CENPB

CENPB Full Name

centromere protein B, 80kDa

CENPB Introduction

Introduction
The CENPB (centromere protein B) gene encodes one of the fundamental architectural proteins responsible for building and maintaining the centromere—the chromosomal region essential for accurate segregation during cell division. As the most abundant and highly conserved centromere component, CENPB serves as the primary DNA-binding protein that interacts directly with specific sequences in centromeric alpha satellite DNA. Beyond its structural role, this protein carries an extraordinary evolutionary legacy: it is derived from transposases of the ancient pogo DNA transposon family, representing a remarkable example of how mobile genetic elements have been domesticated to serve essential chromosome functions. CENPB is also clinically significant as the major autoantigen recognized by anti-centromere antibodies in patients with limited systemic scleroderma (CREST syndrome) and has recently emerged as a potential oncogenic factor and prognostic biomarker in multiple cancer types.

Figure 1. Strcuture of CENPB.

Role in Chromosome Segregation and Development
Studies in animal models have illuminated CENPB's physiological requirements. Cenpb null mice generated by targeted disruption appear grossly normal but exhibit reduced body weight and significantly reduced testis or uterine weight. Female knockout mice show age-dependent reproductive deterioration leading to complete breakdown by 9 months of age, with grossly disrupted luminal and glandular uterine epithelium despite normal myometrium and endometrium. High Cenpb expression in wildtype uterine epithelium suggests an essential role in maintaining epithelial integrity and reproductive function. Males also show reproductive organ abnormalities, though the precise mechanisms remain under investigation. In fission yeast, CENPB homologs perform genome surveillance functions, localizing to and recruiting histone deacetylases to silence Tf2 retrotransposons. These proteins repress solo long terminal repeats and LTR-associated genes, preventing retrotransposon mobilization and maintaining genome integrity. This ancestral function may be partially retained in human CENPB, though its primary role has shifted to centromere organization.

Emerging Role in Cancer Biology
Recent research has identified CENPB as a potential oncogenic factor and prognostic biomarker in multiple malignancies. In hepatocellular carcinoma (HCC), comprehensive analysis using TCGA and GEO datasets revealed significantly higher CENPB mRNA expression in tumor tissues compared to normal controls across three independent datasets. Immunohistochemical analysis of 490 HCC patients confirmed elevated CENPB protein levels, with expression increasing as pathological stage and histological grade advanced. Patients with elevated CENPB mRNA and protein demonstrated shorter overall survival and recurrence-free survival, and the protein showed prognostic value even in early-stage patients (stage I/II), those with AFP below 400 ng/ml, and tumors smaller than 5 cm. Functional studies demonstrated that knockdown of CENPB in HCC cell lines significantly inhibited cell proliferation and invasion, supporting an oncogenic role. Mechanistically, CENPB is directly regulated by miR-29a, a tumor-suppressive microRNA, as validated by dual-luciferase reporter assays.

Alternate Names for CENPB

CENPB; centromere protein B, 80kDa; centromere protein B (80kD); major centromere autoantigen B; CENP B; centromere autoantigen B; Centromere protein B; Major centromere autoantigen B; CENP-B; centromere autoantigen B