The heterogeneous cancer phenotype of individuals with biallelic germline pathogenic variants in CHEK2.

PURPOSE: Females with biallelic CHEK2 germline pathogenic variants (gPVs) more often develop multiple breast cancers than individuals with monoallelic CHEK2 gPVs. This study is aimed at expanding the knowledge on the occurrence of other malignancies. METHODS: Exome sequencing of individuals who developed multiple primary malignancies identified 3 individuals with the CHEK2 (NM_007194.4) c.1100del p.(Thr367MetfsTer15) loss-of-function gPV in a biallelic state. We collected the phenotypes of an additional cohort of individuals with CHEK2 biallelic gPVs (n = 291). RESULTS: In total, 157 individuals (53.4%; 157/294 individuals) developed ≥1 (pre)malignancy. The most common (pre)malignancies next to breast cancer were colorectal- (n = 19), thyroid- (n = 19), and prostate (pre)malignancies (n = 12). Females with biallelic CHEK2 loss-of-function gPVs more frequently developed ≥2 (pre)malignancies and at an earlier age compared with females biallelic for the CHEK2 c.470T>C p.(Ile157Thr) missense variant. Furthermore, 26 males (31%; 26/84 males) with CHEK2 biallelic gPVs developed ≥1 (pre)malignancies of 15 origins. CONCLUSION: Our study suggests that CHEK2 biallelic gPVs likely increase the susceptibility to develop multiple malignancies in various tissues, both in females and males. However, it is possible that a substantial proportion of individuals with CHEK2 biallelic gPVs is missed as diagnostic testing for CHEK2 often is limited to individuals who developed breast cancer.

The Different Immune Profiles of Normal Colonic Mucosa in Cancer-Free Lynch Syndrome Carriers and Lynch Syndrome Colorectal Cancer Patients.

BACKGROUND & AIMS: Owing to the high load of immunogenic frameshift neoantigens, tumors arising in individuals with Lynch syndrome (LS), the most common inherited colorectal cancer (CRC) syndrome, are characterized by a pronounced immune infiltration. However, the immune status of normal colorectal mucosa in LS is not well characterized. We assessed the immune infiltrate in tumor-distant normal colorectal mucosa from LS CRC patients, sporadic microsatellite-unstable (MSI) and microsatellite-stable (MSS) CRC patients, and cancer-free LS carriers. METHODS: CD3-positive, FOXP3-positive, and CD8-positive T cells were quantified in, respectively, 219, 233, and 201 formalin-fixed paraffin-embedded (FFPE) normal colonic mucosa tissue sections from CRC patients and cancer-free LS carriers and 26, 22, and 19 LS CRCs. CD3-positive T cells were also quantified in an independent cohort of 97 FFPE normal rectal mucosa tissue sections from LS carriers enrolled in the CAPP2 clinical trial. The expression of 770 immune-relevant genes was analyzed in a subset of samples with the use of the NanoString nCounter platform. RESULTS: LS normal mucosa specimens showed significantly elevated CD3-, FOXP3-, and CD8-positive T-cell densities compared with non-LS control specimens. Gene expression profiling and cluster analysis revealed distinct immune profiles in LS carrier mucosa with and without cancer manifestation. Long-term follow-up of LS carriers within the CAPP2 trial found a correlation between mucosal T-cell infiltrate and time to subsequent tumor occurrence. CONCLUSIONS: LS carriers show elevated mucosal T-cell infiltration even in the absence of cancer. The normal mucosa immune profile may be a temporary or permanent tumor risk modifier in LS carriers.

OnkoRiskNET: a multicenter, interdisciplinary, telemedicine-based model to improve care for patients with a genetic tumor risk syndrome.

BACKGROUND: Genetic tumor risk syndromes are responsible for at least five to ten percent of the 4 million cases of cancer diagnosed in Europe every year. Currently, the care of oncological patients suffers from a lack of specialists in medical genetics and also a lack of access to genetic care in rural areas and structured care pathways between oncologists and medical geneticists. As a result, genetic tumor risk syndromes are underdiagnosed with potentially fatal consequences for patients and their families. METHODS: The OnkoRiskNET study is supported by a grant from the Federal Joint Committee of the Federal Republic of Germany. The study will include 2,000 oncological index patients from oncology practices in Lower Saxony and Saxony after the start of the study in July 2021. Randomization is carried out by means of a stepped wedge design at the level of the practices. Patients either go through routine care or the new form of care with structured cooperation between medical geneticists and oncologists, case management and the use of telemedical genetic counseling. Using a mixed-methods approach, the following parameters will be evaluated in the control and intervention group: (1) Conducted genetic counseling sessions by patients with suspected tumor risk syndrome and their first degree relatives; (2) Patient satisfaction and psychological distress after genetic counseling and testing; (3) Factors influencing the acceptance and experience of telemedical genetic counseling; (4) Satisfaction of oncologists and medical genetics with the structured pathway; (5) Cost efficiency of the new form of care. DISCUSSION: OnkoRiskNET aims to close the gap in care through the formation of a cooperation network between practicing oncologists and specialists in medical genetics and the use of telemedical genetic counseling, thereby, increasing the diagnostic rate in genetic tumor risk syndromes and serving as a model for future genetic care in Germany. TRIAL REGISTRATION: Trial was registered on 01.12.2021 in the German Clinical Trial Register ( https://trialsearch.who.int/ ) with the DRKS-ID:  DRKS00026679 . TITLE: Cooperation network for the provision of local care for patients and families with a genetic tumour risk syndrome. Trial acronym: OnkoRiskNET. Protocol version 1.1.

Novel genetic characterisation and phenotype correlation in von Hippel-Lindau (VHL) disease based on the Elongin C binding site: a large retrospective study.

BACKGROUND: Von Hippel-Lindau (VHL) disease is an autosomal dominant genetic tumour syndrome resulting from mutations in the VHL gene lineage, and its prognosis is generally poor. This study aimed to provide a more valuable genotype-phenotype correlation based on the Elongin C binding site in VHL disease. METHODS: This study included 553 patients (194 families) who were diagnosed with VHL disease in our centre from September 2010 to February 2019. According to the type of gene mutation, the patients were divided into the Elongin C binding site missense mutation (EM) group, the non-Elongin C binding site missense mutation (nEM) group and the truncation mutation (TR) group. We analysed and compared the age-related tumour risk and prognosis of the three groups. RESULTS: A total of 14 new intragenic mutations were found in this cohort. The age-related risk of central nervous system haemangioblastoma (CHB) and pancreatic tumour in the EM group was lower than in the combined nEM-TR group, while the corresponding risk of pheochromocytoma (PHEO) was higher. Additionally, the prognoses of EM and nEM-TR were analysed. The median survival period in the EM group was longer than that in the nEM-TR group, and both the total survival and the CHB-specific survival of the EM group were better than those of the nEM-TR group. CONCLUSION: In conclusion, our study demonstrated that the EM was an independent risk factor for PHEO. The EM is also an independent protective factor for CHB age-related risk, overall survival and CHB-specific survival in VHL disease. This modified genotype-phenotype correlation integrates gene mutation, the Elongin B binding site, and phenotypic diversity and provides a reference for clinical diagnosis.

Genotype and phenotype correlation in von Hippel-Lindau disease based on alteration of the HIF-α binding site in VHL protein.

PURPOSE: Von Hippel-Lindau (VHL) disease is a rare hereditary cancer syndrome that reduces life expectancy. We aimed to construct a more valuable genotype-phenotype correlation based on alterations in VHL protein (pVHL). METHODS: VHL patients (n = 339) were recruited and grouped based on mutation types: HIF-α binding site missense (HM) mutations, non-HIF-α binding site missense (nHM) mutations, and truncating (TR) mutations. Age-related risks of VHL-associated tumors and patient survival were compared. RESULTS: Missense mutations conferred an increased risk of pheochromocytoma (HR = 1.854, p = 0.047) compared with truncating mutations. The risk of pheochromocytoma was lower in the HM group than in the nHM group (HR = 0.298, p = 0.003) but was similar between HM and TR groups (HR = 0.901, p = 0.810). Patients in the nHM group had a higher risk of pheochromocytoma (HR = 3.447, p < 0.001) and lower risks of central nervous system hemangioblastoma (CHB) (HR = 0.700, p = 0.045), renal cell carcinoma (HR = 0.610, p = 0.024), and pancreatic tumor (HR = 0.382, p < 0.001) than those in the combined HM and TR (HMTR) group. Moreover, nHM mutations were independently associated with better overall survival (HR = 0.345, p = 0.005) and CHB-specific survival (HR = 0.129, p = 0.005) than HMTR mutations. CONCLUSION: The modified genotype-phenotype correlation links VHL gene mutation, substrate binding site, and phenotypic diversity (penetrance and survival), and provides more accurate information for genetic counseling and pathogenesis studies.

Cancer Risk in Beckwith-Wiedemann Syndrome: A Systematic Review and Meta-Analysis Outlining a Novel (Epi)Genotype Specific Histotype Targeted Screening Protocol.

OBJECTIVE: To compare tumor risk in the 4 Beckwith-Wiedemann syndrome (BWS) molecular subgroups: Imprinting Control Region 1 Gain of Methylation (ICR1-GoM), Imprinting Control Region 2 Loss of Methylation (ICR2-LoM), Chromosome 11p15 Paternal Uniparental Disomy (UPD), and Cyclin-Dependent Kinase Inhibitor 1C gene (CDKN1C) mutation. STUDY DESIGN: Studies on BWS and tumor development published between 2000 and 2015 providing (epi)genotype-cancer correlations with histotype data were reviewed and meta-analysed with cancer histotypes as measured outcome and (epi)genotype as exposure. RESULTS: A total of 1370 patients with BWS were included: 102 developed neoplasms (7.4%). Tumor prevalence was 2.5% in ICR2-LoM, 13.8% in UPD, 22.8% in ICR1-GoM, and 8.6% in patients with CDKN1C mutations. Cancer ORs were 12.8 in ICR1-GoM, 6.5 in UPD, and 2.9 in patients with CDKN1C mutations compared with patients with ICR2-LoM. Wilms tumor was associated with ICR1-GoM (OR 68.3) and UPD (OR 13.2). UPD also was associated with hepatoblastoma (OR 5.2) and adrenal carcinoma (OR 7.0), and CDKN1C mutations with neuroblastic tumors (OR 7.2). CONCLUSION: Cancer screening in BWS could be differentiated on the basis of (epi)genotype and target specific histotypes. Patients with ICR1-GoM and UPD should undergo renal ultrasonography scanning, given their risk of Wilms tumor. Alpha feto protein monitoring for heptaoblastoma is suggested in patients with UPD. Adrenal carcinoma may deserve screening in patients with UPD. Patients with CDKN1C mutations may deserve neuroblastoma screening based on urinary markers and ultrasonography scanning. Finally, screening appears questionable in cases of ICR2-LoM, given low tumor risk.

Impact of head morphology on local brain specific absorption rate from exposure to mobile phone radiation.

Among various possible health effects of mobile phone radiation, the risk of inducing cancer has the strongest interest of laymen and health organizations. Recently, the Interphone epidemiological study investigated the association between the estimated Radio Frequency (RF) dose from mobile phones and the risk of developing a brain tumor. Their dosimetric analysis included over 100 phone models but only two homogeneous head phantoms. So, the potential impact of individual morphological features on global and local RF absorption in the brain was not investigated. In this study, we performed detailed dosimetric simulations for 20 head models and quantified the variation of RF dose in different brain regions as a function of head morphology. Head models were exposed to RF fields from generic mobile phones at 835 and 1900 MHz in the "tilted" and "cheek" positions. To evaluate the local RF dose variation, we used and compared two different post-processing methods, that is, averaging specific absorption rate (SAR) over Talairach regions and over sixteen predefined 1 cm(3) cube-shaped field-sensors. The results show that the variation in the averaged SAR among the heads can reach up to 16.4 dB at a 1 cm(3) cube inside the brain (field-sensor method) and alternatively up to 15.8 dB in the medulla region (Talairach method). In conclusion, we show head morphology as an important uncertainty source for dosimetric studies of mobile phones. Therefore, any dosimetric analysis dealing with RF dose at a specific region in the brain (e.g., tumor risk analysis) should be based upon real morphology.

A novel signature of seven aging-related genes for risk stratification, prognosis prediction and benefit evaluation of chemotherapy, and immunotherapy in elderly patients with lung adenocarcinoma.

Background: Aging, a multifaceted biological process, is thought to be associated with lung adenocarcinoma (LUAD) development and progression. However, it is unclear whether aging-related genes (ARGs) can predict tumor risk, chemotherapy and immunotherapy benefits, and prognosis in LUAD patients at different ages. Methods: Gene expression datasets and clinical information of LUAD patients were downloaded from TCGA and GEO database. Univariate and multivariate Cox regression, and lasso algorithm were employed to identify the ARG signatures. Patients were stratified into high-risk and low-risk groups to evaluate the predictive accuracy using Kaplan-Meier curves, ROC curves, and time-dependent AUC. A nomogram was established to predict the survival probability. GSEA revealed potential pathways, and CIBERSORT indicated different immunologic status. TIDE score was used to predict the potential tumor response to immune checkpoint inhibitors, and GDSC was employed to evaluate the sensitivity of chemotherapeutic drugs. The correlation of TIDE score and patient age, as well as that of ARGs and patient age was investigated. And cell Culture and RT-qPCR for external validation for key gene. Results: A novel gene signature based on seven ARGs was established, including BMP15, CD79A, CDKN3, CDX2, COL1A1, DKK1, and GRIK2. Our model demonstrated exceptional prediction accuracy for elderly LUAD patients of 71-90 years old. A nomogram model was constructed to predict the survival probability, and the C-index value was 0.737, indicating our prognostic nomogram model has high accuracy. Through external RT-qPCR validation, we found that CD79A expression in H1299 was higher than that of BEAS-2B. And novel immunotherapy and chemotherapy regimens were accordingly proposed for the elderly LUAD patients. Conclusion: We identified a novel gene signature based on seven ARGs for risk stratification, prognosis prediction and benefit evaluation of immunotherapy and chemotherapy in elderly LUAD patients.

[Differences in sexual development-S2k guideline update]. / Varianten der Geschlechtsentwicklung ­ Aktualisierung der S2k-Leitlinie.

BACKGROUND: Human beings with a difference in sexual development (DSD) often underwent gender reassignment surgery during early childhood. However, the medical decision was often not congruent with the gender identity that affected persons developed later on. OBJECTIVES: To represent the interests of affected persons, an interdisciplinary guideline in cooperation with support groups was written. MATERIALS AND METHODS: The revision of the first version of the guideline, published in 2016, was edited by 18 professional societies and working groups as well as 3 support groups. A literature search was performed for each of the 12 chapters. Recommendations and statements created by the working groups were voted on during four consensus conferences. RESULTS: The guideline highlights the right of self-determination of affected persons. In this context, new legal requirements are reported. Other than necessary primary diagnostics, medical procedures should be postponed. Most important is the psychological support of parents and patients. Tumor risk of the gonads and protection of fertility are analyzed and discussed in detail. CONCLUSION: The content of the guideline represents a paradigm shift in dealing with human beings with a difference of sexual development. Projects as DSD Care and Empower-DSD help to promote the practical implementation of the guideline's recommendations.

DSD/intersex: historical context and current perspectives.

Intersex/Disorders/Differences of sex development conditions have been recognized for millennia. An organized approach was adopted in the 1960-70s using the philosophy that gender identity was fluid and malleable. Consequences of this approach were the lack of disclosure, stigmatization, and excessive surgery to "normalize" the genitalia. Often this led to quality of life issues for those patients. There have been many modifications in approach since then to avoid the problems noted. There is consensus on many of these changes (e.g. disclosure) but continued controversy on others (e.g. the benefits of early surgery). This review summarizes the historical context and the current areas of consensus and controversy.

Investigation of the factors influencing surgical treatment of duodenal gastrointestinal stromal tumors.

BACKGROUND: Duodenal gastrointestinal stromal tumor (DGIST) is a rare tumor with a specific anatomic site and biological characteristics. As the incidence of lymph node metastasis is very low, the main treatment method is surgery. Two main surgical techniques (local resection and Whipple) are performed in patients with DGISTs. The critical question is which surgical technique to choose. AIM: To identify factors influencing the choice of surgery for DGISTs. METHODS: The clinicopathological data of patients with DGISTs who underwent surgery between January 1999 and January 2021 were analyzed. We used the Student's t-test or Mann-Whitney U-test and the χ 2 test or Fisher's exact test to determine the differences between the two groups of patients. Furthermore, we used logistic analysis to identify the relevant factors and independent factors related to the type of surgery. The Kaplan-Meier method was used to analyze the patient's survival information and Cox regression analysis was performed to determine prognostic risk factors. RESULTS: Overall, 86 patients were analyzed, including 43 men (50%) and 43 women (50%). We divided the patients into two groups based on surgical technique (local resection or Whipple surgery). There were no differences in the age, mitotic figures, and complications between the two groups; however, the tumor size, tumor location, risk grade, postoperative hospital stay, and abdominal drainage time were significantly different. Based on univariate logistic analysis, the Whipple procedure was chosen if the tumor size was ≥ 5.0 cm, the tumor was located in the descending part of the duodenum, or the risk grade was medium or high. In our research, the five-year overall survival rate of patients was more than 90%. We also describe two DGIST patients with liver metastases at first diagnosis and analyzed their management in order to provide advice on complicated cases. CONCLUSION: The Whipple procedure was performed if the primary tumor was in the descending part of the duodenum, tumor size was ≥ 5.0 cm, or the tumor risk grade was medium or high.

The Genotype-Phenotype Association of Von Hipple Lindau Disease Based on Mutation Locations: A Retrospective Study of 577 Cases in a Chinese Population.

PURPOSE: Von Hippel-Lindau (VHL) disease is a hereditary kidney cancer syndrome, with which patients are more likely to get affected by renal cell carcinoma (RCC), pancreatic cyst or tumor (PCT), central nervous system hemangioblastoma (CHB), retinal angiomas (RA), and pheochromocytoma (PHEO). Mutations of VHL gene located in 3p25 may impair the function of the VHL protein and lead to the disease. It's unclear why obvious phenotype varieties exist among VHL patients. Here we aimed to ascertain whether the mutation types and locations affect the phenotype. METHODS: We enrolled 577 Chinese VHL patients from 211 families and divided them into three groups and six subgroups according to their mutation types and locations. Cox survival analysis and Kaplan-Meier analysis were used to compare intergroup age-related tumor risks. RESULTS: Patients with nonsense or frameshift mutations that were located before residues 117 of VHL protein (NoF1 subgroup) hold lower age-related risks of VHL associated tumors (HR = 0.638, 95%CI 0.461-0.883, p = 0.007), CHB (HR = 0.596, 95%CI 0.409-0.868, p = 0.007) or PCT (HR = 0.595, 95%CI 0.368-0.961, p = 0.034) than patients whose mutations were located after residues 117 (NoF2 subgroup). Patients in NoF1 subgroup still had lower age-related risks of CHB (HR = 0.652, 95%CI 0.476-0.893, p = 0.008) and PCT (HR = 0.605, 95%CI 0.398-0.918, p = 0.018) compared with those in combined NoF2 subgroup and other truncating mutation patients. NoF1 subgroup correspondingly had a longer estimated median lifespan (64 vs. 55 year, p = 0.037) than NoF2 subgroup. Among patients with missense mutations of VHL, only a small minority (23 of 286 missense mutations carriers) carried mutations involving neither HIF-α binding region nor elongin C binding region, who were grouped in MO subgroup. MO subgroup seemed to have a higher age-related risk of PHEO. In the whole cohort (n = 577), PHEO was an independent protective factor for CHB (p = 0.001) and survival (p = 0.005). RA and CHB failed to predict the age-related risk of each other. CONCLUSION: The mutation types and locations of VHL gene are associated with phenotypes. Genetic counselors could predict phenotypes more accurately based on more detailed genotype-phenotype correlations. Further genotype-phenotype studies should focus on the prediction of tumor recurrence, progression, and metastasis. The deep molecular mechanism of genotype-phenotype correlation is worth further exploring.

Construction and Validation of Novel Diagnostic and Prognostic DNA Methylation Signatures for Hepatocellular Carcinoma.

Hepatocellular carcinoma (HCC) is one of the most prevalent life-threatening human cancers and the leading cause of cancer-related mortality, with increased global incidence within the last decade. Identification of effective diagnostic and prognostic biomarkers would enable reliable risk stratification and efficient screening of high-risk patients, thereby facilitating clinical decision-making. Herein, we performed a comprehensive, robust DNA methylation analysis based on genome-wide DNA methylation profiling. We constructed a diagnostic signature with five DNA methylation markers, which precisely distinguished HCC patients from normal controls. Cox regression and LASSO analysis were applied to construct a prognostic signature with four DNA methylation markers. A one-to-one correlation analysis was carried out between genes of the whole genome and our prognostic signature. Exploration of the biological function and the role of the underlying significantly correlated genes was conducted. A mixed dataset of 463 HCC patients and 253 normal controls, derived from six independent datasets, was used to valid the diagnostic signature. Results showed a specificity of 96.84% and sensitivity of 96.77%. Class scores for the diagnostic signature were significantly different between normal controls, individuals with liver diseases, and HCC patients. The present signature has the potential to serve as a biomarker to monitor health in normal controls. Additionally, HCC patients were successfully separated into low-risk and high-risk groups by the prognostic signature, with a better prognosis for patients in the low-risk group. Kaplan-Meier and ROC analysis confirmed that the prognostic signature performed well. We found eight of the top ten genes to positively correlate with risk scores of the prognostic signature, and to be involved in cell cycle regulation. This eight-gene panel also served as a prognostic signature. The robust evidence presented in this study therefore demonstrates the effectiveness of the prognostic signature. In summary, we constructed diagnostic and prognostic signatures, which have potential for use in diagnosis, surveillance, and prognostic prediction for HCC patients. Eight genes that were significantly and positively correlated with the prognostic signature were strongly associated with cell cycle processes. Therefore, the prognostic signature can be used as a guide by which to measure responsiveness to cell-cycle-targeting agents.

Cytogenetic Spectrum of Ovotesticular Difference of Sex Development (OT DSD) among a Large Cohort of DSD Patients and Literature Review.

Ovotesticular difference of sex development (OT DSD) is a rare genetic disorder with an incidence of about 1/100,000 live births. The majority of OT DSD patients show a 46,XX karyotype, others may have 46,XX/46,XY chimerism or exhibit various mosaic sex chromosome combinations, and less commonly they may have a 46,XY karyotype. The aim of this work is to report the clinical, pathological, and karyotypic variations in OT DSD patients diagnosed among a large cohort of DSD patients. The study included 10 patients thoroughly evaluated for clinical, genital, and hormonal abnormalities and subjected to imaging studies, laparoscopy with gonadal biopsy, karyotype, and FISH analysis. The current study revealed a greater percentage of mosaic cell line combinations than previously reported and showed variable cytogenetic abnormalities, including the rare isodicentric (Y)(p11.32) abnormality and X;Y translocation. The study also revealed a unique pattern of gonadal type and combination frequencies. To our knowledge, this is the first study on OT DSD patients among a large cohort of DSD patients in Egypt and the Middle East.

Cistrome Partitioning Reveals Convergence of Somatic Mutations and Risk Variants on Master Transcription Regulators in Primary Prostate Tumors.

Thousands of noncoding somatic single-nucleotide variants (SNVs) of unknown function are reported in tumors. Partitioning the genome according to cistromes reveals the enrichment of somatic SNVs in prostate tumors as opposed to adjacent normal tissue cistromes of master transcription regulators, including AR, FOXA1, and HOXB13. This parallels enrichment of prostate cancer genetic predispositions over these transcription regulators' tumor cistromes, exemplified at the 8q24 locus harboring both risk variants and somatic SNVs in cis-regulatory elements upregulating MYC expression. However, Massively Parallel Reporter Assays reveal that few SNVs can alter the transactivation potential of individual cis-regulatory elements. Instead, similar to inherited risk variants, SNVs accumulate in cistromes of master transcription regulators required for prostate cancer development.

Shorter telomere length increases age-related tumor risks in von Hippel-Lindau disease patients.

Von Hippel-Lindau (VHL) disease is a rare autosomal dominant cancer syndrome caused by alterations of VHL gene. Patients are predisposed to develop pheochromocytomas and solid or cystic tumors of the central nervous system, kidney, pancreas, and retina. Remarkable phenotypic heterogeneity exits in organ involvement and tumor onset age between and within VHL families. However, no reliable markers have been found to predict the age-related tumor risks in VHL patients. A large Chinese cohort composed of 300 VHL patients and 92 healthy family controls was enrolled in our study. Blood relative telomere length was measured in 184 patients and all the controls available for genomic DNA samples. Age-related risks for the five major VHL-associated tumors were evaluated using Kaplan-Meier plots and Cox regression analysis. Differences in clinical phenotype were observed between Chinese cohort and the United Kingdom cohort. VHL patients showed significantly shorter telomere length than healthy family controls(P = 0.0183), and a positive correlation was found between telomere length and onset age of the five major tumors, respectively. Moreover, patients in the shorter telomere group (age-adjusted telomere length ≤ 0.44) suffered higher age-related risks for VHL-associated central nervous system hemangioblastomas (HR: 1.879, P = 0.004), renal cell carcinoma (HR: 2.126, P = 0.002) and pancreatic cyst and neuroendocrine tumors (HR: 2.093, P = 0.001). These results indicate that blood shorter telomere length is a new biomarker for age-related tumor risks in VHL patients, which will be crucial to genetic counseling and future research about the role of telomere shortening in the pathogenesis of VHL-associated tumors.

Gonadectomy in Complete Androgen Insensitivity Syndrome: Why and When?

Prophylactic gonadectomy has been recommended in complete androgen insensitivity syndrome (CAIS) because of an increased risk for the development of malignant germ cell tumors in the intra-abdominal gonads. No reliable screening parameters are available to detect early (pre-)malignant changes. Because the tumor risk before puberty is very low, the timing of gonadectomy has been postponed to allow spontaneous puberty and involvement of the patients in important decisions affecting their body and health. Gonadectomy after puberty is still discussed controversially. There are difficulties in determining the absolute malignancy risk for individuals with CAIS, difficulties with hormone therapy, and lack of studies supporting different protocols. In contrast, endogenous hormone profiles show very specific features that influence bone health, psychosocial well-being, and many other aspects which still have to be investigated. For women with CAIS who wish to keep their gonads, we propose a biannual screening program which has to be evaluated in a prospective multi-center trial.

Approach to the Diagnosis of Overgrowth Syndromes.

Overgrowth syndromes comprise a group of disorders associated with excessive growth and other features such as facial dysmorphism, developmental delay or intellectual disability, congenital anomalies, neurological problems and an increased risk of neoplasia. Recent advances in understanding the genetic basis of overgrowth syndromes has resulted in a move away from clinical classification to molecular classification of overgrowth syndromes. This review provides a structured clinical approach to patients with this group of disorders and includes most of the currently known overgrowth syndromes.

Reversible transformation and de-differentiation of human cells derived from induced pluripotent stem cell teratomas.

We first aimed to generate transformed cell lines from a human induced pluripotent stem cell (hiPSC)-teratoma, and then examined the tumorigenic risks of the differentiated cells from hiPSC explant, because hiPSC-derivatives give rise to tumors in immune-deficient mice when transplanted. The colonies isolated from sparse cultures of hiPSC-teratoma cells expressed NANOG and OCT3/4 strongly, and telomerase reverse transcriptase (TERT) weakly. However, soft agar assay demonstrated that only one of them generated colonies in the gel, though hiPSCs, hTERT-transfected immortal cells, and its oncogene-transfected cells did not form any colonies. Furthermore, none of colonies isolated from the soft agar gel on primary culture (passage 0) of teratoma cells, expressed NANOG and OCT3/4 in the expanded cultures. The second soft agar assay on the colony-derived cells was unexpectedly negative. The cumulative growth curve, telomere shortening, and senescence-associated ß-galactosidase (SA ß-gal) staining confirmed the mortality of these cells, suggesting their reversible transformation. By using medium for embryonic stem cell (ESC medium) after MCDB 131 (MCDB) medium, the differentiated culture cells derived from hiPSC-teratoma converted into the cells expressing undifferentiated marker proteins, which lost afterwords even in ESC medium with feeder SNL76/7. The reversibility of transformation and de-differentiation suggest that tumorigenic risks of differentiated cells arise when they are exposed to suitable niches in vivo. Thus, removal of only the undifferentiated cells from iPSC-derivatives before transplantation does not solve the problem. Elucidation of mechanisms of reversibility and control of epigenetic changes is discussed as a safety bottleneck for hiPSC therapy.