New cancer drug opportunities

An international study released this week in the prestigious journal Nature could revolutionise the way in which cancers are treated and potentially put an end to aggressive DNA damaging chemotherapies and radiotherapy treatments.

The study, entitled Single-strand DNA-binding protein hSSB1 is critical for genomic stability has identified and characterised a novel human single-stranded DNA binding protein (hSSB1). hSSB1 is an upstream sensor in the double-strand break response pathway - double strand DNA breaks are lethal if they are not repaired.

"Chemotherapy, which is highly toxic, is currently the only option for most cancer patients. Not only does chemotherapy kill off the cancerous cells, it also kills off healthy cells, leading to severe nausea, fatigue, hair loss and in some cases death," said co-author Dr Liza Cubeddu from the University of Sydney's School of Molecular and Microbial Biosciences.

hSSB1 is recruited to sites of DNA breaks where it co-localizes with other repair proteins. Cells depleted in hSSB1 are hypersensitive to ionizing radiation, which causes double-strand breaks that are not repaired efficiently.

"hSSB1 is a prerequisite for cancer cells to survive, normal cells can function without it," said Dr Cubeddu. "Developing a drug that can target the hSSB1 gene means that you can destroy cancerous cells while leaving healthy cells intact. This could revolutionise how cancers are treated and potentially put an end to aggressive DNA damaging chemotherapies and radiotherapy treatments," she said.