THE "NEW" PROSTATE CANCER INFOLINK

A newly published paper in the journal called The Prostate has described a type of previously unidentified cell that may indicate the presence of a more aggressive subtype of prostate cancer.

This new paper by Sharpe et al. discusses what appears to be a prostate cancer-specific cell type that the authors have called prostate cancer syndecan-1 positive  or PCSP cells. It appears that these cells were only be found in the “stroma” of prostate tumors and in nearby normal prostate tissue. (The word “stroma” in this context means the surrounding and supporting anatomical and cellular structure of the tissues around the tumor.)

The authors report that these PCSP cells have the following characteristics:

• They express a previously recognized biochemical known as syndecan-1, which is a heparan sulfate proteoglycan, and which may have potential as biomarker for risk of prostate cancer (but studies of this possibility have not been conclusive to date).
• They do not show up (“co-stain”) with other common markers for prostate epithelial, stromal, or immune cell populations on standard histological staining.
• They “look different” to other types of prostate and prostate cancer cell under the microscope, in that they are often more elongated than the other cells around them and they have “prominent lamellipodia”. (A “lamellipodium” is a flattened extension of a cell, kind of equivalent to a “foot”, that helps it to stick to and move over other tissues.)
• They could be found in 20 to 25 percent of all prostate tumors evaluated (out of a total of 157 prostate cancer tumor and normal prostate tissue samples).
• They could not be found at all in non-diseased, normal prostate tissue.
• They were particularly evident in a subset of prostate cancer tissues that had a primary Gleason grade of 5 (i.e., tissues with Gleason scores of 5 + 5 = 10, 5 + 4 = 9, and 5+ 3 = 8).

Quite what this finding may mean in terms of the development and management of more aggressive forms of prostate cancer is not yet clear. These cells can only be identified by specialized, immunohistochemical analysis of a tumor specimen (from a biopsy sample or a surgical sample). However, as Sharpe et al. point out:

• The presence of the “prominent lamellipodia” implies that these cells have a relatively high ability to move (i.e., migrate) from their place of origin out into other tissues.
• This may have implications for the more rapid spread of more aggressive forms of prostate cancer.

More research will be needed to see if this cellular subtype is a critical factor in the metastatic potential of an initially localized prostate cancer.

Filed under: Diagnosis, Risk | Tagged: cell, histopathology, subtype, syndecan-1 |