Researchers discover key to cancer treatment

A major step toward the personalisation of cancer treatment has been made by an analysis of thousands of tumours that uncovered clues on how cancer is caused.

Researchers at Cambridge University Hospitals say it is possible to detect patterns -- called mutational signatures -- in the DNA of cancers for the first time, marking a significant step towards the personalisation of treatment.

The new research, based on tumours from more than 12,000 NHS patients, has found “a treasure trove” of new clues, allowing medics to develop a new tool to help match treatments to patients.

Principal author Serena Nik-Zainal, professor of genomic medicine and bioinformatics at the University of Cambridge said the discovery is important because “they (mutational signatures) are like fingerprints at a crime scene – they help to pinpoint cancer culprits.

Cancer cells can harbour thousands of different and unusual mutations but only a few are known to really drive the development of a tumour.

In the past, many cancers have been categorised by doctors based on where they are in the body and the type of cells involved, but whole genome sequencing can provide another layer of key information.

The causes behind the majority of these new mutational signatures are unknown and the researchers suggest this indicates there are plenty of factors that can trigger cancer that have not been discovered yet.

Identifying these signatures allows doctors to look at each patient’s tumour and match it to specific treatments and medications.

These patterns can only be detected through the analysis of the vast amounts of data unearthed by whole genome sequencing – identifying the genetic make-up of a cell.

Prof Nik-Zainal added: “It’s like looking at a very busy beach with thousands of footprints in the sand.

“To the untrained eye, the footprints appear to be random and meaningless. But if you are able to study them closely, you can learn a lot about what’s been going on, distinguish between animal and human prints, whether it’s an adult or child, what direction they’re travelling in, etc.

“It’s the same thing with the mutational signatures. The use of whole genome sequencing can identify which ‘footprints’ are relevant/important and reveal what’s happened through the development of the cancer.”

In Kenya, cancer is the third leading cause of death after infectious and cardiovascular diseases. From 2012 to 2018, the annual incidence of cancer increased from 37,000 to 47,887 new cases and mortality rose from 28,500 to 32,987 between 2012 and 2018 accounting for 16 percent rise.

Further data shows that the survival rate for cancer patients in the United States and other developed countries is 80 per cent compared to less than 30 per cent in Kenya, majorly due to late diagnosis.