Objective: 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.