Transcriptome profiling of whole blood cells identifies PLEK2 and C1QB in human melanoma.

Background: Developing analytical methodologies to identify biomarkers in easily accessible body fluids is highly valuable for the early diagnosis and management of cancer patients. Peripheral whole blood is a "nucleic acid-rich" and "inflammatory cell-rich" information reservoir and represents systemic processes altered by the presence of cancer cells.

Methodology/principal Findings: We conducted transcriptome profiling of whole blood cells from melanoma patients.

Limited dynamic range of immune response gene expression observed in healthy blood donors using RT-PCR.

The use of quantitative gene expression analysis for the diagnosis, prognosis, and monitoring of disease requires the ability to distinguish pathophysiological changes from natural variations. To characterize these variations in apparently healthy subjects, quantitative real-time PCR was used to measure various immune response genes in whole blood collected from blood bank donors. In a single-time-point study of 131 donors, of 48 target genes, 43 were consistently expressed and 34 followed approximately log-normal distribution.

Mice lacking tissue plasminogen activator and urokinase plasminogen activator genes show attenuated matrix metalloproteases activity after sciatic nerve crush.

Plasminogen activators (PAs), tissue PA (tPA) and urokinase PA (uPA), have been shown to be induced in sensory neurons after sciatic nerve crush. These findings suggested that PAs facilitate peripheral nerve regeneration by digesting adhesive cell contacts and by activation of other proteases, thereby initiating a proteolytic cascade. Both tPA and uPA activate some matrix metalloproteases (MMPs), indirectly via plasminogen activation or directly, such as the uPA activation of MMP-2.