Leung Lawrence L, Myles Timothy, Morser John
Division of Hematology, Stanford University School of Medicine, Stanford, CA 94305, USA.
Veterans Affairs Palo Alto Health Care System, 3801 Miranda Avenue, Palo Alto, CA 94304, USA.
Cancers (Basel). 2023 Jul 3;15(13):3480. doi: 10.3390/cancers15133480.
Osteopontin (OPN) is a multi-functional protein that is involved in various cellular processes such as cell adhesion, migration, and signaling. There is a single conserved thrombin cleavage site in OPN that, when cleaved, yields two fragments with different properties from full-length OPN. In cancer, OPN has tumor-promoting activity and plays a role in tumor growth and metastasis. High levels of OPN expression in cancer cells and tumor tissue are found in various types of cancer, including breast, lung, prostate, ovarian, colorectal, and pancreatic cancer, and are associated with poor prognosis and decreased survival rates. OPN promotes tumor progression and invasion by stimulating cell proliferation and angiogenesis and also facilitates the metastasis of cancer cells to other parts of the body by promoting cell adhesion and migration. Furthermore, OPN contributes to immune evasion by inhibiting the activity of immune cells. Thrombin cleavage of OPN initiates OPN's tumor-promoting activity, and thrombin cleavage fragments of OPN down-regulate the host immune anti-tumor response.
骨桥蛋白（OPN）是一种多功能蛋白质，参与细胞黏附、迁移和信号传导等多种细胞过程。OPN中有一个单一的保守凝血酶切割位点，切割后会产生两个与全长OPN性质不同的片段。在癌症中，OPN具有促肿瘤活性，在肿瘤生长和转移中发挥作用。在包括乳腺癌、肺癌、前列腺癌、卵巢癌、结直肠癌和胰腺癌在内的各种癌症中，癌细胞和肿瘤组织中OPN表达水平较高，且与预后不良和生存率降低相关。OPN通过刺激细胞增殖和血管生成促进肿瘤进展和侵袭，还通过促进细胞黏附和迁移促进癌细胞向身体其他部位转移。此外，OPN通过抑制免疫细胞的活性促进免疫逃逸。OPN的凝血酶切割启动了OPN的促肿瘤活性，OPN的凝血酶切割片段下调宿主免疫抗肿瘤反应。
