Why chemo works for some people and not others

Sep 18, 2008

MIT researchers have shown that cells from different people don't all react the same way when exposed to the same DNA-damaging agent — a finding that could help clinicians predict how patients will respond to chemotherapy.

The research team from MIT's Center for Environmental Health Sciences (CEHS) and the Departments of Biological Engineering and Biology, identified a group of 48 genes that can predict how susceptible an individual is to the toxic compound, known as MNNG. The work appears in the Sept. 19 online edition of Genes and Development.

MNNG, a DNA-damaging compound similar to toxic chemicals found in tobacco smoke and in common chemotherapy agents, usually kills cells by inducing irreparable DNA damage. However, the researchers found a wide range of susceptibility among cells taken from healthy people.

"A cell line from one person would be killed dramatically, while that from another person was resistant to exposure," said Rebecca Fry, former MIT research scientist and lead author of the paper. "It wasn't known that cell lines from different people could have such dramatic differences in responses."

Toxic agents such as MNNG create lesions in DNA, provoking the cell to defend itself with a variety of DNA-repair and other pathways. However, every individual expresses slight differences in the genes involved in those pathways.

"Even if everyone is exposed to exactly the same things, they would respond differently, because we're all genetically different," said Leona Samson, senior author of the paper, director of CEHS, and an American Cancer Society Research Professor.

The team members found that after measuring the expression of every gene in each cell line, they could predict cell sensitivity to MNNG from the expression of just 48 specific genes, with 94 percent accuracy.

Several of those 48 genes have already been linked to cancer, said Samson, but it was not known that their expression is already altered before exposure to the DNA damaging agent.

Source: Massachusetts Institute of Technology

Explore further: Project pinpoints 12 new genetic causes of developmental disorders

add to favorites email to friend print save as pdf

Related Stories

DNA sheds light on why largest lemurs disappeared

Dec 16, 2014

Ancient DNA extracted from the bones and teeth of giant lemurs that lived thousands of years ago in Madagascar may help explain why the giant lemurs went extinct. It also explains what factors make some surviving ...

Recommended for you

Obese British man in court fight for surgery

Jul 11, 2011

A British man weighing 22 stone (139 kilograms, 306 pounds) launched a court appeal Monday against a decision to refuse him state-funded obesity surgery because he is not fat enough.

2008 crisis spurred rise in suicides in Europe

Jul 08, 2011

The financial crisis that began to hit Europe in mid-2008 reversed a steady, years-long fall in suicides among people of working age, according to a letter published on Friday by The Lancet.

New food labels dished up to keep Europe healthy

Jul 06, 2011

A groundbreaking deal on compulsory new food labels Wednesday is set to give Europeans clear information on the nutritional and energy content of products, as well as country of origin.

Overweight men have poorer sperm count

Jul 04, 2011

Overweight or obese men, like their female counterparts, have a lower chance of becoming a parent, according to a comparison of sperm quality presented at a European fertility meeting Monday.

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.