Fig. 2

HER2 expression was up-regulated by GEM treatment in some PDA cell lines. a Five PDA cell lines were either untreated or treated with GEM for 2 h, washed with PBS and incubated for another 48 h in fresh medium. HER2 expression was analyzed by flow cytometry. HER2 expression (ΔMFI) was calculated as the MFI of HER2 minus that of an isotype control. *P < 0.01 (n = 3) vs. untreated samples. b GEM-treated MIA PaCa-2 cells (0, 30, 100 and 300 ng/ml, 2 h) were incubated for 48 h, and the expression of the HER2 protein in the whole-cell lysates was analyzed using immunoblots. GAPDH was used as an internal control. c GEM-treated MIA PaCa-2 cells (0, 100, 300 and 1000 ng/ml, 2 h) were incubated for 2, 6, 12, 24 and 48 h, and the HER2 mRNA level in each treated cell line was determined using qRT-PCR. The HER2 mRNA expression levels were normalized to that of 18S ribosomal RNA and quantified using the ΔΔCt method. The level of HER2 mRNA at 6 h after GEM treatment is shown as a representative