Circulating PSA-containing macrophages as a possible target for the detection of prostate cancer: a
Math P G Leers1, Marius Nap, Ralf Herwig
1Departments of Clinical Chemistry and Hematology, Atrium Medical Center Parkstad, Heerlen, Netherlands.
Abstract:
A major problem of serum prostate-specific antigen (PSA) for predicting prostate cancer risk is diagnostic uncertainty. To detect circulating macrophages with phagocytized fragments (eg, PSA) of prostate tumor cells and determine if the number of circulating PSA-containing macrophages can help differentiate between benign and malignant prostate disease, we collected mononuclear cells from peripheral blood. After labeling the macrophages, phagocytized PSA was detected by incubating the cells with a phycoerythrin-conjugated PSA monoclonal antibody. Flow cytometric analysis was performed. A significant difference was observed in the mean+/-SD percentage of activated macrophages (CD14+/CD16+) between malignant (28.8%+/-13.0%) and benign conditions (17.3%+/-6.8%; P< .0001). A significant increase was detected in the percentage of PSA-containing macrophages in prostate cancer (17.7%+/-12.3%) vs benign disorders (3.6%+/-1.9%; P< .0001) and between localized (10.5%+/-3.4%) and metastasized prostate carcinoma (26.3%+/-14.3%; P= .0002). The new method for detecting circulating PSA-containing macrophages can be suitable for differentiating prostate cancer from benign conditions and, possibly, low-risk from more aggressive prostate cancer.
Insights
Detecting prostate cancer is challenging. A new method identifies PSA-containing macrophages in blood, helping distinguish between benign and malignant prostate disease and potentially grading cancer aggressiveness.
Area of Science:
- Urology
- Immunology
- Oncology
Background:
- Serum prostate-specific antigen (PSA) levels present diagnostic uncertainty in prostate cancer risk prediction.
- Distinguishing between benign and malignant prostate conditions requires improved diagnostic markers.
Purpose of the Study:
- To detect circulating macrophages containing prostate tumor cell fragments (PSA).
- To determine if PSA-containing macrophages can differentiate benign from malignant prostate disease.
- To assess if this method can help differentiate localized from metastatic prostate cancer.
Main Methods:
- Mononuclear cells were isolated from peripheral blood.
- Macrophages were labeled, and phagocytized PSA was detected using a phycoerythrin-conjugated PSA monoclonal antibody.
- Flow cytometry was employed for analysis of activated and PSA-containing macrophages.
Main Results:
- A significant difference in activated macrophages (CD14+/CD16+) was observed between malignant (28.8%) and benign (17.3%) conditions (P < .0001).
- PSA-containing macrophages were significantly increased in prostate cancer (17.7%) versus benign disorders (3.6%) (P < .0001).
- A significant increase was noted in PSA-containing macrophages between localized (10.5%) and metastatic prostate cancer (26.3%) (P = .0002).
Conclusions:
- The detection of circulating PSA-containing macrophages offers a promising method for differentiating prostate cancer from benign conditions.
- This approach may also aid in distinguishing between low-risk and more aggressive prostate cancer.
- This novel method enhances diagnostic accuracy for prostate cancer.
