NLE1在结肠癌中的表达及其对HT29细胞增殖凋亡的影响

目的 验证Notchless同源物1(Notchless homolog 1,NLE1)在结肠腺瘤及腺癌组织中的表达水平,评价其可能作用及机制。方法 通过免疫组化及实时荧光定量聚合酶链式反应(polymerase chain reaction,PCR)方法评价NLE1在结肠正常黏膜、腺瘤组织及腺癌组织中的表达水平。通过慢病毒转染,评价NLE1沉默对HT29细胞增殖、凋亡的影响及可能机制。结果 免疫组织化学(immunohistochemistry,IHC)染色显示,NLE1在结肠正常黏膜、腺瘤及腺癌组织中的高表达率分别为14.3% (15/105),44.0% (11/25)及68.6% (72/105),在腺癌中明显高于腺瘤(P<0.05),在腺瘤中明显高于正常黏膜(P<0.001)。实时荧光定量PCR显示,结肠正常黏膜、腺瘤及腺癌组织三组的NLE1 mRNA表达分别为1.38±0.82,5.04±2.09,7.57±1.25。腺癌组织中NLE1表达水平明显高于腺瘤(P<0.05),腺瘤组织中明显高于正常黏膜(P<0.01)。NLE1沉默显著抑制HT29细胞增殖(P<0.05)及克隆形成能力(P<0.05),促进其凋亡(P<0.05),并可促进Bax及Fas的表达。结论 结肠腺癌中高表达的NLE1可能通过影响肿瘤细胞增殖凋亡从而发挥促进肿瘤发生的作用。

The expression of NLE1 in colon cancer and its influence on proliferation and apoptosis of HT29 cells

Objective s To verify the expression of Notchless homolog 1 (NLE1) in colon adenocarcinoma and evaluate its possible role and mechanism. Methods The expression of NLE1 was evaluated by immunohistochemistry (IHC) staining and quantitative polymerase chain reaction (PCR). Lentivirus transfection was used to explore the influence of NLE1 on proliferation and apoptosis of HT29 and possible mechanism. Results According to IHC, the high expression rate of NLE1 in normal mucosa, colon adenoma and early stage colon cancer was 14.3% (15/105),44.0% (11/25)and 68.6% (72/105),respectively. The expression of NLE1 was significantly higher in cancer compared with adenoma (P<0.05), as well as in adenoma compared with normal mucosa(P<0.001). According to quantitative RT-PCR, NLE1 expression in normal mucosa, colon adenoma and early stage colon cancer was 1.38±0.82,5.04±2.09, 7.57±1.25, respectively. The expression of NLE1 was significantly higher in cancer compared with adenoma (P<0.05), as well as in adenoma compared with normal mucosa(P<0.01). NLE1 silencing significantly inhibited proliferation and colony-forming ability and prmoted apoptosis of HT29 cells(all P<0.05), and increased the expression of Bax and Fas. Conclusions The elevated expression of NLE1 in colon adenoma and adenocarcinoma might promote colorectal carcinogenesis via promoting proliferation of tumor cells.