CCCTC-binding factor-like protein (CTCFL) (CTCFL)

CCCTC-binding factor-like protein (CTCFL), commonly referred to as BORIS (Brother of the Regulator of Imprinted Sites), is a DNA-binding protein and a paralog of the essential chromatin insulator CTCF [UniProt]. Under physiological conditions, CTCFL expression is strictly limited to the germ cells of the testis, where it facilitates epigenetic reprogramming and chromatin remodeling during spermatogenesis [NCBI Gene]. However, CTCFL is frequently activated in a wide range of human cancers, including breast, lung, and ovarian malignancies, where it functions as an oncogene by altering the transcriptional landscape to favor tumor growth and survival [PubMed: 23536445].\n\nAs a cancer-testis antigen, its restricted normal expression makes it an attractive target for immunotherapy, with various strategies such as DNA vaccines and T-cell therapies currently under investigation [ClinicalTrials.gov]. Therapeutic targeting of CTCFL aims to induce a specific immune response against malignant cells while minimizing damage to healthy somatic tissues [PubMed: 28630053]. Additionally, its presence in the blood or tumor tissue of patients serves as a potential biomarker for cancer diagnosis and disease progression [PubMed: 20606245]. The protein contains 11 zinc-finger domains that are nearly identical to those of CTCF, allowing it to compete for similar DNA binding sites while exerting distinct regulatory effects [UniProt].

Other names

BORISBrother of the Regulator of Imprinted SitesCancer/testis antigen 27CT27Zinc finger protein CTCFL

Induction of cytotoxic T-lymphocyte (CTL) response against CTCFL-expressing tumor cells and disruption of oncogenic transcriptional programs.