Sunday, February 25, 2007

Six Cell Rules Broken by Cancer

How do cancer cells do their thing? Why are they so dangerous? Why can there be cancer in essentially each organ of our bodies? What makes them break the rules of cell existence? I have no answers to any of those questions, and as far as I can tell, the scientists don't know a whole lot more than I do about the origins of cancer. But, since I was diagnosed with gallbladder cancer, I have been trying to acquire a real layperson's understanding of the disease. I just read an article that helped me (although, goodness knows, I didn't understand all of it). Mostly, I really, really learned a lot from a small side box to the article entitled "Hallmarks of Cancer."

The article is in the March, 2007 edition of Scientific American, and it's entitled "Mapping the Cancer Genome," about efforts to begin mapping the genes involved with cancer as a way of learning more about the disease in general, and hopefully, ways to treat it. The project is called the Cancer Genome Atlas Project, and the plan is for it to follow the pattern established by the Human Genome Project, which completed mapping of the human genes about three years ago.

But the sidebar talks about the SIX rules of cell existence that are broken by cancer cells! How do they get away with it? Why don't our natural defenses step in after step 1, or 4, or 6 is broken? In the article itself, the author comments that "Some mutations may disable genes that normally protect against abnormal cell behavior, whereas others increase the activity of disruptive genes. Most cells must acquire at least several of these alterations before they become transformed into cancer cells - a process that can take years." (p. 52)

The sidebar begins by commenting the six abnormal capabilities listed below together give tumors their lethal power to overrun their native tissue and spread through the body.

Here are the Six Cell Rules Broken by Cancer:

1. "Self-sufficiency in growth signaling. Cancer cells amplify external growth cues or generate their own."

2. "Insensitivity to antigrowth signals. Cancer cells become deaf to quiescence cues from surrounding tissue." (I'm a little fuzzy about this one, but I think it means that cells signal each other that it's time to grow or time to stop growing, but cancer cells don't listen to the "stop growing" message.

3. "Evasion of Cell Suicide. Mechanisms that should trigger or carry out a self-destruct program in damaged cells are disabled or overriden." (This is the apoptosis I've been writing about for months.)

4. "Limitless replicative potential. Cancer cells evade intrinsic limits on the number of times a normal cell can divide."

5. "Sustained blood vessel growth. Tumors emit signals promoting the development of new blood vessels to deliver oxygen and nutrients." (This is why one of the most promising new anticancer drugs, Avastin, is in trials for most/many cancers. It was included in the clinical trial originally proposed to me last summer, and I may still add it to the regimen.)

6. "Invasiveness and motility. Cancer cells defy multiple signals and forces that hold a cell in place and prevent it from traveling to - and thriving in - other tissues." (This is the metastasis that is so dangerous to those of us with cancer, where the cells wander about the body until they find a spot to settle, divide, and grow, and become a danger to this new organ.)

Anyone reading this with more knowledge of biochemistry and these statements, please feel free to chime in!

So, today is Day 10 of this cycle, and I felt really, really tired and sleepy earlier in the day, but have felt better as the day went on. I told folks at church I felt "floppy." Now I'm not peppy, but better. I was nauseous a lot yesterday, and had better appetite today. Now I'm on the downward slope of this cycle, and hoping that each day is better than the one before. Twelve days until we leave for St. John! Yeah for sunshine and swimming!

1 comment:

Elaine Pascale said...

Hi Lynne
Thanks for sharing that research. I have told you that my father, a non-smoker, had mouth and throat cancer and I probably waste a lot of time imaging "reasons" for it (we were too close to Three Mile Island, mouthwash, my mother [yes, Freud, my mother is usually behind every conspiracy theory I have]). That information was helpful in getting me to give up my final grasp of conspiracies.
So glad to read in the earlier post that the spot is smaller. I'm picturing it disintegrating into nothing and I"m picturing you having a great vacation very soon!