Loss of p53 function promotes DNA damage-induced formation of nuclear actin filaments.

Tumor suppressor p53 plays a central role in response to DNA damage. DNA-damaging agents modulate nuclear actin dynamics, influencing cell behaviors; however, whether p53 affects the formation of nuclear actin filaments remains unclear. In this study, we found that p53 depletion promoted the formation of nuclear actin filaments in response to DNA-damaging agents, such as doxorubicin (DOXO) and etoposide (VP16).

The iron chelator deferriferrichrysin induces paraptosis via extracellular signal-related kinase activation in cancer cells.

Cancer cells generally exhibit increased iron uptake, which contributes to their abnormal growth and metastatic ability. Iron chelators have thus recently attracted attention as potential anticancer agents. Here, we show that deferriferrichrysin (Dfcy), a natural product from Aspergillus oryzae acts as an iron chelator to induce paraptosis (a programmed cell death pathway characterized by ER dilation) in MCF-7 human breast cancer cells and H1299 human lung cancer cells.

Simple and fast screening for structure-selective G-quadruplex ligands.

Structural selectivity of G-quadruplex ligands is essential for cellular applications since there is an excess of nucleic acids forming duplex structures compared to G-quadruplex structures in living cells. In this study, we developed new structure-selective G-quadruplex ligands utilizing a simple and fast screening system. The affinity, selectivity, enzymatic inhibitory activity and cytotoxicity of the structure-selective G-quadruplex ligands were demonstrated along with a structural selectivity-cytotoxicity relationship of G-quadruplex ligands.

Intramolecular G-quadruplex-hairpin loop structure competition of a GC-rich exon region in the gene.

We identified cytosine-rich regions adjacent to guanine-rich regions in protease genes. A typical GC-rich sequence derived from the gene showed structural competition between a G-quadruplex and a hairpin loop, and this competition significantly affected transcription efficiency. These results suggest an impact of neighboring sequences on the gene expression of guanine-rich sequences.

Photosensitizers Based on G-Quadruplex Ligand for Cancer Photodynamic Therapy.

G-quadruplex (G4) is the non-canonical secondary structure of DNA and RNA formed by guanine-rich sequences. G4-forming sequences are abundantly located in telomeric regions and in the promoter and untranslated regions (UTR) of cancer-related genes, such as and . Extensive research has suggested that G4 is a potential molecular target for cancer therapy.