PD-L1 pathway as a novel target in carcinosarcoma of the kidney and renal pelvis.

Carcinosarcoma of the kidney and renal pelvis (CSKP) is a rare and highly-aggressive malignancy characterized by rapid progression and widespread metastases. To date, few studies describe the natural history of the disease. We present a patient placed on pembrolizumab therapy for suspected metastatic colon cancer. The patient was found to have a right renal mass with caval extension on surveillance and ultimately underwent radical surgery revealing carcinosarcoma with positive PD-L1 expression with no evidence of recurrence to date. To our knowledge, this is the first case describing PD-L1 expression in CSKP and presents a novel pathway for future treatment algorithms.

Initial Experience with the Use of a Robotic Stapler for Robot-Assisted Donor Nephrectomy.

INTRODUCTION: Since the first description of robot-assisted laparoscopic donor nephrectomy for living donor renal transplantation, additional studies have noted outcomes comparable to traditional laparoscopic surgery. Urologists have embraced the technical advantages of the robotic approach, including improved dissection and more accurate graft preservation. With the advent of robotic stapling, we aim to demonstrate the feasibility of the use of robotic stapling for living-donor nephrectomies. MATERIALS AND METHODS: Ten cases of da Vinci® EndoWrist® Stapler use during robot-assisted donor nephrectomy by a single surgeon are reported. Variables examined included patient anatomy, estimated blood loss (EBL), warm ischemia time (WIT), postoperative complications, and graft function at follow-up. The costs of the laparoscopic and robotic staplers at our institution are reported. RESULTS: One right and nine left nephrectomies were performed by a single surgeon. Eight living donors had a single renal artery and vein, while two had multiple renal arteries and renal veins. A single vascular stapler load (45-mm, white cartridge) was used for vessels in all cases. WIT was <6 minutes in each case, and EBL ranged from 13 to 100 mL. Sufficient length on the renal artery and vein was obtained to execute anastomoses in all cases. Only one patient had postoperative complications that were related to anesthesia. Graft function of recipients and postoperative renal function has been adequate to date. The cost of using the robotic stapler was $705 (EndoWrist Stapler), and the cost of the laparoscopic stapler (Endo GIA™ Stapler; Medtronic, Dublin, Ireland) was $494.06. CONCLUSIONS: The use of robotic stapler is feasible in terms of patient safety, technique, postoperative outcomes, and cost in both left- and right-sided living-donor robotic nephrectomies. Further research is needed to confirm the benefit and safety of EndoWrist stapler use in robotic donor nephrectomies compared to laparoscopic stapler use.

Dietary n-3:n-6 fatty acid ratios differentially influence hormonal signature in a rodent model of metabolic syndrome relative to healthy controls.

Dietary ratios of omega-3 (n-3) to omega-6 (n-6) polyunsaturated fatty acids (PUFAs) have been implicated in controlling markers of the metabolic syndrome, including insulin sensitivity, inflammation, lipid profiles and adiposity. However, the role of dietary PUFAs in regulating energy systems in healthy relative to metabolic diseased backgrounds has not been systematically addressed. We used dietary manipulation of n-3 to n-6 PUFA ratios in an animal model of metabolic syndrome and a related healthy line to assay feeding behavior and endocrine markers of feeding drive and energy regulation. Two related lines of rodents with a healthy and a metabolic syndrome phenotype were fed one of two isocaloric diets, comprised of either a 1:1 or a 1:30 n-3 to n-6 ratio, for 30 days. Food intake and weight gain were monitored; and leptin, ghrelin, adiponectin and a suite of hypothalamic neuropeptides involved in energy regulation were assayed following the dietary manipulation period. There was no difference in caloric intake or weight gain between diet groups, however there was a significant interaction between diet and phenotypic line on central and peripheral markers of energy homeostasis. Thus serum levels of leptin, acylated-ghrelin and adiponectin, and mRNA levels of the anorexigenic hypothalamic neuropeptide, cocaine-amphetamine related transcript (CART), showed differential, dietary responses with HCR rats showing an increase in anorexigenic signals in response to unbalanced n-3:6 ratios, while LCR did not. These data are the first to demonstrate that a rodent line with a metabolic syndrome-like phenotype responds differentially to dietary manipulation of n-3 and n-6 fatty acids relative to a related healthy line with regard to endocrine markers of energy homeostasis. The dietary n-3:n-6 ratios used in this experiment represent extreme points of natural human diets, however the data suggest that optimal recommendations regarding omega-3 and omega-6 intake may have differing effects in healthy subjects relative to metabolic syndrome patients. Further research is necessary to establish these responses in human populations.

Upregulation of GAD65 mRNA in the medulla of the rat model of metabolic syndrome.

Metabolic syndrome is characterized by obesity, elevated blood pressure (BP), insulin resistance, and hypercholesterolemia. Recently an animal model of this disorder has been proposed in rats selectively bred based on their performance on a treadmill-running task. Accordingly, low capacity runner (LCR) rats exhibited all of the diagnostic criteria for metabolic syndrome, including elevated BP, as compared to their high capacity runner (HCR) counterparts [U. Wisløff, S.M. Najjar, O. Ellingsen, P.M. Haram, S. Swoap, Q. Al-Share, M. Fernstrom, K. Rezaei, S.J. Lee, L.G. Koch, S.L. Britton, Cardiovascular risk factors emerge after artificial selection for low aerobic capacity, Science 307 (2005) 418-420]. Previous studies have highlighted the importance of GABAergic neurotransmission in the medullary cardiovascular-regulatory areas in the central control of BP. Thus, we hypothesized a dysregulation in GABAergic transmission in the medullary cardiovascular-regulatory nuclei of LCR rats. To begin testing this hypothesis we carried out experiments examining expression of the GABA synthetic enzymes, GAD65 and GAD67, mRNAs in the two rat strains via radioactive in situ hybridization. Our results showed GAD65 and GAD67 mRNAs were widely expressed throughout the brainstem; quantification revealed increased GAD65 mRNA expression in LCR animals in the caudal nucleus tractus solitarius (NTS) and rostral ventrolateral medulla (VLM) as compared to HCR rats. Conversely, no differences in the expression of GAD67 were detected in these regions. These data are consistent with the notion of altered GABAergic neurotransmission in the NTS and VLM in metabolic syndrome, and point to the importance of these regions in cardiovascular regulation.

Combining laser capture microdissection with quantitative real-time PCR: effects of tissue manipulation on RNA quality and gene expression.

Laser capture microdissection (LCM) is increasingly being used in quantitative gene expression studies of the nervous system. The current study aimed at determining the impact of various tissue manipulations on the integrity of extracted RNA in LCM studies. Our data indicate that various tissue preparation strategies prior to microdissection may decrease RNA quality by as much as 25%, thus affecting expression profiles of some genes. To circumvent this problem, we developed a strategy for reverse transcriptase real-time PCR that has considerable sensitivity and can be used to calculate relative changes in gene expression. This approach was validated in subregions of the rat cerebellum. Accordingly, expression of glial gene markers - myelin-associated glycoprotein and proteolipid protein 1 - was found 70-160-fold higher in the white matter layer of the cerebellar cortex as compared to the neuron-enriched granular layer. In contrast, expression of a specific neuronal maker, neuron-specific enolase, was found seven-fold higher in the granular layer, as compared to the white matter layer. Furthermore, this approach had high sensitivity and specificity as we were able to detect a 38% decrease in the expression of neuron-specific enolase without a change in the expression of glial markers following administration of the neurotoxin, ibotenic acid. These results demonstrate feasibility of performing accurate semi-quantitative gene expression analyses in LCM samples.