Avenue Opens for New Ovarian Cancer Drugs

Posted on Sep 14, 2010 in Cancer

by Stephen Adams

At present the chemotherapy drug paclitaxel, also known by its brand names Paxol and Abraxane, is often prescribed to shrink ovarian tumours by stopping cancer cells dividing.

But some ovarian cancers are resistant to such drugs, known as taxanes, which are derived from the yew tree.

Now British and American researchers, partly funded by Cancer Research UK, believe they have opened up a new route after identifying a key protein.

They found that cells struggled to divide when they interfered with a gene known as SIK2, which produces the protein.

The discovery was a surprise because SIK2 was not known to be involved in ovarian tumour growth. 

It was previously only known to be active in fat and liver cells recovering from starvation.

By blocking the protein, they found that ovarian cancer cells became more sensitive to paclitaxel.

Dr Ahmed Ashour Ahmed, who undertook the research at Cambridge University, said: “What we found is that when you interfere with the function of this gene, cells struggle to divide.

“If you do that and also give Taxol then you have a very useful synergy between the two modes of therapy in inducing cancer cell killing,” said the academic, who is continuing his research at Oxford.

Dr Ahmed said women whose cancers were resistant to taxanes tended to be those with a high “expression” of the SIK2 gene.

The next task was to identify the right substances which stopped the action of the protein, Dr Ahmed noted.

Dr Ahmed worked on the study with Dr Robert Bast, of the University of Texas MD Anderson Cancer Centre. It was published on Monday in the journal Cancer Cell.

Dr Bast said: “In our search for proteins involved in drug sensitivity, we found that SIK2 was required for cell division and that its inhibition is potentially a new approach to treating women with taxane-resistant ovarian cancer.”

In the UK there are around 6,800 women diagnosed with ovarian cancer each year and around 4,400 deaths.