Rome. An Italian working in the United States has unravelled the sequence of cellular events that triggers many cancers, raising hope for the development of drugs to break the chain.

Pier Paolo Pandolfi of the Beth Israel Deaconess Medical Center in Boston led a team who focused on one of the most interesting molecules discovered in recent years, ubiquitin.

Ubiquitin is so-called because it is present in every type of body tissue, earmarking waste matter to be disposed of.

Pandolfi's team discovered that, at the onset of many cancers, a protein called Hausp becomes hyperactive and eliminates the ubiquitin in the body's cells.

Without ubiquitin, another protein called Pten is freed from its natural home in the cell nucleus and loses its prime function of nipping cancer in the bud.

But a third protein, called Pml, could come to the rescue before the process starts, Pandolfi believes.

Pml may reduce Hausp's hyperactivity and stop it getting rid of ubiquitin, he says.

The important thing is to prevent Pten from escaping from the cell and keep it in there, fending off attacks from cancer cells. Pandolfi, whose study appears in the latest edition of Nature, says new drugs could stop the chain of events and prevent the onset of cancers like prostate cancer and leukemia.