Even when a tumor is all but eliminated by Taxol, a few cells with mutated microtubules that are invulnerable to the drug can remain, growing into more deadly tumors.

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Eventually, huge numbers of these mutated proteins build up, form insoluble masses within cells, which kill them.

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However, when it is mutated it is unable to do this, leaving cells at risk of becoming potentially cancerous.

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It seems to be particularly important for the growth and survival of some cancer cells and large amounts of the molecule are often present in the cells of non-small cell lung cancers, sometimes in a mutated, over-active form.

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Wong (now at Stanford University) figured the mutated gene might make an ideal target for a vaccine, as it creates an abnormal protein not seen in healthy cells.

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