Serum Exosomal Dicer Is a Useful Biomarker for Early Detection of Differentiated Gastric Adenocarcinoma.

BACKGROUND AND AIM: A recent basic study identified that Dicer is contained in exosomes derived from cancer cells and plays crucial roles in microRNA maturation and cancer development. Based on this novel basic concept, we analyzed the usefulness of serum exosomal Dicer as a diagnostic biomarker for gastrointestinal cancers. METHODS: Enrolled participants (691) were categorized into 3 groups: gastric cancer (GC) cohort, 183 patients (90 healthy controls (HCs) and 93 GC patients); esophageal cancer (EC) cohort, 115 patients (90 HCs and 25 EC patients); and colorectal cancer (CRC) cohort, 188 patients (92 HCs and 96 CRC patients) after age- and sex matching using the propensity score. The quality of isolated serum exosomes was validated with an electron microscope, particle size analyzer, and exosome marker, CD63. RESULTS: Serum exosomal Dicer was significantly higher in the GC group than in the HC group (p = 0.004), whereas no significant differences were found in both EC and CRC cohorts. Serum exosomal Dicer was significantly higher in only differentiated gastric adenocarcinoma and not in the undifferentiated type. Moreover, serum exosomal Dicer showed no significant differences regardless of Helicobacter pylori (H. pylori) status. The biomarker panel combining serum exosomal Dicer with H. pylori status distinguished between HC and differentiated GC patients with an area under the curve (AUC) of 0.762. As for early-stage diagnosis, this combination distinguished between HC and stage I differentiated GC with an AUC = 0.758. CONCLUSIONS: Serum exosomal Dicer is a potential noninvasive diagnostic biomarker for early detection of differentiated gastric adenocarcinoma.

Towards precision medicine for stress disorders: diagnostic biomarkers and targeted drugs.

The biological fingerprint of environmental adversity may be key to understanding health and disease, as it encompasses the damage induced as well as the compensatory reactions of the organism. Metabolic and hormonal changes may be an informative but incomplete window into the underlying biology. We endeavored to identify objective blood gene expression biomarkers for psychological stress, a subjective sensation with biological roots. To quantify the stress perception at a particular moment in time, we used a simple visual analog scale for life stress in psychiatric patients, a high-risk group. Then, using a stepwise discovery, prioritization, validation, and testing in independent cohort design, we were successful in identifying gene expression biomarkers that were predictive of high-stress states and of future psychiatric hospitalizations related to stress, more so when personalized by gender and diagnosis. One of the top biomarkers that survived discovery, prioritization, validation, and testing was FKBP5, a well-known gene involved in stress response, which serves as a de facto reassuring positive control. We also compared our biomarker findings with telomere length (TL), another well-established biological marker of psychological stress and show that newly identified predictive biomarkers such as NUB1, APOL3, MAD1L1, or NKTR are comparable or better state or trait predictors of stress than TL or FKBP5. Over half of the top predictive biomarkers for stress also had prior evidence of involvement in suicide, and the majority of them had evidence in other psychiatric disorders, providing a molecular underpinning for the effects of stress in those disorders. Some of the biomarkers are targets of existing drugs, of potential utility in patient stratification, and pharmacogenomics approaches. Based on our studies and analyses, the biomarkers with the best overall convergent functional evidence (CFE) for involvement in stress were FKBP5, DDX6, B2M, LAIR1, RTN4, and NUB1. Moreover, the biomarker gene expression signatures yielded leads for possible new drug candidates and natural compounds upon bioinformatics drug repurposing analyses, such as calcium folinate and betulin. Our work may lead to improved diagnosis and treatment for stress disorders such as PTSD, that result in decreased quality of life and adverse outcomes, including addictions, violence, and suicide.

Low Drosha protein expression in cutaneous T-cell lymphoma is associated with worse disease outcome.

BACKGROUND: Dysregulation of microRNAs (miRNAs) key regulators may contribute to the pathogenesis of malignancies. miRNA machinery genes such Dicer and Drosha have been reported to be biomarkers in different cancer types. OBJECTIVES: We aimed to evaluate Drosha and Dicer protein expression in cutaneous T-cell lymphoma (CTCL). METHODS: We performed Drosha and Dicer immunohistochemistry in 45 patients with mycosis fungoides and subtypes. Drosha and Dicer expression scores were correlated with clinical parameters including disease-specific death (DSD), stage of disease and different laboratory data. Uni- and multivariate statistics were performed. RESULTS: On univariate analysis, elevated serum LDH and low Drosha expression were significantly associated with advanced stage (P = 0.032 and 0.0062, respectively) and lymphoma-specific death (LSD; P = 0.017 and P = 0.005, respectively). Moreover, elevated circulating CD4+/CD26- lymphocytes were significantly associated with advanced stage (P = 0.032) and DSD (P = 0.0098). On multivariate analysis, low Drosha expression remained in the logistic regression model as significant independent predictor for advanced disease stages [P = 0.013; odds ratio: 5 (confidence interval) CI 1.3-19.3]. Moreover, low Drosha expression (P = 0.026) and elevated LDH (P = 0.025) remained as significant independent predictors for DSD with odds ratios of 13.5 (CI 1.3-134.4 and 8.7 CI 1.3-57.2, respectively). CONCLUSIONS: Low Drosha expression is an independent predictor for advanced stage as well as LSD in CTCL patients indicating a tumour suppressor gene function of Drosha in this disorder.

Dicer Is Down-regulated and Correlated with Drosha in Idiopathic Sudden Sensorineural Hearing Loss.

Previously, we reported the expression levels of specific microRNA machinery components, DGCR8 and AGO2, and their clinical association in patients with idiopathic sudden hearing loss (SSNHL). In the present study, we investigated the other important components of microRNA machinery and their association with clinical parameters in SSNHL patients. Fifty-seven patients diagnosed with SSNHL and fifty healthy volunteers were included in this study. We evaluated mRNA expression levels of Dicer and Drosha in whole blood of patients with SSNHL and the control group, using RT & real-time PCR analysis. The Dicer mRNA expression level was down-regulated in patients with SSNHL. However, the Drosha mRNA expression level was not significantly altered in patients with SSNHL. Neither the Dicer nor Drosha mRNA expression level was not associated with any clinical parameters, including age, sex, duration of initial treatment from onset (days), initial Pure tone average, Siegel's criteria, WBC, and Erythrocyte sedimentation rate. However, mRNA expression levels of Dicer and Drosha were positively correlated to each other in patients with SSNHL. In this study, we demonstrated for the first time that the Dicer mRNA expression level was down-regulated in patients with SSNHL, suggesting its important role in pathobiology of SSNHL development.

Amyophatic dermatomyositis presenting as a flagellated skin eruption with positive MDA5 antibodies and thyroid cancer: a real association?

Amyopathic dermatomyositis (ADM) is characterized clinically by typical skin lesions with hypomyopathy or no muscular involvement. ADM has been recently reported to be complicated by rapidly progressive interstitial lung disease (ILD), especially in patients with positive antibodies against melanoma differentiation-associated gene 5 (MDA5). These patients may have a low risk of cancer, but no clinical, histological or laboratory markers completely specific for paraneoplastic DM have been identified to date. We report a case of flagellate erythema as the initial presentation of ADM associated with ILD, positive MDA5 antibodies and a concomitant diagnosis of thyroid cancer. We discuss the unusual clinical features and associations that make this case particularly interesting.

Dicer cleavage by calpain determines platelet microRNA levels and function in diabetes.

RATIONALE: MicroRNAs (miRNAs) are short noncoding RNA species generated by the processing of longer precursors by the ribonucleases Drosha and Dicer. Platelets contain large amounts of miRNA that are altered by disease, in particular diabetes mellitus. OBJECTIVE: This study determined why platelet miRNA levels are attenuated in diabetic individuals and how decreased levels of the platelet-enriched miRNA, miR-223, affect platelet function. METHODS AND RESULTS: Dicer levels were altered in platelets from diabetic mice and patients, a change that could be attributed to the cleavage of the enzyme by calpain, resulting in loss of function. Diabetes mellitus in human subjects as well as in mice resulted in decreased levels of platelet miR-142, miR-143, miR-155, and miR-223. Focusing on only 1 of these miRNAs, miR-223 deletion in mice resulted in modestly enhanced platelet aggregation, the formation of large thrombi and delayed clot retraction compared with wild-type littermates. A similar dysregulation was detected in platelets from diabetic patients. Proteomic analysis of platelets from miR-223 knockout mice revealed increased levels of several proteins, including kindlin-3 and coagulation factor XIII-A. Whereas, kindlin-3 was indirectly regulated by miR-223, factor XIII was a direct target and both proteins were also altered in diabetic platelets. Treating diabetic mice with a calpain inhibitor prevented loss of platelet dicer as well as the diabetes mellitus-induced decrease in platelet miRNA levels and the upregulation of miR-223 target proteins. CONCLUSIONS: Thus, calpain inhibition may be one means of normalizing platelet miRNA processing as well as platelet function in diabetes mellitus.

Interferon and interferon-inducible gene activation in patients with type 1 diabetes.

Type 1 diabetes (T1D) is an autoimmune disease that is thought to be triggered by environmental factors in genetically susceptible individuals. Enteroviruses have been mentioned as the most probable induction component of the disease. Nevertheless, the literature is controversial regarding the association of T1D with viral infection and first-line antiviral defence components, for example type I interferons (IFNs). Our aim was to test the hypothesis that an abnormality in IFN-stimulated gene patterns may cause a failure in immunological tolerance and, thereby, initiate T1D as an autoimmune disorder. We studied material from 64 T1D and 36 control subjects, divided into two age groups: <10 years and ≥10 years old. Using a relative gene expression method, we observed a lower expression of interferon-induced helicase 1 (IFIH1) and other type I IFN-induced genes in the blood cells of T1D subjects, especially subjects under 10 years old, in spite of their higher IFN levels as measured by the pSTAT1-inducing capacity of their sera. Likewise, freshly purified CpG-stimulated cells from T1D patients showed significantly lower upregulation of IFN-induced genes, that is IFIH1 and CXCL10, compared to cells from the control group. The identified dysregulation in the IFN-α-induced antiviral response in T1D patients, especially in early childhood, could be one of the factors affecting T1D development.

Robust and tissue-independent gender-specific transcript biomarkers.

CONTEXT: Correct gender assignment in humans at the molecular level is crucial in many scientific disciplines and applied areas. MATERIALS AND METHODS: Candidate gender markers were identified through supervised statistical analysis of genome wide microarray expression data from human blood samples (N = 123, 58 female, 65 male) as a training set. The potential of the markers to predict undisclosed tissue donor gender was tested on microarray data from 13 healthy and 11 cancerous human tissue collections (internal) and external datasets from samples of varying tissue origin. The abundance of some genes in the marker panel was quantified by RT-PCR as alternative analytical technology. RESULTS: We identified and qualified predictive, gender-specific transcript markers based on a set of five genes (RPS4Y1, EIF1AY, DDX3Y, KDM5D and XIST). CONCLUSION: Gene expression marker panels can be used as a robust tissue- and platform-independent predictive approach for gender determination.

Association between hepatic steatosis and hepatic expression of genes involved in innate immunity in patients with chronic hepatitis C.

BACKGROUNDS/AIMS: We investigated the association between hepatic steatosis and hepatic expression of genes involved in innate immunity, both of which are reportedly associated with resistance to peginterferon (PEG-IFN) and ribavirin combination therapy for hepatitis C virus (HCV) infection. METHODS: A total of 122 patients infected with HCV genotype 1b who underwent and completed PEG-IFN and ribavirin combination therapy were studied. Hepatic steatosis was evaluated on the basis of the liver specimen biopsied prior to antiviral therapy. The levels of mRNA of innate immunity genes (RIG-I, MDA5, LGP2, Cardif, RNF125, ISG15, and USP18) were measured by real-time polymerase chain reaction in RNA extracted from biopsied liver tissue and compared between patients with and without hepatic steatosis. RESULTS: The proportion of patients with hepatic steatosis, the hepatic expression levels of RIG-I gene, and RIG-I/Cardif and RIG-I/RNF125 ratios were significantly higher in patients in whom serum HCV RNA did not disappear throughout the treatment period. Hepatic expression of RIG-I and the ratios of RIG-I/Cardif and RIG-I/RNF125 were significantly higher in patients with steatosis than those without. CONCLUSIONS: Changes in hepatic expression of some genes involved in innate immunity were observed along with hepatic steatosis, possibly playing a mechanistic role in resistance to IFN-based therapy in patients with hepatic steatosis.

The diagnostic utility of anti-melanoma differentiation-associated gene 5 antibody testing for predicting the prognosis of Japanese patients with DM.

OBJECTIVE: Interstitial lung disease (ILD), especially rapidly progressive ILD (RPILD), is a major poor prognostic factor in patients with DM. We investigated the association of anti-melanoma differentiation-associated gene 5 (MDA5) antibody (Ab) with clinical characteristics and mortality in Japanese patients with DM. METHODS: Seventy-nine DM patients, comprising 58 classic DM and 21 clinically amyopathic DM (CADM) patients, were enrolled. Serum Abs were screened by immunoprecipitation assays, and an immunosorbent assay (ELISA) was used for MDA5. The relationships of clinical characteristics and mortality with each Ab were investigated. RESULTS: Anti-MDA5 Ab was detected in 17 patients. Anti-clinically amyopathic DM 140 kDa polypeptide Abs (anti-CADM-140 Abs) were found in 16 of the 17 anti-MDA5 Ab(+) patients. Skin ulcers, palmar papules, CADM, RPILD and mediastinal emphysema were widely distributed in anti-MDA5 Ab(+) patients. Mortality at 6 months as well as 5 years was also significantly higher in anti-MDA5 Ab(+) patients than in anti-MDA5 Ab(-) patients. In a multivariable Cox regression analysis, mortality was independently associated with anti-MDA5 Ab (relative hazard 6.33; 95% CI 1.43, 28.0). All of the deaths in anti-MDA5 Ab(+) patients were attributed to respiratory failure of RPILD; however, RPILD did not worsen in any of the anti-MDA5 Ab(+) patients who survived the first 6 months. CONCLUSION: The presence of anti-MDA5 Ab identifies the characteristic skin, musculoskeletal, pulmonary and prognostic features in patients with DM. In addition, anti-MDA5 Ab seems to predict a group of patients with CADM-complicated fatal RPILD.

RNA helicase encoded by melanoma differentiation-associated gene 5 is a major autoantigen in patients with clinically amyopathic dermatomyositis: Association with rapidly progressive interstitial lung disease.

OBJECTIVE: To identify the autoantigen recognized by the autoantibody that is associated with clinically amyopathic dermatomyositis (C-ADM) and rapidly progressive interstitial lung disease (ILD). METHODS: An anti-CADM-140 antibody-positive prototype serum sample was used to screen a HeLa cell-derived complementary DNA (cDNA) library. Selected cDNA clones were further evaluated by immunoprecipitation of their in vitro-transcribed and in vitro-translated products using anti-CADM-140 antibody-positive and anti-CADM-140 antibody-negative sera. The lysates of COS-7 cells transfected with the putative antigen were similarly tested. An enzyme-linked immunosorbent assay (ELISA) to detect the anti-CADM-140 antibody was established using a recombinant CADM-140 antigen, and its specificity and sensitivity for C-ADM and rapidly progressive ILD were assessed in 294 patients with various connective tissue diseases. RESULTS: By cDNA library screening and immunoprecipitation of in vitro-transcribed and in vitro-translated products, we obtained a cDNA clone encoding melanoma differentiation-associated gene 5 (MDA-5). The anti-CADM-140 antibodies in patients' sera specifically reacted with MDA-5 protein expressed in cells transfected with full-length MDA-5 cDNA, confirming the identity of MDA-5 as the CADM-140 autoantigen. The ELISA, using recombinant MDA-5 protein as the antigen, showed an analytical sensitivity of 85% and analytical specificity of 100%, in comparison with the "gold standard" immunoprecipitation assay, and was useful for identifying patients with C-ADM and/or rapidly progressive ILD. CONCLUSION: Given that RNA helicase encoded by MDA-5 is a critical molecule involved in the innate immune defense against viruses, viral infection may play an important role in the pathogenesis of C-ADM and rapidly progressive ILD. Moreover, our ELISA using recombinant MDA-5 protein makes detection of the anti-CADM-140 antibody routinely available.

Genomic profiling of circulating plasma RNA for the analysis of cancer.

BACKGROUND: The blood of cancer patients is known to contain fragments of RNA released from the tumor. The application of genomic profiling techniques to plasma RNA may allow the unbiased selection of cancer markers in the blood, but the informative value of genomic profiling of plasma RNA is currently unknown. METHODS: We used cDNA microarray hybridization to perform genomic profiling of plasma RNA from colorectal cancer (CRC) patients and from healthy donors. From a list of 40 genes differentially upregulated in cancer patients, we randomly selected 4 genes for further characterization. These 4 markers were analyzed by quantitative reverse-transcription PCR in a wide set of samples including paired samples from the same CRC patients before and after surgical resection of the tumor. RESULTS: Three of the selected markers - EPAS1, UBE2D3, and KIAA0101 - were confirmed by PCR to be significantly increased in cancer compared to healthy donors. Importantly, 2 of the markers, EPAS1 and UBE2D3, showed a significant decrease after surgery, returning to the levels of healthy donors. Finally, supervised class prediction using these 3 markers correctly (77%) assigned presurgery samples to the CRC group and assigned postsurgery samples from the same patients to the healthy group. CONCLUSIONS: Our findings demonstrate the usefulness of gene expression profiling of circulating plasma RNA to find cancer markers of potential clinical value.