A Proposal for Revised and Simplified Renal Pelvic Urothelial Carcinoma Staging Criteria: A Clinicopathologic Study of 141 Tumors.

Staging of renal pelvic urothelial carcinoma can be challenging due to anatomic variation at the renal pelvis compared with ureter and bladder and calls into question the prognostic accuracy of the current TNM staging. In this study, we determined staging and cancer-specific survival (CSS) in 141 patients undergoing nephroureterectomy for renal pelvic urothelial carcinoma (pTa=50, pT1=29, pT2=10, pT3=36, and pT4=16). Under current staging criteria, we found no significant difference in CSS between adjacent staging categories step-wise across pTa, pT1, pT2, and pT3 tumors.

Pathology of hereditary renal cell carcinoma syndromes: Tuberous sclerosis complex (TSC).

Tuberous sclerosis complex (TSC) is an autosomal dominant genetic disease characterized by hamartomatous tumors involving multiple organs such as the brain, skin, heart, lung and kidney. TSC is caused by inactivating mutations in TSC1/TSC2, which encodes hamartin and tuberin, respectively, and forms a complex that regulates mechanistic target of rapamycin complex 1 (mTORC1), resulting in cell overgrowth and oncogenesis. Since a leading cause of morbidity and mortality in TSC relates to chronic kidney disease and the ability to preserve renal function, this review describes the important pathologic findings in TSC-associated renal neoplasms and their correlating sporadic counterparts.

Ornithine aminotransferase supports polyamine synthesis in pancreatic cancer.

There is a need to develop effective therapies for pancreatic ductal adenocarcinoma (PDA), a highly lethal malignancy with increasing incidence and poor prognosis. Although targeting tumour metabolism has been the focus of intense investigation for more than a decade, tumour metabolic plasticity and high risk of toxicity have limited this anticancer strategy. Here we use genetic and pharmacological approaches in human and mouse in vitro and in vivo models to show that PDA has a distinct dependence on de novo ornithine synthesis from glutamine.

A proteolytic method for evaluating O-GlcNAcylation on proteins of similar molecular weight to antibody heavy chain after immunoprecipitation.

Investigating a protein of interest that runs at the same molecular weight as antibody heavy chain is a frequent deterrent to its evaluation by immunoprecipitation. Methods of minimizing the detection of the immunoprecipitating antibody are available. However, these still present a barrier to evaluating if intracellular proteins are modified by the O-GlcNAc post-translation protein modification due to interfering glycosylation on antibodies.

Elevated -GlcNAcylation enhances pro-inflammatory Th17 function by altering the intracellular lipid microenvironment.

Chronic, low-grade inflammation increases the risk for atherosclerosis, cancer, and autoimmunity in diseases such as obesity and diabetes. Levels of CD4 T helper 17 (Th17) cells, which secrete interleukin 17A (IL-17A), are increased in obesity and contribute to the inflammatory milieu; however, the relationship between signaling events triggered by excess nutrient levels and IL-17A-mediated inflammation is unclear. Here, using cytokine, quantitative real-time PCR, immunoprecipitation, and ChIP assays, along with lipidomics and MS-based approaches, we show that increased levels of the nutrient-responsive, post-translational protein modification, -GlcNAc, are present in naive CD4 T cells from a diet-induced obesity murine model and that elevated -GlcNAc levels increase IL-17A production.

O-GlcNAc: a novel regulator of immunometabolism.

The rapidly expanding field of immunometabolism focuses on how metabolism controls the function of immune cells. CD4 T cells are essential for the adaptive immune response leading to the eradication of specific pathogens. However, when T cells are inappropriately over-active, they can drive autoimmunity, allergic disease, and chronic inflammation.

Sustained GlcNAcylation reprograms mitochondrial function to regulate energy metabolism.

Dysfunctional mitochondria and generation of reactive oxygen species (ROS) promote chronic diseases, which have spurred interest in the molecular mechanisms underlying these conditions. Previously, we have demonstrated that disruption of post-translational modification of proteins with β-linked -acetylglucosamine (-GlcNAcylation) via overexpression of the GlcNAc-regulating enzymes GlcNAc transferase (OGT) or GlcNAcase (OGA) impairs mitochondrial function. Here, we report that sustained alterations in GlcNAcylation either by pharmacological or genetic manipulation also alter metabolic function.

Reduced O-GlcNAcase expression promotes mitotic errors and spindle defects.

Alterations in O-GlcNAc cycling, the addition and removal of O-GlcNAc, lead to mitotic defects and increased aneuploidy. Herein, we generated stable O-GlcNAcase (OGA, the enzyme that removes O-GlcNAc) knockdown HeLa cell lines and characterized the effect of the reduction in OGA activity on cell cycle progression. After release from G1/S, the OGA knockdown cells progressed normally through S phase but demonstrated mitotic exit defects.

Nonradioactive glycosyltransferase and sulfotransferase assay to study glycosaminoglycan biosynthesis.

Glycosaminoglycans (GAGs) are linear polysaccharides with repeating disaccharide units. GAGs include heparin, heparan sulfate, chondroitin sulfate, dermatan sulfate, keratan sulfate, and hyaluronan. All GAGs, except for hyaluronan, are usually sulfated.

Golgi-resident PAP-specific 3'-phosphatase-coupled sulfotransferase assays.

Sulfotransferases are a large group of enzymes that transfer a sulfonate group from the donor substrate, 3'-phosphoadenosine-5'-phosphosulfate (PAPS)(1), to various acceptor substrates, generating 3'-phosphoadenosine-5'-phosphate (PAP) as a by-product. A universal phosphatase-coupled sulfotransferase assay is described here. In this method, Golgi-resident PAP-specific 3'-phosphatase (gPAPP) is used to couple to a sulfotransferase reaction by releasing the 3'-phosphate from PAP.

Universal phosphatase-coupled glycosyltransferase assay.

A nonradioactive glycosyltransferase assay is described here. This method takes advantage of specific phosphatases that can be added into glycosyltransferase reactions to quantitatively release inorganic phosphate from the leaving groups of glycosyltransferase reactions. The released phosphate group is then detected using colorimetric malachite-based reagents.

Prenyltransferase substrate binding pocket flexibility and its application in isoprenoid profiling.

This communication explores prenyltransferase substrate binding pocket flexibility to tag and enrich isoprenoids using affinity-based purification for metabolomic studies.