This is probably going to be one of those posts that no one comments on. Oh well, I like writing them and I keep getting encouragement to continue (probably from people that don't know how to post!), so here it goes:
I remember my first exposure to the study of biology. In fact, I still keep in contact with my 8th grade science teacher (who, had after teaching us ecology, had us watch Philadelphia (movie about HIV-AIDS)). In college, I ended up studying biology from the perspective of someone interested in human ecology, but when I finally took my required course work during my senior year in organismic bio (note the 'ni')...I knew right then and there, that I wanted to go to medical school.
It is a very exciting time to be interested in both medicine and biology, mainly because of the revolution created by the field of molecular biology.
I just read a very interesting piece on the NYtimes called a Roller Coaster Chase for a Cure which explores some of the pertinent aspects of molecular biology. My favorite thing about this kind of reporting/writing is when someone takes complex scientific theories and produces rhetoric of clear, understandable english. The author does a pretty good job describing the article's protagonist and the general nature of cancer cells:
"But he (Penn Oncologist: Keith Flaherty) also chose the field (Oncology) because advances in understanding cancer’s molecular biology convinced him it might finally be possible to cure the disease — and he wanted to have a hand in it.
Healthy cells turned cancerous, biologists knew, when certain genes that control their growth were mutated, either by random accidents or exposure to toxins like tobacco smoke and ultraviolet light. Once altered, like an accelerator stuck to the floor, they constantly signaled cells to grow.
What mattered in terms of treatment was therefore not only where a tumor originated, like the lungs or the colon, but also which set of these “driver” genes was fueling its growth. Drugs that blocked the proteins that carried the genes’ signals, some believed, could defuse a cancer without serious side effects."
One thing that I would add, because it is the topic of my current research is this: it ain't just the genes. In many ways, individual cells are like people, they often group together according to various common factors or activities. Those colonies or communities of cells then interact with other communities of cells, much like when many different ecosytems come together to form the biosphere of the earth. Importantly, it isn't just what comes from the genes of one cancer cell that determines it fate, but actually the environment in which it is placed. For example, when the tissue of the esophagus is irritated by stomach acid, the cells release biochemicals into their local environment, which create inflammation. The soup of biomolecules that the cells are bathed is sort-of like the air we breath or the ocean surrounding fish. However, for some reason, there is an increased chance for cancer to develop in areas of chronic inflammation. The point then, is that the 'microenvironment' surrounding cells can have profound effects on which genes are 'turned-on' and which genes are 'turned-off'.
Once a tumor has formed, there are additional alterations to the micro-environment, sometimes favoring conditions that allow for the tumor cells the ability to dig their way into the circulatory system. Once there, they rarely, but occasionally have the ability to go back out of the circulatory system into some other site, set-up shop, and grow in that 'foregin' area (e.g. breast cancer spread to lungs, colon cancer spread to liver, prostate cancer spread to bone, etc).
I'm currently doing experiments on one particular protein that is characteristically found in elevated concentrations in the micro-environment of tumors which then become metastatic. When I say 'elevated', I mean relative to other tumors which are not metastatic and also relative to normal, healthy controls.
The cool thing is this; in a way, I'm still doing environmental science, just at a very, very tiny level!
ps- This is a pretty cool set-up, definitely up my alley