Lymphocyte cytosolic protein 1 (LCP1)

Lymphocyte cytosolic protein 1 (LCP1), also known as Plastin-2 or L-plastin, is an actin-binding protein of the plastin family. It is specifically expressed in hematopoietic cell lineages and functions by crosslinking F-actin filaments, which stabilizes cytoskeletal structures and enables activation and migration of lymphocytes. Although normally restricted to immune cells, it is often aberrantly expressed in solid tumors—a phenomenon linked to cancer progression and migratory behavior. LCP1 is critical for T- and B-cell biology, serving as a scaffold for diverse signaling networks, including cytokine signaling (IL2RA/CD25, CD69), and its activation can be modulated by kinases such as PKC, BTK, and PI3K. Pharmacological inhibition of B-cell receptor pathways downregulates LCP1 activation and disrupts leukemia and lymphoma cell migration, establishing it as a key and targetable protein in cancer immunopathology and therapy. Serum anti-LCP1 IgG is useful as a biomarker for CLL patient stratification and monitoring.

Other names

LPLCP64PLS2LC64PHEL-S-37L-PLASTINplastin-2L-plastinepididymis secretory protein Li 37

Inhibition of B-cell receptor signaling (blocking phosphorylation/activation of LCP1 downstream of BCR); Disruption of actin bundling and lymphocyte/cancer cell migration (mechanistically via BTK or PI3K pathway inhibition)