Cancer in 3D

Incorrect Cancer Knowledge?

Is what we think we know about cancer wrong? Or at least some major assumptions? Probably yes. Since the genome project allowed us to learn so much more about the human genome and perhaps as importantly or more so, bringing down the cost and increasing the speed of tests by many fold, advances are accelerating. They are now finding that all that “junk DNA” that supposedly had no purpose is very important and codes for non-coding RNA that doesn’t make proteins, but control the making of them and many other functions. However, other than the DNA studies, there have been many studies on a more macro level and primarily in petri dishes. This could be a big mistake.

Petri dishes basically create a two dimensional environment for the cancer cells to grow in. The Johns Hopkins Health Review describes research being done at Hopkins by Denis Wirtz on how cancer behaves when it is in a 3D format as it would be in the body.

Zig Zag Path

Cancer cells have been thought to take zigzag path when they move, almost a random pattern. (That isn’t because they used zig zags.) When Dr. Wirtz and his team put cancer cells in a 3D matrix that better replicates the environment in the body, the cancer cells behave very differently. They move in a straight line through the cells. In a petri dish they look flat and tend to adhere to the bottom and have problems moving. In the 3D environment, the cells were rounder and had long protrusions at each end. The proteins that predict is virulence were spread through the cell instead of mostly on the bottom of the cell. They didn’t stick to the bottom of the medium and move slowly. They moved rapidly through the medium and in straight lines.

Bad research and New Life for Drugs?

So a lot of what research has shown to be the behavior of cancers was just caused by the two dimensional environment of the petri dish. Dr. Wirtz thinks that a lot of the research has to be re-examined and possibly thrown out. Of course, other scientists aren’t too pleased with this. He also thinks that drug companies might want to reexamine some of the drugs that failed clinical trials. They might work very differently on cancer cells in a 3D environment.

Kenneth Yamada has also published some important papers on the need to investigate in a 3D environment. He is one of the most cited scientists and has published on a range of topics.

Problems to Solve

Using 3D matrices should help research, but there will be problems too. Scientists sometimes do things because they are easy even though they don’t replicate the in vivo environment. Petri dishes are easy. The problem is that electron microscopy works great in a dish, not so much in a 3D matrix. ┬áSame goes for other important research tools. That problem needs to be resolved.

Metastasis

Most research has been on tumor shrinkage. Why? Once again because it is easy to study and measure. But a big problem with cancer is metastasis, when the cancer spreads to other parts of the body. This is still poorly understood but very little research dollars are going toward this. We really need for more money to be put into metastasis research using 3D matrices.