Cell-Free SHOX2 DNA Methylation in Blood as a Molecular Staging Parameter for Risk Stratification in Renal Cell Carcinoma Patients: A Prospective Observational Cohort Study.

BACKGROUND: Novel targeted treatments and immunotherapies have substantially changed therapeutic options for advanced and metastatic renal cell carcinomas (RCCs). However, accurate diagnostic tests for the identification of high-risk patients are urgently needed. Here, we analyzed SHOX2 mRNA expression in RCC tissues and SHOX2 gene body methylation quantitatively in circulating cell-free DNA (ccfDNA) and RCC tissues with regard to risk stratification. METHODS: The clinical performance of SHOX2 methylation was tested retrospectively and prospectively in a training and testing cohort of RCC tissue samples (n = 760 in total). SHOX2 mRNA expression analysis was included in the training cohort. In matched blood plasma samples from the testing cohort (n = 100), we prospectively examined the capability of pretherapeutic quantitative SHOX2 ccfDNA methylation to assess disease stage and identify patients at high risk of death. RESULTS: SHOX2 gene body methylation was positively correlated with mRNA expression in RCC tissues (training cohort: Spearman ρ = 0.23, P < 0.001). SHOX2 methylation in tissue and plasma strongly correlated with an advanced disease stage (training cohort: ρ = 0.28, P < 0.001; testing cohort/tissue: ρ = 0.40, P < 0.001; testing cohort/plasma: ρ = 0.34, P = 0.001) and risk of death after initial partial or radical nephrectomy [training cohort: hazard ratio (HR) = 1.40 (95% CI, 1.24-1.57), P < 0.001; testing cohort/tissue: HR = 1.16 (95% CI, 1.07-1.27), P = 0.001; testing cohort/plasma: HR = 1.50 (95% CI, 1.29-1.74), P < 0.001]. CONCLUSIONS: Pretherapeutic SHOX2 ccfDNA methylation testing allows for the identification of RCC patients at high risk of death after nephrectomy. These patients might benefit from an adjuvant treatment or early initiation of a palliative treatment.

Influence of Body Mass Index on Clinical Outcome Parameters, Complication Rate and Survival after Radical Cystectomy: Evidence from a Prospective European Multicentre Study.

Background/Aims/Objectives: To evaluate the influence of body mass index (BMI) on complications and oncological outcomes in patients undergoing radical cystectomy (RC). METHODS: Clinical and histopathological parameters of patients have been prospectively collected within the "PROspective MulticEnTer RadIcal Cystectomy Series 2011". BMI was categorized as normal weight (<25 kg/m2), overweight (≥25-29.9 kg/m2) and obesity (≥30 kg/m2). The association between BMI and clinical and histopathological endpoints was examined. Ordinal logistic regression models were applied to assess the influence of BMI on complication rate and survival. RESULTS: Data of 671 patients were eligible for final analysis. Of these patients, 26% (n = 175) showed obesity. No significant association of obesity on tumour stage, grade, lymph node metastasis, blood loss, type of urinary diversion and 90-day mortality rate was found. According to the -American Society of Anesthesiologists score, local lymph node (NT) stage and operative case load patients with higher BMI had significantly higher probabilities of severe complications 30 days after RC (p = 0.037). The overall survival rate of obese patients was superior to normal weight patients (p = 0.019). CONCLUSIONS: There is no evidence of correlation between obesity and worse oncological outcomes after RC. While obesity should not be a parameter to exclude patients from cystectomy, surgical settings need to be aware of higher short-term complication risks and obese patients should be counselled -accordingly.

The knockdown of the mediator complex subunit MED30 suppresses the proliferation and migration of renal cell carcinoma cells.

BACKGROUND: The mediator complex consists of 33 subunits and plays a central role in transcription. Studies have already described the involvement of individual subunits, especially in carcinogenesis. With regard to the subunit MED30, this has, so far, only been confirmed in gastric and breast carcinoma. The role of MED30 in urological tumours is unknown. MATERIALS AND METHODS: First, a database analysis using cBioPortal was performed for the mRNA expression and survival analysis of MED30 in clear cell renal cell carcinoma (ccRCC) and papillary RCC (pRCC). The immunohistochemical analysis (IHC) against MED30 was performed on tissue microarrays (TMA), with benign, ccRCC, pRCC samples, and ccRCC-metastases. Intensity evaluation was performed using the IRS (Immunoreactive Score). The ccRCC cell lines ACHN and A-498 were used for the functional investigation of proliferation, migration, and invasion after the knockdown of MED30 by siRNA. RESULTS: In a database analysis by cBioPortal, it was shown that mRNA overexpression of MED30 in the pRCC was significantly associated with a poorer overall survival and progression-free survival. In the IHC, pRCC showed the highest level of MED30 expression, unfortunately without significant results in the survival analysis. The knockdown of MED30 resulted in a significant decrease in proliferation, migration, and invasion in ccRCC. CONCLUSION: In summary, MED30 seems to be involved in the progression of the RCC.

Identification of the dopamine transporter SLC6A3 as a biomarker for patients with renal cell carcinoma.

BACKGROUND: Clear cell renal cell carcinoma (ccRCC) is among the most common human malignancies. METHODS: In order to provide better understanding of the molecular biology of ccRCC and to identify potential diagnostic/prognostic biomarker and therapeutic targets, we utilized a microarray to profile mRNA expression of corresponding normal and malignant renal tissues. Real-time PCR, Western Blot and immunohistochemistry were applied to study the expression of candidate biomarkers. ccRCC cell lines were treated with sertraline to inhibit the dopamine transporter SLC6A3. RESULTS: Differential expression of fourteen mRNAs, yet not studied in ccRCC in depth, was confirmed using qPCR (upregulation: SLC6A3, NPTX2, TNFAIP6, NDUFA4L2, ENPP3, FABP6, SPINK13; downregulation: FXYD4, SLC12A1, KNG1, NPHS2, SLC13A3, GCGR, PLG). Up-/downregulation was also confirmed for FXYD4, KNG1, NPTX2 and SLC12A1 by Western Blot on the protein level. In contrast to the mRNA expression, protein expression of the dopamine transporter SLC6A3 was lower in ccRCC compared to normal renal tissue. Immunohistochemistry indicated that this decrease was due to higher concentrations of SLC6A3 in the proximal tubules. Immunohistochemical analyses further demonstrated that high SLC6A3 expression in ccRCC tissue was correlated with a shorter period of recurrence-free survival following surgery. Treatment of ccRCC cells with the SLC6A3 inhibitor sertraline induced dose-dependent cell-death. CONCLUSION: Our study identified several novel biomarkers with diagnostic potential and further investigations on sertraline as therapeutic agent in ccRCC patients are warranted.

Circulating serum miRNA (miR-367-3p, miR-371a-3p, miR-372-3p and miR-373-3p) as biomarkers in patients with testicular germ cell cancer.

PURPOSE: Classic serum tumor markers (human chorionic gonadotropin, α1-fetoprotein and lactate dehydrogenase) have an important role in managing testicular germ cell tumor. Since only 60% of all patients with testicular germ cell tumor have elevations of these markers, there is a need for new biomarkers with greater sensitivity/specificity. miRNAs are deregulated in cancer and could serve as noninvasive serum biomarkers. We explored the role of serum miRNAs as a novel biomarker in patients with testicular germ cell tumor. MATERIALS AND METHODS: Total RNA was isolated from serum. miRNA levels were quantified by quantitative real-time polymerase chain reaction. We assessed the miRNAs miR-302a-3p, 302b-3p, 302c-3p, 367-3p, 371a-3p, 372-3p and 373-3p in a subcohort of 30 patients with testicular germ cell tumor and 18 healthy subjects. Validation was performed in 76 patients treated with inguinal exploration due to suspicion of testicular germ cell tumor, of whom 59 had cancer and 17 had benign disease, and in 84 healthy male subjects. RESULTS: Serum miR-367-3p, 371a-3p, 372-3p and 373-3p levels were significantly increased in patients with testicular germ cell tumor compared to healthy individuals and patients with nonmalignant testicular disease. In particular miR-371a-3p allowed for sensitive (84.7%) and specific (99%) identification of patients with testicular germ cell tumor, thus, outperforming human chorionic gonadotropin or α1-fetoprotein testing. Furthermore, miR-367-3p was increased in nonseminoma compared to seminoma cases. Serum miRNA levels were increased in patients with advanced local stage and metastasis. In 9 patients with localized (clinical stage 1A) testicular germ cell tumor serum miR-371a-3p levels decreased postoperatively, indicating tumor specific release. CONCLUSIONS: miR-371a-3p allows for better identification of testicular germ cell tumor than α1-fetoprotein and human chorionic gonadotropin. It could be helpful for clinically managing testicular germ cell tumor, especially for monitoring surveillance therapy and residual disease after chemotherapy.

A Multi-institutional Pooled Analysis Demonstrates That Circulating miR-371a-3p Alone is Sufficient for Testicular Malignant Germ Cell Tumor Diagnosis.

BACKGROUND: Circulating microRNAs have clear potential for improving malignant germ-cell-tumor (MGCT) diagnosis. Here, we address the central issue of whether measurement of a single microRNA is sufficient for detecting testicular MGCTs, or whether there is added benefit in quantifying other members of the 4-microRNA panel previously identified (miR-371a-3p/miR-372-3p/miR-373-3p and miR-367-3p). PATIENTS AND METHODS: We performed a pooled analysis of available published raw data where all 4 panel miRNAs had been assessed using pre-amplification PCR technology (4 studies; total 329 patients). Two studies using identical methodology (and identical normalization using endogenous miR-30b-5p) were used in the discovery phase (n = 51 patients: 17 MGCT, 34 controls). The 2 other studies (n = 278 patients: 140 MGCT, 138 controls), which assessed the same test panel but with different normalization approaches (endogenous miR-93-5p, exogenous cel-miR-39-3p), were used for the validation phase. We derived sensitivity, specificity, positive- and negative-predictive-values (PPV/NPV) for the detection thresholds that maximised the Youden Index (YI). RESULTS: In the discovery-phase, the YI was 0.97 for miR-371a-3p (sensitivity = 1, specificity = 0.97), 0.71 (miR-367-3p), 0.68 (miR-372-3p), and 0.50 (miR-373-3p). These findings were confirmed in the validation-phase, with YI of 0.75 for miR-371a-3p (sensitivity = 0.90, specificity 0.85), 0.55 (miR-367-3p), 0.47 (miR-372-3p), and 0.51 (miR-373-3p). Importantly, no combination of markers added additional diagnostic benefit to miR-371a-3p alone, in either the discovery or the validation phase. CONCLUSION: Quantifying circulating miR-371a-3p alone is sufficient for testicular MGCT diagnosis. PCR measurement of this single miRNA marker will be more cost-effective and easier to interpret, facilitating future incorporation into routine clinical practice.

Evaluation of Serum Biomarkers (FGF-2, HGF, MIF and PTN) in Patients With Testicular Germ Cell Cancer.

BACKGROUND/AIM: FGF-2, HGF, MIF and PTN have been suggested as biomarkers for testicular germ cell cancer patients in earlier studies. Our study was designed to validate these potential novel tumor markers. MATERIALS AND METHODS: Serum FGF-2, HGF, MIF and PTN levels were analysed using an ELISA technique in a screening cohort of 20 testicular germ cell cancer patients and 10 healthy men. MIF levels were measured in a validation cohort of 84 patients with testicular cancer, 24 with non-malignant testicular tumors and 64 healthy men. RESULTS: Serum FGF-2, HGF and PTN levels did not differ in cancer patients and healthy males within the screening cohort, whereas MIF was significantly increased among cancer patients. Within the validation cohort, a modest but insignificant increase of serum MIF was observed in TGCT patients compared to healthy men. MIF levels were not correlated with adverse clinical-pathological parameters. CONCLUSION: FGF-2, HGF, MIF and PTN are not suitable as non-invasive biomarkers for testicular germ cell cancer patients.

The Mediator complex subunit MED15, a promoter of tumour progression and metastatic spread in renal cell carcinoma.

BACKGROUND/OBJECTIVE: MED15 is a part of the multiprotein Mediator complex which is involved in the transcription of polymerase (Pol) II-dependent genes. Several studies in this field have reported altered expressions of distinct subunits in human malignancy. However, the role of MED15 in renal cell carcinoma (RCC) has not be investigated yet. METHODS: First, we performed an RNA expression and survival analysis of MED15 in RCC by using the database cBioPortal. To confirm these data on the protein level, we executed immunohistochemical (IHC) staining against MED15 on a tissue microarray containing 184 samples of the most common subtypes of the tumour at the various stages. Further, we performed functional analysis including proliferation, migration, and invasion assays on the RCC cell lines A-498 and ACHN following the siRNA-mediated MED15 knockdown. RESULTS: On the mRNA level, higher expression of MED15 was associated with worse patient survival rates. IHC staining validated this tendency, unfortunately the results were not significant. However, supporting this tendency, in vitro-assays showed a significant decrease in proliferation, migration, and invasion after knockdown of MED15. CONCLUSION: The research concludes that MED15 does seem to play a tumour promoting role in the progression and metastatic spread of renal cell carcinoma.

The knockdown of the Mediator complex subunit MED15 restrains urothelial bladder cancer cells' malignancy.

The Mediator complex, a multi-subunit protein complex, plays an integral role in regulating transcription. Genetic alterations of the mediator subunit 15 (MED15) in separate tumor entities have been described previously. However, till now, not much is known about the role of MED15 in urothelial bladder cancer (BCa). Using cBioPortal, database analysis was executed for the mRNA expression and survival analysis of MED15 in BCa. Immunohistochemistry (IHC) analysis against MED15 was performed on tissue microarrays with 18 benign, 126 BCa, and 38 metastases samples. The intensity evaluation was performed using a staining intensity score from 0 to 3 and associated with clinicopathological data. The BCa cell lines T24 and TCCSUP were used for the functional investigation. After the MED15 knockdown by small interfering (si)RNA, cell proliferation, migration and invasion were investigated. On the mRNA level, only a low number of alterations (2%) was found for MED15 in BCa. Due to the small count of events, there were no significant differences or tendencies in survival. For IHC, MED15 was found to have a higher expression in non-muscle invasive BCa compared with benign and muscle invasive BCa. For survival analysis, no significant differences between samples with or without overexpression of MED15 were found. In the functional analysis, proliferation, migration, and invasion were significantly reduced in BCa-cells following the transient siRNA-mediated MED15 knockdown. In summary, MED15 appears to play a role in the tumor parameters proliferation, migration, and invasion in BCa, but further investigations are necessary.

The Contrasting Role of the Mediator Subunit MED30 in the Progression of Bladder Cancer.

BACKGROUND/AIM: The Mediator complex is a key regulator of gene transcription, and several studies have demonstrated altered expression of particular subunits in diverse human diseases, especially cancer. To date, nothing is known about the role of MED30 in bladder cancer. MATERIALS AND METHODS: We, therefore, performed an RNA expression and survival analysis of the subunit MED30 in 537 samples of bladder cancer by using the database cBioPortal. To validate these data on the protein level, we practiced immunohistochemical staining against MED30 on a tissue microarray containing 210 samples of all tumour stages and performed survival analyses. For functional analysis, the siRNA-mediated knockdown of MED30 was performed in the cell lines T24 and TCCSUP followed by proliferation, migration, and invasion assays. RESULTS: On the mRNA and protein levels, higher expression of MED30 is associated with better patient survival. In accordance with this, advanced T- and N-stages showed lower expression of MED30. In contrast, knockdown of MED30 led to reduction of the tumour parameters proliferation, migration, and invasion in the BCa cell lines. CONCLUSION: MED30 appears to be integrated in the progression of the urothelial tumour in the bladder.

Mediator Complex Subunit MED1 Protein Expression Is Decreased during Bladder Cancer Progression.

Introduction: Bladder cancer (BCa) is among the most frequent cancer entities and relevantly contributes to cancer-associated deaths worldwide. The multi-protein Mediator complex is a central regulator of the transcriptional machinery of protein-coding genes and has been described to be altered in several malignancies. MED1, a subunit of the tail module, was described to negatively modulate expression of metastasis-related genes and to be downregulated in melanoma and lung cancer. In contrast, MED1 hyperactivity was described in breast and prostate cancer, likely due its function as a hub for nuclear hormone receptors. So far, only little is known about the function of the Mediator complex in BCa. The aim of this study was therefore to investigate the role of MED1 in BCa as a prognostic biomarker and a biomarker of disease progression. Methods: The protein expression of MED1 was assessed by immunohistochemistry (IHC) on tissue microarrays from 224 patients: benign urothelium n = 31, non-muscle invasive BCa (pTis, pT1) n = 72, and muscle invasive BCa (pT2-T4) n = 121. Comprehensive clinicopathological information including follow-up were available. Quantification of MED1 protein expression was evaluated by the semiquantitative image analysis program Definiens. Results: MED1 expression significantly decreased during BCa progression from benign urothelium to advanced BCa. Muscle invasion, the crucial step in BCa progression, was associated with low MED1 protein expression. Accordingly, decreased MED1 expression was found in primary BCa samples with positive lymphonodal status and distant metastases. Furthermore, cancer-specific survival was significantly worse in the group of low MED1 expression. Conclusion: Our findings show that the downregulation of MED1 is associated with muscle invasion, metastatic spread, and shorter overall survival in BCa.

MED15 overexpression in prostate cancer arises during androgen deprivation therapy via PI3K/mTOR signaling.

Androgen deprivation therapy (ADT) is the main therapeutic option for advanced prostate cancer (PCa). After initial regression, most tumors develop into castration-resistant PCa (CRPC). Previously, we found the Mediator complex subunit MED15 to be overexpressed in CRPC and to correlate with clinical outcome. Therefore, we investigated whether MED15 is implicated in the signaling changes taking place during progression to CRPC. Immunohistochemistry (IHC) for MED15 on matched samples from the same patients before and after ADT reveals significantly increased MED15 expression after ADT in 72%. A validation cohort comprising samples before and after therapy confirmed our observations. Protein analysis for pAKT and pSMAD3 shows that MED15 correlates with PI3K and TGFß activities, respectively, and that hyper-activation of both pathways simultaneously correlates with highest levels of MED15. We further show that MED15 protein expression increases in LNCaP cells under androgen deprivation, and via EGF mediated PI3K activation. PI3K/mTOR and TGFß-receptor inhibition results in decreased MED15 expression. MED15 knockdown reduces LNCaP cell viability and induces apoptosis during androgen deprivation, while cell cycle is not affected. Collectively, MED15 overexpression arises during ADT via hyper-activation of PI3K/mTOR signaling, thus MED15 may serve as a predictive marker for response to PI3K/mTOR inhibitors. Furthermore, MED15 is potentially a therapeutic target for the treatment of CRPC.

Pan-Cancer Analysis of the Mediator Complex Transcriptome Identifies CDK19 and CDK8 as Therapeutic Targets in Advanced Prostate Cancer.

Purpose: The Mediator complex is a multiprotein assembly, which serves as a hub for diverse signaling pathways to regulate gene expression. Because gene expression is frequently altered in cancer, a systematic understanding of the Mediator complex in malignancies could foster the development of novel targeted therapeutic approaches.Experimental Design: We performed a systematic deconvolution of the Mediator subunit expression profiles across 23 cancer entities (n = 8,568) using data from The Cancer Genome Atlas (TCGA). Prostate cancer-specific findings were validated in two publicly available gene expression cohorts and a large cohort of primary and advanced prostate cancer (n = 622) stained by immunohistochemistry. The role of CDK19 and CDK8 was evaluated by siRNA-mediated gene knockdown and inhibitor treatment in prostate cancer cell lines with functional assays and gene expression analysis by RNAseq.Results: Cluster analysis of TCGA expression data segregated tumor entities, indicating tumor-type-specific Mediator complex compositions. Only prostate cancer was marked by high expression of CDK19 In primary prostate cancer, CDK19 was associated with increased aggressiveness and shorter disease-free survival. During cancer progression, highest levels of CDK19 and of its paralog CDK8 were present in metastases. In vitro, inhibition of CDK19 and CDK8 by knockdown or treatment with a selective CDK8/CDK19 inhibitor significantly decreased migration and invasion.Conclusions: Our analysis revealed distinct transcriptional expression profiles of the Mediator complex across cancer entities indicating differential modes of transcriptional regulation. Moreover, it identified CDK19 and CDK8 to be specifically overexpressed during prostate cancer progression, highlighting their potential as novel therapeutic targets in advanced prostate cancer. Clin Cancer Res; 23(7); 1829-40. ©2016 AACR.

Comprehensive analysis of the transcriptional profile of the Mediator complex across human cancer types.

The Mediator complex is a key regulator of gene transcription and several studies demonstrated altered expressions of particular subunits in diverse human diseases, especially cancer. However a systematic study deciphering the transcriptional expression of the Mediator across different cancer entities is still lacking.We therefore performed a comprehensive in silico cancer vs. benign analysis of the Mediator complex subunits (MEDs) for 20 tumor entities using Oncomine datasets. The transcriptional expression profiles across almost all cancer entities showed differentially expressed MEDs as compared to benign tissue. Differential expression of MED8 in renal cell carcinoma (RCC) and MED12 in lung cancer (LCa) were validated and further investigated by immunohistochemical staining on tissue microarrays containing large numbers of specimen. MED8 in clear cell RCC (ccRCC) associated with shorter survival and advanced TNM stage and showed higher expression in metastatic than primary tumors. In vitro, siRNA mediated MED8 knockdown significantly impaired proliferation and motility in ccRCC cell lines, hinting at a role for MED8 to serve as a novel therapeutic target in ccRCC. Taken together, our Mediator complex transcriptome proved to be a valid tool for identifying cancer-related shifts in Mediator complex composition, revealing that MEDs do exhibit cancer specific transcriptional expression profiles.

The long non-coding RNA lnc-ZNF180-2 is a prognostic biomarker in patients with clear cell renal cell carcinoma.

Clear cell renal cell carcinoma (ccRCC) is among the most common human malignancies. Long non-coding RNAs (lncRNA) regulate various cellular functions and have been implicated in ccRCC pathogenesis. In order to decipher the molecular biology of this tumor and to identify potential prognostic biomarkers and therapeutic targets, we re-evaluated published lncRNA expression profiling data. An expression profile of 49 lncRNAs allowed discrimination of localized and advanced ccRCC. The expression profile of six lncRNAs transcripts (lnc-ACO1625, lnc-CYP4A22-2/3, lnc-PEAK1.1-1, lnc-PCYOX1L, lnc-VCAN-1, lnc-ZNF180-2) with potential prognostic interest were validated in a cohort of 50 normal renal, 57 localized ccRCC and 45 advanced ccRCC tissues. lnc-ZNF180-2 levels were similar in localized ccRCC and normal renal tissue, but we observed a significant increase of lnc-ZNF180-2 expression in advanced ccRCC tissue. Furthermore, lnc-ZNF180-2 expression levels were an independent predictor of progression-free survival, cancer-specific survival and overall survival in ccRCC patients. We also observed that lnc-CYP4A22-2/3 expression levels allowed discrimination of ccRCC and normal renal tissue. In conclusion, lncRNAs are involved in renal carcinogenesis, and quantification of lnc-ZNF180-2 may be useful for the prediction of ccRCC patients outcome following nephrectomy.

NDUFA4 expression in clear cell renal cell carcinoma is predictive for cancer-specific survival.

Like other cancers, renal cell carcinoma (RCC) derives the essential energy for proliferation and survival from high rates of glycolysis rather than from oxidative phosphorylation of the mitochondrial respiration pathway. NDUFA4 (NADH Dehydrogenase (Ubiquinone) 1 Alpha Subcomplex, 4) is encoding a protein belonging to the respiratory chain of mitochondria. For a better understanding of the tumor biology and for identification of a potential new biomarker, we analyzed the regulation of NDUFA4 in RCC compared to normal tissue cells. Downregulation of NDUFA4 mRNA and protein was detected in RCC compared to normal renal tissues in quantitative real-time PCR as well as in western blot and immunohistochemical staining. Histological analysis revealed higher NDUFA4 expression in the distal tubules compared to the proximal tubules and the loop of Henle. A higher molecular weight of the NDUFA4 protein was discovered in RCC samples, possibly indicating a posttranslational modification. Moreover, NDUFA4 protein expression was predictive for cancer-specific survival. Our analysis revealed a potential new biomarker, but future studies are warranted to investigate the prognostic value of NDUF4A expression.

Identification of novel long non-coding RNAs in clear cell renal cell carcinoma.

BACKGROUND: Long non-coding RNAs (lncRNA) play an important role in carcinogenesis; knowledge on lncRNA expression in renal cell carcinoma is rudimental. As a basis for biomarker development, we aimed to explore the lncRNA expression profile in clear cell renal cell carcinoma (ccRCC) tissue. RESULTS: Microarray experiments were performed to determine the expression of 32,183 lncRNA transcripts belonging to 17,512 lncRNAs in 15 corresponding normal and malignant renal tissues. Validation was performed using quantitative real-time PCR in 55 ccRCC and 52 normal renal specimens. Computational analysis was performed to determine lncRNA-microRNA (MiRTarget2) and lncRNA-protein (catRAPID omics) interactions. We identified 1,308 dysregulated transcripts (expression change >2-fold; upregulated: 568, downregulated: 740) in ccRCC tissue. Among these, aberrant expression was validated using PCR: lnc-BMP2-2 (mean expression change: 37-fold), lnc-CPN2-1 (13-fold), lnc-FZD1-2 (9-fold), lnc-ITPR2-3 (15-fold), lnc-SLC30A4-1 (15-fold), and lnc-SPAM1-6 (10-fold) were highly overexpressed in ccRCC, whereas lnc-ACACA-1 (135-fold), lnc-FOXG1-2 (19-fold), lnc-LCP2-2 (2-fold), lnc-RP3-368B9 (19-fold), and lnc-TTC34-3 (314-fold) were downregulated. There was no correlation between lncRNA expression with clinical-pathological parameters. Computational analyses revealed that these lncRNAs are involved in RNA-protein networks related to splicing, binding, transport, localization, and processing of RNA. Small interfering RNA (siRNA)-mediated knockdown of lnc-BMP2-2 and lnc-CPN2-1 did not influence cell proliferation. CONCLUSIONS: We identified many novel lncRNA transcripts dysregulated in ccRCC which may be useful for novel diagnostic biomarkers.

Differential expression of Mediator complex subunit MED15 in testicular germ cell tumors.

BACKGROUND: Testicular germ cell tumors (TGCT) are the most common cancer entities in young men with increasing incidence observed in the last decades. For therapeutic management it is important, that TGCT are divided into several histological subtypes. MED15 is part of the multiprotein Mediator complex which presents an integrative hub for transcriptional regulation and is known to be deregulated in several malignancies, such as prostate cancer and bladder cancer role, whereas the role of the Mediator complex in TGCT has not been investigated so far. Aim of the study was to investigate the implication of MED15 in TGCT development and its stratification into histological subtypes. METHODS: Immunohistochemical staining (IHC) against Mediator complex subunit MED15 was conducted on a TGCT cohort containing tumor-free testis (n = 35), intratubular germ cell neoplasia unclassified (IGCNU, n = 14), seminomas (SEM, n = 107) and non-seminomatous germ cell tumors (NSGCT, n = 42), further subdivided into embryonic carcinomas (EC, n = 30), yolk sac tumors (YST, n = 5), chorionic carcinomas (CC, n = 5) and teratomas (TER, n = 2). Quantification of MED15 protein expression was performed through IHC followed by semi-quantitative image analysis using the Definiens software. RESULTS: In tumor-free seminiferous tubules, MED15 protein expression was absent or only low expressed in spermatogonia. Interestingly, the precursor lesions IGCNU exhibited heterogeneous but partly very strong MED15 expression. SEM weakly express the Mediator complex subunit MED15, whereas NSGCT and especially EC show significantly enhanced expression compared to tumor-free testis. CONCLUSIONS: In conclusion, MED15 is differentially expressed in tumor-free testis and TGCT. While MED15 is absent or low in tumor-free testis and SEM, NSGCT highly express MED15, hinting at the diagnostic potential of this marker to distinguish between SEM and NSGCT. Further, the precursor lesion IGCNU showed increased nuclear MED15 expression in the preinvasive precursor cells, which may provide diagnostic value to distinguish between benign and pre-malignant testicular specimen, and may indicate a role for MED15 in carcinogenesis in TGCT.

Prostaglandin receptors EP1-4 as a potential marker for clinical outcome in urothelial bladder cancer.

Prostaglandins, especially prostaglandin E2 (PGE2), and COX-2 play an important role in carcinogenesis of many tumors including bladder cancer (BCA). The PGE2 receptors EP1-4 regulate tumor cell growth, invasion and migration in different tumor entities but EP expression in BCA remains to be determined. In the present study we examined the expression of EP1-4 in non-muscle invasive bladder cancer (NMIBC), muscle invasive bladder cancer (MIBC) and normal urothelial tissue (NU) using immunohistochemistry. Nuclear and cytoplasmic EP1-4 expression was correlated with clinicopathological parameters and survival of BCA patients. EP1, EP2 and EP3 were significantly less expressed in the cytoplasm und nucleus of NMIBC and MIBC than in NU; EP4 cytoplasmic staining in MIBC was significantly higher compared to NU. The cytoplasmic staining was significantly more abundant in MIBC than in NMIBC in all investigated receptors except EP2. The level of EP staining in NMIBC was correlated with staging and grading, especially cytoplasmic EP1. Nuclear staining of EP1 was an independent predictor of BCA recurrence-free survival in NMIBC patients. EP receptors are dysregulated in BCA. The increase of EP1 may be used as prognostic parameter in NMIBC patients and its dysregulation could be targeted by specific EP1 inhibitors.

MED12 overexpression is a frequent event in castration-resistant prostate cancer.

In a recent effort to unravel the molecular basis of prostate cancer (PCa), Barbieri and colleagues using whole-exome sequencing identified a novel recurrently mutated gene, MED12, in 5.4% of primary PCa. MED12, encoding a subunit of the Mediator complex, is a transducer of Wnt/ß-catenin signaling, linked to modulation of hedgehog signaling and to the regulation of transforming growth factor beta (TGFß)-receptor signaling. Therefore, these studies prompted us to investigate the relevance of MED12 in PCa. Expression of MED12, SMAD3 phosphorylation, and proliferation markers was assessed by immunohistochemistry on tissue microarrays from 633 patients. siRNA-mediated knockdown of MED12 was carried out on PCa cell lines followed by cellular proliferation assays, cell cycle analysis, apoptosis assays, and treatments with recombinant TGFß3. We found nuclear overexpression of MED12 in 40% (28/70) of distant metastatic castration-resistant prostate cancer (CRPC(MET)) and 21% (19/90) of local-recurrent CRPC (CRPC(LOC)) in comparison with frequencies of less than 11% in androgen-sensitive PCa, and no overexpression in benign prostatic tissues. MED12 expression was significantly correlated with high proliferative activity in PCa tissues, whereas knockdown of MED12 decreased proliferation, reduced G1- to S-phase transition, and increased the expression of the cell cycle inhibitor p27. TGFß signaling activation associates with MED12 nuclear overexpression in tissues and results in a strong increase in MED12 nuclear expression in cell lines. Furthermore, MED12 knockdown reduced the expression of the TGFß target gene vimentin. Our findings show that MED12 nuclear overexpression is a frequent event in CRPC in comparison with androgen-sensitive PCa and is directly implicated in TGFß signaling.