Previous studies showed that glyphosate stimulates breast cancer cell growth via estrogen receptors. The present study investigated the effect of glyphosate on the estrogen signaling pathway involved in the induction of cholangiocarcinoma (CCA) cell growth. HuCCA-1, RMCCA-1 and MMNK-1 were chosen for comparison. The effects of glyphosate on cell growth, cell cycle and molecular signaling pathways were measured. The results showed that HuCCA-1 cells expressed estrogen receptor alpha (ERα), while ERα was not detected in RMCCA-1 and MMNK-1 cells. ERα was mostly expressed in cytoplasmic compartment of HuCCA-1 cells. Estradiol (E2) (10⁻¹¹-10⁻⁵ M) induced cell proliferation in HuCCA-1 but not in RMCCA-1 and MMNK-1 cells. Glyphosate at the same concentration range also induced HuCCA-1 cell proliferation. The S phase of the cell cycle, and protein levels of the cyclin family were significantly increased after treatment of glyphosate or E2. Both compounds also induced the expression of proliferative signaling–related proteins including ERα, VEGFR2, pERK, PI3K(p85), and PCNA. These effects of glyphosate and E2 were abolished by the ER antagonist, 4-hydroxytamoxifen and U0126, a MEK inhibitor. The data from this study indicate that glyphosate can induce cell growth in ERα positive CCA cells through non-genomic estrogen receptor/ERK1/2 signaling pathway.

先前的研究表明，草甘膦通过雌激素受体刺激乳腺癌细胞的生长。本研究调查了草甘膦对参与诱导胆管癌（CCA）细胞生长的雌激素信号通路的影响。选择HuCCA-1，RMCCA-1和MMNK-1进行比较。测定了草甘膦对细胞生长，细胞周期和分子信号通路的影响。结果显示，HuCCA-1细胞表达雌激素受体α（ERα），而RMCCA-1和MMNK-1细胞中未检测到ERα。ERα主要在HuCCA-1细胞的细胞质区中表达。雌二醇（E2）（10 ^-11 -10 ^-5 M）诱导HuCCA-1中的细胞增殖，但不诱导RMCCA-1和MMNK-1细胞中的细胞增殖。在相同浓度范围内的草甘膦也诱导HuCCA-1细胞增殖。处理草甘膦或E2后，细胞周期的S期和细胞周期蛋白家族的蛋白质水平显着增加。两种化合物还诱导了与增殖信号相关的蛋白的表达，包括ERα，VEGFR2，pERK，PI3K（p85）和PCNA。草甘膦和E2的这些作用被ER拮抗剂4-羟基他莫昔芬和MEK抑制剂U0126消除了。这项研究的数据表明，草甘膦可以通过非基因组雌激素受体/ ERK1 / 2信号传导途径诱导ERα阳性CCA细胞中的细胞生长。