DNA dC->dU-editing enzyme APOBEC3B (APOBEC3B)

DNA dC->dU-editing enzyme APOBEC3B (Apolipoprotein B mRNA editing enzyme catalytic polypeptide-like 3B) is a member of the cytidine deaminase family that plays a dual role in human biology. Primarily, it functions as an innate immune factor, protecting the host against viral infections (such as HBV, HIV, and HPV) and retrotransposons by deaminating cytosine to uracil in single-stranded DNA, leading to hypermutation and inactivation of foreign genetic material [2, 3, 13]. However, its aberrant overexpression in various cancers, particularly breast, bladder, and lung, leads to off-target genomic mutations characterized by specific mutational signatures (SBS2 and SBS13) and clustered mutations known as kataegis [6, 12, 18]. This APOBEC-mediated mutagenesis drives tumor evolution, genetic heterogeneity, and the development of resistance to therapies like tamoxifen and immunotherapy [6, 12, 19]. Consequently, APOBEC3B is being investigated as a therapeutic target; inhibiting its enzymatic activity could potentially slow cancer progression and enhance the efficacy of existing treatments [6, 8, 23]. Notably, a common germline deletion of APOBEC3B in certain populations suggests that the enzyme is dispensable for normal health, making it an attractive target with potentially manageable safety profiles [10, 23].

Other names

A3BAPOBEC1LARCD3ARP4PHRBNLPhorbolin-1-related proteinPhorbolin-2/3bK150C2.2DJ742C19.2Apolipoprotein B mRNA editing enzyme catalytic subunit 3BApolipoprotein B mRNA editing enzyme catalytic polypeptide-like 3B

Cytidine deaminase inhibition