7 Reasons Cancer Cells Differ From Normal Cells

We all know that cancer is a malignant disease. But what exactly is "cancer"?

Cancer is a term we use to describe a group of diseases caused by abnormal changes in healthy cells in the body.

Our bodies consist of trillions of cells that enable them to function efficiently. So what happens to make cancer cells different from healthy cells? If you are curious, keep reading! We will explore seven ways cancer cells differ and what these differences mean.

Cell Shape

Healthy cells normally look alike. Cancer cells, however, look different from healthy cells and from one another. They are often oddly shaped, with indistinct edges, making it harder to see where one cell ends and another begins than it is with healthy cells. Another difference is the size of the nucleus. Almost all healthy cells have a nucleus, the cell's control center, which contains its DNA. Cancer cells may have more than one nucleus, and their nuclei are often much larger, taking up a great deal of space within the cell.

Can you see the differences between these two microscopic photographs of real cells? These microscope slides show how variable cancer cells are compared with healthy cells.

Damaged Genetic Code

Inside a cell's nucleus, within its DNA, you can find your unique genetic code. In healthy cells, DNA is tightly packed into 46 chromosomes. Cancer cells have errors in chromosome number that interfere with healthy division; these cells may have more or fewer chromosomes than normal. During normal cell division, chromosomes line up in a particular way to ensure that each new cell receives an accurate copy of every chromosome. Faulty chromosomes make proper division difficult, so further problems arise as the cancer cell multiplies.

The contents of the nucleus are very different in cancer cells: they may have the wrong number of chromosomes, and those present are often broken because of missing or added segments.

Abnormal DNA

Abnormal changes in a cell's DNA, known as mutations , cause a cell to become cancerous. Our DNA contains thousands of genes that control everything from our hair color to how many times each cell can replicate itself.

These DNA mutations become dangerous when a cell cannot stop replicating itself, forming a tumor that grows uncontrollably. Cancer cells may have many DNA mutations, causing them to ignore the body's normal rules.

Cancer cells have many errors and changes in their DNA. This may mean they can copy themselves much faster than healthy cells and may give them other capabilities that healthy cells lack.

They Do Not Stop Growing

One of the "rules" cancer cells ignore is "programmed cell death". Normally, when a cell becomes faulty or is no longer needed, a process that kills the cell is activated. This happens in our bodies every day without any problems. However, if a DNA mutation has disrupted the genes responsible for this process, the cancer cell survives to divide again.

Another "rule" is that healthy cells must receive a signal from nearby cells in order to divide , allowing our bodies to carefully manage the growth of tissue, a group of similar cells. Cancer cells, however, can divide without receiving this signal, continuing to multiply without limit and forming a tumor.

Healthy cells are allowed to divide only a certain number of times, but cancer cells find ways to divide indefinitely and form tumors.

They Hide From Our Immune System

Cancer cells can hide from our immune system . They do this in several ways, mostly by using proteins on the cell surface. These proteins act like a unique fingerprint that tells other cells what type of cell it is, such as a muscle cell or a nerve cell. When a cell becomes cancerous, its surface proteins may change because of numerous DNA mutations. Although this change should tell our immune system to kill the cell, sometimes the proteins make the cancer cell look normal, causing our immune system to ignore it. These proteins can also attract other cells that prevent our immune system from reaching the cancer cell (the tumor microenvironment). These are some of the ways cancer cells continue growing and multiplying enough to form a tumor.

Cancer cells find ways to hide from the immune system that seeks to destroy them. Our immune system uses cell-surface proteins to identify faulty or dangerous cells. Cancer cells sometimes disguise themselves with healthy protein markers, making them appear to the immune system to be healthy cells.

They Demand Nutrients

Healthy cells can send signals for blood vessels to grow closer to them. They do this only during normal growth and development, to ensure that new cells receive the resources they need from your blood. Cancer cells constantly send signals for blood vessels, even when they do not need additional resources to grow (this is called angiogenesis ). These new blood vessels supply the tumor with nutrients that enable it to grow faster.

Tumors attract far more blood vessels than normal tissue. This allows them to grow even larger as the blood vessels bring them nutrients.

They Spread Elsewhere in the Body

Another function of the new blood vessels is to provide easy access to the rest of the body. Once cancer cells enter the bloodstream, they can settle in a new location and become "metastatic", meaning that the cancer has spread from the original tumor to a secondary site. Normal cells do not do this because tiny proteins on their surfaces keep them in their proper place. However, mutations allow cancer cells to break away from the tumor and travel around the body.

Healthy cells stick together, whereas cancer cells cannot attach to neighboring cells because of DNA mutations. This makes it easier for them to enter the bloodstream and spread throughout the body.

These are 7 reasons cancer cells differ from healthy cells. Cancer research seeks to identify and use these differences to target cancer cells without killing healthy tissue.

In fact, many more than these 7 characteristics have now been discovered; we refer to them as the 14 Hallmarks of Cancer .

Because of cancer's diversity and variability, there is no single treatment suitable for every patient. Today, the integration of medicine and technology is enabling major advances in treatments directed at the specific characteristics of a patient's tumor. We can expect significant progress and innovations in personalized cancer treatment over the next 10-15 years.