With the utilization of WB and FACS and also by qRT-PCR and GEP analyses for evaluating the FASN protein and transcript expression level in both sensitive-resistant trastuzumab HER2+ GC cell lines under 2D and 3D culture conditions and found the FASN expression level was higher in 3D cultures, which was in collaboration with high CSC characteristics and worse prognosis. Here, FASN is linked to gastric cancer.