How fat can fight cancer

Irish scientist Lydia Lynch has won one of 15 international research fellowships given annually by Unesco-l’Oréal. An expert on the complex biochemistry of obesity, she travels to Harvard this month to begin working with a senior research scientist in Boston

A NEW WEAPON in the war against cancer could be found in humans if a new research project bears out. The work is being undertaken by Irish woman Lydia Lynch, who was recently awarded a Unesco-L’Oréal International Fellowship, along with 14 other researchers from around the world.

Lynch, who is based in University College Dublin and works with the Obesity Research Group in St Vincent’s Hospital, is the first Irish researcher to be awarded the prestigious prize, and will use the support to further develop her research into the immune system and obesity.

Her original research was on why some obese people are immune compromised, but under the Unesco-L’Oreal fellowship, it will particularly concentrate on how fat could potentially be used to fight cancer.

Patients in her research have a body mass index (BMI) of more than 40, in the super-obese category. “We found their natural killer cells are depleted in their blood compared to lean people,” says Lynch.

“The natural killer cells are the body’s first line of defence against cancer and viruses. Obese people get more cancers.” The new findings are “fairly shocking \ 40 per cent of certain cancer is due to obesity.” she said. The study also found that people living with obesity have less effective killer cells, with research showing that the immune cells don’t kill cancer under lab conditions.

The Unesco project expands further on this study. “We’re looking into the fat, the omentum fat, which is the thin layer of fat that hangs down from the liver surrounding the organs in the abdomen. It’s been called the policeman of the abdomen, because it can actually move around the body – something that nobody knows about except surgeons,” said Lynch.

Omentum can surround an infected organ, such as the appendix, to seal it off from the rest of the body and stop the infection spreading to the rest of the body.

“We thought that because omentum can carry out these healing jobs in the abdomen, it might have its own immune system,” she says.

“We found it does, and it is completely different from that anywhere else in the body. In particular, it has the largest – and first significant – population of these special killer cells, called invariant natural killer t-cells. These are really potent against cancer.”

Previous studies into mice found these cells throughout the body, but researchers could not locate the same cells in humans, until the omentum was studied more closely.

Research has already found that despite the higher levels of fat in obese people, they have fewer killer cells than lean people. The same is true for cancer patients, leading to the theory that this may increase susceptibility to cancer and infections.

The Unesco-L’Oréal fellowship programme chooses 15 young female researchers at doctoral or post-doctoral level every year, giving them up to $40,000 (€30,878) over a two-year period to pursue their research at an institution outside their home country.

Lynch chose Harvard, where research into the use of these cells is at a more advanced level than in Ireland. “They are one of the first in the world doing clinical trials with these cells,” she said. “There are a tiny few of these cells in the blood compared to omentum. They are trying to expand them and put them into patients to kill cancer.”

She will spend eight months in Harvard before returning to Ireland for a four-month period, and then making the trip to Harvard again. “The fellowship allows me to go over there, learn about the clinical trial, continue to work on the research and then bring it back to Ireland and establish everything I’ve learned in St Vincent’s Hospital.”

The move will be a family event for Lynch, with her partner, father and two children making the trip to the US to join her.

Aside from the benefits to Lynch’s own research, the Unesco-L’Oréal award is also significant in that it will help raise the profile of science, and particularly women in the sector in Ireland.

“In my lab, there are plenty of women working but none at the top, at professor level. My professor for my PhD, Cliona O’Farrelly, who is based in Trinity College, is an exception,” said Lynch. “Women are under-represented in science in Ireland.”