Sequencing the human genome in cancer and leukemia

Armen Hareyan's picture
Decoding cancer genome

Scientists at Washington University in St Louis have decoded the genes of a woman who had acute myeloid leukemia (AML) and discovered a set of mutations that may have caused the cancer or aided it's progression, according to an article published today in Nature.

Washington University (who also provided the photo on the right of the leukemia cells), also noted in their press release on decoding cancer patient genome and published at HULIQ:

"The researchers discovered just 10 genetic mutations in the patient's tumor DNA that appeared to be relevant to her disease; eight of the mutations were rare and occurred in genes that had never been linked to AML. They also showed that virtually every cell in the tumor sample had nine of the mutations, and that the single genetic alteration that occurred less frequently was likely the last to be acquired. The scientists suspect that all the mutations were important to the patient's cancer."


What is the significance of this fascinating research? Well, this is the first time such sequencing has been done and may lay the foundation for more comprehensive genome-wide studies of this nature in other cancers.

Just two of the 10 mutations the researchers found had been linked to AML previously, so the other 8 were a new and fascinating find. They were able to do this by selecting cancer cells from the patients bone marrow and comparing them to normal, healthy skin cells. Being able to compare the patient's normal cells to the AML cells may allows scientists to start unlocking the hidden genetic transformations and ultimately, design new therapies that target the critical mutations.

Most work on cancer mutations has focused on a few hundred genes already suspected of being involved in the disease, not the 20,000 or so genes that make up the full human genome. In other words, how can you hit a target if you don't know what it is? Using this new approach, scientists can separate out which mutations are most relevant to that particular cancer patient and one day, we may be able to then determine which therapy would be most suitable for them based on the mutational analysis.

Clearly, identification of new mutations critically evolved in a cancer also means new targets for therapeutic intervention and design of new drugs based on inhibiting the specific gene or kinase, much in the way Gleevec targets the BCR-ABL gene in chronic myeloid leukemia (CML). If a similar approach could be designed for other cancers, then it is likely that more cost effective medications with fewer side effects may result in the long run. That's good news for patients.

Reported by Pharma Strategy Blog and reprinted under Crative Commons. -