Every so often we note that we still have little to no really clear idea why men get prostate cancer in the first place (or indeed why any of us get any type of cancer). In this context, some new research from a team at the University of California, Los Angeles, is at least interesting.
Their hypothesis is outlined in a paper by Liu et al. in the journal Cancer Reports, along with a media release from UCLA that you can find on the ScienceDaily web site.
What Liu et al. say is basically this:
- We know that inflammation of the prostate is a risk factor for prostate cancer, and particularly for the more aggressive types of prostate cancer.
- We haven’t known exactly why inflammation is a risk factor for prostate cancer.
- They have discovered a type of cell in the human prostate that is particularly susceptible to becoming cancerous.
- Prostate inflammation seems to increase the numbers of this type of cell that can be found in the prostate, and so …
- This may explain why prostate inflammation can increase risk for prostate cancer.
The type of cell they are talking about is a specific type of luminal cell that expresses a gene called CD38 at an unusually low level, so they are calling these cells CD38lo luminal cells, and they can often be found in and near to areas of the prostate that are inflamed. (Luminal cells are cells that line the interior of differing types of tube-like structure in many organs.)
Now there are all sorts of ways the prostate can become inflamed. Some are very evident (severe acute infection of the prostate; aggressive growth of the prostate because of benign prostatic hyperplasia; inflammation caused by calcification of prostate tissue) but many of us may just have rather mild forms of chronic inflammation that, nonetheless, might stimulate an increase in numbers of CD38lo luminal cells at a point in time, and development of clinically evident prostate cancer as a consequence could take many years to develop after such an event.
The idea that certain types of cell in the prostate might have a higher risk for becoming cancerous than others has been around for a while. Furthermore, earlier work had suggested that the cells that might be associated with initiation of prostate cancer might well be luminal cells (see, for example, this study by Wang et al.) What the researchers at UCLA have been able to do is show that they could identify a very specific type of luminal cell that might exhibit such an effect under appropriate circumstances.
Could this hypothesis explain every case of prostate cancer? Probably not. But it might be able to explain an awful lot of them — if this hypothesis can be confirmed through further research.
If this hypothesis is correct, could it help us to develop methods to lower risk for prostate cancer? Al we can say about that at this point in time is probably, “Maybe.”
Filed under: Risk | Tagged: CD38, cell, inflammation, luminal, risk |
THE "NEW" PROSTATE CANCER INFOLINK 
As an adult, every time I had a urine analysis there would be a few red blood cells in my urine, I was given Cipro and that was that. In a couple of years, the same thing would happen. I had a full work up for this and all GU systems were ok. Finally I got aggressive prostate cancer. This low level inflammation should be a warning sign. If this scenario could be dealt with successfully initially, we would eliminate quite a few prostate cancer diagnoses.
Dear Harrison:
The problem, however, is that there are many different reasons for such inflammations. “Dealing with them successfully” up front is actually a rather challenging proposition, and there is no guarantee that the patient might still not get prostate cancer.
It seems logical that inflammation may be a risk factor for prostate cancer. But I recalled another paper which indicated that inflammation may be an lower risk for prostate cancer. I was able to find it in some old files. So not sure what all this means.
As a separate comment. Do you know of a web site or paper that reviews all of the different types of imaging (3T MRI, PET scans, etc.) and provides general information on the pros/cons and uses.
Dear John:
(1) What the authors of the paper you refer to actually found was not that inflammation reduced risk for prostate cancer but rather that patients who had negative prostate biopsies that had markers of inflammation were less likely to be diagnosed with prostate cancer in a subsequent prostate biopsy. There is subtle but important distinction here. They go on to point out that this may be because they are managed differently by their physicians (on the presumption that they “only” have an inflammation).
(2) No, I know of no really good comparative review of all of the varied types of scanning technique that are now being used in the diagnosis, work-up, and monitoring of prostate cancer. Part of the problem is that this field is moving so fast that almost any review risks being out of date by the time it is published.