PA (purity 97% by HPLC) was obtained from Shanghai Yuanye Biotechnology Co., Ltd., China. PA was dissolved in dimethyl sulfoxide (DMSO) at a concentration of 10 mM and stored at − 20 °C. SGC-7901 cell-specific culture medium; phosphate-buffered saline (PBS); trypsin; Fetal Bovine Serum (FBS); Transwell permeable supports, 8.0 μm polycarbonate membrane; MTT; E-cadherin, N-cadherin, vimentin, and β-actin antibodies; TIMP-1; anti-rabbit IgG, HRP-conjugated antibody were purchased from Thermo.

The human gastric cancer cell line SGC-7901 and Human Gastric mucosal Epithelial Cells GES1 was obtained from China Procell Life Science & Technology Co., Ltd. (Catalog number: CL-0021). The cells were cultured in SGC-7901 cell-specific culture medium at 37 °C and monitored for growth status over time in an incubator with 5% CO2. When the cell confluence exceeded 80%, the cells were dissociated using trypsin, and passaged every 2 to 3 days.

SGC-7901 and GES1 cells in the logarithmic growth phase were suspended as single cells after trypsin digestion and seeded at a density of 3 × 103 cells per well in a 96-well plate. Subsequently, the cells were treated with PA at final concentrations of 0, 25, 50, 100 and 500 μM. Following a 24-h incubation period in a CO2 incubator, 10 μL of 5% MTT solution was added to each well, and the plate was further incubated for 4 h. After discarding the supernatant, 100 μL of DMSO was added to each well. Absorbance values at 490 nm were measured for each well using an automatic microplate reader.

SGC-7901 cells in the logarithmic growth phase were digested with trypsin and seeded at a density of 3 × 106 cells per well in 6-well plates. Cultured at 37 °C in a CO2 incubator, when cellular confluence exceeded 80%, a scratch was made on the monolayer using the tip of a 200 μL pipette, followed by PBS washing to remove debris. Subsequently, cells were treated with PA at concentrations of 0, 50, and 100 μM, and incubated further. Images of the scratch area were captured at 0 and 24 h using an inverted microscope, and scratch width was quantified using ImageJ software.

Matrigel was diluted eightfold in serum-free culture medium and added to Transwell chambers, which were then incubated at 37 °C for 4 h for gel solidification. SGC-7901 cells in the logarithmic growth phase, suspended after trypsin digestion, were seeded at a density of 2 × 104 cells per well in the upper chamber and treated with PA at concentrations of 0, 50, and 100 μM in the lower chamber. Following 24 h of culture, cells were washed with PBS, fixed in methanol, and stained with crystal violet. The number of migrated cells was counted in 5 randomly selected areas per well using an inverted microscope. The remaining steps were consistent with the Transwell invasion assay.

After SGC-7901 cells treated with specified concentrations of PA for 48 h, cells were fixed with 4% paraformaldehyde. After incubation with 0.1% Triton X-100 for 30 min, cells were blocked with 1% FBS and then incubated with primary antibodies at 4 °C for 12 h. Then, cells were incubated with secondary antibodies for 2 h. Cell nuclei were stained with DAPI for 10 min. Mitochondria and cell nuclei were visualized under a fluorescence microscope, and signal intensity was quantified using ImageJ software.

Total RNA was extracted using Trizol (Invitrogen, USA) according to the manufacturer’s instructions. cDNA was synthesized using the Prime-Script RT reagent kit from Thermo Fisher (USA). Quantitative polymerase chain reaction (qPCR) was performed using the SYBR Green PCR kit (QIAGEN, Dusseldorf, Germany) to determine gene expression levels. β-Actin was used as an internal control. The relative mRNA levels of target genes were normalized to β-actin using the 2−ΔΔCT method.

Proteins in equal volumes were electrophoresed on SDS-PAGE gels before being transferred to NC membranes. After blocking with 5% skim milk in Tris-buffered saline, the membranes were incubated with the corresponding primary antibodies overnight at 4 °C, followed by an additional 2-h incubation at room temperature on a rotating shaker. Signals were developed using ECL (GE, USA). The grayscale values of the bands were analyzed using image analysis software (Image J), and protein bands were imaged using a gel analysis system.

All animal experiments were approved by the Animal Ethics Committee and conducted following the Guide for the Care and Use of Laboratory Animals from the National Institutes of Health. Five-week-old female BALB/C nude mice (18–20 g) were obtained from Shanghai SLAC Laboratory Animal Co., Ltd., China. Prior to tumor establishment, SGC-7901 cells were treated with specified concentrations of PA for 48 h. Euthanasia was performed on animals, and tumors were excised and weighed on day 90 post-implantation for tumor size analysis.

All data were obtained from at least three independent experiments. Graph Prism 8.0 software was used for one-way analysis of variance (ANOVA) to determine statistical significance. *P < 0.001 was considered statistically significant.