Interview With Michio Kaku, Author of 'Physics of the Future'

A. Right, that's the whole point. Chemotherapy is like a shotgun which kills ordinary cells as well as cancer cells. These nanoparticles, in trial now, just hone in on cancer cells. We're talking about a sea change in cancer research, going to the molecular and genetic basis of cancer, rather than hitting ordinary cells and hoping that cancer cells die faster than ordinary cells.

Q. When might this happen?

A. Five to 10 years for FDA approval; they are going through clinical trials now. This is extremely promising because now for the first time can you even think about zeroing in on cancer.

Q. In the book you say there are so many types of cancer that it will be a huge challenge to eradicate it.

A. Cancer is like the common cold; there are so many different types. In the future we'll still have cancer, but we'll detect it very, very early, so that it won't kill anybody. We'll zap it at the molecular level decades before it grows into a tumor.

Q. What advancements are being made in brain research?

A. In the case of stroke victims who are totally paralyzed and outwardly are vegetables, we can hook them up to a computer and they can surf the Web, play video games, solve crossword puzzles, answer email. They can write prose and communicate with people just by using their brain signals. This has already been done at Brown University.

Q. What about progress for degenerative brain diseases like Alzheimer's?

A. In the future we may able to get brain stem cells and inject them directly into your brain. These healthy cells would incorporate into your brain. You'll have to learn how to ride a bicycle again because your wiring will have been shuffled. Once you learn how, you'll be able to remember. You will have to relearn certain tasks but with a younger brain.

Q. So your memory function would be restored, but not your old memories.

A. That's right. You would have to relearn basic life skills, like being a kid again, really.

Q. What about slowing the aging process itself?

A. Even more astonishing, we're beginning to understand the molecular mechanisms of aging and isolate the genes behind it. For example, we live twice as long as the chimpanzee, but genetically we are 98.5 percent identical to the chimpanzee. This means that just a handful of genes have doubled our lifespan. So scientists are now zeroing in on those, trying to find out which ones are responsible.

Q. What will we know about our own genes?

A. All of us will be able to have a CD-ROM with all our genes on it. Today, if you wanted to sequence every single gene in your body, it would cost $50,000. In the future, the cost will go down to a few thousand dollars, and maybe after that, a hundred dollars.

Q. How will that be helpful?

A. If we can then sequence the genes of old people by the millions and young people by the millions, and subtract, that will tell us exactly where aging is concentrated in the body.

Q. So what to do with that, then?

A. Aging is basically the build-up of error: error at the genetic level, error at the cellular level. Cells normally repair themselves, that's why you heal when you get a cut. But even the mechanism of repair eventually falls apart. Error builds up. So if we know which genes are involved, we can make sure that those genes don't wear down. There's another effective way to stay youthful, and that's caloric restriction.

Q. That doesn't sound fun at all.

A. Exactly. We want the gene that will mimic caloric restriction without having to starve.

Q. What happens when you actually do starve yourself?

A. Your cells don't age quickly, but you become sluggish, lethargic, you lose all interest in sex, you lose all joy, you become depressed. We want to isolate the gene that will give you the benefit of caloric restriction without you having to starve. Several candidates have been proposed. At Harvard, there's a gene called SIR2 that's being looked at very carefully. It is also linked to red wine.

Q. This is the resveratrol effect?

A. Yes, but you have to be very careful. SIR2 and resveratrol are not the fountain of youth. If you go to the drugstore, there are all these promises of "lose 10 years"; most of those claims are fake. They can get away with it because those products are unregulated by the FDA; they can say pretty much whatever they want. The media, of course, loves to make claims about the fountain of youth. Don't believe it. No one has it. But we're getting close.

Q. So what will that fountain of youth look like?

A. In the future, I can imagine that we will genetically modify ourselves using the genes that have doubled our life span since we were chimpanzees. We'll also make sure that the genes' repair mechanisms are intact so that the cells remain young, and we'll reset all biological clocks and use genes like SIR2 which will give us the benefit of caloric restriction. We're not there yet, so don't believe products that claim it. However, I can see that our grandkids may grow up to be 30, and just stop.

Q. Stop?

A. Yes. Our grandkids may not want to age beyond 30. It's reasonable to assume that they'll have that option. Our kids are going to see the beginning of this and will be the first generation to benefit. Our grandkids, by the time they grow up, may actually have the ability to stop aging at a certain point.

Q. Please explain tissue engineering?

A. Organ failure is one reason for health to decline. Right now we can grow organs in the laboratory from your own cells. We can grow heart valves, blood vessels, bone, noses, ears. The first bladder was grown four years ago.

Q. How?

A. We get a sponge — a mold in the shape of an ear, bone, nose. We put in cells from your own body so there is no rejection mechanism, and hit it with growth factors so it proliferates. The plastic is biodegradable.

Q. When will these move from labs to actual transplants?

A. That will still take time for FDA approval — five to 10 years. The first liver will probably be grown in five years. That'll be huge because liver failure is a very common health problem.

Q. What innovations in the book will help people improve their lifestyles?

A. In the future, you will have the Internet in your contact lens. You'll blink and go online. If you want to have a bridge game with three people in Alaska, Russia and South America, you simply blink and see the images of people around a table.

Q. Good-bye loneliness.

A. Once the Internet is in our contact lens or glasses, we'll be able to make contact with old friends and new — hobbyists who share our interests.

Q. And no language barriers in the future?

A. Already Google has been able to take a human voice in English and translate it into Chinese and other languages. This means that your contact lens will identify whom you're talking to, print out their biography as you're talking, and display what they're saying in English. So when you are a tourist you will be able to bargain with anyone, in any language. You'll be able to speak at any international conference. Some people say that's centuries away, but no, we're talking about a decade from now.

Q. I'm very interested in the driverless car. Tell us about it.

A. Google is spending millions to perfect it. Their target is eight years from now. The car is actually safer than a human, believe it or not. Humans make mistakes, get distracted, fall asleep, get drunk. We want the car to be perfect, which will take time, but it's already safer than a human driver.

Q. Will driver's licenses disappear?

A. In the future, you'll just talk to your car and tell it where to go. It will figure out the best paths, download traffic jams on the Internet, and just take you where you want to go. Restrictions on mobility will be removed as cars become driverless. We'll be chauffeured, basically.

Betsy Towner lives in California.