1. I assume the reader knows what breast cancer is.
2. Taxol (also known as paclitaxel) is a chemical compound, a drug that is effective in treating breast cancer. It can be found and isolated from the bark of the pacific yew tree Taxus Brevifolia. Bristol Myers Squibb once held the patent rights of Taxol, but I believe their rights are now expired. The National Institute of Health has a page for Taxol.
3. Here's the problem: there are not enough yew trees to supply enough Taxol to treat all the cancer patients. Even if there are enough trees, the monetary cost of the drug could be prohibitively high. And even if the cost if affordable, how do we replenish all the trees once we use them up? Taxus Brevefolia takes a long time (20 yrs) to mature.
4. There was an attempt to solve this problem: to synthesize Taxol by chemical means rather than to isolate it from the tree. In order to be able to this, the scientists need to know the molecular formula (structure) of Taxol in order to design a synthetic pathway.
5. We know the molecular formula of Taxol. It was solved by Mansukh Wani and Monroe Wall from the Research Triangle Institute in North Carolina. It was painstaking work, and the formula is shown.
6. In the 90s, research groups around the world have tried and succeeded in making Taxol. However, after spending tens of millions of dollars, they could only make miligram quantities. The public needs hundreds of grams or kilograms of Taxol.
7. It is very difficult to scale-up a miligram production system to a kilogram system. As an analogy, if you can make a one-foot diameter pizza, would you be able to easily make a one-thousand-feet diameter pizza? Even if your oven is that big, there are other complications: the middle of the pizza will be undercooked, while the side will be overcooked.
8. I write this post to highlight the following point: it is one challenge to discover a cure, it is another challenge to manufacture kilograms of material once the cure has been discovered. Life is difficult (and therefore meaningful) for scientists.
9. The first challenge is tackled by a multidiscplinary group of chemists, biochemists, pharmacists, medical doctors, biologists, etc. The second challenge is tackled by chemists, chemical engineers, mechanical engineers, etc. Collaboration is important, and funding is also important. If the task is undertaken by a private company, then profitability is an important factor.
10. Back to breast cancer. So what are we going to do about it? I'm not an expert on cancer, I'm not an MD. If you suspect that you or somebody you know have breast cancer, please seek advice from a physician. If you would like to know more about breast cancer, a good place to start is the Susan Komen site.
11. Back to Taxol. There are small companies out there growing Taxus aggresively to produce more Taxol. The supply challenge continues to be tackled. Besides the technical challenges, these companies have to deal with profitablitiy issues as well. One such company is Natural Pharmaceuticals Inc., which I'm not affiliated to in any way.
12. Curing cancer is not an easy task. At least now you know some of the challenges faced by the scientist working in this area.
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