– Pancreatic cancer is linked to the blood group

There has been a lot going on in cancer medicine in recent years.

But not for all cancers. As for pancreatic cancer – which kills more than 700 people in Norway each year – it is far from the spotlight.

Almost nothing has happened in the development of new treatment methods. Doctors have little to offer and the disease is in most cases a death sentence. Only five percent of patients are still alive, five years after diagnosis.

Read also: Very fatal cancer increases in the EU

But recently, Norwegian researchers have made a discovery that could lead us to better understand what creates the dangerous form of cancer. And then, what we can do to fight it.

Read also: This cancer may soon take more life than breast cancer

Different blood group – different risk

PhD student Khadija El Jellas and her colleagues at Haukeland University Hospital compared the blood group among Westerners with pancreatic cancer to two different groups of people from the same region in Norway.

The results showed that there appears to be a correlation between blood group and disease risk.

– We found that people with blood type A had a slightly increased risk, while those with blood type 0 were slightly more protected than the average, says Professor Anders Molven of the University of Bergen, who leads the group Haukeland.

This is consistent with previous studies of the population of other countries.

Read also: Why do we have different types of blood?

Molven however emphasizes that there are small differences. People with blood type 0 can still contract pancreatic cancer and the risk of developing this type of cancer is still low for people with blood type A.

Nevertheless, the connection can be interesting. He can say more about what is behind the scary disease.

Read also: Pancreatic cancer is not that a disease

May affect intestinal flora

What kind of blood group can have with cancer?

For now, nothing is safe. But the researchers have some assumptions, says Molven.

One is about intestinal bacteria.

The fact that we have different types of blood actually means that our blood cells are not exactly the same. In addition to some of the proteins found in blood cells, there are special sugar molecules. And they can be different.

People with blood group A and B have an extra sugar molecule compared to people with blood group 0. That's why there can be blood transfusion problems, for example if a human being 0 blood group receives a blood.

The recipient's immune defense perceives A sugar molecules as something that does not belong to the body. Instead, he considers the blood as a stranger and initiates a violent immune response.

Read more: Why can not you mix blood?

However, recent years of research have shown that these sugar molecules in particular do not appear only on blood cells. They are also found on certain cells of the intestine. And again, different intestinal bacteria attach to varying degrees on intestinal cells with molecules A, B or O.

– There is good evidence that different types of blood can cause some differences in intestinal flora. It is also known that the intestinal flora can affect certain types of cancer. One can imagine that the blood group changes the intestinal flora, which affects the risk of pancreatic cancer, says Molven.

May be due to the immune system

Another hypothesis concerns the immune system.

This is important for the body's ability to fight cancer.

Molven says that cancer cells often change the molecules on the surface. And sometimes, they can be modified to look like sugar molecules characteristic of blood cells, for example A.

In this case, the immune system of a human blood group A will not perceive the cancer cell as foreign. On the other hand, the immune system would have one with the blood group 0. Thus, people with blood group 0 would defend themselves better against such cancer cells.

In addition, the research team found something fascinating:

It seems that the blood type affects in one way or another what happens in the pancreas.

Also on digestive enzymes

– We have studied one of the digestive enzymes produced and excreted in the pancreas, explains Molven.

It turned out surprisingly that this enzyme also had the sugar molecules in the blood group on the outside.

– There is therefore a common pancreatic enzyme modified according to the type of blood. We are now wondering if this has anything to do with the risk of cancer.

Perhaps through the influence of intestinal flora? Molven believes that the results of the enzyme could be consistent with the hypothesis of intestinal flora and the immune system. Even both at the same time.

Here, however, there is still a long way to go to get answers.

Professor Caroline Verbeke of the University of Oslo is always optimistic.

She is the leader of the Pancreatic Cancer Network Norway, which works for a better treatment of pancreatic cancer.

Important research

– The results are interesting because they connect things that we had not seen before, says Verbeke.

In particular, she thinks that the results of blood group characteristics on digestive enzymes are both surprising and exciting.

For now, it's hard to say what the results will mean for understanding pancreatic cancer, but at best, this may give us a better chance of preventing this dangerous disease.

Read also: Presence of early signs of pancreatic cancer

– Above all, it is important to know more about the risk factors for pancreatic cancer. Most people can not do anything, like genes. But if it is also microorganisms of the digestive system, we can perhaps influence them.

In this area, any improvement is welcome.

Impossible mission

Today, only cancers of the lungs, colon and prostate die each year more than pancreatic cancers. By the year 2030, this type of cancer should be in second place.

Read also: Snus acquitted – do not be afraid of the type of cancer

Although research in recent years has improved the treatment of many other cancers, the development of pancreatic cancer has remained virtually silent.

– Pancreatic cancer has been almost neglected until recently, says Verbeke.

This is probably due to a certain extent to the fact that it is a very difficult form of cancer. A kind of impossible mission for cancer researchers.

– It's hard on all levels!

In other cancers, there may be one or more mutations behind, while pancreatic cancer has piles. Then it is also very difficult to find a treatment that works, says the professor.

– In addition, there are large differences in the genetic and epigenetic changes from one patient to another and between different parts of the same tumor.

This is probably the reason why doctors do not make chemotherapy work at the same time on the entire tumor.

The pancreas is also located near large blood vessels, which limits the amount of cancerous tissue that can be removed by surgery. In addition, the tumor contains a large amount of connective tissue, which can prevent chemotherapy from reaching the cancer cells.

Read also: A radioactive drug can prolong the life of cancer patients

Too little too long

The main challenges and limited success have put a damper on research interest, explains Verbeke. Research communities have been small and fragmented and young researchers have been eclipsed. It also makes competition for research funding difficult. The field ended in a vicious circle.

– But it's not fair for patients.

– They receive little effective treatment and have no opportunity to participate in medical studies as they lack money and a solid academic environment.

Verbeke now believes that it is important to educate the authorities and most people about pancreatic cancer, as well as to motivate doctors and researchers to take up this challenge.

– It's been too short a long time, and then it's hard to update. But think it's starting to happen now – I'm optimistic!

reference:

K. El Jellasa, BB Johansson, K. Fjeld, A. Antonopoulos, H. Immervoll, H. Choi, D. Hoem, E. Lowe, D. Lombardo, PR Njølstad, A. Dell, E. Mas, SM Haslam and A. Molven, the mucinous domain of the pancreatic carboxyl ester lipase (CEL) contains 1/2 -glycan nuclei that can be modified by ABO blood group determinants, Journal of Biological Chemistry, September 2018. Abstract.

K. El Jellas, D. Hoem, KG Hagen, MB Kalvenes, S. Aziz, S. Steine, H. Immervoll, S. Johansson, A. Molven, ABO Blood Group Associations and Pancreatic Ductal Adenocarcinoma: Influence on Resection Status . and Survival, Cancer Medicine, May 2017. Abstract.

Illustration: Haukeland kadijia

The article was first published by forskning.no