How Do Cancer Cells Behave Differently from Healthy Ones

How Do Cancer Cells Behave Differently from Healthy Ones

Recently, I came across a brilliant talk given by George Zaidan on TedMed.com describing how cancer cells behave differently from healthy ones. Oh my goodness, is this scientific process boiled down to the true nuts and bolts.

Below is the actual manuscript – in case you prefer to learn by reading.

We all start life as one single cell, then that cell divides and we are two cells, then four; then eight, cells form tissues, tissues form organs, organs form us. These cell divisions by which we go from a single cell to a hundred trillion cells are called growth. And growth seems like a simple thing because when we think of it, we typically think of someone getting taller or later in life wider, but to cells growth isn’t simple.

Cell division is an intricate chemical dance that’s part individual, part community driven and in a neighborhood of a hundred trillion cells, sometimes things go wrong. Maybe an individual cell set of instructions or DNA gets a typo, what we call a mutation.

Most of the time the cells senses mistakes and shuts itself down or the system detects a troublemaker and eliminates it, but enough mutations can bypass these fail-safe, driving the cell to divide recklessly, that one rogue cell becomes two, then four, then eight. At every stage the incorrect instructions are passed along to the cell’s offspring, weeks, months or years after that one rogue cell transformed, you might see your doctor about lump in your breast, difficulty going to the bathroom could reveal a problem in your intestine, prostate or bladder or a routine blood test might count too many white cells or elevated liver enzymes, you doctor delivers the bad news: it’s cancer.

From here your strategy will depend on where the cancer is and how far it’s progressed. If the tumor is slow growing, and in one place, surgery might be all you need, if anything. If the tumor is fast growing or invading nearby tissue, your doctor might recommend radiation or surgery followed by radiation. If the cancer has spread or if it’s inherently everywhere like leukemia, your doctor will mostly likely recommend chemotherapy or a combination of radiation and chemo.

Radiation and most forms of chemo work by physically shredding the cell’s DNA or disrupting the copying machinery, but neither radiation nor chemotherapeutic drugs target only cancer cells, radiation hits whatever you point it at, and your bloodstream carries chemotherapeutics all over your body. So what happens when different cells get hit?

Let’s look at a healthy liver cell, a healthy hair cell and a cancerous cell.

The healthy liver cell divides only when it stressed. The healthy hair cell divides frequently and the cancer cell divides even more frequently and recklessly. When you take a chemotherapeutic drug, it will hit all of these cells, and remember that the drugs work typically by disrupting cell division, so every time a cell divides, it opens itself up to attack, and that means if the more frequently cell divides, the more likely the drug is to kill it.

So remember that hair cell, it divides frequently, and isn’t a threat. And there are other frequently dividing cells in your body like skin cells, gut cells and blood cells. So the list of unpleasant side effects of cancer treatment parallels these tissue types, hair loss, skin rashes, nausea, vomiting, fatigue, weight loss and pain. That make sense because these are the cells that get hit the hardest. So in the end it’s all about growth.

Cancer hijacks cell’s natural division machinery, and forces them to put the pedal to the medal growing rapidly and recklessly, but using chemotherapeutic drugs, we take advantage of that aggressiveness, and we turn cancer’s main strength into a weakness.