The effect of grainyhead‐like transcription factor 3 (GRHL3) on cancer development depends on the cancer subtypes as shown in tumor entities such as colorectal or oral squamous cell carcinomas. Here, ...we analyzed the subtype‐specific role of GRHL3 in bladder carcinogenesis, comparing common urothelial carcinoma (UC) with squamous bladder cancer (sq‐BLCA). We examined GRHL3 mRNA and protein expression in cohorts of patient samples, its prognostic role and its functional impact on tumorigeneses in different molecular and histopathological subtypes of bladder cancer. We showed for GRHL3 a reverse expression in squamous and urothelial bladder cancer subtypes. Stably GRHL3‐overexpressing EJ28, J82, and SCaBER in vitro models revealed a tumor‐suppressive function in squamous and an oncogenic role in the urothelial cancer cells affecting cell and colony growth, and migratory and invasive capacities. Transcriptomic profiling demonstrated highly subtype‐specific GRHL3‐regulated expression networks coined by the enrichment of genes involved in integrin‐mediated pathways. In SCaBER, loss of ras homolog family member A (RHOA) GTPase activity was demonstrated to be associated with co‐regulation of eukaryotic translation initiation factor 4E family member 3 (EIF4E3), a potential tumor suppressor gene. Thus, our data provide for the first time a detailed insight into the role of the transcription factor GRHL3 in different histopathological subtypes of bladder cancer.
In the urinary bladder, GRHL3 function in cancer development depends on the histological subtype and molecular background. In urothelial carcinomas (UC), GRHL3 is strongly expressed, whereas it is downregulated in squamous cell carcinomas (SCC). In vitro opposite functions were confirmed in GRHL3‐overexpressing models for SCC and UC affecting cell growth, migration, invasion, focal adhesion, and GTPase activity in a subtype‐specific manner.
Dickkopf 3 (DKK3) has been associated with tumor suppression of various tumor entities including breast cancer. However, the functional impact of DKK3 on the tumorigenesis of distinct molecular ...breast cancer subtypes has not been considered so far. Therefore, we initiated a study analyzing the subtype-specific DKK3 expression pattern as well as its prognostic and functional impact with respect to breast cancer subtypes. Based on three independent tissue cohorts including one in silico dataset (n = 30, n = 463 and n = 791) we observed a clear down-regulation of DKK3 expression in breast cancer samples compared to healthy breast tissue controls on mRNA and protein level. Interestingly, most abundant reduction of DKK3 expression was detected in the highly aggressive basal breast cancer subtype. Analyzing a large in silico dataset comprising 3,554 cases showed that low DKK3 mRNA expression was significantly associated with reduced recurrence free survival (RFS) of luminal and basal-like breast cancer cases. Functionally, DKK3 re-expression in human breast cancer cell lines led to suppression of cell growth possibly mediated by up-regulation of apoptosis in basal-like but not in luminal-like breast cancer cell lines. Moreover, ectopic DKK3 expression in mesenchymal basal breast cancer cells resulted in partial restoration of epithelial cell morphology which was molecularly supported by higher expression of epithelial markers like E-Cadherin and down-regulation of mesenchymal markers such as Snail 1. Hence, we provide evidence that down-regulation of DKK3 especially promotes tumorigenesis of the aggressive basal breast cancer subtype. Further studies decoding the underlying molecular mechanisms of DKK3-mediated effects may help to identify novel targeted therapies for this clinically highly relevant breast cancer subtype.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
NDRG2, a member of the N-myc downstream-regulated gene family, is thought to be a putative tumor suppressor gene with promising clinical impact in breast cancer. Since breast cancer comprises ...heterogeneous intrinsic subtypes with distinct clinical outcomes we investigated the pivotal role of NDRG2 in basal-type breast cancers. Based on subtype classified tumor (n = 45) and adjacent normal tissues (n = 17) we examined NDRG2 mRNA expression and CpG-hypermethylation, whose significance was further validated by independent data sets from The Cancer Genome Atlas (TCGA). In addition, NDRG2 protein expression was evaluated immunohistochemically using a tissue micro array (TMA, n = 211). In vitro, we investigated phenotypic effects caused by NDRG2 silencing in the basal A-like HCC1806 as well as NDRG2 over-expression in basal A-like BT20 compared to luminal-type MCF7 breast cancer cells. Our tissue collections demonstrated an overall low NDRG2 mRNA expression in breast cancer subtypes compared to normal breast tissue in line with an increased CpG-hypermethylation in breast cancer tissue. Independent TCGA data sets verified a significant (P<0.001) expression loss of NDRG2 in breast tumors. Of interest, basal-like tumors more frequently retained abundant NDRG2 expression concordant with a lower CpG-hypermethylation. Unexpectedly, basal-like breast cancer revealed an association of NDRG2 expression with unfavorable patients' outcome. In line with this observation, in vitro experiments demonstrated reduced proliferation and migration rates (~20%) in HCC1806 cells following NDRG2 silencing. In contrast, NDRG2 over-expressing luminal-type MCF7 cells demonstrated a 26% decreased proliferation rate. Until now, this is the first study investigating the putative role of NDRG2 in depth in basal-type breast cancer. Our data indicate that the described putative tumor suppressive function of NDRG2 may be confined to luminal- and basal B-type breast cancers.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Posttranslational protein modifications are known to modulate key biological processes like proliferation and apoptosis. Accumulating evidence shows that ST6GAL1, an enzyme that catalyzes the ...transfer of sialic acid onto galactose-containing substrates, is aberrantly expressed in various cancers and may affect cell motility and invasion. This is the first study to describe ST6GAL1 expression and regulation in human bladder cancer.
ST6GAL1 mRNA expression levels in human cell lines (UROtsa, RT4, RT112 and J82) and tissue samples (n = 15 normal urothelium (NU), n = 13 papillary non-invasive tumors (pTa), n = 12 carcinoma in situ (CIS), n = 26 muscle invasive tumors (pT2-4)) were assessed using real-time PCR. In addition, ST6GAL1 protein expression was evaluated using immunohistochemistry. Promoter methylation analysis was performed using methylation-specific PCR (MSP) in cell lines (n = 4) and patient samples (n = 23 NU, n = 12 CIS, n = 29 pTa, n = 41 pT2-4). Epigenetic ST6GAL1 gene silencing was confirmed by in vitro demethylation of bladder cell lines. Data were validated by analysis of an independent bladder tumor data set (n = 184) based on The Cancer Genome Atlas (TCGA) portal.
Semi-quantitative ST6GAL1 real-time PCR expression analysis showed two distinct trends: In muscle-invasive tumors ST6GAL1 expression was downregulation by 2.7-fold, while papillary non-invasive tumors showed an increased ST6GAL1 mRNA expression compared to normal urothelium. ST6GAL1 loss in muscle-invasive tumors was associated with increasing invasiveness. On the protein level, 69.2% (n = 45/65) of all tumors showed a weak ST6GAL1 protein staining (IRS ≤ 4) while 25.6% (16/65) exhibited a complete loss (IRS = 0) of ST6GAL1 protein. Tumor-specific DNA methylation of the ST6GAL1 promoter region was frequently found in pT2-4 tumors (53.6% (22/41)), whereas only 13.8% (4/29) of pTa tumors showed ST6GAL1 promoter methylation. Normal urothelium remained unmethylated. Importantly, we significantly revealed an inverse correlation between ST6GAL1 mRNA expression and ST6GAL1 promoter merthylation in primary bladder cancer. These findings were clearly verified by the TCGA public data set and in vitro demethylation assays functionally confirmed ST6GAL1 promoter methylation as a potential regulatory factor for ST6GAL1 gene silencing.
Our study characterizes for the first time ST6GAL1 expression loss caused by aberrant ST6GAL1 promoter methylation potentially indicating a tumor suppressive role in bladder carcinogenesis.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Summary
Virus detection methods are important to cope with the SARS‐CoV‐2 pandemics. Apart from the lung, SARS‐CoV‐2 was detected in multiple organs in severe cases. Less is known on organ tropism in ...patients developing mild or no symptoms, and some of such patients might be missed in symptom‐indicated swab testing. Here, we tested and validated several approaches and selected the most reliable RT‐PCR protocol for the detection of SARS‐CoV‐2 RNA in patients’ routine diagnostic formalin‐fixed and paraffin‐embedded (FFPE) specimens available in pathology, to assess (i) organ tropism in samples from COVID‐19‐positive patients, (ii) unrecognized cases in selected tissues from negative or not‐tested patients during a pandemic peak, and (iii) retrospectively, pre‐pandemic lung samples. We identified SARS‐CoV‐2 RNA in seven samples from confirmed COVID‐19 patients, in two gastric biopsies, one small bowel and one colon resection, one lung biopsy, one pleural resection and one pleural effusion specimen, while all other specimens were negative. In the pandemic peak cohort, we identified one previously unrecognized COVID‐19 case in tonsillectomy samples. All pre‐pandemic lung samples were negative. In conclusion, SARS‐CoV‐2 RNA detection in FFPE pathology specimens can potentially improve surveillance of COVID‐19, allow retrospective studies, and advance our understanding of SARS‐CoV‐2 organ tropism and effects.
We tested and validated methods for detection of SARS‐CoV‐2 RNA in human formalin‐fixed, paraffin‐embedded specimens used in diagnostic pathology. We have then used the most reliable method to assess various application fields, showing its potential in retrospective studies, as an alternative surveillance approach and to advance our understanding of SARS‐CoV‐2 organ tropism and effects.
Bladder cancer is one of the more common malignancies in humans and the most expensive tumor for treating in the Unites States (US) and Europe due to the need for lifelong surveillance. Non-invasive ...tests approved by the FDA have not been widely adopted in routine diagnosis so far. Therefore, we aimed to characterize the two putative tumor suppressor genes
and
as novel urinary DNA methylation biomarkers that are suitable for non-invasive detection of bladder cancer. While assessing the analytical performance, a spiking experiment was performed by determining the limit of RT112 tumor cell detection (range: 100-10,000 cells) in the urine of healthy donors in dependency of the processing protocols of the RWTH cBMB. Clinically, urine sediments of 474 patients were analyzed by using quantitative methylation-specific PCR (qMSP) and Methylation Sensitive Restriction Enzyme (MSRE) qPCR techniques. Overall,
-
showed a sensitivity of 64% to 70% with a specificity ranging between 80% and 92%, i.e., discriminating healthy, benign lesions, and/or inflammatory diseases from bladder tumors. When comparing single biomarkers,
achieved a sensitivity of 73%, which was increased by combination with the known biomarker candidate
up to 76% at a specificity of 97%. Hence,
and, in particular,
might be promising candidates for further optimizing current bladder cancer biomarker panels and platforms.
Summary Postmortem computed tomography (PMCT) is a modern tool that complements autopsy diagnostics. In clinical autopsies, a major cause of death is cardiovascular disease. To improve the ...performance of PMCT in cardiovascular disease, full body angiography was developed (PMCT angiography PMCTA). Twenty PMCTA scans generated before autopsy were compared with native PMCT and clinical autopsy. The objective of the study was to quantify the additional diagnostic value of adding angiography to native imaging and to compare PMCT and PMCTA findings to autopsy findings. The diagnosis of the cause of death was identical or overlapped in 80% of the cases that used PMCTA and 70% that used PMCT. The additional diagnostic yield given by PMCT and PMCTA in combination with autopsy was 55%. PMCT yielded additional diagnoses in the musculoskeletal system. The greatest additional diagnostic value of PMCTA was in association with cardiovascular diagnoses. The accuracy of PMCTA for cardiac causes of death was 80%, and the positive predictive value was 90%. The findings indicate that native PMCT cannot display the cardiovascular system sufficiently clearly for high-quality diagnostic assessment. However, PMCTA is a powerful tool in autopsy cases with a history of cardiovascular disease and/or a suspected cardiovascular cause of death. The combination of PMCTA and clinical autopsy enhances diagnostic quality and completeness of the autopsy report. Furthermore, in cases without consent or with a restricted consent for clinical autopsy, PMCTA has the potential to provide information on cardiovascular causes of death.
To evaluate the diagnostic value of contrast enhanced post mortem computed tomography (PMCT) in comparison to non-enhanced post mortem CT in the detection of cardiovascular causes of death (COD).
As ...autopsy rates decline, new methods to determine CODs are necessary. So contrast enhanced PMCT shall be evaluated in comparison to established non-enhanced PMCT in order to further improve the method.
In a prospective study, 20 corpses were examined using a 64-row multisclice CT (MSCT) before and after intraarterial perfusion with a newly developed, barium-bearing contrast agent and ventilation of the lungs. The cause of death was determined in enhanced and unenhanced scans and a level of confidence (LOC) was given by three experienced radiologists on a scale between 0 and 4. Results were compared to autopsy results as gold standard. Autopsy was performed blinded to PMCT-findings.
The method allowed visualization of different types of cause of death. There was a significant improvement in LOC in enhanced scans compared to unenhanced scans as well as an improvement in the detection of COD. The cause of death could be determined in 19 out of 20 patients.
PMCT is feasible and appears to be robust for diagnosing cardiovascular causes of death. When compared with unenhanced post-mortem CT intraarterial perfusion and pulmonary ventilation significantly improve visualization and diagnostic accuracy. These promising results warrant further studies.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Genome-wide studies identified pan-cancer genes and shared biological networks affected by epigenetic dysregulation among diverse tumor entities. Here, we systematically screened for hypermethylation ...of DNA damage repair (DDR) genes in a comprehensive candidate-approach and exemplarily identify and validate candidate DDR genes as targets of epigenetic inactivation unique to bladder cancer (BLCA), which may serve as non-invasive biomarkers.
Genome-wide DNA methylation datasets (2755 CpG probes of
= 7819 tumor and
= 659 normal samples) of the TCGA network covering 32 tumor entities were analyzed in silico for 177 DDR genes. Genes of interest were defined as differentially methylated between normal and cancerous tissues proximal to transcription start sites. The lead candidate gene was validated by methylation-specific PCR (MSP) and/or bisulfite-pyrosequencing in different human cell lines (
= 36), in primary BLCA tissues (
= 43), and in voided urine samples (
= 74) of BLCA patients. Urines from healthy donors and patients with urological benign and malignant diseases were included as controls (
= 78). mRNA expression was determined using qRT-PCR in vitro before (
= 5) and after decitabine treatment (
= 2). Protein expression was assessed by immunohistochemistry (
= 42). R 3.2.0. was used for statistical data acquisition and SPSS 21.0 for statistical analysis.
Overall, 39 DDR genes were hypermethylated in human cancers. Most exclusively and frequently methylated (37%) in primary BLCA was
, encoding endonuclease CtIP.
hypermethylation predicted longer overall survival (OS) and was found in 2/4 bladder cancer cell lines but not in any of 33 cancer cell lines from entities with another origin like prostate.
methylation was inversely correlated with RBBP8 mRNA and nuclear protein expression while RBBP8 was re-expressed after in vitro demethylation.
methylation was associated with histological grade in primary BLCA and urine samples.
methylation was detectable in urine samples of bladder cancer patients achieving a sensitivity of 52%, at 91% specificity.
was identified as almost exclusively hypermethylated in BLCA.
/CtIP has a proven role in homologous recombination-mediated DNA double-strand break repair known to sensitize cancer cells for PARP1 inhibitors. Since
methylation was detectable in urines, it may be a complementary marker of high specificity in urine for BLCA detection.