摘要目的：探讨S100钙离子结合蛋白A14（ S100A14）在乳腺癌组织中的表达以及表皮生长因子（ EGF）与S100A14的反馈调节机制。方法实时定量PCR检测51例乳腺癌组织和正常乳腺组织中S100A14 mRNA的表达以及EGF刺激或细胞外信号调节激酶（ p?ERK）抑制剂后细胞中S100A14 mRNA的表达。 Western blot 检测21例乳腺癌组织和正常乳腺组织中 S100A14蛋白的表达以及p?ERK抑制剂处理后细胞中S100A14蛋白的表达。 siRNA敲降S100A14后，采用Western blot检测细胞中S100A14、p?ERK和总ERK的表达。结果 S100A14 mRNA和蛋白在21例乳腺癌组织中的表达均升高（均P＜0．05）。 S100A14 mRNA高表达组乳腺癌患者的复发率高于 S100A14低表达组（P＝0．038）。 MDA?MB?453细胞中，1 ng／ml EGF组和10 ng／ml EGF组S100A14 mRNA相对表达水平分别为1．50±0．11和1．40±0．03，与对照组（1．00±0．09）比较，差异均有统计学意义（均P＜0．05）。 MCF?7细胞中，1 ng／ml EGF组和10 ng／ml EGF组S100A14 mRNA相对表达水平分别为1．66±0．08和1．71±0．17，与对照组（1．00±0．03）比较，差异均有统计学意义（均P＜0．05）。 TD47细胞中，1 ng／ml EGF组和10 ng／ml EGF＋U0126组S100A14 mRNA相对表达水平分别为1．56±0．04和1．00±0．10，与对照组（1．00±0．04）比较，差异均有统计学意义（均 P＜0．05）。敲降 S100A14能降低细胞 p?ERK 水平。过表达S100A14能够促进S100A14分泌。结论 EGF通过p?ERK信号通路促进S100A14 mRNA和蛋白的表达，EGF与S100A14之间可能存在反馈循环。

abstractsObjective To explore the expression of S100A14 in breast cancer tissue, and the EGF and S100A14 feedback regulatory mechanism. Methods S100A14 mRNA level in 52 cases of of breast cancer and adjacent normal tissue was detected by quantitative real?time PCR. S100A14 protein in 21 cases of breast cancer and adjacent normal tissue was detected by Western blot. S100A14 mRNA after EGF treatment was detected by RT?PCR and real?time PCR. The levels of S100A14, p?ERK and t?ERK were detected by Western blot. Knocking down S100A14 expression was performed by siRNA technology. Results The levels of S100A14 mRNA and protein were significantly increased in breast cancer tissues ( P<0.05 for both) . The high expression of S100A14 was related with the recurrence of breast cancer patients ( P=0.038). S100A14 mRNA level was significantly up?regulated in the MDA?MB?453 cells (1.50±0.11) and MCF?7 cells (1.40±0.03) after 1 ng/mL EGF treatment, and 1.66±0.08 and 1.71±0.17 in the MDA?MB?453 cells after 10 ng/mL EGF treatment, significantly higher than that of the control group (1.00±0.09 and 1.00±0.03) (P<0.05 for both). In the TD47 cells, the S100A14 mRNA levels in the control, 1 ng/ml EGF and 10 ng/ml EGF + U0126 treatment groups were 1. 00 ± 0. 04, 1. 56 ± 0. 04 and 1. 00 ± 0. 10, respectively ( P<0.05) . Conclusions The expression of S100A14 mRNA and protein is promoted by EGF through p? ERK signaling pathway in breast cancer cells. There may be a feedback loop between EGF and S100A14.