Microbiology Research Department, Faculty of Medicine, University Putra Malaysia, 43400, UPM, Serdang, Selangor Darul Ehsan, Malaysia.
BMC Cancer. 2009 Nov 19;9:403. doi: 10.1186/1471-2407-9-403.
The seroprevalence of IgG antibodies of Streptococcus gallolyticus subspecies gallolyticus, CIP 105428, was evaluated to investigate the controversial association of S. gallolyticus with colorectal carcinoma and adenoma in attempt to investigate the nature of such association if any, by exploring the mRNA expression of NF-kappaB and IL-8. Moreover, the serological behavior of S. gallolyticus IgG antibodies was compared to that of an indicator bacterium of bowel, Bacteroides fragilis.
ELISA was used to measure IgG antibodies of S. gallolyticus and B. fragilis in sera of 50 colorectal cancer, 14 colorectal adenoma patients, 30 age- and sex- matched apparently healthy volunteers (HV) and 30 age- and sex- matched colonoscopically-proven tumor-free control subjects. NF-kappaB and IL-8 mRNA expression was evaluated in tumorous and non-tumorous tissue sections of carcinoma and adenoma patients in comparison with that of control subjects by using in situ hybridization assay.
Colorectal cancer and adenoma patients were associated with higher levels of serum S. gallolyticus IgG antibodies in comparison with HV and control subjects (P < 0.05) while no similar association was found with serum IgG antibodies of B. fragilis (P > 0.05). ELISA cutoff value for the seropositivity of S. gallolyticus IgG was calculated from tumor-free control group. The expression of NF-kappaB mRNA was higher in tumorous than non-tumorous tissue sections of adenoma and carcinoma, higher in carcinoma/adenoma sections than in control subjects, higher in tumorous sections of carcinoma than in adenoma patients, and higher in S. gallolyticus IgG seropositive than in seronegative groups in both tumorous and non-tumorous sections (P < 0.05). IL-8 mRNA expression in tumorous sections of adenoma and carcinoma was higher than in non-tumorous sections, higher in carcinoma/adenoma than in control subjects, and higher in S. gallolyticus IgG seropositive than in seronegative groups in tumorous rather than non-tumorous sections (P < 0.05).
S. gallolyticus most likely plays an essential role in the oncogenic progression of normal colorectal mucosa to adenoma and to CRC. This promoting/propagating role of S. gallolyticus might take place by utilizing certain inflammatory, anti-apoptotic, and angiogenic factors of transformation including NF-kappaB and IL-8.
为了探究链球菌种酿脓链球菌 CIP 105428 的 IgG 抗体的血清阳性率，评估其与结直肠癌和腺瘤之间存在的争议性关联，旨在通过探索 NF-κB 和 IL-8 的 mRNA 表达，调查如果存在任何关联，这种关联的本质。此外，将酿脓链球菌 IgG 抗体的血清学行为与肠道指示菌脆弱拟杆菌进行比较。
采用 ELISA 法测量 50 例结直肠癌患者、14 例结直肠腺瘤患者、30 例年龄和性别匹配的健康志愿者（HV）和 30 例年龄和性别匹配的结肠镜证实无肿瘤对照者血清中的酿脓链球菌和脆弱拟杆菌 IgG 抗体。通过原位杂交法，在结直肠癌和腺瘤患者的肿瘤和非肿瘤组织切片中评估 NF-κB 和 IL-8 mRNA 的表达，并与对照组进行比较。
与 HV 和对照组相比，结直肠癌和腺瘤患者的血清酿脓链球菌 IgG 抗体水平更高（P<0.05），而与血清脆弱拟杆菌 IgG 抗体无类似关联（P>0.05）。ELISA 检测酿脓链球菌 IgG 抗体的阳性切割值是从无肿瘤对照组计算得出的。NF-κB mRNA 在腺瘤和癌组织的肿瘤组织切片中的表达高于非肿瘤组织切片，在癌/腺瘤组织切片中的表达高于对照组，在癌组织切片中的表达高于腺瘤患者，在血清酿脓链球菌 IgG 阳性组中的表达高于血清阴性组，在肿瘤和非肿瘤组织切片中均如此（P<0.05）。IL-8 mRNA 在腺瘤和癌组织的肿瘤组织切片中的表达高于非肿瘤组织切片，在癌/腺瘤组织切片中的表达高于对照组，在血清酿脓链球菌 IgG 阳性组中的表达高于血清阴性组，主要在肿瘤组织切片中而非非肿瘤组织切片中如此（P<0.05）。
酿脓链球菌可能在正常结直肠黏膜向腺瘤和 CRC 癌变的致癌进展中发挥重要作用。酿脓链球菌的这种促进/传播作用可能通过利用 NF-κB 和 IL-8 等某些炎症、抗凋亡和血管生成因子的转化来发生。
