DNA repair defects in cancer and therapeutic opportunities.

DNA repair and DNA damage signaling pathways are critical for the maintenance of genomic stability. Defects of DNA repair and damage signaling contribute to tumorigenesis, but also render cancer cells vulnerable to DNA damage and reliant on remaining repair and signaling activities. Here, we review the major classes of DNA repair and damage signaling defects in cancer, the genomic instability that they give rise to, and therapeutic strategies to exploit the resulting vulnerabilities.

Induction of BRCAness in Triple-Negative Breast Cancer by a CDK12/13 Inhibitor Improves Chemotherapy.

In this issue of Cancer Cell, Quereda and colleagues report that a newly developed specific inhibitor of CDK12/13, SR-4835, sensitizes triple-negative breast cancer cells to PARP inhibitors and DNA-damaging chemotherapeutics by reducing expression of the genes in the DNA damage response pathway.

Chromatin Spread Preparations for the Analysis of Mouse Oocyte Progression from Prophase to Metaphase II.

Chromatin spread techniques have been widely used to assess the dynamic localization of various proteins during gametogenesis, particularly for spermatogenesis. These techniques allow for visualization of protein and DNA localization patterns during meiotic events such as homologous chromosome pairing, synapsis and DNA repair. While a few protocols have been described in the literature, general chromatin spread techniques using mammalian prophase oocytes are limited and difficult due to the timing of meiosis initiation in fetal ovaries.