In many tumors this process appears to go into hyperdrive.

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These have been well known for years to be crucial gene defects in many common tumors.

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This suggests that the current study, which used people's recollections of phone usage, underestimates the risk of tumors in many users, he said.

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He says the reason why so many cancer drugs are fizzling in trials is that common tumors contain too many mutations for targeted drugs to work.

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In many cases MTOR drugs don't shrink tumors much but merely blunt their growth.

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As many as ten tumors can be targeted in one session.

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In a study conducted with many patients in Japan, 28% of non-small cell lung cancer patients saw their tumors shrink with Iressa, compared with 10% of Caucasians.

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Other brain cancer cells, by contrast, were incapable of forming new tumors, no matter how many were injected into the mice, Dirks wrote last month in the journal Nature.

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