Abstract LB-69: Novel WBC gene expression assay for prostate cancer detection.

Proceedings: AACR 104th Annual Meeting 2013; Apr 6-10, 2013; Washington, DC In recent studies, we showed that several oncogenes and cancer-associated genes and proteins are differentially expressed in phagocytic WBCs of tumor-bearing mice (colon, lung, melanoma, and prostate), compared to non-phagocytic WBCs from the same mice as well as to phagocytic WBCs obtained from non-tumor-bearing mice. Prompted by the translational potential of these findings, we carried out whole genome microarray analysis of total RNA samples isolated from peripheral blood phagocytic (macrophages and neutrophils) and nonphagocytic (T cells) WBCs of prostate cancer patients (n = 58) and blood donors (n = 36). Comparison of the genomic expression profiles of macrophages vs. T cells or neutrophils vs. T cells of these patients to those identified in blood donors revealed the presence of gene signatures that are unique to the patient population. These differentially expressed genes were used to generate receiver operating characteristic curves. The area under the curve was 1.000 for macrophages and 0.980 for neutrophils, indicating the high accuracy of the assay. While the PSA cutoff of 4 ng/mL failed to identify 14 of the 58 patients, the assay reported herein correctly identified 57 out of the 58 patients and all 36 controls (sensitivity = 0.983; specificity = 1.000) when macrophages were used; with neutrophils, there were 7 false negatives (sensitivity = 0.879; Specificity = 1.000). These promising results suggest that the approach lays the foundation for a next generation diagnostic blood test for prostate-cancer. Citation Format: Amin I. Kassis, Qi Wu, Maliackal Poulo Joy, Pichumani Balagurumoorthy, Massimo Loda, Carolyn Evan, Gillian Petrozziello, Philip W. Kantoff, S. James Adelstein. Novel WBC gene expression assay for prostate cancer detection. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr LB-69. doi:10.1158/1538-7445.AM2013-LB-69 Note: This abstract was not presented at the AACR Annual Meeting 2013 because the presenter was unable to attend.