CAMBRIDGE – A huge discovery made by the Wellcome Trust Sanger Institute, under the Cancer Genome Project. It disputed the textbook definition of cancer; a multi-stage cell development process, through a progression from a pre-cancerous lesion to malignant tumors.

Stephens and co-workers proved that cancer is the result of a single event called Chromothripsis, or “chromosome explosion”. Following this process, hundreds of genomic rearrangement occurs involving one or more chromosomes.

Chromosomes are shattered apart as it “explodes” into fragments of gene. Some are joined together by the DNA repair mechanism at random. This genetic “mix up” may lead to mutations in which, some, can trigger the development of cancer. In some cases, one or more cancer-causing lesions may appear.

Researchers also found that this catastrophe is present in 2-3% of cancer of many subtypes. It is more common to occur in bone cancers, in roughly, 25% of the cases.

Studies were made on the ‘stamp’ of Chromothripsis seen in cell samples which were collected from a 62-year-old patient with Chronic Lymphocytic Leukemia. It was taken when the she was first diagnosed. Another sample was taken 31 months later, following her subsequent clinical course which showed rapid deterioration.

Analysis showed that all rearrangements present in the pre-treatment sample were also present in the later sample. There were no new genomic rearrangements, suggesting that the process causing these complex rearrangements had resolved before the patient was first diagnosed.

Hence, this supported Stephens and his colleagues’ finding that the process occurs in a one-off cellular crisis. It has important implications in understanding genomic reorganization and temporary emergence of cancer.