David Turay

Plasma-Derived Exosomal Survivin, a Plausible Biomarker for Early Detection of Prostate Cancer

Background Survivin is expressed in prostate cancer (PCa), and its downregulation sensitizes PCa cells to chemotherapeutic agents in vitro and in vivo. Small membrane-bound vesicles called exosomes, secreted from the endosomal membrane compartment, contain RNA and protein that they readily transport via exosome internalization into recipient cells. Recent progress has shown that tumor-derived exosomes play multiple roles in tumor growth and metastasis and may produce these functions via immune escape, tumor invasion and angiogenesis. Furthermore, exosome analysis may provide novel biomarkers to diagnose or monitor PCa treatment. Methods Exosomes were purified from the plasma and serum from 39 PCa patients, 20 BPH patients, 8 prostate cancer recurrent and 16 healthy controls using ultracentrifugation and their quantities and qualities were quantified and visualized from both the plasma and the purified exosomes using ELISA and Western blotting, respectively. Results Survivin was significantly increased in the tumor-derived samples, compared to those from BPH and controls with virtually no difference in the quantity of Survivin detected in exosomes collected from newly diagnosed patients exhibiting low (six) or high (nine) Gleason scores. Exosome Survivin levels were also higher in patients that had relapsed on chemotherapy compared to controls. Conclusions These studies demonstrate that Survivin exists in plasma exosomes from both normal, BPH and PCa subjects. The relative amounts of exosomal Survivin in PCa plasma was significantly higher than in those with pre-inflammatory BPH and control plasma. This differential expression of exosomal Survivin was seen with both newly diagnosed and advanced PCa subjects with high or low-grade cancers. Analysis of plasma exosomal Survivin levels may offer a convenient tool for diagnosing or monitoring PCa and may, as it is elevated in low as well as high Gleason scored samples, be used for early detection.

The AAST prospective Aortic Occlusion for Resuscitation in Trauma and Acute Care Surgery (AORTA) registry: Data on contemporary utilization and outcomes of aortic occlusion and resuscitative balloon occlusion of the aorta (REBOA)

INTRODUCTION Aortic occlusion (AO) for resuscitation in traumatic shock remains controversial. Resuscitative endovascular balloon occlusion of the aorta (REBOA) offers an emerging alternative. METHODS The American Association for the Surgery of Trauma Aortic Occlusion for Resuscitation in Trauma and Acute Care Surgery registry prospectively identified trauma patients requiring AO from eight ACS Level 1 centers. Presentation, intervention, and outcome variables were collected and analyzed to compare REBOA and open AO. RESULTS From November 2013 to February 2015, 114 AO patients were captured (REBOA, 46; open AO, 68); 80.7% were male, and 62.3% were blunt injured. Aortic occlusion occurred in the emergency department (73.7%) or the operating room (26.3%). Hemodynamic improvement after AO was observed in 62.3% [REBOA, 67.4%; open OA, 61.8%); 36.0% achieving stability (systolic blood pressure consistently >90 mm Hg, >5 minutes); REBOA, 22 of 46 (47.8%); open OA, 19 of 68 (27.9%); p =0.014]. Resuscitative endovascular balloon occlusion of the aorta (REBOA) access was femoral cut-down (50%); US guided (10.9%) and percutaneous without imaging (28.3%). Deployment was achieved in Zones I (78.6%), II (2.4%), and III (19.0%). A second AO attempt was required in 9.6% [REBOA, 2 of 46 (4.3%); open OA, 9 of 68 (13.2%)]. Complications of REBOA were uncommon (pseudoaneurysm, 2.1%; embolism, 4.3%; limb ischemia, 0%). There was no difference in time to successful AO between REBOA and open procedures (REBOA, 6.6 ± 5.6 minutes; open OA, 7.2 ± 15.1; p = 0.842). Overall survival was 21.1% (24 of 114), with no significant difference between REBOA and open AO with regard to mortality [REBOA, 28.2% (13 of 46); open OA, 16.1% (11 of 68); p = 0.120]. CONCLUSION Resuscitative endovascular balloon occlusion of the aorta has emerged as a viable alternative to open AO in centers that have developed this capability. Further maturation of the American Association for the Surgery of Trauma Aortic Occlusion for Resuscitation in Trauma and Acute Care Surgery database is required to better elucidate optimal indications and outcomes. LEVEL OF EVIDENCE Therapeutic/care management study, level IV.

Early diagnostic value of survivin and its alternative splice variants in breast cancer.

BackgroundThe inhibitor of apoptosis (IAP) protein Survivin and its splice variants are differentially expressed in breast cancer tissues. Our previous work showed Survivin is released from tumor cells via small membrane-bound vesicles called exosomes. We, therefore, hypothesize that analysis of serum exosomal Survivin and its splice variants may provide a novel biomarker for early diagnosis of breast cancer.MethodsWe collected sera from forty breast cancer patients and ten control patients who were disease free for 5 years after treatment. In addition, twenty-three paired breast cancer tumor tissues from those same 40 patients were analyzed for splice variants. Serum levels of Survivin were analyzed using ELISA and exosomes were isolated from this serum using the commercially available ExoQuick kit, with subsequent Western blots and immunohistochemistry performed.ResultsSurvivin levels were significantly higher in all the breast cancer samples compared to controls (p < 0.05) with exosome amounts significantly higher in cancer patient sera compared to controls (p < 0.01). While Survivin and Survivin-∆Ex3 splice variant expression and localization was identical in serum exosomes, differential expression of Survivin-2B protein existed in the exosomes. Similarly, Survivin and Survivin-∆Ex3 proteins were the predominant forms detected in all of the breast cancer tissues evaluated in this study, whereas a more variable expression of Survivin-2B level was found at different cancer stages.ConclusionIn this study we show for the first time that like Survivin, the Survivin splice variants are also exosomally packaged in the breast cancer patients’ sera, mimicking the survivin splice variant pattern that we also report in breast cancer tissues. Differential expression of exosomal-Survivin, particularly Survivin-2B, may serve as a diagnostic and/or prognostic marker, a “liquid biopsy” if you will, in early breast cancer patients. Furthermore, a more thorough understanding of the role of this prominent antiapoptotic pathway could lead to the development of potential therapeutics for breast cancer patients.

Proteomic Profiling of Serum-Derived Exosomes from Ethnically Diverse Prostate Cancer Patients

ABSTRACT Prostate cancer (PCa) remains the most frequently diagnosed male malignancy in Western countries and the second most common cause of male cancer death in the United States. The relatively elevated PCa incidence and mortality among African American men makes this cancer type a challenging health disparity disease. To increase the chance for successful trea tment, earlier detection and prediction of tumor aggress iveness will be important and need to be resolved. This study demonstrates that small membrane-bound vesicles shed from the tumor called exosomes contain ethnically and tumor-specific biomarkers, and could be exploited for their diagnostic and therapeutic potential.

Prospective derivation of a clinical decision rule for thoracolumbar spine evaluation after blunt trauma: An American Association for the Surgery of Trauma Multi-Institutional Trials Group Study.

BACKGROUND Unlike the cervical spine (C-spine), where National Emergency X-Radiography Utilization Study (NEXUS) and the Canadian C-spine Rules can be used, evidence-based thoracolumbar spine (TL-spine) clearance guidelines do not exist. The aim of this study was to develop a clinical decision rule for evaluating the TL-spine after injury. METHODS Adult (≥15 years) blunt trauma patients were prospectively enrolled at 13 US trauma centers (January 2012 to January 2014). Exclusion criteria included the following: C-spine injury with neurologic deficit, preexisting paraplegia/tetraplegia, and unevaluable examination. Remaining evaluable patients underwent TL-spine imaging and were followed up to discharge. The primary end point was a clinically significant TL-spine injury requiring TL-spine orthoses or surgical stabilization. Regression techniques were used to develop a clinical decision rule. Decision rule performance in identifying clinically significant fractures was tested. RESULTS Of 12,479 patients screened, 3,065 (24.6%) met inclusion criteria (mean [SD] age, 43.5 [19.8] years [range, 15–103 years]; male sex, 66.3%; mean [SD] Injury Severity Score [ISS], 8.8 [7.5]). The majority underwent computed tomography (93.3%), 6.3% only plain films, and 0.2% magnetic resonance imaging exclusively. TL-spine injury was identified in 499 patients (16.3%), of which 264 (8.6%) were clinically significant (29.2% surgery, 70.8% TL-spine orthosis). The majority was AO Type A1 282 (56.5%), followed by 67 (13.4%) A3, 43 (8.6%) B2, and 32 (6.4%) A4 injuries. The predictive ability of clinical examination (pain, midline tenderness, deformity, neurologic deficit), age, and mechanism was examined; positive clinical examination finding resulted in a sensitivity of 78.4% and a specificity of 72.9%. Addition of age of 60 years or older and high-risk mechanism (fall, crush, motor vehicle crash with ejection/rollover, unenclosed vehicle crash, auto vs. pedestrian) increased sensitivity to 98.9% with specificity of 29.0% for clinically significant injuries and 100.0% sensitivity and 27.3% specificity for injuries requiring surgery. CONCLUSION Clinical examination alone is insufficient for determining the need for imaging in evaluable patients at risk of TL-spine injury. Addition of age and high-risk mechanism results in a clinical decision-making rule with a sensitivity of 98.9% for clinically significant injuries. LEVEL OF EVIDENCE Diagnostic test, level III.

Localization and upregulation of survivin in cancer health disparities: a clinical perspective

Survivin is one of the most important members of the inhibitors of apoptosis protein family, as it is expressed in most human cancers but is absent in normal, differentiated tissues. Lending to its importance, survivin has proven associations with apoptosis and cell cycle control, and has more recently been shown to modulate the tumor microenvironment and immune evasion as a result of its extracellular localization. Upregulation of survivin has been found in many cancers including breast, prostate, pancreatic, and hematological malignancies, and it may prove to be associated with the advanced presentation, poorer prognosis, and lower survival rates observed in ethnically diverse populations.

Differential protein expression in exosomal samples taken from trauma patients

Traumatic brain injuries (TBI) are among the most misdiagnosed and underreported types of head trauma. The potential long‐term impact of undiagnosed or incorrectly identified concussions and other head injuries are potentially devastating, as evidenced by the increasing societal burden exhibited by soldiers returning from combat and athletes in contact sports. Concussions and TBI are notoriously difficult to correctly diagnose and prognosis for these injuries is poorly understood. In order to increase the likelihood of successful diagnosis, treatment, and prediction of outcomes, a definitive differential diagnosis will need to be established. The establishment of a “trauma–specific profile” or a panel of known trauma markers will significantly aid in this goal. Small membrane vesicles called exosomes have been shown to contain proteins and injury‐specific biomarkers. In the future it is possible that they could become an important tool, utilized for their diagnostic and therapeutic potential.

Multi-institutional, prospective, observational study comparing the Gastrografin challenge versus standard treatment in adhesive small bowel obstruction

INTRODUCTION Existing trials studying the use of Gastrografin for management of adhesive small bowel obstruction (SBO) are limited by methodological flaws and small sample sizes. We compared institutional protocols with and without Gastrografin (GG), hypothesizing that a SBO management protocol utilizing GG is associated with lesser rates of exploration, shorter length of stay, and fewer complications. METHODS A multi-institutional, prospective, observational study was performed on patients appropriate for GG with adhesive SBO. Exclusion criteria were internal/external hernia, signs of strangulation, history of abdominal/pelvic malignancy, or exploration within the past 6 weeks. Patients receiving GG were compared to patients receiving standard care without GG. RESULTS Overall, 316 patients were included (58 ± 18 years; 53% male). There were 173 (55%) patients in the GG group (of whom 118 [75%] successfully passed) and 143 patients in the non-GG group. There were no differences in duration of obstipation (1.6 vs. 1.9 days, p = 0.77) or small bowel feces sign (32.9% vs. 25.0%, p = 0.14). Fewer patients in the GG protocol cohort had mesenteric edema on CT (16.3% vs. 29.9%; p = 0.009). There was a lower rate of bowel resection (6.9% vs. 21.0%, p < 0.001) and exploration rate in the GG group (20.8% vs. 44.1%, p < 0.0001). GG patients had a shorter duration of hospital stay (4 IQR 2–7 vs. 5 days IQR 2–12; p = 0.036) and a similar rate of complications (12.5% vs. 17.9%; p = 0.20). Multivariable analysis revealed that GG was independently associated with successful nonoperative management. CONCLUSION Patients receiving Gastrografin for adhesive SBO had lower rates of exploration and shorter hospital length of stay compared to patients who did not receive GG. Adequately powered and well-designed randomized trials are required to confirm these findings and establish causality. LEVEL OF EVIDENCE Therapeutic, level III.

Early diagnostic value of survivin and its alternative splice variants in breast cancers.

35 Background: The inhibitor of apoptosis (IAP) protein Survivin and its splice variants are differentially expressed in breast cancer tissues and have recently been shown to be released from tumor cells via small membrane-bound vesicles called exosomes. Tumor-derived exosomes play multiple roles in tumor growth and metastasis and may produce these functions by impacting immune escape, tumor invasion and angiogenesis. We, therefore, hypothesize that analysis of exosomal Survivin and its splice variants may provide a novel biomarker for early diagnosis of breast cancer in addition to current recommended methods. METHODS Twenty paired breast cancer patients sera and tumor tissue, and ten normal control sera were used for analysis. ELISA was performed to quantitate serum levels of Survivin. Exosomes were isolated from the sera using Exoquick. RT-PCR, western blots with densitometry, and immunohistochemistry followed by confocal microscopy were then performed. RESULTS For each breast cancer patient serum, Survivin levels were significantly higher compared to control (p<0.05). While Survivin and the DEx3 splice variant expression and localization were similar, differential expression of Survivin and the 2B splice variant protein and mRNA existed in the exosomes and tissue samples. Survivin and -DEx3 proteins were the predominant forms detected in 100% (20/20) of the breast cancer tissues evaluated, whereas a more variable expression of Survivin-2B, with enhanced levels found in areas of necrosis. We also for the first time here show the exosomal localization of Survivin and its splice variants DEx3 and 2B in sera from breast cancer patients. CONCLUSIONS The result of the proposed project supports our hypothesis that differential expression of exosomal-Survivin and its alternative splice variants may serve as a diagnostic marker in breast cancer patients. For future direction, we plan to study the prognostic value of exosomal-Survivin and its splice variants on a large panel of primary breast cancers within a setting of well-followed clinical outcomes.

Stapled versus hand-sewn: A prospective emergency surgery study. An American Association for the Surgery of Trauma multi-institutional study

BACKGROUND Data from the trauma patient population suggests handsewn (HS) anastomoses are superior to stapled (ST). A recent retrospective study in emergency general surgery (EGS) patients had similar findings. The aim of the current study was to evaluate HS and ST anastomoses in EGS patients undergoing urgent/emergent operations. METHODS The study was sponsored by the American Association for the Surgery of Trauma Multi-Institutional Studies Committee. Patients undergoing urgent/emergent bowel resection for EGS pathology were prospectively enrolled from July 22, 2013 to December 31, 2015. Patients were grouped by HS/ST anastomoses, and variables were collected. The primary outcome was anastomotic failure. Similar to other studies, anastomotic failure was evaluated at the anastomosis level. Multivariable logistic regression was performed controlling for age and risk factors for anastomotic failure. RESULTS Fifteen institutions enrolled a total of 595 patients with 649 anastomoses (253 HS and 396 ST). Mean age was 61 years, 51% were men, 7% overall mortality. Age and sex were the same between groups. The overall anastomotic failure rate was 12.5%. The HS group had higher lactate, lower albumin, and were more likely to be on vasopressors. Hospital and intensive care unit days, as well as mortality, were greater in the HS group. Anastomotic failure rates and operative time were equivalent for HS and ST. On multivariate regression, the presence of contamination at initial resection (odds ratio, 1.965; 95% confidence interval, 1.183–3.264) and the patient being managed with open abdomen (odds ratio, 2.529; 95% confidence interval, 1.492–4.286) were independently associated with anastomotic failure, while the type of anastomosis was not. CONCLUSION EGS patients requiring bowel resection and anastomosis are at high risk for anastomotic failure. The current study illustrates an apparent bias among acute care surgeons to perform HS techniques in higher-risk patients. Despite the individualized application of technique for differing patient populations, the risk of anastomotic failure was equivalent when comparing HS and ST anastomoses. LEVEL OF EVIDENCE Therapeutic study, level II.