Sengupta

CAMBRIDGE, Mass — If Archimedes had a tub for his •Eureka!' moment, then Shiladitya Sengupta had his balloons.

In the summer of 2002, Sengupta was riding the "T" — Boston's subway system — when he saw a man selling balloons that had smaller balloons inside of them. Sengupta immediately began thinking about his own research on cancer treatment that he was conducting for the biological engineering division of the Massachusetts Institute of Technology.

During the 35-minute ride to his laboratory, Sengupta felt an adrenaline rush and formulated the steps to design a cancer treatment modeled after those balloons. From that day on, Sengupta said he has been dedicated to his balloon theory, which is now known as nanocell cancer treatment.

Sengupta co-wrote his findings on the nanocell cancer treatment in the July 2005 issue of "Nature." Sengupta co-wrote the report with David Eavarone, Ishan Capila, Ganlin Zhao, Nicki Watson, Tanyel Kiziltepe, and Ram Sasisekharan, who all contributed to the research.

Last fall, Sengupta, 33, was recognized as one of the top technology innovators under 35 by MIT's "Technology Review" magazine. He also received a young investigator award from the American Society for Pharmacology and Experimental Therapeutics.

Sengupta, an assistant professor for Harvard Medical School and MIT, came to the United States in 2001 after receiving his doctorate in pharmacology from the University of Cambridge in the United Kingdom. He is originally from New Delhi, India, and he earned his bachelor's and master's degrees at the All India Institute of Medical Sciences in New Delhi. Sengupta now lives in Waltham, Mass., with his wife, Shivani, who also teaches at MIT. 

What Sengupta developed for cancer treatment stems from the idea of a balloon within a balloon. One balloon carries a drug to shut down the blood supply, and the second, smaller balloon carries a drug to kill the cancer.

Sengupta's nanocell cancer treatment has connected two important pieces of a puzzle many doctors and scientists could not piece together — how to cut off a tumor's blood supply and simultaneously deliver anti-cancer treatment to the infected cells. Sengupta's nanocell cancer treatment accomplishes both.

Sengupta explained that a tumor in a person's body needs nutrients to help it grow, and it receives these nutrients from the blood supply. What makes a tumor dangerous and possibly fatal, is when the tumor dispenses the now-infected blood back into the rest of the bloodstream. This can cause cancer cells to flow into other parts of the body.

Once inside the tumor, the first balloon's job is to cut off the tumor" blood supply, which starves the infected cells.

With other treatments, like chemotherapy, the blood supply could never be cut off because the anti-cancer drugs would not be able to reach the tumor.

When a tumor becomes hypoxic, or starved of oxygen, it starts to secrete enzymes. That's when the small balloon inside the big balloon releases an anti-cancer drug to kill the tumor. According to Sengupta, this is the first time that someone has been able to deliver anti-cancer drugs after the blood supply was cut off.

Sengupta said that the drawback to chemotherapy is that all of a person's cells are zapped with radiation — healthy and sick ones — which creates additional ailments for patients. Sengupta said his nanocell cancer treatment is specifically designed to only attack cancerous cells.

He added that his treatment only targets cancerous cells because the outer balloon is too big to fit into regular size cells. Cancer cells have a larger opening than normal ones, and the balloon is too big to fit into normal cells. Therefore, the outer balloon can only enter cancerous cells.

One of the key facets of nanocell cancer treatment is it does not have as many side effects as chemotherapy, which typically leads to hair loss, weight loss and other infections.

"Nobody thought of this before, so that is why the reviewers loved it," he says.

Sengupta said the smaller balloon will not burst inside the larger one. He added that the balloons, which are made of U.S. Food and Drug Administration-approved polymers and lipids, hold the drugs to stop the blood flow and the drugs to kill the tumor, separately. The smaller balloon will not burst until the first one has broken and all of the drugs it was carrying inside have been dispensed.

Sengupta has tested his cancer treatment in melanoma. In a black spot of melanoma that was the size of a quarter, Sengupta said chemotherapy reduced it to the size of a dime.

After Sengupta's nanocell cancer treatment, the melanoma was reduced "massively." He said that the melanoma was 75 percent smaller than a similar melanoma after chemotherapy treatment. 

He says many people are excited about his nanocell cancer treatment because it offers a better quality of life than chemotherapy, while also reducing a tumor's growth.

"It's a very simple thing — I mean, nothing great, but it has implications," he says.

Although Sengupta says his treatment is not a cure for cancer, he is optimistic that it can regress a tumor, but he is not sure if it can completely eradicate one. Sengupta also believes that his nanocell cancer treatment can give a patient a better quality of life, for a longer time.

Now Sengupta is extending his treatment to other kinds of tumors, like those of the brain and lung. He is searching for other combinations that could be used for different treatments.

"It's very logical, but nobody thought of this before. I mean, in fact I was thinking about this, like •Why didn't it strike me before, or strike anybody else before?'" Sengupta says.