The disappearing Barr body in breast and ovarian cancers.
Interest has recently reawakened in whether loss of the heterochromatic X chromosome (Barr body) is prevalent in certain breast and ovarian cancers, and new insights into the mechanisms involved have emerged. Mitotic segregation errors commonly explain the loss of the inactive X chromosome (Xi), but compromise of Xi heterochromatin in some cancers may signal broader deficits of nuclear heterochromatin. The debated link between BRCA1 and Xi might reflect a general relationship between BRCA1 and heterochromatin, which could connect BRCA1 to both epigenetic and genetic instability. We suggest that heterochromatic instability is a common but largely unexplored mechanism, leading to widespread genomic misregulation and the evolution of some cancers.
Pageau
Gayle J
GJ
Department of Cell Biology, University of Massachusetts Medical School, Worcester, Massachusetts 01655, USA.
Hall
Lisa L
LL
Ganesan
Shridar
S
Livingston
David M
DM
Lawrence
Jeanne B
JB
D001943:Breast Neoplasms / Q000378:metabolism / Q000473:pathology*; D041321:Chromosomes, Human, X; D005260:Female; D019398:Genes, BRCA1; D006570:Heterochromatin / Q000378:metabolism; D006801:Humans; D010051:Ovarian Neoplasms / Q000378:metabolism / Q000473:pathology*; D012728:Sex Chromatin / Q000378:metabolism / Q000473:pathology*
D006570:Heterochromatin