Angiogenin (ANG), a member of the RNase A superfamily, is a 14.4 kDa protein initially identified for its role in stimulating blood vessel formation (angiogenesis). Discovered in 1985. ANG is secreted under hypoxic or inflammatory conditions and binds to endothelial cells to promote neovascularization, a critical process in tumor growth and wound healing. Beyond angiogenesis, ANG exhibits ribonucleolytic activity, cleaving RNA to regulate stress response pathways. Notably, it processes transfer RNA (tRNA) into stress-induced tRNA-derived fragments (tiRNAs) during cellular stress, modulating translation and cell survival.
Dysregulation of ANG is implicated in cancer, neurodegenerative diseases (e.g., ALS), and inflammatory disorders. In cancer, elevated ANG levels correlate with tumor progression and metastasis. Conversely, ALS-linked ANG mutations impair its neuroprotective functions, disrupting RNA homeostasis and accelerating motor neuron degeneration.
ANG antibodies, developed for research and diagnostics, detect ANG expression in tissues or biological fluids, aiding studies on its pathological roles. Therapeutic strategies targeting ANG, including neutralizing antibodies, are under exploration to inhibit tumor angiogenesis or restore ANG function in neurodegenerative diseases. However, clinical applications remain limited, emphasizing the need for further research into ANG's complex biology and therapeutic potential.