While gC1qR promotes tumor cell survival by enhancing angiogenesis and metastasis and also by contributing to the hypercoagulable and prothrombotic microenvironment, cC1qR/CR expression represents a pro-phagocytic "eat-me" signal through which cC1qR/CR expressing tumor cells are tagged for destruction by macrophages.
Recent studies have proved beyond any doubt about the involvement of the ubiquitous, myriad ligand binding, multi-functional human protein, hyaluronan-binding protein 1 (HABP1), which is identical to the splicing factor associated protein (p32) and the receptor of the globular head of the complement component (gC1qR) in tumorigenesis and cancer metastasis.
Complement component 1, q subcomponent binding protein (C1QBP) can mediate growth factor-induced cancer cell chemotaxis and distant metastasis by activation of receptor tyrosine kinases.
Furthermore, C1QBP was observed to be overexpressed in breast cancer tissues, and its expression level was closely linked with distant metastasis and TNM stages.
Hyaluronic acid binding protein 1 (HABP1/gC1qR/p32), a ubiquitous multifunctional protein belonging to the hyaladherin family, has been implicated in the tumorigenesis, progression, invasion, and metastasis of several malignant tumors.
HABP1 might be an independent predictive factor for breast cancer prognosis and up-regulation of HABP1 might play an important role in the metastasis of breast cancer.