INTRODUCTION: Renal cell carcinoma (RCC) is one of the most prevalent cancers in kidney transplant recipients (KTR). The hereditary background of RCC in native kidneys has been determined, implicating its clinical importance. MATERIALS AND METHODS: This retrospective single-center pilot study aimed to identify a potential genetic predisposition to RCC of the transplanted kidney and outcome in KTR who underwent single kidney transplantation between January 2000 and December 2020 and manifested RCC of the transplanted kidney. Next-generation sequencing (NGS) based germline genetic analysis from peripheral blood-derived genomic DNA (gDNA) was performed in both the recipient and donor using a gene panel targeting 226 cancer predisposition genes. RESULTS: The calculated incidence of RCC of the transplanted kidney among 4146 KTR was 0.43%. In fifteen KTR and donors, NGS was performed. The mean KTR age at transplantation and the diagnosis of RCC was 50.3 years (median 54; 5-67 years) and 66 years (median 66; 24-79 years), respectively. The mean donor age at transplantation and graft age at RCC diagnosis was 39.7 years (median 42; 7-68 years) and 50.2 years (median 46; 20-83 years), respectively. The mean follow-up after RCC diagnosis was 47 months (median 39.1; 0-112 months). Papillary RCC was the most prevalent (n = 8), followed by clear cell RCC (n = 6) and unspecified RCC (n = 1). Thirteen RCCs were low-stage (pT1a/b) diseases, one was pT3, and one was of unknown stage. Most RCC was higher graded. No germline pathogenic cancer-predisposition variant was found in either KTR or donors except for several variants of uncertain significance. CONCLUSION: RCC of the transplanted kidney is very rare. Germline cancer-predisposition testing has identified several variants of uncertain significance, but no germline genetic predisposition to graft RCC in KTR. Further research is needed to assess the clinical relevance of genetic testing for cancer risk in KTR.

• MeSH
• Tissue Donors MeSH
• Child MeSH
• Adult MeSH
• Genetic Predisposition to Disease MeSH
• Carcinoma, Renal Cell * genetics   MeSH
• Middle Aged MeSH
• Humans MeSH
• Adolescent MeSH
• Young Adult MeSH
• Kidney Neoplasms * genetics   MeSH
• Pilot Projects MeSH
• Child, Preschool MeSH
• Retrospective Studies MeSH
• Aged, 80 and over MeSH
• Aged MeSH
• Kidney Transplantation * adverse effects   MeSH
• High-Throughput Nucleotide Sequencing MeSH
• Check Tag
• Child MeSH
• Adult MeSH
• Middle Aged MeSH
• Humans MeSH
• Adolescent MeSH
• Young Adult MeSH
• Male MeSH
• Child, Preschool MeSH
• Aged, 80 and over MeSH
• Aged MeSH
• Female MeSH
• Publication type
• Journal Article MeSH

The subset of ovarian cancer (OC) diagnosed ≤ 30yo represents a distinct subgroup exhibiting disparities from late-onset OC in many aspects, including indefinite germline cancer predisposition. We performed DNA/RNA-WES with HLA-typing, PRS assessment and survival analysis in 123 early-onset OC-patients compared to histology/stage-matched late-onset and unselected OC-patients, and population-matched controls. Only 6/123(4.9%) early-onset OC-patients carried a germline pathogenic variant (GPV) in high-penetrance OC-predisposition genes. Nevertheless, our comprehensive germline analysis of early-onset OC-patients revealed two divergent trajectories of potential germline susceptibility. Firstly, overrepresentation analysis highlighted a connection to breast cancer (BC) that was supported by the CHEK2 GPV enrichment in early-onset OC(p = 1.2 × 10-4), and the presumably BC-specific PRS313, which successfully stratified early-onset OC-patients from controls(p = 0.03). The second avenue pointed towards the impaired immune response, indicated by LY75-CD302 GPV(p = 8.3 × 10-4) and diminished HLA diversity compared with controls(p = 3 × 10-7). Furthermore, we found a significantly higher overall GPV burden in early-onset OC-patients compared to controls(p = 3.8 × 10-4). The genetic predisposition to early-onset OC appears to be a heterogeneous and complex process that goes beyond the traditional Mendelian monogenic understanding of hereditary cancer predisposition, with a significant role of the immune system. We speculate that rather a cumulative overall GPV burden than specific GPV may potentially increase OC risk, concomitantly with reduced HLA diversity.

• Keywords
• Early-onset, Germline whole exome sequencing, HLA, Mutation burden, Ovarian cancer, Polygenic risk score,
• MeSH
• Checkpoint Kinase 2 genetics   MeSH
• Adult MeSH
• Genetic Predisposition to Disease * MeSH
• Middle Aged MeSH
• Humans MeSH
• Young Adult MeSH
• Ovarian Neoplasms * genetics   MeSH
• Case-Control Studies MeSH
• Age of Onset * MeSH
• Germ-Line Mutation * MeSH
• Check Tag
• Adult MeSH
• Middle Aged MeSH
• Humans MeSH
• Young Adult MeSH
• Female MeSH
• Publication type
• Journal Article MeSH
• Names of Substances
• Checkpoint Kinase 2 MeSH

The MRE11, RAD50, and NBN genes encode for the nuclear MRN protein complex, which senses the DNA double strand breaks and initiates the DNA repair. The MRN complex also participates in the activation of ATM kinase, which coordinates DNA repair with the p53-dependent cell cycle checkpoint arrest. Carriers of homozygous germline pathogenic variants in the MRN complex genes or compound heterozygotes develop phenotypically distinct rare autosomal recessive syndromes characterized by chromosomal instability and neurological symptoms. Heterozygous germline alterations in the MRN complex genes have been associated with a poorly-specified predisposition to various cancer types. Somatic alterations in the MRN complex genes may represent valuable predictive and prognostic biomarkers in cancer patients. MRN complex genes have been targeted in several next-generation sequencing panels for cancer and neurological disorders, but interpretation of the identified alterations is challenging due to the complexity of MRN complex function in the DNA damage response. In this review, we outline the structural characteristics of the MRE11, RAD50 and NBN proteins, the assembly and functions of the MRN complex from the perspective of clinical interpretation of germline and somatic alterations in the MRE11, RAD50 and NBN genes.

• Keywords
• ATLD, DNA repair, MRE11, NBN, NBS, NBSLD, NGS, RAD50, TP53, hereditary cancer syndromes, variant interpretation,
• MeSH
• Ataxia Telangiectasia Mutated Proteins genetics   metabolism   MeSH
• DNA-Binding Proteins genetics   metabolism   MeSH
• DNA Repair Enzymes genetics   metabolism   MeSH
• MRE11 Homologue Protein genetics   metabolism   MeSH
• Acid Anhydride Hydrolases genetics   metabolism   MeSH
• Nuclear Proteins genetics   metabolism   MeSH
• Humans MeSH
• Tumor Suppressor Proteins * genetics   MeSH
• DNA Repair genetics   MeSH
• Cell Cycle Proteins * metabolism   MeSH
• Check Tag
• Humans MeSH
• Publication type
• Journal Article MeSH
• Review MeSH
• Names of Substances
• Ataxia Telangiectasia Mutated Proteins MeSH
• DNA-Binding Proteins MeSH
• DNA Repair Enzymes MeSH
• MRE11 Homologue Protein MeSH
• Acid Anhydride Hydrolases MeSH
• Nuclear Proteins MeSH
• Tumor Suppressor Proteins * MeSH
• NBN protein, human MeSH Browser
• Cell Cycle Proteins * MeSH
• RAD50 protein, human MeSH Browser