Casitas B-lineage lymphoma-b

Cbl-b functions as an E3 ubiquitin ligase that regulates B-cell receptor (BCR) signaling and downstream activation of proliferative pathways in B lymphocytes^[1][2][4]. Mechanistically, Cbl-b modulates antigen-induced BCR internalization and controls the amplitude of NF-κB, PI3K/Akt, and MAPK pathway activation, thereby influencing B-cell survival and proliferation^[6][2][5]. In disease models, dysregulation of Cbl-b contributes to B-cell malignancies such as diffuse large B-cell lymphoma (DLBCL) and chronic lymphocytic leukemia (CLL), where altered ubiquitination leads to enhanced oncogenic signaling^[3][2][7]. Compared with related isoforms, Cbl-b exhibits distinct substrate specificity and regulatory roles, differing from Cbl and Cbl-c in modulating tonic versus antigen-dependent BCR signaling^[1][4][5]. Experimental inhibition of Cbl-b can enhance BCR signaling in vitro, whereas agonist-like modulation has been explored to restrain hyperactive B-cell proliferation, suggesting potential applications for dissecting lymphomagenesis mechanisms^[2][4][8]. Therefore, Cbl-b represents both a mechanistic node for B-cell activation and a practical target for studies of malignant B-cell regulation and therapy development^[1][2][7].