Among extracellular matrix organization proteins, SPARC, COL1A1, FN1 and LAMC1 had a high expression, cell experiments showed LAMC1 was highly expressed in all gastric cancer cell lines (Figure S1A), and mass spectrometry results indicated that the expression of peritoneal metastases was 1.59 times higher than that in primary foci (Fig. 1D). This evidence concerns the gene COL1A1 and gastric cancer.