NEU1 and cancer: In addition, we also conducted a regression analysis to fit the cancer type-specific metastasis rate against the sialic acid synthesis rate and the expression of the sialic acid degradation gene NEU1, giving rise to the following relationship:(11)Metastasisrate=1.91×sialicacidsynthesis-0.039×NEU1with P values of 0.071 and 0.076 for the two contributors, respectively.