Promotion of intestinal carcinogenesis by Streptococcus bovis
Promotion of intestinal carcinogenesis by Streptococcus bovis
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DOI：
10.1093/carcin/21.4.753
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发表时间：
2000-04-01
期刊：
影响因子：
4.7
通讯作者：
Raul, F
中科院分区：
文献类型：
--
作者：
Ellmerich, S;Schöller, M;Raul, F
牛链球菌是人类肠道植物群的一员，其与结直肠肿瘤性疾病的关系一直是一个有争议的问题。本研究的目的是确定牛链球菌和从细菌细胞壁中提取的抗原对肠道早期癌前病变的影响。成年大鼠接受氧化偶氮甲烷（15 mg/kg体重）的腹膜内注射，每周一次，持续2周。在最后一次注射致癌物后15天（第4周），大鼠在5周内每周两次通过管饲法接受牛链球菌（10（10）个细菌）或壁提取抗原（100 μ g）最后一次管饲后一周（第10周），我们发现，牛链球菌或该细菌抗原的给药通过增加肿瘤前病变的细胞增殖，促进肿瘤前病变的进展。结论牛链球菌可诱导大鼠结肠癌前病变的发生，促进结肠癌前病变的形成，促进结肠癌前病变的发生，促进结肠癌前病变的形成，促进结肠癌前病变的形成，促进结肠癌前病变的发生。事实上，细菌壁蛋白是比完整细菌更有效的肿瘤转化诱导剂，这可能在结肠癌预防中具有重要意义。
The involvement of Streptococcus bovis, an member of the human gut flora, in colorectal neoplastic diseases is an object of controversy. The aim of this study was to determine the effects of S.bovis and of antigens extracted from the bacterial cell wall on early preneoplastic changes in the intestinal tract. Adult rats received i.p, injections of azoxymethane (15 mg/kg body weight) once per week for 2 weeks. Fifteen days (week 4) after the last injection of the carcinogen, the rats received, by gavage twice per week during 5 weeks, either S.bovis (10(10) bacteria) or wall-extracted antigens (100 mu g) One week after the last gavage (week 10), we found that administration of either S.bovis or of antigens from this bacterium promoted the progression of preneoplastic lesions through the increased formation of hyperproliferative aberrant colonic crypts, enhanced the expression of proliferation markers and increased the production of IL-8 in the colonic mucosa, Our study suggests that S.bovis acts as a promoter of early preneoplastic lesions in the colon of rats. The fact that bacterial wall proteins are more potent inducers of neoplastic transformation than the intact bacteria may have important implications in colon cancer prevention.