Sirna oligonucleotides targeting

Plasmids pEnter-MMP1-Flag and pEnter-vector were obtained from Vigene Bioscience (Rockville, MD, USA). Short interfering RNA (siRNA) oligonucleotides targeting MMP1 were purchased from GenePharma (Shanghai China); the siRNA sequences are shown in Supplementary Table S1. Plasmid (2 μg) and siRNA oligonucleotide (100 nmol/L) transfections were carried out using Lipofectamine 3000 (Invitrogen) according to the manufacturer's instructions. The cells were used for further studies at 48 h after transfection.

siRNA oligonucleotides targeting CDH4, along with negative control siRNA, were procured from GenePharma (Shanghai, China). Lentiviral constructs that express the full-length CDH4 or shRNA sequences that targeted CDH4 were generated by cloning the corresponding sequences into the pCDH-CMV-MCS-EF1-Puro vector. The HA-Ub plasmid (pCMV-HA-Ub), His-CDH4 plasmid (pCMV-6 × His-CDH4), and Flag-β-catenin plasmid (pCDEF-FLAG-β-catenin) were obtained from Miaoling (Wuhan, China). Transfection techniques adhered to previously reported methods and manufacturer's instructions [18 (link)]. The specific sequences of the siRNA or shRNA mentioned above can be found in Additional file 1: Table S1.

RNA interference (siRNA) oligonucleotides targeting NEIL3 and negative control siRNAs were purchased from GenePharma (Shanghai, China). The siRNA sequences are listed in Supplementary Figure S1A. Transient siRNA transfection was carried out as described in a previous study^{24 (link)}. The NEIL3 sequence was cloned into the pLV-CMV-MCS-EF1-ZsGreen1-T2A-puro vector (Fenghui Biotechnology, Hunan, China) to construct the overexpression plasmid (Supplementary Figure S1B). Acquisition of lentivirus, packaging of lentivirus, and screening of stable cells were carried out as described in our previous study^{24 (link)}.