Experimental drug shows promise against cancer

A new study suggests that an anti-cancer compound studied for treating blood cancers may also help in treating cancers of the head and neck.

Richard Smith MD and Michael Prystowsky MD PhD, of Albert Einstein College of Medicine of Yeshiva University in New York, studied a new class of chemotherapy agents known as histone deacetylase (HDAC) inhibitors, which affect the availability of genes for transcription resulting in protein synthesis. In many types of cancer, out-of-control cell growth results from certain genes that are either too active or not active enough in producing proteins. HDAC inhibitors appear to combat cancer by restoring the expression of key regulatory genes that control cell growth and survival to normal levels.

The Einstein researchers focused on a particular HDAC inhibitor known as LBH589 that has already shown some success in clinical trials involving people with cancers of the blood. The researchers found that LBH589 succeeded in killing tumour cells that had been removed from head and neck cancer patients and grown in the laboratory. ‘This report shows that an HDAC inhibitor is effective on head and neck cancer cell lines, and that is the first step toward use in humans,’ said Richard Smith.

The researchers also identified a set of genes whose expression levels change in response to the HDAC inhibitors – a finding that may help doctors identify patients most likely to respond to the drug.

Future plans include testing LBH589 on head and neck tumour cells from more patients so that the set of genes that respond to the drug can be more firmly established.

The paper, The histone deacetylase inhibitor LBH589 inhibits expression of mitotic genes causing G2/M arrest and cell death in head and neck squamous cell carcinoma cell lines, is reported in the online edition of The Journal of Pathology.