Fang Fang researches ALS and cancer

Text: Cecilia Odlind, first published in Swedish in the magazine Medicinsk Vetenskap no 2, 2017.

THE DISEASE means that the nerve cells that control the body's muscles gradually atrophy, leading to general paralysis. Amyotrophic lateral sclerosis, ALS, has no cure today and causes great suffering in those who contract it. In Sweden, several hundred people a year contract the disease and despite the increasing incidence the field of research is still a small one. Researcher Fang Fang’s interest began during the course of her doctoral studies, when she was a member of one of the few research teams in the world who were studying risk factors for contracting ALS and factors that can affect the prognosis. Since then she has felt extra strongly for this patient group.

“When I was studying to be a doctor, I realised that it is difficult for me to see people suffer; I wouldn’t have made a good doctor. So I became a researcher and hope to contribute more knowledge instead,” says Fang Fang.

Finding the critical risk factors requires a good foundation of patient data. In one of Fang Fang’s most recent studies, where she collaborates with ALS patients’ doctors, all patients in Stockholm newly diagnosed with ALS, as well as their siblings and partners, are asked to participate.

“More than 95 per cent of the patients accepted. They want to help us in our search for an effective treatment,” she says.

And more knowledge is needed. Today there is only one drug that is approved for treating ALS and it can only prolong survival by a few months.

“I think different approaches will be needed for different patients since the underlying causes probably vary,” says Fang Fang.

One piece of the puzzle that she and her colleagues have contributed is that patients with ALS are often thinner than average. Conversely, people with a high body mass index and people with type 2 diabetes run less risk of contracting ALS. Why this is so is not known. At the same time, the research team also found that ALS patients often have high levels of harmful fats in their blood, something often seen in fact in diabetes patients.

“These somewhat contradictory findings surprised us. In further studies that have not yet been published, we were able to find a partial genetic explanation for the elevated blood lipid levels,” Fang Fang says.

That a particular genetic blood lipid profile is more common among ALS patients may be of little comfort - one cannot change one’s genes. But Fang Fang still hopes that this knowledge can be put to clinical use.

“If you can help the patient adjust their blood lipid levels by for example changing their diet or with medication, it might be possible to improve their chances of survival after the diagnosis,” she explains.

A prolonged life would mean a lot to people who contract ALS. It often takes up to a year from the first symptoms before a diagnosis is made and patients often live for just 2-3 years afterwards. About 10 per cent of people who contract ALS live for up to 10 years after diagnosis.

“Why a small proportion of patients are able to live with the disease for a long time is one of the important questions that remain for research to answer,” Fang Fang says.

Another observation that the research team made through studies of Vasaloppet skiers is that elite skiers run double the risk of contracting ALS. People who ski for exercise on the other hand had a 50 per cent lower risk.

“Moderate exercise seems to be good but not in excess. We’re not sure how all this fits together but perhaps it can be explained by injuries that elite athletes suffer,” says Fang Fang.

“I like a good detective story. And my work as a researcher involves detective work where I am driven to find pieces of the puzzle and join them together into a complete picture,” Fang Fang goes on.

HER GOAL is to understand more about why ALS is more frequently contracted by thin, athletic people with high energy metabolism levels. Together with neurologists the team is examining blood and cerebrospinal fluid samples from ALS sufferers.

She and two colleagues, a psychologist and a cancer epidemiologist, are trying to solve another puzzle: how severe stress is linked to cancer. “This is a research question that has been debated for a long time,” she says.

“We are interested in both the question of whether severe stress can cause cancer and if this can affect the prognosis for sufferers,” she says.

In several studies, the research team has seen that serious events in life such as the loss of a child or suffering post-traumatic stress and depression earlier in life increase the risk of several forms of cancer, for example lung cancer. This might possibly be explained by grief or mental ill-health causing us to live less healthily and not taking care of ourselves. But results from a recently published study point to a more concrete biological explanation.

“Here again, we saw that women who had lost a child had an elevated risk of contracting cervical cancer later. But we also saw that these individuals had an elevated risk of becoming infected with the HPV virus, which is associated with this type of cancer. They also had higher levels of the virus in their body and they more frequently had the type of virus that is linked to high cancer risk. The results suggest that these women have a weakened immune system due to the psychological stress they had experienced, even if causality cannot be established solely on the basis of these observations,” says Fang Fang.

It is also known that patients with cancer contract other diseases like cardiovascular diseases and mental ill-health to a greater extent. This was long considered to be a kind of side-effect of the disease or the cancer treatment.

“But contracting cancer is for most people a psychologically very stressful experience. We were one of the first research teams to be able to show that these problems, and in particular those who come quite soon after their diagnosis, can largely be explained by severe psychological stress,” Fang Fang says.

THESE FINDINGS were later confirmed in several other international studies. The time between suspicion of cancer and possibly being diagnosed with the disease is a critical period. The time may certainly allow patients to process the idea of a cancer diagnosis.

“But many are forced to wait for several months before they find out. It’s often a very distressing period because you don’t have any information about the prognosis and can’t begin any treatment,” Fang Fang explains.

In a smaller study, Fang Fang had seen indications that people with a history of psychiatric diagnoses feel especially bad from having to wait a long time for treatment.

“It’s likely that different individuals can handle the waiting differently well,” she says.

Together with her colleagues Fang Fang now intends to study what happens in the body during this period, for example how stress hormone levels change. For some people, the waiting ends with a positive result – they do not have cancer.

“But they have gone through the same arduous process. This group of individuals has not been studied enough. It would be interesting to investigate whether they too are affected health-wise by their experience in the longer term,” she says.

Another thing that Fang Fang and her colleagues have discovered is that cancer patients have an elevated risk of injuring themselves in accidents. Prior to the cancer diagnosis accidents can often be explained by lack of attention; patients are distracted by all the thoughts that come into their heads, and fears about what they will be told. After the diagnosis their anxiety continues to distract them but then the researchers can also see an increase in intentional carelessness.

“In extreme cases, it’s a matter of self-harm behaviour and suicidal behaviour. A carelessness regarding one’s own person seems to appear after the diagnosis. We want to study this more closely,” she says.

Her colleagues say Fang Fang is very efficient: “No one can really keep up with her pace.” But the research takes a long time nonetheless. This is something she has learned to live with.

“I work methodically and as much as I can and hope that it will benefit patients in the future,” she explains.