BACKGROUND: Detection of pancreatic cancer (PaC), particularly at early stages, remains a great challenge owing to lack of specific biomarkers. We sought to identify a PaC-specific serum microRNA (miRNA) expression profile and test its specificity and sensitivity as a biomarker in the diagnosis and prognosis of PaC. METHODS: We obtained serum samples from 197 PaC cases and 158 age- and sex-matched cancer-free controls. We screened the differentially expressed serum miRNAs with Illumina sequencing by synthesis technology using pooled serum samples followed by RT-qPCR validation of a large number of samples arranged in multiple stages. We used risk score analysis to evaluate the diagnostic value of the serum miRNA profiling system. To assess the serum miRNA–based biomarker accuracy in predicting PaC, we performed additional double-blind testing in 77 PaC cases and 52 controls and diagnostic classification in 55 cases with clinically suspected PaC. RESULTS: After the selection and validation process, 7 miRNAs displayed significantly different expression levels in PaC compared with controls. This 7 miRNA–based biomarker had high sensitivity and specificity for distinguishing various stages of PaC from cancer-free controls and also accurately discriminated PaC patients from chronic pancreatitis (CP) patients. Among the 7 miRNAs, miR-21 levels in serum were significantly associated with overall PaC survival. The diagnostic accuracy rate of the 7-miRNA profile was 83.6% in correctly classifying 55 cases with clinically suspected PaC. CONCLUSIONS: These data demonstrate that the 7 miRNA–based biomarker can serve as a novel noninvasive approach for PaC diagnosis and prognosis.

BACKGROUND: Sensitive and specific biomarkers for the early detection of esophageal squamous cell carcinoma (ESCC) are urgently needed to reduce the high morbidity and mortality of the disease. The discovery of serum microRNAs (miRNAs) and their unique concentration profiles in patients with various diseases makes them attractive, novel noninvasive biomarkers for tumor diagnosis. In this study, we investigated the serum miRNA profile in ESCC patients to develop a novel diagnostic ESCC biomarker. METHODS: Serum samples were taken from 290 ESCC patients and 140 age- and sex-matched controls. Solexa sequencing technology was used for an initial screen of miRNAs in serum samples from 141 patients and 40 controls. A hydrolysis probe–based stem–loop quantitative reverse-transcription PCR (RT-qPCR) assay was conducted in the training and verification phases to confirm the concentrations of selected miRNAs in serum samples from 149 patients and 100 controls. RESULTS: The Solexa sequencing results demonstrated marked upregulation of 25 serum miRNAs in ESCC patients compared with controls. RT-qPCR analysis identified a profile of 7 serum miRNAs (miR-10a, miR-22, miR-100, miR-148b, miR-223, miR-133a, and miR-127-3p) as ESCC biomarkers. The area under the ROC curve for the selected miRNAs ranged from 0.817 to 0.949, significantly higher than for carcinoembryonic antigen (0.549; P < 0.0005). More importantly, this panel of 7 miRNAs clearly distinguished stage I/II ESCC patients from controls. CONCLUSIONS: This panel of 7 serum miRNAs holds promise as a novel blood-based biomarker for the diagnosis of ESCC.

The detection of nonsmall cell lung cancer (NSCLC) at an early stage presents a daunting challenge due to the lack of a specific noninvasive marker. The discovery of microRNAs (miRNAs), particularly those found in serum, has opened a new avenue for tumor diagnosis. To determine whether the expression profile of serum miRNAs can serve as a NSCLC fingerprint, we performed Taqman probe‐based quantitative RT‐PCR assay to selected differentially expressed serum miRNAs from a sample set including 400 NSCLC cases and 220 controls, and risk score analysis to evaluate the diagnostic value of the serum miRNA profiling system. After a two‐phase selection and validation process, 10 miRNAs were found to have significantly different expression levels in NSCLC serum samples compared with the control serum samples. Risk score analysis showed that this panel of miRNAs was able to distinguish NSCLC cases from controls with high sensitivity and specificity. Under ROC curves, the AUC for tumor identification in training set and validation set were 0.966 and 0.972, respectively. Furthermore, the expression profile of the 10‐serum miRNAs was correlated with the stage of NSCLC patients, especially in younger patients and patients with current smoking habits. More importantly, the serum miRNA‐based biomarker for early NSCLC detection was supported by a retrospective analysis in which the 10‐serum miRNA profile could accurately classify serum samples collected up to 33 months ahead of the clinical NSCLC diagnosis. Taken together, we demonstrate that the profiling of 10‐serum miRNAs provides a novel noninvasive biomarker for NSCLC diagnosis.

BACKGROUND: Although microRNAs (miRNAs) play essential roles in spermatogenesis, little is known about seminal plasma miRNAs in infertile men. We investigated the profile of seminal plasma miRNAs in infertile men to identify miRNAs that are altered in infertility; we then evaluated their diagnostic value.METHODS: Seminal plasma samples were obtained from 289 infertile men and 168 age-matched fertile control individuals. The stability of the miRNAs was first assessed by time-course and freeze–thaw cycle analyses. The Solexa sequencing technology was used for an initial screen of the miRNAs in samples pooled from 45 patients with nonobstructive azoospermia, 58 patients with asthenozoospermia, and 100 fertile controls. A stem–loop quantitative reverse-transcription PCR (RT-qPCR) assay was conducted in the training and verification sets to confirm the concentrations of the altered miRNAs in 73 patients with nonobstructive azoospermia, 79 patients with asthenozoospermia, 34 patients with oligospermia, and 68 fertile controls.RESULTS: The miRNAs in seminal plasma were stable. The Solexa sequencing analysis demonstrated 19 markedly altered miRNAs in the patient groups, compared with the control group. RT-qPCR analysis identified 7 miRNAs (miR-34c-5p, miR-122, miR-146b-5p, miR-181a, miR-374b, miR-509–5p, and miR-513a-5p) as markedly decreased in azoospermia but increased in asthenozoospermia. The area under the ROC curve for these miRNAs ranged from 0.733 to 0.921, markedly higher than for routine biochemical parameters (0.510–0.622). Moreover, the concentrations of some selected miRNAs were also increased in the semen sperm of the asthenozoospermia patients.CONCLUSIONS: The measurement of miRNAs in seminal plasma provides a novel, noninvasive approach for diagnosing male infertility.