Introduction: DNA methylation is an epigenetic event that occurs in normal tissues but changes in both the early and late stages of multiple tumor entities, including renal cell cancer (RCC). Many studies have shown that DNA methylation markers are relevant to RCC prognosis, but none of these markers have entered into clinical routine. Furthermore, because of its potential reversibility, DNA methylation might provide a new target for RCC therapy strategies. Materials and methods: Following PRISMA guidelines, we performed a systematic literature search up to February 2019. After selection for eligibility, a total of 56 studies were identified for analysis. Each study was categorized and the level of evidence assessed. Only articles reporting on DNA methylation markers and their association with survival were included. Descriptive statistical analyses were conducted with R statistical software. Results: We identified promoter methylation of SFRP1, GATA5, NEFH, GREM1, and BCN1 as associated with survival in RCC. Moreover, we found evidence that methylation signatures, i.e., grouping of different potential gene markers, might be of better prognostic value than single gene marker investigations. Nevertheless, because of the heterogeneous features of the studies in terms of design, methodology, patient cohorts, and statistics, the true clinical impact of these methylation markers for prognosis in RCC patients remains uncertain. Conclusion: This systematic review elucidates the potential impact of DNA methylation on survival of patients with RCC. Several promising prognostic markers, especially methylation signatures, were identified, which is encouraging, but prospective validations are necessary to establish their true clinical value.

The detection of DNA methylation in primary tumor tissues could be relevant for early stratification of aggressive renal cell carcinomas (RCCs) as a basis for future personalized adjuvant therapy. Methylated TCGA KIRC based candidate CpG loci in INA, NHLH2, and THBS4 that are possibly associated with RCC metastasis were evaluated by pyrosequencing in 154 paired normal adjacent and primary tumor tissues, as well as in 202 metastatic tissues. Statistical analysis was carried out by bivariate logistic regression for group comparisons, log rank survival analysis, and unsupervised and supervised analysis for the classification of tumors. Increased methylation of INA, NHLH2, and THBS4 loci were significantly associated with distant metastasis in primary tumors (p < 0.05), tissue-specific hypermethylation in metastatic (p = 7.88 × 10−8, 5.57 × 10−10, 2.06 × 10−7) and tumor tissues (p = 3.72 × 10−24, 3.17 × 10−13, 1.58 × 10−19), and shortened progression free survival in patients (p = 0.03). Combined use of CpG site-specific methylation permits the discrimination of tissues with metastatic disease and reveals a significant contribution of CpG sites in all genes to the statistical classification model. Thus, metastasis in RCC is significantly associated with methylation alterations in INA, NHLH2, and THBS4 loci, providing independent information for the potential early detection of aggressive renal cancers as a rationale for stratifying patients to adjuvant therapies.

Photodynamic antimicrobial chemotherapy (PACT) is a multi-target method to inactivate pathogenic microorganisms by exciting a photosensitizer (PS) with visible light of appropriate wavelength in the presence of molecular oxygen (O). There are two major pathways by which reactive oxygen species (ROS) are produced. In type I (T)-reactions, radicals such as superoxide (O˙) and hydroxyl radicals (˙OH) are generated by electron transfer. In type II (T)-reactions, highly reactive singlet oxygen (O) is produced by direct energy transfer. This study investigated the efficiency of PACT in Gram-negative Escherichia coli wild type (EC WT) and the mutant Escherichia coli PN134 (EC PN134) which is not able to produce SOD A and SOD B, by means of two different photosensitizers (PS) from different chemical classes with different O quantum yields: methylene blue (MB) and 5,10,15,20-tetrakis(1-methyl-4-pyridinio)porphyrin tetra(p-toluenesulfonate) (TMPyP). Mutants, which lack antioxidant enzymes, were particularly susceptible towards T-PACT. In the case of PACT with MB, quenching agents such as superoxide dismutase (SOD) and catalase (CAT) were sufficient for protecting both the wild type and the mutant, whereas they were not in PACT with TMPyP. The genetic levels of sodA and sodB were examined after photodynamic treatment regarding their potential resistance. This study showed that - under the photodynamic conditions presented in this study - expression of sodA and sodB was not directly influenced by PACT-generated oxidative stress, although SOD enzymes are part of the major defense machinery against oxidative stress and were thus expected to be upregulated. Overall the susceptibility of EC PN134 and EC WT differed towards photodynamic inactivation via T-mechanism of action. Thus, already existing defense mechanisms against ROS in bacteria might influence the susceptibility against T-PACT, while this was not the case using T-photosensitizers.

Introduction: The corticotropin-releasing hormone (CRH) system, its receptors corticotropinreleasing hormone receptor 1 (CRHR1) and 2 (CRHR2), and its corresponding binding protein corticotropin-releasing hormone-binding protein (CRHBP) as well as the urocortin proteinsstructural homologues to CRH, which are included in this peptide family-have become interesting oncological targets recently. Carcinogenesis of various human tumors has been reported with an altered presence of members of this system. The aim of the present study was to examine the role of urocortin 3 (UCN3) in renal cell carcinoma (RCC). Methods: Therefore, tumoral tissues of 106 patients with RCC and available corresponding normal tissues were analyzed using qPCR for quantitative mRNA expression analysis. Tissue localization and protein signals of UCN3 in normal and tumoral renal specimens were evaluated using western blot and immunohistochemistry. In addition, correlation studies of UCN3 mRNA expression with clinicopathological parameters of patients with RCC and different histological subtypes were evaluated. Results: UCN3 mRNA was significantly downregulated in nearly all tumoral tissues (p = 7.92 9 10-13). The same effect was observed at protein level using immunohistochemistry. Level of UCN3 mRNA expression was not directly correlated with clinicopathological parameters. Conclusion: We report for the first time the significant downregulation of UCN3 in RCC. These results demonstrate a possible involvement of the CRH system and its significance in carcinogenesis of RCC.

Background DNA methylation is frequently observed in the development and progression of many human tumors as well as renal cell cancer (RCC). Tumor Associated Calcium Signal Transducer 2 (TACSTD2) participates in cell cycle progression through MAPK signalling pathway activation. Moreover, tumor-specific hypermethylation and association with aggressive cancer characteristics has been found for lung adenocarcinoma, hepatocellular carcinoma and cholangiocarcinoma. Whether TACSTD2 is tumor specifically hypermethylated in RCC or shows association of methylation with adverse clinicopathological parameters and survival of patients has not been investigated at yet. Methods Quantitative methylation-specific PCR (qMSP) analysis of a locus in the intron 1 region of TACSTD2 gene was carried out in a cross-sectional study of 127 paired RCC and normal samples. In silico analysis of TACSTD2 methylation in the TCGA Kidney Renal Clear Cell Carcinoma (KIRC) dataset of 280 patients served as validation cohort. Statistical analyses were carried out using the two-sided paired t-test for matched tumor and normal sample comparisons, logistic regression for subgroup comparisons, Cox regression for analysis of recurrence free survival (RFS) and Pearson correlation analysis for correlation of TACSTD2 methylation and TACSTD2 mRNA in KIRC data. Results Higher methylation levels in RCC were significantly associated with advanced disease (p < 0.001), high tumor stage (p = 0.003), tumor differentiation (p = 0.033) and presence of lymph node (p = 0.021) or distant metastases (p = 0.008). TACSTD2 hypermethylation was associated with a shorter RFS of patients and demonstrate statistical independency from clinical parameters as state of metastasis, tumor stage, grade and state of advanced disease. In silico validation using TCGA KIRC data also demonstrated association of TACSTD2 loci with adverse clinicopathology and shortened RFS of patients. In addition, in silico analyses of TCGA KIRC data showed an inverse correlation between DNA methylation levels of TACSTD2 and mRNA expression. Conclusions Our results suggest an association between TACSTD2 methylation and disease progression and clinical course of RCC.