Twenty years ago, chronic myeloid leukaemia meant a death sentence, with all patients dying within five years of the diagnosis.
However, a significant breakthrough made in cancer research in the 1990s changed everything, as researchers were successful in developing a targeted drug therapy for a genetic abnormality earlier associated with the disease.
Thanks to this drug, the life expectancy of chronic myeloid leukaemia patients now equals that of the average Finn.
“Chronic myeloid leukaemia was the first cancer for which the genetic mutation underlying the onset of the disease was found through research,” says Satu Mustjoki, a principal investigator and research group director at the Hematology Research Unit of the University of Helsinki and the Helsinki University Hospital. Mustjoki’s research group has been investigating haematological diseases already for a decade.
Answer in immunotherapy
The next important question is how to develop chronic myeloid leukaemia therapy for or apply it to other cancers. Mustjoki’s group is pursuing a curative treatment, since the current drug has adverse effects and is also quite expensive. At the moment, the group is investigating the reason for the ability of certain patients to stop using the medication altogether.
“It looks like the human defence system plays an important role. In some of the patients the defence system has become active, which may result in successful discontinuation of the drug therapy,” Mustjoki explains.
At the time, the newly-developed drug for chronic myeloid leukaemia engendered wide-ranging enthusiasm among researchers. It was thought that this model could be applied to developing functional therapies for other leukaemias and cancers.
In part, this holds true: the same drugs are also effective in certain patients with acute lymphatic leukaemia, and it appears that understanding the genetic mechanism of cancer has spawned other targeted therapies. Regrettably, not all types of cancer are equally simple.
“Usually, they consist of many different mechanisms, making it insufficient to inhibit a single aberrant protein with a particular drug. Combination treatments are required,” says Mustjoki.
Successful research requires time and money
Finland has plenty of top-level expertise, while the basic preconditions for conducting cancer research are in place.
“In Finland, samples collected from patients can be used for research, which is an important premise. Our universities also are closely connected with hospitals and the physicians providing care to patients, enabling the linkage of patient records with the cells under investigation. That cannot be taken for granted everywhere,” Mustjoki explains.
A good new example of collaboration between cancer researchers and treating physicians is the flagship project ICAN, which aims to find individualized treatments for patients.
The biggest challenge for Finnish cancer research is funding. Cuts targeted at universities in previous years have substantially complicated the conduct of the research here. Funding is scarce and the duration of funding periods is too short. If funding is secured for, say, a single one-year period at a time, it is difficult to plan ahead and be innovative, potentially resulting in many undiscovered breakthroughs.
Funding for doctoral dissertations and university research has also been curtailed, which is reflected directly on researchers. Employment and positions are harder to come by in Finland, making them direct their gaze abroad. Furthermore, funding has to be acquired from several sources, which takes time from the actual research.
Breakthroughs are the result of persevering work – and coincidence
Even though results in cancer research are elusive, they may eventually turn out to be revolutionary.
As an example, Mustjoki highlights James P. Allison and Tasuko Honju, Nobel laureates in medicine in 2018, whose original research topic was basic immunology, or the activation of T cells. At first, they did not consider themselves researchers of cancer immunotherapy, but only realised later that this was where their research had led them.
“After coming to understand the function of normal T cells and the effect cancer has on their function, it was possible to develop novel treatments, such as various antibodies for cancer immunology. In the last five years, revolutionary therapies transformative for cancer treatment have been developed,” Mustjoki says.
Had research funding been granted with a more short-sighted attitude, not considering, for example, the relevance of knowledge on the normal function of T cells, this breakthrough would never have come to pass.
The next breakthrough in the field of immunotherapy
Currently, promising immunotherapies are in use for a handful of cancers, such as melanoma and certain lung cancers. In addition, within the large group of other cancers, the efficaciousness of immunotherapy is so far uncertain.
“I think the next breakthrough in cancer research will be us gaining a better understanding of the individual characteristics of all cancer types and whether it is immunology or another factor that could be affected in each individual patient. To be able to provide the best possible care, it is important to identify the type of the cancer in question,” says Mustjoki.
As cancer is most prevalent among the aged population, increases in the lifespan have also added to the number of cancer cases. At the same time, cancer mortality has significantly decreased.
“Effective and well-functioning treatments have been developed for a number of cancers. Finns may draw comfort from the fact that we are at the very forefront of cancer treatment, with excellent treatment results,” Mustjoki points out.
Text: Eevi Näsänen
Photos: Johanna Taskinen