The analysis showed that Sdc-1 and HA and the proteins related to them were associated with “the role of PGs in breast cancer biology and translational medicine”, “Heparan sulphate and the art of cell regulation”, “Exploiting Heparan Sulfate Proteoglycans in Human Neurogenesis-Controlling Lineage Specification and Fate”, “Syndecans as modulators and potential pharmacological targets in cancer progression”, and “Proteoglycans in cancer biology, tumor microenvironment, and angiogenesis”, to cite some references (Table S2). Here, SDC1 is linked to breast cancer.