Two percent of patients with Wilms tumors have a positive family history. In many of these cases the genetic cause remains unresolved. By applying germline exome sequencing in two families with two affected individuals with Wilms tumors, we identified truncating mutations in TRIM28. Subsequent mutational screening of germline and tumor DNA of 269 children affected by Wilms tumor was performed, and revealed seven additional individuals with germline truncating mutations, and one individual with a somatic truncating mutation in TRIM28. TRIM28 encodes a complex scaffold protein involved in many different processes, including gene silencing, DNA repair and maintenance of genomic integrity. Expression studies on mRNA and protein level showed reduction of TRIM28, confirming a loss‐of‐function effect of the mutations identified. The tumors showed an epithelial‐type histology that stained negative for TRIM28 by immunohistochemistry. The tumors were bilateral in six patients, and 10/11 tumors are accompanied by perilobar nephrogenic rests. Exome sequencing on eight tumor DNA samples from six individuals showed loss‐of‐heterozygosity (LOH) of the TRIM28‐locus by mitotic recombination in seven tumors, suggesting that TRIM28 functions as a tumor suppressor gene in Wilms tumor development. Additionally, the tumors showed very few mutations in known Wilms tumor driver genes, suggesting that loss of TRIM28 is the main driver of tumorigenesis. In conclusion, we identified heterozygous germline truncating mutations in TRIM28 in 11 children with mainly epithelial‐type Wilms tumors, which become homozygous in tumor tissue. These data establish TRIM28 as a novel Wilms tumor predisposition gene, acting as a tumor suppressor gene by LOH.

Diagnosing ADTKD- by molecular genetics is possible, but it is technically demanding and labor intensive. However, immunohistochemistry on kidney biopsy specimens is feasible for nongenetic diagnosis of ADTKD- and therefore, a valid method to select families for further diagnostics. Our data are compatible with the hypothesis that specific molecular effects of MUC1-fs underlie the pathogenesis of this disease.

BackgroundLaryngeal squamous cell carcinoma (LSCC) is the second most common cancer of the head and neck. In order to identify differentially expressed genes which may have a role in LSCC carcinogenesis, we performed GeneFishing Assay. One of the differentially expressed genes was the SLC22A23 (solute carrier family 22, member 23) gene.SLC22A23 belongs to a family of organic ion transporters that are responsible for the absorption or excretion of many drugs, xenobiotics and endogenous compounds in a variety of tissues. SLC22A23 is expressed in a various tissues but no substrates or functions have been identified for it. Although the exact function is unknown, single nucleotide polymorphisms (SNPs) which are located in SLC22A23 gene were associated with inflammatory bowel disease (IBD), endometriosis-related infertility and the clearance of antipsychotic drugs. On the other hand SLC22A23 is identified as a prognostic gene to predict the recurrence of triple-negative breast cancer.MethodsTo understand the role of the SLC22A23 gene in laryngeal carcinogenesis, we investigated its mRNA expression level in laryngeal tumor tissue and adjacent non-cancerous tissue samples obtained from 83 patients by quantitative real-time PCR. To understand the association between SNPs in SLC22A23 and LSCC, selected genetic variations (rs4959235, rs6923667, rs9503518) were genotyped.ResultsWe found that SLC22A23 expression was increased in 46 of 83 tumor tissues (55.4%) and was decreased in 30 of 83 (36.1%) tumor tissues compared to normal tissues. 77.2% of patients were homozygote for genotype rs9503518-AA and they most frequently had histological grade 2 and 3 tumors. We also found that rs9503518-AA genotype is associated with increased SLC22A23 expression.ConclusionsOur results indicate that SLC22A23 may play a role in the development of laryngeal cancer.

Although there are extensive studies on the genetics of bladder cancer, several questions remain unanswered. One of the pathways which are altered in bladder cancer is the mTOR signaling pathway. In the present study, we analyzed the expression of Rheb gene and genetic alterations in the LKB1 gene which are the key components of mTOR pathway. Nine exons of the LKB1 gene were analyzed by direct sequencing in 51 bladder cancer patients. To investigate the expression of Rheb and LKB1, real-time quantitative RT-PCR was performed in bladder tumor and normal bladder tissue samples. We did not observed a statistically significant difference in Rheb or LKB1 expression between the tumor and normal tissue samples. We detected a novel missense mutation creating stop codon in a high percent of the tumor samples. Five different single nucleotide substitutions were also observed in the introns. Our results indicate that LKB1 gene may play a role in the progression of bladder cancer.