Fast Genome Sequencer to Open Opportunities for Cancer Treatment

The UNM Can­cer Cen­ter will be among a small num­ber of sites world­wide to receive one of the first 20 units of the next-generation ion pro­ton genome sequencer.

Genome sequencers help researchers dis­cover the exact sequence of an individual’s DNA, which car­ries the instruc­tions for pro­tein man­u­fac­ture inside a cell. The instruc­tions are encoded in the DNA bases, or rungs of the DNA ladder-like struc­ture. If these instruc­tions go awry, the pro­teins that the cell builds may not func­tion prop­erly, and improp­erly func­tion­ing pro­teins can some­times lead to cancer.

Whole genome sequencers in use today are quite expen­sive, so can­cer researchers often nar­row their focus. “Right now we typ­i­cally sequence the one and a half mil­lion bases in the regions that are typ­i­cally involved in can­cer,” said Jeremy Edwards, asso­ciate pro­fes­sor of mol­e­c­u­lar genet­ics and micro­bi­ol­ogy and chem­i­cal engi­neer­ing at the UNM Can­cer Cen­ter. “With the ion pro­ton, we will be able to rou­tinely sequence the entire human genome, not just a small panel of can­cer genes. That’s a great advantage.”

Exist­ing whole genome sequencers can take two weeks to sequence an entire genome at a price of around $10,000. The new ion pro­ton genome sequencer will be able to sequence the entire human genome of 3 bil­lion bases in half a day for $1,000. This faster sequenc­ing means Edwards can rapidly ana­lyze an entire genome and use this tech­nol­ogy in the clinic. Com­par­i­son of the entire genome from can­cer­ous and non­cancer­ous cells from the same indi­vid­ual could be used to define can­cer treat­ment, a process known as pre­ci­sion medicine.

We know there are vari­a­tions in the genome because they’re what make us dif­fer­ent from each other,” Edwards said. The 3 bil­lion bases in the human genome typ­i­cally have mil­lions of poly­mor­phisms – sig­nif­i­cant dif­fer­ences – that are rec­og­nized vari­a­tions between indi­vid­u­als. But a can­cer genome has approx­i­mately 10 muta­tions that could be play­ing a role in the can­cer. It is a com­pu­ta­tional chal­lenge to find these dri­ver muta­tions and devise a ther­apy to treat the cancer.

Deter­min­ing an individual’s spe­cific vari­a­tions and the dif­fer­ences between can­cer­ous and non­cancer­ous cells in the same per­son will enable researchers and clin­i­cians to indi­vid­u­al­ize that person’s treat­ment even fur­ther by link­ing muta­tions to their cor­re­spond­ing pro­tein. “If we know where the muta­tions are, we can find out which ones are caus­ing pro­tein changes, what the pro­tein changes are, and where they are,” Edwards said. “Then we can deter­mine what we can do to help this per­son. What drugs are avail­able to tar­get this pro­tein?” Some­times, no drug that affects the pro­tein in ques­tion is avail­able, but there may be a drug that affects another part of the same chem­i­cal process within the cell. In the end, it’s pos­si­ble to rec­om­mend a pre­cise treat­ment for the individual.

Pre­ci­sion med­i­cine is still in its infancy. Only clin­i­cal labs can be used to dic­tate treat­ments for patients in the U.S., and they are mon­i­tored much more closely than research labs. How­ever, clin­i­cians can use data from research labs like Edwards’ as long as they con­duct their own inves­ti­ga­tion. The patient still ben­e­fits, but it’s a longer process. “The really big goal right now,” Edwards said, “is to bring this tech­nol­ogy into the clinic to improve people’s treatments.”

Media Con­tacts:
Dorothy Horn­beck, JKPR, (505) 340‑5929, dhornbeck@jameskorenchen.com
Michele Sequeira, UNM Can­cer Cen­ter, (505) 925‑0486, msequeira@salud.unm.edu

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