Paper Chase is a research database designed to offer abstracts of research articles published in journals that have a highly rated impact factor as determined by ISI Impact Factor and PageRank. Abstracts are organized by date, with the most recently published papers listed first. 

Paper Chase

KDM4A lysine demethylase induces site-specific copy gain and rereplication of regions amplified in tumors.

Cell. Aug 1, 2013;154(3):541-55.
Black JC, Manning AL, Van Rechem C, Kim J, Ladd B, Cho J, Pineda CM, Murphy N, Daniels DL, Montagna C, Lewis PW, Glass K, Allis CD, Dyson NJ, Getz G, Whetstine JR.

Massachusetts General Hospital Cancer Center and Department of Medicine, Harvard Medical School, 13th Street, Charlestown, MA 02129, USA.

Abstract:

Acquired chromosomal instability and copy number alterations are hallmarks of cancer. Enzymes capable of promoting site-specific copy number changes have yet to be identified. Here, we demonstrate that H3K9/36me3 lysine demethylase KDM4A/JMJD2A overexpression leads to localized copy gain of 1q12, 1q21, and Xq13.1 without global chromosome instability. KDM4A-amplified tumors have increased copy gains for these same regions. 1q12h copy gain occurs within a single cell cycle, requires S phase, and is not stable but is regenerated each cell division. Sites with increased copy number are rereplicated and have increased KDM4A, MCM, and DNA polymerase occupancy. Suv39h1/KMT1A or HP1γ overexpression suppresses the copy gain, whereas H3K9/K36 methylation interference promotes gain. Our results demonstrate that overexpression of a chromatin modifier results in site-specific copy gains. This begins to establish how copy number changes could originate during tumorigenesis and demonstrates that transient overexpression of specific chromatin modulators could promote these events.