored.
CR3294 significantly inhibited cytokine release from stimulated leukocytes at concentrations similar to the IC(50) (2.9 +/- 0.2 muM) for ROS production by these cells. Consistent with these molecular findings, CR3294 dose-dependently protected the intestinal mucosa against 5-fluorouracil-induced toxicity in a mouse model of mucositis. The number of surviving crypts per cross-section in mice receiving 20 mg/kg CR3294 was 2.8-fold that in vehicle-treated animals (18.1 +/- 1.9 vs. 6.5 +/- 0.9, P < 0.001). Moreover, CR3294 decreased the cumulative diarrhea score by 50%, reduced by nearly 70% the incidence of severe episodes, and increased by 3-fold the number of mice without diarrhea. CR3294 neither affected the growth of tumor xenografts nor protected tumors from the cytotoxic activity of 5-fluorouracil.
This study demonstrates that CR3294 acts on key molecular targets to reduce the signs of mucositis and the occurrence of diarrhea in mice exposed to the chemotherapy drug 5-fluorouracil.
胃肠道粘膜炎，通常伴有腹泻，是化疗的剂量限制毒性。新型苯甲脒衍生物 CR3294 可减少动物模型中肠道炎症的组织损伤。因此，我们测试了 CR3294 是否具有预防化疗引起的粘膜炎的潜力。
在分离细胞的测试中，通过化学发光和免疫测定分别测量活性氧（ROS）的形成和细胞因子的释放。在体内研究中，BDF1 小鼠在接受 5-氟尿嘧啶前连续 3 天给予口服 CR3294（2.5-20mg/kg）。评估肠隐窝存活率、细胞凋亡和增殖以及腹泻评分。此外，用 CR3294 和/或 5-氟尿嘧啶处理携带肿瘤异种移植物的裸鼠，并监测肿瘤生长。
CR3294 以与细胞产生 ROS 的 IC50（2.9 +/- 0.2 muM）相似的浓度显著抑制刺激的白细胞中的细胞因子释放。与这些分子发现一致，CR3294 剂量依赖性地保护了小鼠粘膜炎模型中的肠粘膜免受 5-氟尿嘧啶引起的毒性。接受 20mg/kg CR3294 的小鼠中每个横截面上存活的隐窝数量是接受载体处理的动物的 2.8 倍（18.1 +/- 1.9 vs. 6.5 +/- 0.9，P < 0.001）。此外，CR3294 使累积腹泻评分降低了 50％，使严重发作的发生率降低了近 70％，并使无腹泻的小鼠数量增加了 3 倍。CR3294 既不影响肿瘤异种移植物的生长，也不能保护肿瘤免受 5-氟尿嘧啶的细胞毒性作用。
本研究表明，CR3294 通过作用于关键的分子靶标来减少接受化疗药物 5-氟尿嘧啶的小鼠的粘膜炎迹象和腹泻的发生。
