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Background: MicroRNA expression is altered in cancer cells, and microRNAs could serve as diagnostic/prognostic biomarker for cancer patients. Our study was designed to analyze circulating serum microRNAs in patients with renal cell carcinoma (RCC). Methodology/Principal Findings: We first explored microRNA expression profiles in tissue and serum using TaqMan Low Density Arrays in each six malignant and benign samples: Although 109 microRNAs were circulating at higher levels in cancer patients' serum, we identified only 36 microRNAs with up-regulation in RCC tissue and serum of RCC patients. Seven candidate microRNAs were selected for verification based on the finding of up-regulation in serum and tissue of RCC patients: miR-7-1*, miR-93, miR-106b*, miR-210, miR-320b, miR-1233 and miR-1290 levels in serum of healthy controls (n = 30) and RCC (n = 33) patients were determined using quantitative real-time PCR (TaqMan MicroRNA Assays). miR-1233 was increased in RCC patients, and thus validated in a multicentre cohort of 84 RCC patients and 93 healthy controls using quantitative real-time PCR (sensitivity 77.4%, specificity 37.6%, AUC 0.588). We also studied 13 samples of patients with angiomyolipoma or oncocytoma, whose serum miR-1233 levels were similar to RCC patients. Circulating microRNAs were not correlated with clinical-pathological parameters. Conclusions/Significance: MicroRNA levels are distinctly increased in cancer patients, although only a small subset of circulating microRNAs has a tumor-specific origin. We identify circulating miR-1233 as a potential biomarker for RCC patients. Larger-scaled studies are warranted to fully explore the role of circulating microRNAs in RCC. [ABSTRACT FROM AUTHOR]

Purpose: DNA hypermethylation is a common cancer associated alteration. We analyzed methylation patterns of cell-free serum DNA in patients with testicular cancer. Materials and Methods: Hypermethylation at APC, GSTP1, PTGS2, p14(ARF), p16(INK) and RASSF1A was analyzed using real-time polymerase chain reaction following methylation sensitive restriction endonuclease treatment in 73 patients with testicular cancer and 35 healthy individuals. Results: Hypermethylation was more common in patients with testicular cancer than in healthy individuals, including APC 57% and 6%, p16(INK) 53% and 17%, p14(ARF) 53% and 0%, RASSF1A 47% and 0%, PTGS2 45% and 0%, and GSTP1 25% and 0%, respectively (each p <0.01). Methylation frequencies at the investigated gene sites were similar in nonseminoma and seminoma cases (p >0.05). Diagnostic information was increased when multiple gene sites were analyzed in combination (ROC AUC 0.834, 67% sensitivity and 97% specificity). Diagnostic information was superior to the analysis of AFP/HCG/PLAP/LDH (combined sensitivity 58% and AUC 0.791). The sensitivity of hypermethylation in patients with unsuspicious conventional tumor markers was 71% (AUC 0.871, 97% specificity). Hypermethylation at PTGS2 was more common in patients with pT1 stage tumors (p = 0.011). Conclusions: The detection of hypermethylated cell-free serum DNA has the potential of a useful additional diagnostic parameter in patients with testicular germ cell cancer. Furthermore, in cases without conventional tumor marker increases testing CpG island hypermethylation in cell-free circulation DNA may improve the ability to detect early and/or recurrent testicular cancer. [Copyright &y& Elsevier]

OBJECTIVE To analyse the diagnostic and prognostic value of cell-free mitochondrial (mt)DNA in patients with testicular cancer, as increased levels of cell-free circulating mtDNA have been reported in patients with cancer. PATIENTS, SUBJECTS AND METHODS In all, 74 patients with testicular cancer (seminoma in 39, nonseminoma in 35) and 35 healthy individuals were included in the study. Circulating DNA was isolated from 1 mL of serum. A quantitative real-time polymerase chain reaction was used to analyse the levels of a 79-bp (mtDNA-79) and 220 bp (mtDNA-220) fragment of the mitochondrial specific 16S-RNA. The mtDNA integrity was expressed as the ratio of mtDNA-220 to mtDNA-79. RESULTS mtDNA-79 and mtDNA-220 levels were significantly ( P < 0.001) greater in patients with testicular cancer than in healthy individuals. The mtDNA integrity was similar in patients and healthy controls ( P = 0.435). Receiver operator characteristic curve analysis showed that cell-free mtDNA (mtDNA-79) levels distinguished, with a sensitivity of 59.5% and a specificity of 94.3%, between patients and healthy individuals (area under curve, 0.787). Also, mtDNA-79 levels could be used to distinguish between patients (31) with conventional markers (α-fetoprotein, human chorionic gonadotrophin, placental alkaline phosphatase and lactate dehydrogenase) within normal ranges and healthy individuals, with a sensitivity of 64.5% and specificity of 91.4% (area under curve 0.797). Cell-free mtDNA levels were not correlated with any clinicopathological variable (pT stage, lymph node invasion, vascular invasion, clinical stage, International Germ Cell Cancer Collaborative Group classification, tumour markers; all P > 0.05). CONCLUSION Cell-free mtDNA levels are greater in patients with testicular cancer and might provide valuable information for managing patients with testicular anomalies, especially those with normal levels of established tumour markers. [ABSTRACT FROM AUTHOR]

OBJECTIVE To investigate the role of circulating mitochondrial DNA (mtDNA) in patients with localized prostate cancer, as recent reports show that patients with advanced cancer have increased levels of mtDNA. PATIENTS AND METHODS DNA was isolated from the serum of 100 patients with prostate cancer and 18 with benign prostate hyperplasia (BPH). A quantitative real-time polymerase chain reaction was used to amplify 79 bp and 230 bp fragments of the mitochondrial 16s-RNA gene, the short fragment representing total mtDNA, including mtDNA truncated by apoptosis, and the long fragment representing mostly mtDNA from other cell death entities. mtDNA integrity was defined as the ratio of long to short mtDNA fragments. RESULTS The short and long mtDNA levels, and mtDNA integrity, were similar in patients with BPH and cancer ( P = 0.940, 0.211 and 0.441, respectively), and were not correlated with clinical or pathological variables, e.g. age, prostate-specific antigen (PSA) level, cT stage, pT stage, seminal vesicle infiltration, lymph node invasion, or Gleason score ( P = 0.075 to 0.961). However, patients with high levels of short mtDNA (>75th percentile) had a greater risk of PSA progression and this variable was the strongest predictor of PSA recurrence in a multivariate Cox analysis ( P = 0.023; hazard ratio 0.31; 95% confidence interval 0.113–0.851). CONCLUSION Circulating mtDNA levels did not distinguish between patients with prostate cancer or BPH. However, there was a significant increase in short mtDNA fragments in patients with early PSA recurrence after radical prostatectomy. [ABSTRACT FROM AUTHOR]

Abstract: Objective: Cell-free circulating mitochondrial DNA (mtDNA) has been proposed as universal diagnostic and prognostic biomarker in cancer patients. Patients and methods: Cell-free DNA was isolated from 1 ml serum from patients with bladder cancer (BCA, n = 84), renal cell carcinoma (RCC, n = 33), and prostate cancer (CaP, n = 23), and compared with healthy individuals (n = 79). Quantitative real-time PCR was used to analyze the levels of a 79 bp (mtDNA-79), and 220 bp (mtDNA-220) fragment of the mitochondrial specific 16S-RNA. The mitochondrial DNA integrity (mtDNA-integrity) was defined as ratio of mtDNA-220 to mtDNA-79 fragments. Results: In healthy controls, mtDNA-79 levels were increased in male volunteers; mtDNA-230 levels and mtDNA-integrity were correlated with age. Neither mtDNA levels nor mtDNA-integrity were correlated with age or gender in cancer patients. Circulating mtDNA-79 (median 8.75 × 106 vs. 0.43 × 106 copies/ml) and mtDNA-230 (8.11 × 106 vs. 0.27 × 106 copies/ml) levels were significantly increased in cancer patients and allowed sensitive (84%) and specific (97%) discrimination from healthy controls. mtDNA levels were unequally distributed among the different cancer entities (mtDNA-79: BCA 9.54 × 106 vs. RCC 6.69 × 106 vs. CaP 4.48 × 106 copies/ml; mtDNA-230: BCA 9.78 × 106 vs. RCC 6.74 × 106 vs. CaP 1.94 × 106 copies/ml). The mtDNA-integrity was increased in RCC and BCA patients compared to control subjects and CaP patients. Serum mtDNA-integrity was correlated with pathological stage in RCC and with tumor grade in BCA patients. Conclusion: Circulating mtDNA levels are associated with gender and age in healthy individuals, but not in cancer patients. Quantification of circulating mtDNA may help identify patients with urologic malignancies. [Copyright &y& Elsevier]

Abstract: Patients with malignancies often possess increased concentrations of cell-free serum DNA. In this study, we investigated serum DNA levels in each 45 patients with bladder cancer (BCA) undergoing radical cystectomy and with benign prostate hyperplasia. A quantitative real-time PCR was used to amplify a 124bp (PTGS2; mostly apoptotic origin) and a 271bp (Reprimo; mostly necrotic origin) DNA fragment. Changes in the origin of DNA fragments were specified as the Apoptosis Index (AI, ratio of 124bp/271bp fragments). Small and large fragments were increased (p <0.001 and p =0.041) in BCA patients. The AI increase suggests that DNA fragmentation was mostly (p <0.001) caused by apoptosis. High levels of small DNA fragments distinguished between BCA and BPH with high sensitivity (96%) and moderate specificity (62%). DNA levels and the AI were not correlated with clinicopathological parameters. However, an increased AI was correlated with BCA-specific mortality in a multivariate analysis (p =0.011) indicating that the AI is an independent prognostic factor. Thus, cell-free DNA seems to be a useful prognostic marker in patients with BCA. [Copyright &y& Elsevier]

Objectives: To analyze circulating microRNAs (miRNA) in serum as non-invasive biomarker in patients with localized prostate cancer (PCA), benign prostate hyperplasia (BPH) and healthy individuals (HI). Methods: Total RNA was isolated from serum samples and the circulating levels of different RNA species (miRNA, miR-16; small nuclear RNA, RNU1A-1; messenger RNA, HPRT1), as well as of 4 oncogenic miRNAs (miR-26a, miR-32, miR-195, miR-let7i), were determined using a quantitative real-time polymerase chain reaction. We also evaluated miRNA levels in a second cohort of 10 PCA patients in cancer/nonmalignant tissue, and pre- and post-prostatectomy serum samples. Results: The levels of miR-16 and RNU1A-1were reliably measured, whereas HPRT1 levels were often below the detection limit of our assay. Circulating oncogenic miRNA levels were different, and especially the miR-26a level allowed sensitive (89%) discrimination of PCA and BPH patients at a moderate specificity (56%; area under the curve [AUC]: 0.703); the analysis of oncogenic miRNAs in combination increased the diagnostic accuracy (sensitivity: 78.4%; specificity: 66.7%; AUC: 0.758). Despite the low number of patients limiting the statistical power of the study, we observed correlations with clinical-pathologic parameters: miR-16, miR-195, and miR-26a were significantly correlated with surgical margin positivity; miR-195 and miR-let7i were significantly correlated with the Gleason score. Tissue miRNA levels were correlated with preprostatectomy miRNA levels in serum, and serum miRNA decreased after prostatectomy, thereby indicating tumor-associated release of miRNA. Conclusions: Tumor-associated miRNAs in serum allow noninvasive discrimination of PCA and BPH. [ABSTRACT FROM AUTHOR]