Definition

A humanized immunoglobulin G1 (IgG1) monoclonal antibody directed against gremlin-1 (gremlin1; GREM1; Drm), with potential antineoplastic activity. Upon administration, anti-gremlin-1 monoclonal antibody TST003 specifically targets and binds to gremlin-1, thereby neutralizing gremlin-1 expressed on tumor cells and cancer associated fibroblasts (CAFs). This prevents binding to bone morphogenetic proteins (BMP), specifically to BMP2 and 4, and blocks the gremlin-1-mediated inhibition of BMP signaling pathways. This may lead to increased infiltration of CD8 T-cells into the tumor and may inhibit tumor cell growth and proliferation. Gremlin-1, a BMP antagonist and a member of the tumor growth factor (TGF)-beta superfamily, is overexpressed in a variety of cancer cell types. It is involved in cancer cell growth and proliferation, and promotes epithelial to mesenchymal transition (EMT). Overexpression of gremlin-1 is often associated with poor prognosis.