Cell biology and blood cancer for dummies

In the interest of full disclosure, I have no science background. To the contrary, science was my worst subject in high school. So when I was diagnosed with cll four years ago and read up on it, I was immediately overwhelmed with terms like 13q, CD 38, monoclonal antibodies and mutated IGHV. When my doctor told me my beta2 microglobulin was high, he might as well have been speaking Chinese to me.

It has taken me several years to have some rudimentary understanding what my blood cancer is. I think I would have understood it faster if I had started out with some basic understanding of cell biology and how cancer works. Cancer is a group of diseases that involve abnormal cell growth. For us with blood cancer, its blood cells gone bad, more on that later. First we have to know what a cell is.

Cells (from latin word cella meaning small room) are the tiny building blocks of all life. Cells are very complicated little blocks, but basically are just a gel like material with a nucleus surrounded by a membrane. We have different types of cells like skin cells, brain cells, bone cells, stem cells and blood cells. We have about 50 trillion cells at any one time that live and die, or at least our normal ones do. Would you believe we have about two million red blood cells die each second? Cells dying naturally and being replaced by younger healthy cells is a good thing.

For any number of reasons, known and unknown, our cells can turn abnormal and start multiplying and stop dying like normal cells are programmed to do. That is cancer. If our brain cells go bad, we get brain cancer. If our skin cells go bad, we get skin cancer. If our blood cells go bad, we get blood cancer.

In our blood we have cells that perform different functions. Red blood cells bring oxygen to our organs. Platelets keep us from bleeding to death. White blood cells are the little soldiers of our immune system that fight infections. most blood cancer is a disease of our white blood cells.

To make it more complicated, we have different types of white blood cells that perform different functions, like having a navy, army and air force in our blood. We have five main types of white blood cells, the two we most talk about with blood cancer are lymphocytes and neutrophils. Lymphocytes (b cells) secrete antibodies. Antibodies are little warriors that seek out and neutralize viruses and bacteria. Neutrophils help fight bacterial infections in a different way.

CLL is a cancer which starts in our marrow which makes too many lymphocytes, hence the name cll (chronic “lymphocytic” leukemia). The lymphocytes spread to our lymph nodes through the blood where they multiply. CLL is often diagnosed incidentally when we have a blood test which shows our white blood cell count is high. But its not all of our white blood cell types that are high with CLL, it’s just the lymphocytes. That’s why you might read so many on here discuss their absolute lymphocyte count.

Put another way, CLL is when our lymphocytes go bad, multiply and will not die a normal death. Instead of living and dying like our healthy cells do, cll cells live on longer and crowd out our good cells. But how do our doctors know if our lymphocytes are CLL? Okay, that’s even more complicated yet, I hope I am not losing you.

We have to go back to cell biology to understand this. Remember that cells are just these little living building blocks surrounded by a membrane. As it turns out, there are all kinds of molecules that reside on the surface of our cells that regulate our cells in different ways, including how our cells live and die.

Scientists have assigned these molecules numbers to distinguish among them. Ever hear of CD38, CD19 and CD20? Those are just the numbers assigned of some of these molecules (regulators) that can live on our CLL cells. CD stands for cluster of differentiation. Really? Seems like more of a cluster you know what to me. Scientists call these CD things “markers”. Think of them as fingerprints.

Without getting too complicated, our CLL has unique CD markers (molecules on the cell surface of our lymphocytes gone bad), that identify the cells as cancerous lymphocytes. Some of you have heard of flow cytometry. This is a test they use to look for these markers. CLL cells usually “express” CD5, CD19 and CD20 molecules on their surface. If a molecule is over expressed, that means there are more than there should be, under expressed means less than normal. Other types of leukemia may over express other CD markers. Doctors use these markers as fingerprints to see what type of leukemia we have.

Scientists are using cell biology to help treat us. They try to figure out what surface molecules are keeping our bad cells alive and then create drugs targeting those molecules and program them to let the bad cells die (apoptosis). That’s an over simplification, but its generally true scientists focus on these abnormal markers and figure out ways to target them to treat us.

One challenging problem is that some or our remedies have a hard time distinguishing the good cells from the bad cells. Remember we said neutrophils are a type of white blood cell that fight bacterial infections? Well some of the treatments we use to kill our blood cancer lymphocytes also kill our neutrophils. That is called an off target effect. The lymphocytes are the target, not the neutrophils. Certain treatments we undergo for cll lower our neutrophils (neutropenia) which makes us more at risk for bacterial infections.

Well I have rambled on enough. How all the different drugs work for us is a topic for another day, I am sure this explanation of cell biology has left some more confused than when they started.

And I also defer to the true scientists on here as I do not really understand this stuff on a scientific level and in trying to dumb it down for me to understand, may have gotten some points wrong.

But I think most of this is generally correct and took me a long time to understand, if I really do. If this is helpful to anyone, I’ll take a shot at treatment options for dummies next.