PXN and breast cancer: Figure 5A presents the sites of protein phosphorylation on PXN. After a series of analyses, we observed that four types of tumor (colon cancer, RCC, UCEC, and ovarian cancer) exhibit a lower phosphorylation level in all primary tumor tissues compared with normal tissues at the S258 locus within the PXN domain (P < 0.001). Lower protein phosphorylation of PXN was noted in colon cancer, UCEC, and breast cancer at the S137 locus within the PXN domain (P < 0.001), followed by a decreased phosphorylation level of the S303 locus for colon cancer, UCEC, and ovarian cancer (P < 0.001) (Figure 5B–5G).