125 research outputs found
A Novel Predictor Tool of Biochemical Recurrence after Radical Prostatectomy Based on a Five-MicroRNA Tissue Signature
Within five to ten years after radical prostatectomy (RP), approximately 15-34% of prostate cancer (PCa) patients experience biochemical recurrence (BCR), which is defined as recurrence of serum levels of prostate-specific antigen >0.2 µg/L, indicating probable cancer recurrence. Models using clinicopathological variables for predicting this risk for patients lack accuracy. There is hope that new molecular biomarkers, like microRNAs (miRNAs), could be potential candidates to improve risk prediction. Therefore, we evaluated the BCR prognostic capability of 20 miRNAs, which were selected by a systematic literature review. MiRNA expressions were measured in formalin-fixed, paraffin-embedded (FFPE) tissue RP samples of 206 PCa patients by RT-qPCR. Univariate and multivariate Cox regression analyses were performed, to assess the independent prognostic potential of miRNAs. Internal validation was performed, using bootstrapping and the split-sample method. Five miRNAs (miR-30c-5p/31-5p/141-3p/148a-3p/miR-221-3p) were finally validated as independent prognostic biomarkers. Their prognostic ability and accuracy were evaluated using C-statistics of the obtained prognostic indices in the Cox regression, time-dependent receiver-operating characteristics, and decision curve analyses. Models of miRNAs, combined with relevant clinicopathological factors, were built. The five-miRNA-panel outperformed clinically established BCR scoring systems, while their combination significantly improved predictive power, based on clinicopathological factors alone. We conclude that this miRNA-based-predictor panel will be worth to be including in future studies
Circular RNAs in Clear Cell Renal Cell Carcinoma: Their Microarray-Based Identification, Analytical Validation, and Potential Use in a Clinico-Genomic Model to Improve Prognostic Accuracy
Circular RNAs (circRNAs) may act as novel cancer biomarkers. However, a genome-wide evaluation of circRNAs in clear cell renal cell carcinoma (ccRCC) has yet to be conducted. Therefore, the objective of this study was to identify and validate circRNAs in ccRCC tissue with a focus to evaluate their potential as prognostic biomarkers. A genome-wide identification of circRNAs in total RNA extracted from ccRCC tissue samples was performed using microarray analysis. Three relevant differentially expressed circRNAs were selected (circEGLN3, circNOX4, and circRHOBTB3), their circular nature was experimentally confirmed, and their expression-along with that of their linear counterparts-was measured in 99 malignant and 85 adjacent normal tissue samples using specifically established RT-qPCR assays. The capacity of circRNAs to discriminate between malignant and adjacent normal tissue samples and their prognostic potential (with the endpoints cancer-specific, recurrence-free, and overall survival) after surgery were estimated by C-statistics, Kaplan-Meier method, univariate and multivariate Cox regression analysis, decision curve analysis, and Akaike and Bayesian information criteria. CircEGLN3 discriminated malignant from normal tissue with 97% accuracy. We generated a prognostic for the three endpoints by multivariate Cox regression analysis that included circEGLN3, circRHOBT3 and linRHOBTB3. The predictive outcome accuracy of the clinical models based on clinicopathological factors was improved in combination with this circRNA-based signature. Bootstrapping as well as Akaike and Bayesian information criteria confirmed the statistical significance and robustness of the combined models. Limitations of this study include its retrospective nature and the lack of external validation. The study demonstrated the promising potential of circRNAs as diagnostic and particularly prognostic biomarkers in ccRCC patients
Congenital Lymphoedema, Bronchiectasis And Seizure: Case Report
A l0-year-old girl with facial anomalies, mental retardation, peripheral lymphoedema, convulsions, cerebral cortical dysgenetic changes, bronchiectasis and chronic sinusitis is presented. She had features of both yellow nail syndrome and Hennekam syndrome. We think that our case might be a new congenital lymphoedema syndrome or an
intermediate form between these syndromes. East African Medical Journal Vol. 85 (3) 2008: pp. 145-14
Cooperative Effect of miR-141-3p and miR-145-5p in the Regulation of Targets in Clear Cell Renal Cell Carcinoma
Background Due to the poor prognosis for advanced renal cell carcinoma (RCC),
there is an urgent need for new therapeutic targets and for prognostic markers
to identify high risk tumors. MicroRNAs (miRNAs) are frequently dysregulated
in tumors, play a crucial role during carcinogenesis and therefore might be
promising new biomarkers. In previous studies, we identified miR-141-3p and
miR-145-5p to be downregulated in clear cell RCC (ccRCC). Our objective was to
investigate the functional association of these miRNAs, focusing on the
cooperative regulation of new specific targets and their role in ccRCC
progression. Methods The effect of miR-141-3p and miR-145-5p on cell migration
was examined by overexpression in 786-O cells. New targets of both miRNAs were
identified by miRWalk, validated in 786-O and ACHN cells and additionally
characterized in ccRCC tissue on mRNA and protein level. Results In functional
analysis, a tumor suppressive effect of miR-141-3p and miR-145-5p by
decreasing migration and invasion of RCC cells could be shown. Furthermore,
co-overexpression of the miRNAs seemed to result in an increased inhibition of
cell migration. Both miRNAs were recognized as post-transcriptional regulators
of the targets EAPP, HS6ST2, LOX, TGFB2 and VRK2. Additionally, they showed a
cooperative effect again as demonstrated by a significantly increased
inhibition of HS6ST2 and LOX expression after simultaneous overexpression of
both miRNAs. In ccRCC tissue, LOX mRNA expression was strongly increased
compared to normal tissue, allowing also to distinguish between non-metastatic
and already metastasized primary tumors. Finally, in subsequent tissue
microarray analysis LOX protein expression showed a prognostic relevance for
the overall survival of ccRCC patients. Conclusion These results illustrate a
jointly strengthening effect of the dysregulated miR-141-3p and miR-145-5p in
various tumor associated processes. Focusing on the cooperative effect of
miRNAs provides new opportunities for the development of therapeutic
strategies and offers novel prognostic and diagnostic capabilities
Renal cell neoplasias: reversion-inducing cysteine-rich protein with Kazal motifs discriminates tumor subtypes, while extracellular matrix metalloproteinase inducer indicates prognosis
BACKGROUND: Matrix metalloproteinases can promote invasion and metastasis, which are very frequent in renal cell carcinoma even at the time of diagnosis. Knowing the reversion-inducing cysteine-rich protein with Kazal motifs (RECK) as an inhibitor of matrix metalloproteinases and the extracellular matrix metalloproteinase inducer (EMMPRIN) protein as inducer, we aimed to determine their expression, localization and possible antagonistic action in the pathogenesis and progression of renal cell tumors in a retrospective study. METHODS: Tumor and adjacent normal tissues of 395 nephrectomized patients were immunostained for RECK and EMMPRIN on a tissue microarray. RESULTS: RECK strongly decreased in renal cell carcinoma compared to normal counterparts (Wilcoxon signed rank test, P < 0.001), and it discriminated tumor entities showing the highest expression in oncocytomas. EMMPRIN, however, could be significantly correlated to pT stage and Fuhrman grading (Spearman’s correlation coefficient r(s) = 0.289 and r(s) = 0.382, respectively). Higher expression of EMMPRIN was associated with decreased overall survival in Kaplan-Meier analysis (P < 0.001), and the EMMPRIN level could independently predict survival for cases without metastasis and involvement of lymph nodes. Decreased RECK expression was confirmed by Western blotting in tissue of eight normal/tumor matches of patients after radical nephrectomy, whereas the EMMPRIN pattern appeared to be heterogeneous. CONCLUSIONS: We propose RECK down regulation in renal cell carcinoma to be an early event that facilitates tumor formation and progression. EMMPRIN, however, as a prognostic tumor marker, increases only when aggressiveness is proceeding and could add an additional step to invasive properties of renal cell carcinoma
miR-199a-3p and miR-214-3p improve the overall survival prediction of muscle- invasive bladder cancer patients after radical cystectomy
To improve the clinical decision-making regarding further treatment management
and follow-up scheduling for patients with muscle-invasive bladder cancer
(MIBC) after radical cystectomy (RC), a better prediction accuracy of
prognosis for these patients is urgently needed. The objective of this study
was to evaluate the validity of differentially expressed microRNAs (miRNAs)
based on a previous study as prognostic markers for overall survival (OS)
after RC in models combined with clinicopathological data. The expression of
six miRNAs (miR-100-5p, miR-130b-3p, miR-141-3p, miR-199a-3p, miR-205-5p, and
miR-214-3p) was measured by RT-qPCR in formalin-fixed, paraffin-embedded
tissue samples from 156 MIBC patients who received RC in three urological
centers. Samples from 2000 to 2013 were used according to their tissue
availability, with follow-up until June 2016. The patient cohort was randomly
divided into a training (n = 100) and test set (n = 56). Seventy-three samples
from adjacent normal tissue were used as controls. Kaplan–Meier, univariate
and multivariate Cox regression, and decision curve analyses were carried out
to assess the association of clinicopathological variables and miRNAs to OS.
Both increased (miR-130b-3p and miR-141-3p) and reduced (miR-100-5p, miR-199a-
3p, and miR-214-3p) miRNA expressions were found in MIBC samples in comparison
to nonmalignant tissue samples (P < 0.0001). miR-199a-3p and miR-214-3p were
independent markers of OS in Cox regression models with the significant
clinicopathological variables age, tumor status, and lymph node status. The
prediction model with the clinicopathological variables was improved by these
two miRNAs in both sets. The predictive benefit was confirmed by decision
curve analysis. In conclusion, the inclusion of both miRNAs into models based
on clinical data for the outcome prediction of MIBC patients after RC could be
a valuable approach to improve prognostic accuracy
Integrated microRNA and mRNA Signature Associated with the Transition from the Locally Confined to the Metastasized Clear Cell Renal Cell Carcinoma Exemplified by miR-146-5p
Background MicroRNAs (miRNAs) regulate gene expression by interfering
translation or stability of target transcripts. This interplay between miRNA
and their mRNA has been proposed as an important process in cancer development
and progression. We have investigated molecular networks impacted by predicted
mRNA targets of differentially expressed miRNAs in patients with clear cell
renal cell carcinoma (ccRCC) diagnosed with or without metastasis. Material
and Methods miRNA and mRNA microarray expression profiles derived from primary
ccRCC from patients with (16 samples) or without diagnosed metastasis (22
samples) were used to identify anti-correlated miRNA-mRNA interaction in
ccRCC. For this purpose, Ingenuity pathway analysis microRNA Target Filter,
which enables prioritization of experimentally validated and predicted mRNA
targets was used. By applying an expression pairing tool, the analysis was
focused on targets exhibiting altered expression in our analysis, finding
miRNAs and their target genes with opposite or same expression. The resulting
identified interactions were revalidated by RT-qPCR in another cohort of ccRCC
patients. A selection of the predicted miRNA-mRNA interactions was tested by
functional analyses using miRNA knockdown and overexpression experiments in
renal cancer cell lines. Results Among the significantly differentially
expressed miRNAs, we have identified three miRNAs (miR-146a-5p, miR-128a-3p,
and miR-17-5p) that were upregulated in primary tumors from patients without
metastasis and downregulated in primary tumors from patients with metastasis.
We have further identified mRNA targets, which expression were inversely
correlated to these 3 miRNAs, and have been previously experimentally
demonstrated in cancer setting in humans. Specifically, we showed that
CXCL8/IL8, UHRF1, MCM10, and CDKN3 were downregulated and targeted by miR-
146a-5p. The interaction between miR-146a-5p and their targets CXCL8 and UHRF1
was validated in cell culture experiments. Conclusions We identified novel
target genes of dysregulated miRNAs, which are involved in the transition from
primary RCC without metastases into tumors generating distant metastasis
Piwi-interacting RNAs as novel prognostic markers in clear cell renal cell carcinomas
Background Piwi-interacting RNAs (piRNAs) are small RNAs of 27–30 nucleotides
mapping to transposons or clustering in repeat genomic regions. Preliminary
studies suggest an important role in cancerogenesis. This study is the first
one investigating their prognostic impact in clear cell renal cell cancer
(ccRCC) patients. Methods Three piRNAs (piR-30924, piR-57125, and piR-38756)
selected on the basis of initial piRNA microarray analyses were determined
using RT-qPCR in non-metastatic (n = 76) and metastatic (n = 30) ccRCC tissue
at the time of nephrectomy in comparison to normal renal tissue (n = 77) and
tissue from distant ccRCC metastases (n = 13). Primary clinical end points
were recurrence-free and overall survival. Results piR-57125 showed lower
expression in metastatic than in non-metastatic tumors, whereas the expression
of piR-30924 and piR-38756 increased in metastatic tumors. The higher
expression of piR-30924 and piR-38756 as well as the lower expression of
piR-57125 in metastatic primary tumors were significantly associated with
tumor recurrence and overall survival. Multivariate Cox regression analyses
revealed both piR-30924 and piR-57125 as independent prognostic predictors.
This impact was even more pronounced in non-metastatic patients. Conclusions
This study demonstrates that the expression levels of these piRNAs in primary
non-metastatic and metastatic ccRCC tissue can serve as potential prognostic
biomarkers in combination with clinicopathological factors
Instability of circular RNAs in clinical tissue samples impairs their reliable expression analysis using RT-qPCR: from the myth of their advantage as biomarkers to reality
Background: Circular RNAs (circRNAs) are a new class of RNAs with medical significance. Compared to that of linear mRNA transcripts, the stability of circRNAs against degradation owing to their circular structure is considered advantageous for their use as biomarkers. As systematic studies on the stability of circRNAs depending on the RNA integrity, determined as RNA integrity number (RIN), in clinical tissue samples are lacking, we have investigated this aspect in the present study under model and clinical conditions.
Methods: Total RNA isolated from kidney cancer tissue and cell lines (A-498 and HEK-293) with different RIN after thermal degradation was used in model experiments. Further, RNA isolated from kidney cancer and prostate cancer tissue collected under routine surgical conditions, representing clinical samples with RIN ranging from 2 to 9, were examined. Quantitative real-time reverse-transcription polymerase chain reaction (RT-qPCR) analysis of several circRNAs (circEGLN3, circRHOBTB3, circCSNK1G3, circRNA4, and circRNA9), their corresponding linear counterparts, tissue-specific reference genes, and three microRNAs (as controls) was performed. The quantification cycles were converted into relative quantities and normalized to the expression of specific reference genes for the corresponding tissue. The effect of RIN on the expression of different RNA entities was determined using linear regression analysis, and clinical samples were classified into two groups based on RIN greater or lesser than 6.
Results: The results of model experiments and clinical sample analyses showed that all relative circRNA expression gradually decreased with reduction in RIN values. The adverse effect of RIN was partially compensated after normalizing the data and limiting the samples to only those with RIN values > 6.
Conclusions: Our results suggested that circRNAs are not stable in clinical tissue samples, but are subjected to degradative processes similar to mRNAs. This has not been investigated extensively in circRNA expression studies, and hence must be considered in future for obtaining reliable circRNA expression data. This can be achieved by applying the principles commonly used in mRNA expression studies
miR-9-5p in Nephrectomy Specimens is a Potential Predictor of Primary Resistance to First-Line Treatment with Tyrosine Kinase Inhibitors in Patients with Metastatic Renal Cell Carcinoma
Approximately 20-30% of patients with metastatic renal cell carcinoma (mRCC) in first-line treatment with tyrosine kinase inhibitors (TKIs) do not respond due to primary resistance to this drug. At present, suitable robust biomarkers for prediction of a response are not available. Therefore, the aim of this study was to evaluate a panel of microRNAs (miRNAs) in nephrectomy specimens for use as predictive biomarkers for TKI resistance. Archived formalin-fixed, paraffin embedded nephrectomy samples from 60 mRCC patients treated with first-line TKIs (sunitinib, n = 51; pazopanib, n = 6; sorafenib, n = 3) were categorized into responders and non-responders. Using the standard Response Evaluation Criteria in Solid Tumors, patients with progressive disease within 3 months after the start of treatment with TKI were considered as non-responders and those patients with stable disease and complete or partial response under the TKI treatment for at least 6 months as responders. Based on a miRNA microarray expression profile in the two stratified groups of patients, seven differentially expressed miRNAs were validated using droplet digital reverse-transcription quantitative real-time polymerase chain reaction (RT-qPCR) assays in the two groups. Receiver operating characteristic curve analysis and binary logistic regression of response prediction were performed. MiR-9-5p and miR-489-3p were able to discriminate between the two groups. MiR-9-5p, as the most significant miRNA, improved the correct prediction of primary resistance against TKIs in comparison to that of conventional clinicopathological variables. The results of the decision curve analyses, Kaplan-Meier analyses and Cox regression analyses confirmed the potential of miR-9-5p in the prediction of response to TKIs and the prediction of progression-free survival after the initiation of TKI treatment
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