Development of a Sampling and Storage Protocol of Extracellular Vesicles (EVs)-Establishment of the First EV Biobank for Polytraumatized Patients.

In the last few years, several studies have emphasized the existence of injury-specific EV "barcodes" that could have significant importance for the precise diagnosis of different organ injuries in polytrauma patients. To expand the research potential of the NTF (network trauma research) biobank of polytraumatized patients, the NTF research group decided to further establish a biobank for EVs. However, until now, the protocols for the isolation, characterization, and storage of EVs for biobank purposes have not been conceptualized. Plasma and serum samples from healthy volunteers (n = 10) were used. Three EV isolation methods of high relevance for the work with patients' samples (ultracentrifugation, size exclusion chromatography, and immune magnetic bead-based isolation) were compared. EVs were quantified using nanoparticle tracking analysis, EV proteins, and miRNAs. The effects of different isolation solutions; the long storage of samples (up to 3 years); and the sensibility of EVs to serial freezing-thawing cycles and different storage conditions (RT, 4/-20/-80 °C, dry ice) were evaluated. The SEC isolation method was considered the most suitable for EV biobanking. We did not find any difference in the quantity of EVs between serum and plasma-EVs. The importance of particle-free PBS as an isolation solution was confirmed. Plasma that has been frozen for a long time can also be used as a source of EVs. Serial freezing-thawing cycles were found to affect the mean size of EVs but not their amount. The storage of EV samples for 5 days on dry ice significantly reduced the EV protein concentration.

Evaluation of New Cardiac Damage Biomarkers in Polytrauma: GDF-15, HFABP and uPAR for Predicting Patient Outcomes.

Background: Polytrauma is one of the leading mortality factors in younger patients, and in particular, the presence of cardiac damage correlates with a poor prognosis. Currently, troponin T is the gold standard, although troponin is limited as a biomarker. Therefore, there is a need for new biomarkers of cardiac damage early after trauma. Methods: Polytraumatized patients (ISS ≥ 16) were divided into two groups: those with cardiac damage (troponin T > 50 pg/mL, n = 37) and those without cardiac damage (troponin T < 12 pg/mL, n = 32) on admission to the hospital. Patients' plasma was collected in the emergency room 24 h after trauma, and plasma from healthy volunteers (n = 10) was sampled. The plasma was analyzed for the expression of HFABP, GDF-15 and uPAR proteins, as well as miR-21, miR-29, miR-34, miR-122, miR-125b, miR-133, miR-194, miR-204, and miR-155. Results were correlated with patients' outcomes. Results: HFABP, uPAR, and GDF-15 were increased in polytraumatized patients with cardiac damage (p < 0.001) with a need for catecholamines. HFABP was increased in non-survivors. Analysis of systemic miRNA concentrations showed a significant increase in miR-133 (p < 0.01) and miR-21 (p < 0.05) in patients with cardiac damage. Conclusion: All tested plasma proteins, miR-133, and miR-21 were found to reflect the cardiac damage in polytrauma patients. GDF-15 and HFABP were shown to strongly correlate with patients' outcomes.

Transglutaminase 2 is associated with adverse colorectal cancer survival and represents a therapeutic target.

Molecular markers for predicting prognosis of colorectal cancer (CRC) patients are urgently needed for effective disease management. We reported previously that the multifunctional enzyme Transglutaminase 2 (TGM2) is essential for CRC cell survival by inactivation of the tumor suppressor p53. Based on these data, we determined the clinical relevance of TGM2 expression and explored its potential as prognostic marker and therapeutic target in CRC. We profiled TGM2 protein expression in tumor samples of 279 clinically characterized CRC patients using immunohistochemical staining. TGM2 expression was upregulated in matched tumor samples in comparison to normal tissue. A strong TGM2 expression was associated with advanced tumor stages and predicted worse prognosis regarding progression-free and overall-survival, even at early stages. Inhibition of TGM2 in CRC cell lines by the inhibitors LDN27219 and Tyrphostin resulted in a strong reduction of cancer cell proliferation and tumorsphere formation in vitro by induction of p53-mediated apoptosis. Primary patient-derived tumorsphere formation was significantly reduced by inhibition of TGM2. Treatment of mice with TGM2 inhibitors exhibited a significant deceleration of tumor progression. Our data indicate that high TGM2 expression in CRC is associated with worse prognosis and may serve as a therapeutic target in CRC patients with strong TGM2 expression.

Ligustrazine Suppresses the Growth of HRPC Cells through the Inhibition of Cap- Dependent Translation Via Both the mTOR and the MEK/ERK Pathways.

Ligustrazine (TMP) has recently been used for the treatment of various cancers. However, its exact mechanisms of action, particularly the functions and the mechanisms of Ligustrazine in human hormone-refractory prostate cancer (HRPC), have not yet been extensively studied. Recently, our findings suggest that Ligustrazine dose- and time-dependently inhibits the growth of HRPC cells by reducing their proliferation and promoting apoptosis. Interestingly, the treatment of hormone-refractory prostate cancer (PC-3) cells with Ligustrazine results in a significant inhibition of the activation of mTOR and related downstream targets, which are critical for cell growth. Furthermore, pull-down assays with 7-methyl- GTP Sepharose 4B beads indicate that Ligustrazine reduces the available eIF4E for translation initiation. Accordingly, the results from the translation assay using a luciferase reporter system further demonstrate that Ligustrazine indeed inhibits cap-dependent translation. In addition, the transient overexpression of eIF4E or MNK1 prevents the Ligustrazine-induced inhibition of proliferation and confers significant protection against Ligustrazine-induced apoptosis. Therefore, the present study provides evidences that Ligustrazine may be a candidate for therapeutic reagent for the treatment of HRPC and certifies that Ligustrazine modulates the availability of eIF4E mainly through the mTOR and MEK/ERK signaling pathways to inhibit cap-dependent translation. Taken together, our results indicate that the inhibition of cap-dependent translation is likely an essential mechanism in Ligustrazine-induced apoptosis.