At a meeting of some leading members of the prostate cancer advocacy community yesterday morning, during the ASCO meeting in Orlando, Dr. William Simons of the Prostate Cancer Foundation distributed a diagram suggesting that there may be as many as 15-18 different sub-types of prostate cancer.
It has long been known that not all prostate cancers are the same. At the very simplest level we have been aware that there are indolent and aggressive prostate cancers; there are hormone-responsive and hormone-non-responsive prostate cancers; there are prostate cancers with high and low Gleason scores; etc.
However, what the Prostate Cancer Foundation, working with its broad team of scientific researchers, has now been able to do is look at prostate cancer much more from the point of view of the molecular development of the differing sub-types of this cancer, the molecular targets that can be blocked or stimulated to have particular therapeutic effects, and the specific ways in which the treatments that are known to be effective impact specific molecular targets:
- The drugs like the LHRH agonists and the antiandrogens impact the androgen receptors.
- Drugs like abiraterone actetate also impact the androgen receptors, but in a rather different way.
- Docetaxel affects β-tubulin and can therefore interrupt cancer cell development.
However, there are still at least a dozen other, different pathways that may be particularly important in managing certain subtypes of prostate cancer, and we are only just beginning to appreciate how, when a patients can be shown to have a high level of experssion of certain enzymes or prostein associated with their prostate cancer subtype, we may been to be able to block or or more specific molecular pathways in order to control (or perhaps stop) the developmentof that specific prostate cancer subtype.
The good thing, however, is that we really are making progress in understanding more about the details of how prostate cancer develops and progresses. Such progress is critical to the development of the next generations of products designed to treat and (better still) to prevent prostate cancer, with greater effectiveness and safety than anything we have available today.