TMPRSS2-ERG fusions confer efficacy of enzalutamide in an in vivo bone tumor growth model.

BACKGROUND: Castrate Resistant Prostate Cancer (CRPC) is an advanced disease resistant to systemic traditional medical or surgical castration, and resistance is primarily attributed to reactivation of AR through multiple mechanisms. TMPRSS2-ERG fusions have been shown to regulate AR signaling, interfere with pro-differentiation functions, and mediate oncogenic signaling. We have recently shown that ERG regulates intra-tumoral androgen synthesis and thereby facilitates AR function in prostate cancer cells. We hypothesize that enzalutamide treatment will be more effective in cells/tumors with TMPRSS2-ERG translocations because these tumors have increased AR signaling. METHODS: ERG knockdown was performed with VCaP cells using lentiviral infections to generate VCaP ERGshRNA cells and control VCaP scr cells with scrambled shRNA. Cell-growth analysis was performed to determine the effect of enzalutamide. Reverse transcription, quantitative real-time PCR (RT-qPCR) was used to determine the expression of AR responsive genes. Luciferase tagged VCaP scr and shRNA infected cells were used in an intra-tibial animal model for bone tumor growth analysis and enzalutamide treatment used to inhibit AR signaling in bone tumors. Western blotting analyzed VCaP bone tumor samples for ERG, AR, AKR1C3 and HSD3B1 and HSD3B2 expression. RESULTS: Enzalutamide inhibited the growth of VCaP scr cells more effectively than shERG cells. Analysis of AR responsive genes shows that Enzalutamide treatment at 5 micromolar concentration inhibited by 85-90% in VCaP Scr cells whereas these genes were inhibited to a lesser extent in VCaP shERG cells. Enzalutamide treatment resulted in severe growth inhibition in VCaP scr shRNA cells compared to VCaP shERG cells. In bone tumor growth experiment, VCaP ERG shRNA cells grew at slower than VCaP scr shRNA cells. Androgen biosynthetic enzyme expression is lower VCaP shERG bone tumors compared to VCaP scr shRNA bone tumors and enzalutamide inhibited the enzyme expression in both types of tumors. CONCLUSIONS: These data suggest that ERG transcription factor regulates androgen biosynthetic enzyme expression that enzalutamide treatment is more effective against VCaP bone tumors with an intact ERG expression, and that knocking down ERG in VCaP cells leads to a lesser response to enzalutamide therapy. Thus, ERG expression status in tumors could help stratify patients for enzalutamide therapy.

Risk factors for biochemical recurrence following radical perineal prostatectomy in a large contemporary series: a detailed assessment of margin extent and location.

OBJECTIVES: The implications of positive surgical margin (PSM) extent and location during radical perineal prostatectomy (RPP) have not been assessed in a contemporary series. We aimed to examine the incidence, location, and extent of PSM as well as their impact on biochemical recurrence (BCR) following RPP. MATERIALS AND METHODS: A total of 794 patients underwent RPP by a single surgeon between June 1993 and August 2010. Covariates included age, pathologic T stage, pathologic Gleason sum, preoperative PSA, prostate volume, PSM extent, and location. Life table, Kaplan-Meier, and Cox regression analyses assessed predictors of BCR following RPP. RESULTS: PSM were recorded in 162 patients (20.4%); of these, 83 (51.2%) were focal (≤ 1 mm) whereas 79 (48.8%) were broad (>1 mm). Location of PSM was anterior 10.5%, posterior or lateral 14.8%, bladder neck 23.5%, apical 32.1%, and multifocal 19.1%. At a median follow-up of 54 months, the 5-year BCR-free probability was 90.8% in patients with negative margins, 77.5% in patients with focal PSM, and 47.5% in patients with broad PSM. On multivariable analyses adjusted for age, pathologic T stage, pathologic Gleason sum, preoperative PSA, and prostate volume, broad PSM, (HR = 3.49, P < 0.001) as well as anterior (HR = 3.77, P = 0.003), bladder neck (HR = 2.25, P = 0.01) and multifocal (HR = 3.55, P < 0.001) PSM were independent predictors of BCR. CONCLUSIONS: In this study, we present oncologic outcomes following RPP in a large contemporary cohort of patients undergoing RPP. In adjusted analyses, broad and anterior PSM carried the highest risk of recurrence after RPP.

Robotic ultrasound probe for tumor identification in robotic partial nephrectomy: Initial series and outcomes.

OBJECTIVES: Accurate tumor identification during partial nephrectomy is essential for successful tumor control. Intraoperative laparoscopic ultrasonography is useful for tumor localization, but the ultrasound probe is controlled by the assistant rather than the surgeon. We evaluated our initial experience using a robotic ultrasound probe that is controlled by the console surgeon. METHODS: Partial nephrectomy was carried out in 22 consecutive patients between November 2010 and March 2011. A robotic ultrasound probe under console surgeon control was used in all the cases. All patients had at least 1 year follow up. RESULTS: Mean patient age was 59 years and mean tumor size was 2.7 cm. There were six hilar tumors (27%) and 21 (95%) endophytic tumors. Mean R.E.N.A.L. nephrometry score was 6.9 (range 6-9). Mean operative time was 205.7 min and mean warm ischemia time was 17.9 min (range 6-28 min). All patients had negative tumor margins and were free of disease recurrence at a mean follow up of 13 months. CONCLUSION: The use of a robotic ultrasound probe during partial nephrectomy allows the surgeon to optimize tumor identification with maximal autonomy, and to benefit from the precision and articulation of the robotic instrument during this key step of the partial nephrectomy procedure.

The C. elegans rab family: identification, classification and toolkit construction.

Rab monomeric GTPases regulate specific aspects of vesicle transport in eukaryotes including coat recruitment, uncoating, fission, motility, target selection and fusion. Moreover, individual Rab proteins function at specific sites within the cell, for example the ER, golgi and early endosome. Importantly, the localization and function of individual Rab subfamily members are often conserved underscoring the significant contributions that model organisms such as Caenorhabditis elegans can make towards a better understanding of human disease caused by Rab and vesicle trafficking malfunction. With this in mind, a bioinformatics approach was first taken to identify and classify the complete C. elegans Rab family placing individual Rabs into specific subfamilies based on molecular phylogenetics. For genes that were difficult to classify by sequence similarity alone, we did a comparative analysis of intron position among specific subfamilies from yeast to humans. This two-pronged approach allowed the classification of 30 out of 31 C. elegans Rab proteins identified here including Rab31/Rab50, a likely member of the last eukaryotic common ancestor (LECA). Second, a molecular toolset was created to facilitate research on biological processes that involve Rab proteins. Specifically, we used Gateway-compatible C. elegans ORFeome clones as starting material to create 44 full-length, sequence-verified, dominant-negative (DN) and constitutive active (CA) rab open reading frames (ORFs). Development of this toolset provided independent research projects for students enrolled in a research-based molecular techniques course at California State University, East Bay (CSUEB).

Risk factors for heparin-induced thrombocytopenia type II in aneurysmal subarachnoid hemorrhage.

BACKGROUND: Heparin-induced thrombocytopenia type II (HIT II) correlates with a higher incidence of thromboembolic complications and unfavorable outcome. OBJECTIVE: To examine the risk factors and outcomes for patients with HIT II with aneurysmal subarachnoid hemorrhage. METHODS: Demographics, risk factors, treatments, and outcomes data of 600 aneurysmal subarachnoid hemorrhage patients admitted to the University of Illinois Medical Center in Chicago between June 2002 and July 2007 were retrospectively reviewed. Patients meeting the clinical criteria for HIT II were compared with those who did not develop thrombocytopenia. RESULTS: Twenty-five patients (6%) met the clinical criteria for HIT II, and 396 (94%) did not develop thrombocytopenia. Both groups were the same with respect to age, Hunt-Hess score and Fisher grade on admission, medical conditions, and social risk factors. The HIT II patients had significantly more unfavorable outcomes (modified Rankin Scale score >3), deep vein thrombosis, stroke, pulmonary embolism, and death. Development of HIT II was strongly associated with symptomatic vasospasm (odds ratio, 5.7; 95% confidence interval, 2.5-13.1; P < .001) and number of angiographic procedures (odds ratio, 1.7; 95% confidence interval, 1.3-2.2; P < .001). Forward buildup selection modeling demonstrated the latter to be the strongest predictor for HIT II development (odds ratio, 2.3; 95% confidence interval, 1.7-3.2; P = .02). CONCLUSION: Heparin-induced thrombocytopenia type II correlates with a worse outcome and higher risk of thromboembolic complications in aneurysmal subarachnoid hemorrhage patients. In addition, HIT II was strongly associated with the number of angiographic procedures performed during the same hospitalization.

Robotic partial nephrectomy using robotic bulldog clamps.

BACKGROUND AND OBJECTIVES: The need for a skilled assistant to perform hilar clamping during robotic partial nephrectomy is a potential limitation of the technique. We describe our experience using robotic bulldog clamps applied by the console surgeon for hilar clamping. METHODS: A total of 60 consecutive patients underwent robotic partial nephrectomy, 30 using laparoscopic bulldog clamps applied by the assistant and 30 using robotic bulldog clamps applied with the robotic Prograsp instrument. Perioperative outcomes were compared between groups. RESULTS: All 30 patients underwent successful hilar clamping during robotic partial nephrectomy using robotic bulldog clamps with no intraoperative complications and without the need for readjustment/reclamping. Robotic bulldog clamps provided adequate ischemia even for tumors >4 cm, hilar, endophytic, multiple tumors, and multiple renal arteries. Both groups had similar baseline characteristics. Perioperative outcomes with robotic bulldog clamps were at least comparable to the laparoscopic bulldog group, with a trend to lower console time, warm ischemia time, and estimated blood loss. CONCLUSIONS: Use of robotically applied bulldog clamps is a safe and feasible method of hilar occlusion during robotic partial nephrectomy; they perform at least as well as laparoscopic bulldog clamps while allowing the console surgeon greater autonomy and precision for hilar clamping.

Effect of acute cocaine use on vasospasm and outcome in aneurysmal subarachnoid hemorrhage.

BACKGROUND: Although acute cocaine use has been correlated with aneurysmal subarachnoid hemorrhage, its effect on vasospasm and outcome is controversial. We investigated the effect of acute cocaine use on response to vasospasm treatment and neurologic outcome in patients with aneurysmal subarachnoid hemorrhage. METHODS: Data from 600 patients with aneurysmal subarachnoid hemorrhage admitted to the University of Illinois Medical Center in Chicago between June 2002 and July 2007 were retrospectively analyzed. Patients who were positive for cocaine on urine toxicology or admitted to cocaine use within 72 hours of admission were compared with control patients with no history of cocaine use. Patients with unknown or remote history were excluded. RESULTS: Of the 600 patients with aneurysmal subarachnoid hemorrhage, 27 (5%) were excluded. Thirty-one patients (5%) acutely used cocaine before admission. Cocaine users were younger than control (45.1 vs 54.1; P ≤ .0003), and were more likely to smoke tobacco, drink alcohol, and have renal dysfunction. There was no significant difference in Hunt-Hess or Fisher grade. In univariate and multivariate analyses, there was no difference in unfavorable short-term outcome (modified Rankin scale > 3), incidence of symptomatic or radiologic vasospasm, stroke, or death. The number of interventional procedures for the treatment of vasospasm did not differ between the two groups. CONCLUSIONS: There is no significant difference in incidence of symptomatic vasospasm or neurologic outcome between cocaine users and nonusers. The severity of the vasospasm and the response to treatment, as indicated by the number of vasospasm interventions, did not differ between the two groups.

Outcome following symptomatic cerebral vasospasm on presentation in aneurysmal subarachnoid hemorrhage: coiling vs. clipping.

BACKGROUND: Cerebral vasospasm complicates both surgical and endovascular treatment of ruptured aneurysms. The present study analyzes patients with presentation vasospasm (PVSP) treated in the acute setting and compares outcomes in those treated with surgical clipping versus endovascular coiling. METHODS: Data from 600 aneurysmal subarachnoid hemorrhage (aSAH) patients who were admitted to the University of Illinois Medical Center in Chicago between June 2002 and July 2007 were retrospectively reviewed. Patients with clinical vasospasm on presentation were compared with patients who developed delayed vasospasm during hospitalization. Subgroup analysis compared outcomes in patients with vasospasm on presentation treated with surgical clipping versus endovascular coiling. RESULTS: Of the 600 aSAH patients, 30 (5%) patients presented with symptomatic vasospasm (PVSP) confirmed by cerebral angiography and 179 (30%) patients were diagnosed with symptomatic vasospasm following admission (delayed vasospasm after admission [DVSP]). Patients admitted with vasospasm showed longer latency to admission after the rupture (5.5 vs. 1.5 day, P ≤ 0.001) but comparable latency to onset of symptomatic vasospasm after rupture. There was no significant difference between the two groups with respect to unfavorable outcome (modified Rankin Scale score > 3), death, or stroke. Therefore, aneurysm treatment during the vasospasm period did not result in increased morbidity in those patients. Within the subgroup of patients presenting with vasospasm on admission, there was no significant difference in outcome between patients who were treated with clipping versus coiling. CONCLUSIONS: Outcome did not differ between aSAH patients treated in the presence of symptomatic vasospasm compared to those with subsequent vasospasm. The outcome of patients presenting with vasospasm was not influenced by the modality of aneurysm treatment. This suggests that both surgical and endovascular intervention for the treatment of ruptured aneurysms are equally valid options in the setting of existing symptomatic vasospasm.

Brainstem auditory evoked potentials--a review and modified studies in healthy subjects.

The authors review the brainstem auditory evoked potential (BAEP), and present studies on 40 healthy subjects. In addition to the conventional click evoked BAEP, three modified BAEP examinations were performed. The modified BAEP tests include a 1,000 Hz tone-burst BAEP, and more rapid rate binaural click and 1,000 Hz tone-burst BAEPs-each of the last two studies performed at four diminishing moderate intensities. In addition to the usual parameters, the authors examined the Wave V to Vn interpeak latency, and stimulus intensity versus Wave V latency and amplitude functions in the rapid rate binaural studies. Studies were also repeated on healthy subjects in a dependant head position in an attempt to increase intracranial pressure. Discussion centers on the BAEP, its current utility in medicine, unique neurophysiology, and literature support that the above modifications could increase the practicality of the test in patients at risk with intracranial lesions and perhaps improve the feasibility for real-time continuous or frequent monitoring in the future.