According to American scientists, a big step has been taken to block the chemical that plays a key role in the growth of several cancers.

The scientists have unpicked the structure of an enzyme known as telomerase and it helps to keep cells in an undying state when it is active.

In more than nine out of ten types of tumors, telomerase seems to work.

The study, which conducted by Philadelphia’s Wistar Institute’s researchers, has been published in the journal Nature

The telomeres serve as a natural clock in all cells in the body and it shortens every time when the cell divides.

The telomeres decrease to a certain length after a fixed number of divisions in most cells which can’t divide any more.  This is a key factor for changes in the ageing body that occurs when cell division slows down. Cells like stem cells in the embryo use telomerase to keep telomere length.

The chemical is hijacked by many tumors that use it as a fuel for their uninhibited growth.

The researchers have found a new method to record the formation of the most active part of telomeres.

Dr Emmanuel Skordalakes who led the study says that this record of the structure would assist to provide molecular targets for drugs.

Professor Rob Newbold, who is head of cancer research department in Brunel University, Uxbridge says that it is, indeed, a very important achievement.