A matrix attachment region (MAR)-binding activity due to a p114 kilodalton protein is found only in human breast carcinomas and not in normal and benign breast disease tissues.
A M(r) 114,000 protein (p114) that specifically binds to nuclear matrix attachment DNA (matrix attachment region, MAR) from a breast carcinoma cell line SK-BR-3 was purified to near homogeneity. p114 strongly binds to a wild-type A+T-rich MAR probe with high unwinding propensity with a dissociation constant (Kd) of 10(-9), while it exhibits substantially reduced binding to a mutated A+T-rich non-MAR probe, which lacks unwinding propensity. This binding specificity and affinity is similar to the previously cloned thymocyte-associated MAR-binding protein SATB1. By Southwestern blot analysis, the MAR-binding activity of p114 is detectable in human breast carcinomas but is undetectable in normal breast tissues, benign breast diseases, and immortalized epithelial MCF-10A cells. Thus, the MAR-binding activity of p114 is not merely reflecting cell proliferation, but it strongly associates with breast carcinomas. The p114 MAR-binding activity was found in all 43 human breast carcinoma specimens tested, without exception. Much stronger p114 MAR-binding activity was detected in poorly differentiated than well-differentiated carcinomas. p114 may be a reliable diagnostic and possibly prognostic marker for breast cancer.
Yanagisawa
J
J
La Jolla Cancer Research Foundation, California 92037, USA.
Ando
J
J
Nakayama
J
J
Kohwi
Y
Y
Kohwi-Shigematsu
T
T
D001483:Base Sequence; D001665:Binding Sites; D014408:Biomarkers, Tumor / Q000302:isolation & purification / Q000378:metabolism*; D001940:Breast / Q000378:metabolism*; D001941:Breast Diseases / Q000378:metabolism*; D001943:Breast Neoplasms / Q000378:metabolism* / Q000473:pathology; D004247:DNA / Q000378:metabolism; D004273:DNA, Neoplasm / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000302:isolation & purification / Q000378:metabolism*; D005260:Female; D006801:Humans; D036961:Matrix Attachment Region Binding Proteins; D008969:Molecular Sequence Data; D009363:Neoplasm Proteins / Q000302:isolation & purification / Q000378:metabolism*; D014407:Tumor Cells, Cultured
C097879:114 kDa MAR-binding protein, human; D014408:Biomarkers, Tumor; D004273:DNA, Neoplasm; D004268:DNA-Binding Proteins; D036961:Matrix Attachment Region Binding Proteins; D009363:Neoplasm Proteins; D004247:DNA