Urinary LRRK2 phosphorylation predicts parkinsonian phenotypes in G2019S LRRK2 carriers.

OBJECTIVE: To test whether phosphorylated Ser-1292 LRRK2 levels in urine exosomes predicts LRRK2 mutation carriers (LRRK2+) and noncarriers (LRRK2-) with Parkinson disease (PD+) and without Parkinson disease (PD-). METHODS: LRRK2 protein was purified from urinary exosomes collected from participants in 2 independent cohorts. The first cohort included 14 men (LRRK2+/PD+, n = 7; LRRK2-/PD+, n = 4; LRRK2-/PD-, n = 3). The second cohort included 62 men (LRRK2-/PD-, n = 16; LRRK2+/PD-, n = 16; LRRK2+/PD+, n = 14; LRRK2-/PD+, n = 16). The ratio of Ser(P)-1292 LRRK2 to total LRRK2 was compared between LRRK2+/PD+ and LRRK2- in the first cohort and between LRRK2 G2019S carriers with and without PD in the second cohort. RESULTS: LRRK2+/PD+ had higher ratios of Ser(P)-1292 LRRK2 to total LRRK2 than LRRK2-/PD- (4.8-fold, p < 0.001) and LRRK2-/PD+ (4.6-fold, p < 0.001). Among mutation carriers, those with PD had higher Ser(P)-1292 LRRK2 to total LRRK2 than those without PD (2.2-fold, p < 0.001). Ser(P)-1292 LRRK2 levels predicted symptomatic from asymptomatic carriers with an area under the receiver operating characteristic curve of 0.844. CONCLUSION: Elevated ratio of phosphorylated Ser-1292 LRRK2 to total LRRK2 in urine exosomes predicted LRRK2 mutation status and PD risk among LRRK2 mutation carriers. Future studies may explore whether interventions that reduce this ratio may also reduce PD risk.

Proteomic Analysis of Urine to Identify Breast Cancer Biomarker Candidates Using a Label-Free LC-MS/MS Approach.

INTRODUCTION: Breast cancer is a complex heterogeneous disease and is a leading cause of death in women. Early diagnosis and monitoring progression of breast cancer are important for improving prognosis. The aim of this study was to identify protein biomarkers in urine for early screening detection and monitoring invasive breast cancer progression. METHOD: We performed a comparative proteomic analysis using ion count relative quantification label free LC-MS/MS analysis of urine from breast cancer patients (n = 20) and healthy control women (n = 20). RESULTS: Unbiased label free LC-MS/MS-based proteomics was used to provide a profile of abundant proteins in the biological system of breast cancer patients. Data analysis revealed 59 urinary proteins that were significantly different in breast cancer patients compared to the normal control subjects (p<0.05, fold change >3). Thirty-six urinary proteins were exclusively found in specific breast cancer stages, with 24 increasing and 12 decreasing in their abundance. Amongst the 59 significant urinary proteins identified, a list of 13 novel up-regulated proteins were revealed that may be used to detect breast cancer. These include stage specific markers associated with pre-invasive breast cancer in the ductal carcinoma in-situ (DCIS) samples (Leucine LRC36, MAST4 and Uncharacterized protein CI131), early invasive breast cancer (DYH8, HBA, PEPA, uncharacterized protein C4orf14 (CD014), filaggrin and MMRN2) and metastatic breast cancer (AGRIN, NEGR1, FIBA and Keratin KIC10). Preliminary validation of 3 potential markers (ECM1, MAST4 and filaggrin) identified was performed in breast cancer cell lines by Western blotting. One potential marker MAST4 was further validated in human breast cancer tissues as well as individual human breast cancer urine samples with immunohistochemistry and Western blotting, respectively. CONCLUSIONS: Our results indicate that urine is a useful non-invasive source of biomarkers and the profile patterns (biomarkers) identified, have potential for clinical use in the detection of BC. Validation with a larger independent cohort of patients is required in the following study.

Increased DJ-1 in urine exosome of Korean males with Parkinson's disease.

Parkinson's disease (PD) is a difficult disease to diagnose although it is the second most common neurodegenerative disease. Recent studies show that exosome isolated from urine contains LRRK2 or DJ-1, proteins whose mutations cause PD. To investigate a potential use for urine exosomes as a tool for PD diagnosis, we compared levels of LRRK2, α-synuclein, and DJ-1 in urine exosomes isolated from Korean PD patients and non-PD controls. LRRK2 and DJ-1, but not α-synuclein, were detected in the urine exosome samples, as reported previously. We initially could not detect any significant difference in these protein levels between the patient and the control groups. However, when age, disease duration, L-dopa daily dose, and gender were considered as analytical parameters, LRRK2 and DJ-1 protein levels showed clear gender-dependent differences. In addition, DJ-1 level was significantly higher (1.7-fold) in male patients with PD than that in male non-PD controls and increased in an age-dependent manner in male patients with PD. Our observation might provide a clue to lead to a novel biomarker for PD diagnosis, at least in males.

Urinary serum- and glucocorticoid-inducible kinase SGK1 reflects renal injury in patients with immunoglobulin A nephropathy.

AIM: Serum- and glucocorticoid-inducible kinase SGK1 functions as an important regulator of transepithelial sodium transport by activating epithelial sodium channel in renal tubules. Considerable evidence demonstrated that SGK1 was associated with hypertension and fibrosing diseases, such as diabetic nephropathy and glomerulonephritis. The present study was performed to evaluate the role of SGK1 played in immunoglobulin A (IgA) nephropathy. METHODS: Seventy-six patients of biopsy-proven IgA nephropathy and 33 healthy volunteers were enrolled in this study. All patients and healthy volunteers' urinary and serum samples were tested for SGK1 expression by indirect enzyme-linked immunosorbent assay. Meanwhile all patients' renal tissues were semi-quantified for SGK1 expression by immunohistochemistry assay. The relationships between SGK1 expressions and clinical or pathological parameters were also assessed. RESULTS: SGK1 expression was upregulated in urine and renal tubules in patients of Oxford classification T1 and T2, whereas its expression in serum did not increase significantly. Relationship analysis indicated that urinary and tissue SGK1 expressions were associated with heavy proteinuria and renal insufficiency in patients with IgA nephropathy. On the other hand, RAS blockades would reduce the SGK1 levels both in urine and renal tissues. CONCLUSION: These results suggested that urinary SGK1 should be a good indicator of tubulointerstitial damage in patients of IgA nephropathy. SGK1 expressions in urine and renal tissues were associated with the activity of renin-angiotensin-aldosterone system.

Stage-specific quantitative changes in renal and urinary proteome during the progression and development of streptozotocin-induced diabetic nephropathy in rats.

Diabetic nephropathy (DN) is a microvascular complication associated with diabetes causing slow deterioration of kidneys leading to end-stage renal disease. Timely intervention and diagnosis are crucial in order to ameliorate and halt the progression of DN. Current diagnosis of DN consists of urine assays for detection of microalbuminuria, which have inadequate specificity and sensitivity. Hence, there arises a need to discover stage-specific biomarkers which can aid in the early detection of DN and also in identifying the mechanisms underlying pathogenesis of DN. Therefore the present study was undertaken to identify the differentially expressed proteins in the urine and to examine the pattern of proteomic changes occurring in the rat kidneys during the course of progression of streptozotocin-induced model of DN in rats. Two-dimensional gel electrophoresis coupled to MALDI-TOF mass spectrometry was employed to identify the differentially expressed proteins under diabetic conditions. Among the identified proteins Calgranulin A and Calgranulin B appeared in the urinary proteome at the fourth week of induction of diabetes while we recorded a time-dependent decrease in the expression of major urinary protein (alpha 2u globulin) in the urine as well as kidneys of diabetic rats. Parallel monitoring of targeted proteomic changes in the renal proteome revealed an increase in histone H2B phosphorylation at serine14 along with a gradual decrease in Bcl-2 and MMP-13 expression during the course of progression and development of streptozotocin-induced DN.

TGF-B1 pathway as biological marker of bladder carcinoma schistosomal and non-schistosomal.

OBJECTIVES: Study TGF-ß1 pathway in bladder carcinoma. DESIGN AND METHODS: Eighty-one patients were enrolled: 16 chronic cystitis and 60 malignant bladder lesions; 15 schistosomal squamous cell carcinoma (SQCC), 45 transitional cell carcinoma (TCC). Five healthy individuals served as controls. mTGF-ß1, protein, and its receptor expression in urine and bladder tissue were measured using in situ hybridization and immunohistochemical techniques, respectively. RESULTS: Overexpression of TGF-mRNA in invasive TCC group was compared with superficial TCC, high grade TCC was compared with low grade, and SQCC was compared with TCC. TGF-ß1 protein and its receptor I (TGF-ßR1) were overexpressed in urine samples in malignant group compared with chronic cystitis and in SQCC group compared with TCC group. TGF-ß1 protein and its receptor were significantly increased in schistosomal malignant group compared with non-schistosomal group. CONCLUSION: Expression of TGF-ß1 and TGF-ßR1 could be used as biological markers of bladder carcinoma.

Identification of urine PLK2 as a marker of bladder tumors by proteomic analysis.

OBJECTIVE: To determine the patterns of urinary proteins in bladder cancer subjects using pooled urine from 27 bladder cancer patients. METHODS: The urine matrix was removed by acetonitrile precipitation followed by molecular weight cutoff. High performance liquid chromatography coupled with electrospray ionization tandem mass spectrometry (HPLC-ESI-MS/MS) was used to analyze the urinary proteome. The candidate protein was validated by western blot. RESULTS: A total of 146 urinary proteins were identified. The protein list was screened using bioinformatic tools, and 11 cancer-related urinary proteins were found to be potential tumor markers for bladder cancer. However, only PLK2 was identified with high confidence. This candidate protein was validated by western blot using urine samples from 14 normal subjects and 10 bladder cancer patients. Statistically significant correlations were detected between PLK2 expression and bladder transitional cell carcinoma (TCC) (P < 0.05). Urinary PLK2 had a sensitivity of 80% at a specificity of 64% for bladder TCC in the samples tested. CONCLUSIONS: Our results demonstrate overexpression of PLK2 in bladder carcinomas, suggesting a possible role of PLK2 in the pathogenesis of bladder carcinomas. However, the small cohort, preliminary results, and lack of subgroup analysis (such as carcinoma in situ, high grade, and stage) in this study prevent us from drawing definitive conclusions about the diagnostic value of PLK2 in these patients. Further studies directed toward a multitude of possible carcinogenic mechanisms of PLK2 in bladder cancer are warranted.

Quantitation of Aurora kinase A gene copy number in urine sediments and bladder cancer detection.

BACKGROUND: Chromosome missegregation and the resulting aneuploidy is a common change in neoplasia. The Aurora kinase A (AURKA) gene, which encodes a key regulator of mitosis, is frequently amplified and/or overexpressed in cancer cells, and the level of AURKA amplification is associated with the level of aneuploidy. We examined whether AURKA gene amplification is a biomarker for the detection of bladder cancer. METHODS: The effect of ectopic expression of Aurora kinase A (AURKA) using an adenoviral vector in simian virus 40-immortalized urothelial cells (SV-HUC) on centrosome multiplication and chromosome copy number was measured in vitro by immunofluorescence and fluorescence in situ hybridization (FISH), respectively. The FISH test was also used to examine AURKA gene copy number in exfoliated cells in voided urine samples from 23 patients with bladder cancer and 7 healthy control subjects (training set), generating a model for bladder cancer detection that was subsequently validated in an independent set of voided urine samples from 100 bladder cancer patients and 148 control subjects (92 healthy individuals and 56 patients with benign urologic disorders). An AURKA gene score (the proportion of cells with three or more AURKA signals) was used to produce receiver operating characteristic (ROC) curves and to calculate the specificity and sensitivity of the AURKA FISH test. Differences between mean AURKA scores in different pathogenetic groups of bladder cancer stratified according to histological grade and stage were tested by unpaired Mann-Whitney t tests or one-way Wilcoxon tests. All statistical tests were two-sided. RESULTS: Forced overexpression of AURKA in urothelial cells induced amplification of centrosomes, chromosome missegregation, and aneuploidy, and natural overexpression was detectable in in situ lesions from patients with bladder cancer. The FISH test for the AURKA gene copy number performed on the validation set yielded a specificity of 96.6% (95% confidence interval [CI] = 92.3% to 98.5%) and sensitivity of 87% (95% CI = 79.0% to 92.2%) and an area under the ROC curve of 0.939 (95% CI = 0.906 to 0.971; P < .001). CONCLUSION: Overexpression of AURKA can cause aneuploidy in urothelial cells, and the AURKA gene copy number is a promising biomarker for detection of bladder cancer.