Inhibition of Cyclin-Dependent Kinase 8/Cyclin-Dependent Kinase 19 Suppresses Its Pro-Oncogenic Effects in Prostate Cancer.

Progression of prostate cancer (PCa) is characterized by metastasis and castration resistance after response to androgen deprivation. Therapeutic options are limited, causing high morbidity and lethality. Recent work reported pro-oncogenic implications of the Mediator subunits cyclin-dependent kinase (CDK) 8 and 19 for the progression of PCa. The current study explored the underlying molecular mechanisms of CDK8/CDK19 and tested effects of novel CDK8/CDK19 inhibitors. PC3, DU145, LNCaP, and androgen-independent LNCaP Abl were used for in vitro experiments. Two inhibitors and CDK19 overexpression were used to modify CDK8/CDK19 activity. MTT assay, propidium iodide staining, wound healing assay, Boyden chamber assay, and adhesion assay were used to investigate cell viability, cell cycle, migration, and adhesion, respectively. Peptide-kinase screen using the PamGene platform was conducted to identify phosphorylated targets. Combining CDK8/CDK19 inhibitors with anti-androgens led to synergistic antiproliferative effects and sensitized androgen-independent cells to bicalutamide. CDK8/CDK19 inhibition resulted in reduced migration and increased collagen I-dependent adhesion. Phosphorylation of multiple peptides linked to cancer progression was identified to be dependent on CDK8/CDK19. In summary, this study substantially supports recent findings on CDK8/CDK19 in PCa progression. These findings contribute to a better understanding of underlying pro-oncogenic effects, which is needed to develop CDK8/CDK19 as a therapeutic target in PCa.

TRIM21 Expression as a Prognostic Biomarker for Progression-Free Survival in HNSCC.

Patients with head and neck squamous cell carcinoma (HNSCC) continue to have a rather poor prognosis. Treatment-related comorbidities have negative impacts on their quality of life. TRIM21 is a cytosolic E3 ubiquitin ligase that was initially described as an autoantigen in autoimmune diseases and later associated with the intracellular antiviral response. Here, we investigated the role of TRIM21 as a biomarker candidate for HNSCC in predicting tumor progression and patient survival. We analyzed TRIM21 expression and its association with clinical-pathological parameters in our HNSCC cohort using immunohistochemistry. Our HNSCC cohort included samples from 419 patients consisting of primary tumors (n = 337), lymph node metastases (n = 156), recurrent tumors (n = 54) and distant metastases (n = 16). We found that cytoplasmic TRIM21 expression was associated with the infiltration of immune cells into primary tumors. In addition, TRIM21 expression was significantly higher in primary tumors than in lymph node metastases, and increased TRIM21 expression was correlated with shorter progression-free survival in HNSCC patients. These results suggest that TRIM21 could be a new biomarker for progression-free survival.

Targeting cyclin-dependent kinase 7-association between CDK7 and pMED1 expression in prostate cancer tissue.

Cyclin-dependent kinase (CDK) 7-mediated phosphorylation of Mediator-complex subunit 1 (MED1) enhances androgen receptor (AR) activity in prostate cancer (PCa). Hyperactive AR-signalling plays a key role for the development of castration resistance. Several CDK7 inhibitors are currently under investigation in Phase I/II trials addressing solid tumours, including PCa. Aim of this study was to characterize the CDK7/phospho-(p)MED1 axis in human tissue. Immunohistochemistry was performed on 595 PCa samples including 394 primary tumour foci obtained by radical prostatectomy (RP), 64 advanced or recurrent tumours obtained by palliative transurethral resection of the prostate (pTUR), 65 lymph node metastases (LNM), 35 distant metastases (DM) and 36 benign samples. CDK7 is expressed in 79.3% of PCa tissues and protein levels are significantly higher in LNM, pTUR and DM and lower in benign tissues compared to primary tumours. CDK7 and pMED1 expression show strong positive correlation. High expression of CDK7 associated with shorter 5-year biochemical recurrence-free-survival (63.0% vs. 85.0%) and reduced survival persists when adjusted for T-Stage, nodal status, resection boundaries, grade group and pre-operative prostate-specific antigen in multivariate Cox-regression (hazard ratio 4.30; 95% CI, 1.43 to 12,40, P = 0.007). High CDK7 and pMED1 levels correlate with nuclear AR expression. CDK7 positive tumours harbour higher Ki67 expression indices and show more frequently positive ERG (ETS-related gene)-status. In conclusion, CDK7 is frequently expressed in human PCa and predicts disease recurrence after RP. Therapeutical inhibition of CDK7 might be a promising approach in treatment of advanced PCa.

The Gene Expression Landscape of Prostate Cancer BM Reveals Close Interaction with the Bone Microenvironment.

Bone metastatic (BM) prostate cancer (PCa) belongs to the most lethal form of PCa, and therapeutic options are limited. Molecular profiling of metastases contributes to the understanding of mechanisms defining the bone metastatic niche. Our aim was to explore the transcriptional profile of PCa BM and to identify genes that drive progression. Paraffin-embedded tissues of 28 primary PCa and 30 BM were submitted to RNA extraction and analyzed by RNA sequencing using the Nanostring nCounter gene expression platform. A total of 770 cancer-related genes were measured using the Nanostring™ PanCancer progression panel. Gene Ontology (GO), KEGG, Reactome, STRING, Metascape, PANTHER, and Pubmed were used for data integration and gene annotation. We identified 116 differentially expressed genes (DEG) in BM compared to primaries. The most significant DEGs include CD36, FOXC2, CHAD, SPP1, MMPs, IBSP, and PTX3, which are more highly expressed in BM, and ACTG2, MYH11, CNN1, FGF2, SPOCK3, and CHRDL1, which have a lower expression. DEGs functionally relate to extracellular matrix (ECM) proteoglycans, ECM-receptors, cell-substrate adhesion, cell motility as well as receptor tyrosine kinase signaling and response to growth factors. Data integration and gene annotation of 116 DEGs were used to build a gene platform which we termed "Manually Annotated and Curated Nanostring-data Platform". In summary, our results highlight the significance of certain genes in PCa BM to which essential pro-metastatic functions could be ascribed. Data from this study provide a comprehensive platform of genes that are related to PCa BM and provide evidence for further investigations.

Analysis of tripartite motif (TRIM) family gene expression in prostate cancer bone metastases.

Tripartite motif (TRIM) family proteins are post-translational protein modifiers with E3-ubiquitin ligase activity, thereby involved in various biological processes. The molecular mechanisms driving prostate cancer (PCa) bone metastasis (BM) are incompletely understood, and targetable genetic alterations are lacking in the majority of cases. Therefore, we aimed to explore the expression and potential functional relevance of 71 TRIM members in bone metastatic PCa. We performed transcriptome analysis of all human TRIM family members and 770 cancer-related genes in 29 localized PCa and 30 PCa BM using Nanostring. KEGG, STRING and Ubibrowser were used for further bioinformatic gene correlation and pathway enrichment analyses. Compared to localized tumors, six TRIMs are under-expressed while nine TRIMs are over-expressed in BM. The differentially expressed TRIM proteins are linked to TNF-, TGFß-, PI3K/AKT- and HIF-1-signaling, and to features such as proteoglycans, platelet activation, adhesion and ECM-interaction based on correlation to cancer-related genes. The identification of TRIM-specific E3-ligase-substrates revealed insight into functional connections to oncogenes, tumor suppressors and cancer-related pathways including androgen receptor- and TGFß signaling, cell cycle regulation and splicing. In summary, this is the first study that comprehensively and systematically characterizes the expression of all TRIM members in PCa BM. Our results describe post-translational protein modification as an important regulatory mechanism of oncogenes, tumor suppressors, and pathway molecules in PCa progression. Therefore, this study may provide evidence for novel therapeutic targets, in particular for the treatment or prevention of BM.

Increased mediator complex subunit CDK19 expression associates with aggressive prostate cancer.

The Mediator complex is a transcriptional regulator interacting with transcription factors and RNA-polymerase-II. Recently, we identified its subunit CDK19 to be specifically expressed in prostate cancer (PCa) and to be functionally implicated in PCa aggressiveness. Aim of our study was to comprehensively characterize the protein expression of CDK19 and its paralog CDK8 in PCa. We performed immunohistochemistry (IHC) for CDK19/CDK8 on a large cohort including needle biopsies from 202 patients, 799 primary tumor foci of radical prostatectomy specimens from 415 patients, 120 locally advanced tumor foci obtained by palliative transurethral resection, 140 lymph node metastases, 67 distant metastases and 82 benigns. Primary tumors were stained for the proliferation marker Ki67, androgen receptor (AR) and ERG. For 376 patients, clinic-pathologic data were available. Primary endpoint was disease-recurrence-free survival (DFS). Nuclear CDK19 and CDK8 expression increases during progression showing the highest intensity in metastatic and castration-resistant tumors. High CDK19 expression on primary tumors correlates with DFS independently from Gleason grade and PSA. Five-year-DFS rates of patients with primary tumors expressing no, moderate and high CDK19 are 73.7, 56.9 and 30.4%, respectively. CDK19 correlates with Gleason grade, T-stage, Ki67 proliferation-index, nuclear AR expression and ERG-status. Therapeutic options for metastatic and castration-resistant PCa remain limited. In the current study, we confirmed an important role of the Mediator subunit CDK19 in advanced PCa supporting current developments to target CDK19 and its paralog CDK8. Furthermore, CDK19 protein expression has the potential to predict disease recurrence independently from established biomarkers thus contributing to individual management for PCa patients.

Co-staining of microRNAs and their target proteins by miRNA in situ hybridization and immunohistofluorescence on prostate cancer tissue microarrays.

The co-expression of miRNAs and their target proteins was studied on tissue microarrays from different prostate cancer (PCa) patients. PCa of primary Gleason pattern 4 (GP4), lymph node metastases of GP4, distant metastases, and normal tissue from the transitional and peripheral zones were co-stained by fluorescent miRNA in situ hybridization (miRisH) and protein immunohistofluorescence (IHF). The miRNAs and corresponding target proteins include the pairs miR-145/ERG, miR-143/uPAR, and miR-375/SEC23A. The fluorescence-stained and scanned tissue microarrays (TMAs) were evaluated by experienced uropathologists. The pair miR-145/ERG showed an exclusive staining for miR-145 in the nuclei of stromal cells, both in tumor and normal tissue, and for ERG in the cytoplasm with/without co-expression in the nucleus of tumor cells. The pair miR-143/uPAR revealed a clear distinction between miR-143 in the nuclei of stromal cells and uPAR staining in the cytoplasm of tumor cells. Metastases (lymph node and distant) however, showed tumor cells with cytoplasmic staining for miR-143/uPAR. In normal tissues, beside the nuclei of the stroma cells, gland cells could also express miR-143 and uPAR in the cytoplasm. miR-375 showed particular staining in the nucleoli of GP4 and metastatic samples, suggesting that nucleoli play a special role in sequestering proteins and miRNAs. Combined miRisH/IHF allows for the study of miRNA expression patterns and their target proteins at the single-cell level.

Bone biopsy protocol for advanced prostate cancer in the era of precision medicine.

BACKGROUND: Metastatic biopsies are increasingly being performed in patients with advanced prostate cancer to search for actionable targets and/or to identify emerging resistance mechanisms. Due to a predominance of bone metastases and their sclerotic nature, obtaining sufficient tissue for clinical and genomic studies is challenging. METHODS: Patients with prostate cancer bone metastases were enrolled between February 2013 and March 2017 on an institutional review board-approved protocol for prospective image-guided bone biopsy. Bone biopsies and blood clots were collected fresh. Compact bone was subjected to formalin with a decalcifying agent for diagnosis; bone marrow and blood clots were frozen in optimum cutting temperature formulation for next-generation sequencing. Frozen slides were cut from optimum cutting temperature cryomolds and evaluated for tumor histology and purity. Tissue was macrodissected for DNA and RNA extraction, and whole-exome sequencing and RNA sequencing were performed. RESULTS: Seventy bone biopsies from 64 patients were performed. Diagnostic material confirming prostate cancer was successful in 60 of 70 cases (85.7%). The median DNA/RNA yield was 25.5 ng/µL and 16.2 ng/µL, respectively. Whole-exome sequencing was performed successfully in 49 of 60 cases (81.7%), with additional RNA sequencing performed in 20 of 60 cases (33.3%). Recurrent alterations were as expected, including those involving the AR, PTEN, TP53, BRCA2, and SPOP genes. CONCLUSIONS: This prostate cancer bone biopsy protocol ensures a valuable source for high-quality DNA and RNA for tumor sequencing and may be used to detect actionable alterations and resistance mechanisms in patients with bone metastases. Cancer 2018;124:1008-15. © 2017 American Cancer Society.

Primary Urethral Plasmacytoma Treated with High-Dose-Rate Brachytherapy: A Case Report.

Primary urethral solitary plasmacytoma is a very rare variant of extramedullary plasmacytoma. In total, only 9 cases have been reported so far. Patients were treated either by surgery or by external radiation therapy. Here, we report on a 22-year-old man, initially presenting with a palpable induration at the penis, intermittent dysuria and haematospermia, which was due to histologically confirmed solitary urethral kappa-restricted plasmacytoma. The patient subsequently underwent percutaneous and endo-urethral high-dose-rate brachytherapy with a total dose of 42 Gy applied in 14 fractions. Besides an uncomplicated urinary tract infection and hyperpigmentation of the penis, the patient tolerated the radiotherapy well and is still free of disease after 15 months follow-up.

The Epidermal Growth Factor Receptor (EGFR) Inhibitor Gefitinib Reduces but Does Not Prevent Tumorigenesis in Chemical and Hormonal Induced Hepatocarcinogenesis Rat Models.

Activation of the epidermal growth factor receptor (EGFR) signaling pathway promotes the development of hepatocellular adenoma (HCA) and carcinoma (HCC). The selective EGFR inhibitor Gefitinib was found to prevent hepatocarcinogenesis in rat cirrhotic livers. Thus, Gefitinib might reduce progression of pre-neoplastic liver lesions to HCC. In short- and long-term experiments, administration of N-Nitrosomorpholine (NNM) or intrahepatic transplantation of pancreatic islets in diabetic (PTx), thyroid follicles in thyroidectomized (TTx) and ovarian fragments in ovariectomized (OTx) rats was conducted for the induction of foci of altered hepatocytes (FAH). Gefitinib was administered for two weeks (20 mg/kg) or three and nine months (10 mg/kg). In NNM-treated rats, Gefitinib administration decreased the amount of FAH when compared to controls. The amount of HCA and HCC was decreased, but development was not prevented. Upon all transplantation models, proliferative activity of FAH was lower after administration of Gefitinib in short-term experiments. Nevertheless, the burden of HCA and HCC was not changed in later stages. Thus, EGFR inhibition by Gefitinib diminishes chemical and hormonal also induced hepatocarcinogenesis in the initiation stage in the non-cirrhotic liver. However, progression to malignant hepatocellular tumors was not prevented, indicating only a limited relevance of the EGFR signaling cascade in later stages of hepatocarcinogenesis.

CEACAM6 Promotes Lung Metastasis via Enhancing Proliferation, Migration and Suppressing Apoptosis of Prostate Cancer Cells.

BACKGROUND/AIM: Metastatic prostate cancer (mPCa) results in high morbidity and mortality. Visceral metastases in particular are associated with a shortened survival. Our aim was to unravel the molecular mechanisms that underly pulmonary spread in mPCa. MATERIALS AND METHODS: We performed a comprehensive transcriptomic analysis of PCa lung metastases, followed by functional validation of candidate genes. Digital gene expression analysis utilizing the NanoString technology was performed on mRNA extracted from formalin-fixed, paraffin-embedded (FFPE) tissue from PCa lung metastases. The gene expression data from primary PCa and PCa lung metastases were compared, and several publicly available bioinformatic analysis tools were used to annotate and validate the data. RESULTS: In PCa lung metastases, 234 genes were considerably up-regulated, and 78 genes were significantly down-regulated when compared to primary PCa. Carcinoembryonic antigen-related cell adhesion molecule 6 (CEACAM6) was identified as suitable candidate gene for further functional validation. CEACAM6 as a cell adhesion molecule has been implicated in promoting metastatic disease in several solid tumors, such as colorectal or gastric cancer. We showed that siRNA knockdown of CEACAM6 in PC-3 and LNCaP cells resulted in decreased cell viability and migration as well as enhanced apoptosis. Comprehensive transcriptomic analyses identified several genes of interest that might promote metastatic spread to the lung. CONCLUSION: Functional validation revealed that CEACAM6 might play an important role in fostering metastatic spread to the lung of PCa patients via enhancing proliferation, migration and suppressing apoptosis in PC-3 and LNCaP cells. CEACAM6 might pose an attractive therapeutic target to prevent metastatic disease.

Molecular and metabolic changes in human liver clear cell foci resemble the alterations occurring in rat hepatocarcinogenesis.

BACKGROUND & AIMS: Activation of the AKT/mTOR and Ras/MAPK pathways and the lipogenic phenotype occurs in both a rat model of insulin-induced hepatocarcinogenesis and in human hepatocellular carcinoma (HCC). In the rat model, activation of these pathways is evident within the earliest morphologic detectable alterations, i.e., clear cell foci (CCF) of altered hepatocytes. CCF have also been described in the human liver, but molecular and metabolic alterations within these foci remain to be determined. METHODS: A collection of human liver specimens was examined using electron microscopy, histology, enzyme- and immunohistochemistry, and molecular analysis. Human data were compared to rat preneoplastic CCF and HCC induced by N-nitrosomorpholine administration. RESULTS: CCF occurred in ∼33% of extrafocal tissues of human non-cirrhotic livers. Electron microscopy showed massive glycogen storage within CCF, largely due to the reduced activity of the glycogenolytic enzyme glucose-6-phosphatase. Hepatocytes in CCF overexpressed the insulin receptor and glucose transporter proteins. AKT/mTOR and Ras/MAPK pathways as well as enzymes of glycolysis, de novo lipogenesis, beta-oxidation, and cholesterol synthesis were upregulated, both in human CCF, and in CCF and HCC of N-nitrosomorpholine-treated rats. The Ki-67 proliferation index was 2-fold higher in human CCF than in extrafocal tissue. CONCLUSIONS: The high degree of similarity between human CCF and pre-neoplastic lesions from experimental models of hepatocarcinogenesis in terms of morphologic, molecular and metabolic features suggests a low-grade dysplastic nature of these lesions in human non-cirrhotic livers.

Comparison of p40 (ΔNp63) and p63 expression in prostate tissues--which one is the superior diagnostic marker for basal cells?

AIMS: p63 is one of the standard markers for basal cells of the prostate gland. Recently, it has been suggested that the p63 isoform p40 might be more specific as a basal cell marker. In this study we compare the staining characteristics of p63 and p40 in normal and malignant prostate tissues. METHODS AND RESULTS: A prostatectomy cohort (n = 640) in tissue microarray format was evaluated for p63 (clone 4A4) and for p40 (rabbit polyclonal) immunoreactivity in malignant and normal tissues. Immunoreactivity of basal and secretory cells was evaluated in a semiquantitative manner and compared case-wise. In normal tissues, p40 showed highly similar immunoreactivity compared to p63. The staining patterns were absolutely identical in 88% of cases. Additional cytoplasmic p40 staining in tumour cells occurred in 59.6% of cancer cases. Differences were seen in nuclear staining of carcinomas: 1.4% of carcinomas were p63-positive, whereas 0.6% were p40-positive. CONCLUSIONS: In most cases, p40 stains prostatic basal cells as reliably as p63, with only minor differences. Aberrant staining of tumour cells is seen more rarely than with p63 (clone 4A4), establishing its higher specificity. However, additional cytoplasmic immunoreactivity narrows its eligibility for antibody cocktails (e.g. with alpha-methylacyl-CoA racemase).

Elevated PSPC1 and KDM5C expression indicates poor prognosis in prostate cancer.

Prostate cancer (PCa) remains the most commonly diagnosed cancer in men worldwide and is still the second leading cause of cancer-related death. One major cause of PCa development is epigenetic aberration, including histone modification. We have previously demonstrated that Lysine Demethylase 5C (KDM5C) plays an essential role in the development of PCa and drives PCa progression by promoting epithelial-mesenchymal transition. Epigenetic regulators often work in concert, for example, to regulate transcription. We identified Paraspeckle Component 1 (PSPC1) as an interacting protein of KDM5C, suggesting that these proteins might function together in PCa. Here, we systematically investigate the expression patterns of KDM5C and PSPC1 in 2 independent prostate cohorts (432 and 205 prostate tumors in total for PSPC1 and KDM5C, respectively) by immunohistochemistry. We demonstrate that the expression of PSPC1 correlates with that of KDM5C. In addition, PSPC1 is up-regulated in primary and metastatic PCa. Elevated PSPC1 expression correlates with a higher-grade group and an advanced T-stage. Patients with high PSPC1 expression have a worse biochemical recurrence-free survival. In addition, PSPC1 expression is an independent prognostic parameter. Our data indicate that KDM5C and PSPC1 are involved in PCa progression, and therapeutic inhibition of KDM5C and PSPC1 by selective compounds might be a promising approach for the treatment of PCa.

Correlation of Intra-tumoral and Peripheral PD-1/PD-L1 Immunity in Head and Neck Cancer.

BACKGROUND/AIM: Head and neck squamous cell carcinoma (HNSCC) represents a heterogeneous malignant disease of the oral cavity, pharynx, and larynx. HNSCC cells evade the host immune system through alterations in their immunogenicity, production of immunosuppressive mediators, and induction of immunomodulatory cell types. The immune status of solid HNSCC can be considered as hot, cold, or excluded for each patient individually, based on the distribution of tumor infiltrating immune cells. In this context immunotherapies based on the blockade of checkpoint molecules programmed death 1 (PD-1) and programmed death ligand 1 (PD-L1) have significantly improved therapeutic outcomes in different cancer types. In HNSCC, intra-tumoral expression levels of PD-L1 are used for decision making in checkpoint inhibitor treatment. The significance of PD-L1 as a prognostic indicator is still controversial because both PD-1 and PD-L1 are also expressed in different types of circulating immune cells and the interaction of systemic and intra-tumoral cell-type-specific expression patterns of checkpoint molecules PD-1/PD-L1 has not yet been fully unveiled. MATERIALS AND METHODS: Using immunohistochemical (IHC) staining and flow cytometry, we correlated the expression patterns of the checkpoint molecules PD1/PD-L1 in peripheral blood CD14/CD16 monocytes and CD4/CD8 T cells with intra-tumoral conditions in patients with head and neck cancer. RESULTS/CONCLUSION: Our data demonstrate significant connections between systemic and intra-tumoral PD-1/PD-L1 immune patterns, both of which may serve as promising combined biomarkers for treatment decisions in patients with head and neck cancer.

Experimental in vitro, ex vivo and in vivo models in prostate cancer research.

Androgen deprivation therapy has a central role in the treatment of advanced prostate cancer, often causing initial tumour remission before increasing independence from signal transduction mechanisms of the androgen receptor and then eventual disease progression. Novel treatment approaches are urgently needed, but only a fraction of promising drug candidates from the laboratory will eventually reach clinical approval, highlighting the demand for critical assessment of current preclinical models. Such models include standard, genetically modified and patient-derived cell lines, spheroid and organoid culture models, scaffold and hydrogel cultures, tissue slices, tumour xenograft models, patient-derived xenograft and circulating tumour cell eXplant models as well as transgenic and knockout mouse models. These models need to account for inter-patient and intra-patient heterogeneity, the acquisition of primary or secondary resistance, the interaction of tumour cells with their microenvironment, which make crucial contributions to tumour progression and resistance, as well as the effects of the 3D tissue network on drug penetration, bioavailability and efficacy.

The Identification of CELSR3 and Other Potential Cell Surface Targets in Neuroendocrine Prostate Cancer.

Although recent efforts have led to the development of highly effective androgen receptor (AR)-directed therapies for the treatment of advanced prostate cancer, a significant subset of patients will progress with resistant disease including AR-negative tumors that display neuroendocrine features [neuroendocrine prostate cancer (NEPC)]. On the basis of RNA sequencing (RNA-seq) data from a clinical cohort of tissue from benign prostate, locally advanced prostate cancer, metastatic castration-resistant prostate cancer and NEPC, we developed a multi-step bioinformatics pipeline to identify NEPC-specific, overexpressed gene transcripts that encode cell surface proteins. This included the identification of known NEPC surface protein CEACAM5 as well as other potentially targetable proteins (e.g., HMMR and CESLR3). We further showed that cadherin EGF LAG seven-pass G-type receptor 3 (CELSR3) knockdown results in reduced NEPC tumor cell proliferation and migration in vitro. We provide in vivo data including laser capture microdissection followed by RNA-seq data supporting a causal role of CELSR3 in the development and/or maintenance of the phenotype associated with NEPC. Finally, we provide initial data that suggests CELSR3 is a target for T-cell redirection therapeutics. Further work is now needed to fully evaluate the utility of targeting CELSR3 with T-cell redirection or other similar therapeutics as a potential new strategy for patients with NEPC. Significance: The development of effective treatment for patients with NEPC remains an unmet clinical need. We have identified specific surface proteins, including CELSR3, that may serve as novel biomarkers or therapeutic targets for NEPC.

Toxoplasmosis after allogeneic stem cell transplantation--a single centre experience.

Toxoplasmosis is a rare but possibly underestimated complication following allogeneic stem cell transplantation with a high mortality rate. One reason might be the limitation of the diagnostic instruments relying mainly on imaging and molecular-based techniques. In this report, we present three cases of toxoplasmosis identified among 155 allograft recipients treated at Greifswald University Hospital. Widely disseminated toxoplasmosis was detected post-mortem in two patients allografted for high-risk multiple myeloma. Clinical signs suspicious for toxoplasmosis occurred after days +32 and +75, respectively. In one case, serology and conventional Toxoplasma gondii PCR, targeting the B1 gene, revealed negative results, while in the other patient, toxoplasmosis was not investigated. Both patients received pentamidine for Pneumocystis jirovecii pneumonia (PcP) prophylaxis. The third patient, a 68-year-old woman allografted for AML, developed cerebral toxoplasmosis from day +395 after allogeneic SCT with typical signs in magnetic resonance tomography. Toxoplasma DNA was amplified from one of two samples of cerebrospinal fluid. The patient died of disseminated toxoplasmosis despite immediate initiation of therapy. Retrospective comparative testing of clinical specimens by the conventional T. gondii PCR and by a real-time PCR targeting a 529-bp genomic fragment suggests a higher sensitivity of the latter method in our patients. In conclusion, we suggest a rigorous real-time PCR monitoring for high-risk patients or patients with signs of infections suspicious for toxoplasmosis, even though low-copy results are presently difficult to interpret. Our reported cases might also encourage the use of trimethoprim-sufmethoxazole instead of pentamidine for PcP prophylaxis in those patients.

Histone Demethylase KDM5C Drives Prostate Cancer Progression by Promoting EMT.

Prostate cancer (PCa) poses a major public health problem in men. Metastatic PCa is incurable, and ultimately threatens the life of many patients. Mutations in tumor suppressor genes and oncogenes are important for PCa progression, whereas the role of epigenetic factors in prostate carcinogenesis is insufficiently examined. The histone demethylase KDM5C exerts important roles in tumorigenesis. KDM5C has been reported to be highly expressed in various cancer cell types, particularly in primary PCa. Here, we could show that KDM5C is highly upregulated in metastatic PCa. Functionally, in KDM5C knockdown cells migratory and invasion capacity was reduced. Interestingly, modulation of KDM5C expression influences several EMT signaling pathways (e.g., Akt/mTOR), expression of EMT transcription factors, epigenetic modifiers, and miR-205, resulting in increased expression of E-cadherin and reduced expression of N-cadherin. Mouse xenografts of KDM5C knockdown cells showed reduced tumor growth. In addition, the Akt/mTOR pathway is one of the classic signaling pathways to mediate tumor metabolic homeostasis, which is beneficial for tumor growth and metastasis. Taken together, our findings indicate that a combination of a selective KDM5C- and Akt/mTOR-inhibitor might be a new promising therapeutic strategy to reduce metastatic burden in PCa.