Si foxc1

A FOXC1-specific siRNA (si-FOXC1) and its non-specific scramble siRNA (si-NC) were purchased from Stanta Cruz (Santa Cruz Biotechnology, USA), and transfections were carried out with Lipofectamine 2000 according to manufacturer’s recommended protocol. Briefly, Capan-2 and PANC-1 cells were transfected with either si-FOXC1 (100 nM) or si-NC (100 nM) for 48 h, followed by examination of cell proliferation. The efficiency of the siRNA on knocking down FOXC1 expression was examined by qRT-PCR 48 h after transfection.

The miR-138-5p mimics, miR-138-5p inhibitor, and the siRNA targeting FOXC1 (siFOXC1) were obtained from Santa Cruz Biotechnology (Santa Cruz, CA, USA). A549 cells (2 × 10⁵) were plated in 6-well plates and cultured for 24 h. The cells were then transfected with different RNAs using Lipofectamine 2000. After 48 h, the levels of target proteins were confirmed by Western blot, and the cells were subsequently used for further experiments. The levels of overexpression or inhibition of miR-138 were evaluated by qRT-PCR. The levels of inhibition of FOXC1 expression were determined by Western blot. **P < 0.01 compared to corresponding control groups (Additional file 2: Figure S1).