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.

MiR-129-5p exerts Wnt signaling-dependent tumor-suppressive functions in hepatocellular carcinoma by directly targeting hepatoma-derived growth factor HDGF.

BACKGROUND: In hepatocellular carcinoma (HCC), histone deacetylases (HDACs) are frequently overexpressed. This results in chromatin compaction and silencing of tumor-relevant genes and microRNAs. Modulation of microRNA expression is a potential treatment option for HCC. Therefore, we aimed to characterize the epigenetically regulated miR-129-5p regarding its functional effects and target genes to understand its relevance for HCC tumorigenesis. METHODS: Global miRNA expression of HCC cell lines (HLE, HLF, Huh7, HepG2, Hep3B) and normal liver cell lines (THLE-2, THLE-3) was analyzed after HDAC inhibition by miRNA sequencing. An in vivo xenograft mouse model and in vitro assays were used to investigate tumor-relevant functional effects following miR-129-5p transfection of HCC cells. To validate hepatoma-derived growth factor (HDGF) as a direct target gene of miR-129-5p, luciferase reporter assays were performed. Survival data and HDGF expression were analyzed in public HCC datasets. After siRNA-mediated knockdown of HDGF, its cancer-related functions were examined. RESULTS: HDAC inhibition induced the expression of miR-129-5p. Transfection of miR-129-5p increased the apoptosis of HCC cells, decreased proliferation, migration and ERK signaling in vitro and inhibited tumor growth in vivo. Direct binding of miR-129-5p to the 3'UTR of HDGF via a noncanonical binding site was validated by luciferase reporter assays. HDGF knockdown reduced cell viability and migration and increased apoptosis in Wnt-inactive HCC cells. These in vitro results were in line with the analysis of public HCC datasets showing that HDGF overexpression correlated with a worse survival prognosis, primarily in Wnt-inactive HCCs. CONCLUSIONS: This study provides detailed insights into the regulatory network of the tumor-suppressive, epigenetically regulated miR-129-5p in HCC. Our results reveal for the first time that the therapeutic application of mir-129-5p may have significant implications for the personalized treatment of patients with Wnt-inactive, advanced HCC by directly regulating HDGF. Therefore, miR-129-5p is a promising candidate for a microRNA replacement therapy to prevent HCC progression and tumor metastasis.

MicroRNA-449a Inhibits Triple Negative Breast Cancer by Disturbing DNA Repair and Chromatid Separation.

Chromosomal instability (CIN) can be a driver of tumorigenesis but is also a promising therapeutic target for cancer associated with poor prognosis such as triple negative breast cancer (TNBC). The treatment of TNBC cells with defects in DNA repair genes with poly(ADP-ribose) polymerase inhibitor (PARPi) massively increases CIN, resulting in apoptosis. Here, we identified a previously unknown role of microRNA-449a in CIN. The transfection of TNBC cell lines HCC38, HCC1937 and HCC1395 with microRNA-449a mimics led to induced apoptosis, reduced cell proliferation, and reduced expression of genes in homology directed repair (HDR) in microarray analyses. EME1 was identified as a new target gene by immunoprecipitation and luciferase assays. The reduced expression of EME1 led to an increased frequency of ultrafine bridges, 53BP1 foci, and micronuclei. The induced expression of microRNA-449a elevated CIN beyond tolerable levels and induced apoptosis in TNBC cell lines by two different mechanisms: (I) promoting chromatid mis-segregation by targeting endonuclease EME1 and (II) inhibiting HDR by downregulating key players of the HDR network such as E2F3, BIRC5, BRCA2 and RAD51. The ectopic expression of microRNA-449a enhanced the toxic effect of PARPi in cells with pathogenic germline BRCA1 variants. The newly identified role makes microRNA-449a an interesting therapeutic target for TNBC.

Ago-RIP Sequencing Identifies New MicroRNA-449a-5p Target Genes Increasing Sorafenib Efficacy in Hepatocellular Carcinoma.

BACKGROUND: Patients with hepatocellular carcinoma (HCC) have very limited treatment options. For the last fourteen years, the multi-tyrosine kinase inhibitor sorafenib has been used as standard-of-care therapeutic agent in advanced HCC. Unfortunately, drug resistance develops in many cases. Therefore, we aimed to find a way to mitigate drug resistance and to improve the sorafenib efficacy in HCC cells. MicroRNAs play a significant role in targeting genes involved in tumor control suggesting microRNA/sorafenib combination therapy as a promising treatment option in advanced HCC. METHODS: MiR-449a-5p target genes were identified by Ago-RIP sequencing and validated by luciferase reporter assays and expression analyses. Target gene expression and survival data were analyzed in public HCC datasets. Tumor-relevant functional effects of miR-449a-5p and its target genes as well as their impact on the effects of sorafenib were analyzed using in vitro assays. An indirect transwell co-culture system was used to survey anti-angiogenic effects of miR-449a-5p. RESULTS: PEA15, PPP1CA and TUFT1 were identified as direct target genes of miR-449a-5p. Overexpression of these genes correlated with a poor outcome of HCC patients. Transfection with miR-449a-5p and repression of miR-449a-5p target genes inhibited cell proliferation and angiogenesis, induced apoptosis and reduced AKT and ERK signaling in HLE and Huh7 cells. Importantly, miR-449a-5p potentiated the efficacy of sorafenib in HCC cells via downregulation of PEA15, PPP1CA and TUFT1. CONCLUSIONS: This study provides detailed insights into the targetome and regulatory network of miR-449a-5p. Our results demonstrate for the first time that targeting PEA15, PPP1CA and TUFT1 via miR-449a overexpression could have significant implications in counteracting sorafenib resistance suggesting miR-449a-5p as a promising candidate for a microRNA/sorafenib combination therapy.

Classification of fluorescent R-Band metaphase chromosomes using a convolutional neural network is precise and fast in generating karyograms of hematologic neoplastic cells.

Karyotype analysis has a great impact on the diagnosis, treatment and prognosis in hematologic neoplasms. The identification and characterization of chromosomes is a challenging process and needs experienced personal. Artificial intelligence provides novel support tools. However, their safe and reliable application in diagnostics needs to be evaluated. Here, we present a novel laboratory approach to identify chromosomes in cancer cells using a convolutional neural network (CNN). The CNN identified the correct chromosome class for 98.8% of chromosomes, which led to a time saving of 42% for the karyotyping workflow. These results demonstrate that the CNN has potential application value in chromosome classification of hematologic neoplasms. This study contributes to the development of an automatic karyotyping platform.

MicroRNA-192-5p inhibits migration of triple negative breast cancer cells and directly regulates Rho GTPase activating protein 19.

Among the different breast cancer subtypes, triple-negative breast cancer (TNBC) is associated with a poor prognosis, low survival rates, and high expression of histone deacetylases. Treatment with histone deacetylase inhibitor trichostatin A (TSA) leads to an increased expression of potential tumor-suppressive miRNAs. Characterization of these miRNAs can help to find new molecular targets for treatment of TNBC. We identified differentially expressed miRNAs by microarray analyses after treatment with TSA in the TNBC cell lines HCC38, HCC1395, and HCC1935. The gene locus of hsa-miRNA-192-5p (miR-192) and hsa-miR-194-2 (miR-194-2) with its host gene, long noncoding RNA miR-194-2HG, has been linked to inhibition of migration in different tumor types. Therefore, we examined tumor-relevant functional effects using WST-1-based proliferation, capsase-3/7-based apoptosis, and trans-well migration assays after transfection with miRNA mimics or specific siRNAs. We demonstrated the tumor-suppressive capacity of miR-192 in TNBC cells, which was exerted through inhibition of proliferation, induction of apoptosis, and reduction of migration. Gene expression and bioinformatics analyses of TNBC cell lines transfected with miR-192 mimics, identified a number of genes involved in migration including the Rho GTPase Activating Protein ARHGAP19. Through RNA immunoprecipitation we demonstrated the direct binding of miR-192 and ARHGAP19. Downregulation of ARHGAP19 expression by either miR-192 or siRNA inhibited migration of TNBC cells significantly. Our findings demonstrate that overexpression of epigenetically deregulated miR-192 decreases proliferation, promotes apoptosis, and inhibits migration of TNBC cell lines.

Students' attitudes towards somatic genome editing versus genome editing of the germline using an example of familial leukemia.

Although the discussion on possibilities and pitfalls of genome editing is ever present, limited qualitative data on the attitudes of students, who will come into contact with this technology within a social and professional context, is available. The attitude of 97 medical students and 103 students of other subjects from Hannover and Oldenburg, Germany, was analyzed in winter 2017/18. For this purpose, two dilemmas on somatic and germline genome editing concerning familial leukemia were developed. After reading the dilemmas, the students filled out a paper-and-pencil test with five open questions. The qualitative evaluation of the answers was carried by a deductive-inductive procedure of content analysis. There was a high approval for the use of somatic genome editing. When it came to germline genome editing, concerns were raised regarding enhancement, interventions in nature, and loss of uniqueness. The students recognized that somatic genome editing and germline genome editing prove different ethical challenges and need to be judged separately. Many students expressed not feeling fully informed. The results of this project show the importance of educating the public about the possibilities, limitations, and risks of somatic and germline genome editing. We recommend that this should already be addressed in schools in order to optimally prepare students and adults for participation in public discourse. Especially for patients affected by genetic diseases, it is of great importance that the treating physicians and geneticists are sufficiently informed about the method of genome editing to ensure good counseling.

Psychological Distress and Coping Ability of Women at High Risk of Hereditary Breast and Ovarian Cancer before Undergoing Genetic Counseling-An Exploratory Study from Germany.

Carriers of pathogenic variants causing hereditary breast and ovarian cancer (HBOC) are confronted with a high risk to develop malignancies early in life. The present study aimed to determine the type of psychological distress and coping ability in women with a suspicion of HBOC. In particular, we were interested if the self-assessed genetic risk had an influence on health concerns and coping ability. Using a questionnaire established by the German HBOC Consortium, we investigated 255 women with breast cancer and 161 healthy women before they were seen for genetic counseling. The group of healthy women was divided into groups of high and low self-assessed risk. In our study, healthy women with a high self-assessed risk stated the highest stress level and worries about their health and future. A quarter of the women requested psychological support. Overall, only few women (4-11%) stated that they did not feel able to cope with the genetic test result. More women (11-23%, highest values in the low-risk group) worried about the coping ability of relatives. The results of our exploratory study demonstrate that the women, who presented at the Department of Human Genetics, Hanover Medical School, Germany were aware of their genetic risk and had severe concerns about their future health, but still felt able to cope with the genetic test result.

MTF1 binds to metal-responsive element e within the ATP7B promoter and is a strong candidate in regulating the ATP7B expression.

Wilson's disease is an autosomal recessive disorder resulting from copper excess. Some patients with clinical Wilson's disease symptoms exhibit no or only heterozygous pathogenic variants in the coding region of the disease-causing ATP7B gene. Therefore, the ATP7B promoter region is of special interest. Metal-responsive elements (MREs) located in the ATP7B promoter are promising motifs in modulating the ATP7B expression. We studied protein interaction of MREe, MREc, and MREd by electrophoretic mobility shift assays and revealed specific interactions for all MREs. We further narrowed down the specific binding site. Proteins potentially binding to the three MREs were identified by MatInspector analyses. Metal regulatory transcription factor 1 (MTF1) could be validated to bind to MREe by electrophoretic mobility shift assays. ATP7B promoter-driven reporter gene expression was significantly increased because of this interaction. MTF1 is a strong candidate in regulating the ATP7B expression through MREe binding.

Wnt status-dependent oncogenic role of BCL9 and BCL9L in hepatocellular carcinoma.

BACKGROUND: Activation of Wnt/ß-catenin pathway is a frequent event in hepatocellular carcinoma and is associated with enhanced cell survival and proliferation. Therefore, targeting this signaling pathway is discussed as an attractive therapeutic approach for HCC treatment. BCL9 and BCL9L, two homologous coactivators of the ß-catenin transcription factor complex, have not yet been comprehensively characterized in HCC. We aimed to elucidate the roles of BCL9 and BCL9L, especially regarding Wnt/ß-catenin signaling and their prognostic value in HCC. METHODS: Expression of BCL9/BCL9L was determined in HCC cell lines (HLE, HLF, Huh7, HepG2, Hep3B, and Huh6) and normal liver cell lines (THLE-2 and THLE-3). To analyze proliferation and apoptosis, BCL9 and/or BCL9L were knocked down in Wnt-inactive HLE and Wnt-active HepG2 and Huh6 cells using siRNA. Subsequently, Wnt reporter assays were performed in HepG2 and Huh6 cells. BCL9 and BCL9L expression, clinicopathological and survival data of public HCC datasets were analyzed, taking the Wnt signaling status into account. RESULTS: Knockdown of BCL9L, but not of BCL9, reduced Wnt signaling activity. Knockdown of BCL9 and/or BCL9L reduced cell viability and increased apoptosis of Wnt-inactive HCC cells, but had no effect in Wnt-active cells. Expression of BCL9 and BCL9L was upregulated in human HCC and increased with progressing dedifferentiation. For BCL9L, higher expression was observed in tumors of larger size. Overexpression of BCL9 and BCL9L correlated with poor overall survival, especially in HCC without activated Wnt signaling. CONCLUSION: Oncogenic BCL9 proteins represent promising targets for cancer therapy and inhibiting them may be particularly beneficial in Wnt-inactive HCCs.

The microRNA-449 family inhibits TGF-ß-mediated liver cancer cell migration by targeting SOX4.

BACKGROUND & AIMS: Modulation of microRNA expression is a potential treatment for hepatocellular carcinoma (HCC). Therefore, the epigenetically regulated microRNA-449 family (miR-449a, miR-449b, miR-449c) was characterized with regards to its functional effects and target genes in HCC. METHODS: After transfection of miR-449a, miR-449b, and/or miR-449c, tumor-relevant functional effects were analyzed using in vitro assays and a xenograft mouse model. Binding specificities, target genes, and regulated pathways of each miRNA were identified by microarray analyses. Target genes were validated by luciferase reporter assays and expression analyses in vitro. Furthermore, target gene expression was analyzed in 61 primary human HCCs compared to normal liver tissue. RESULTS: Tumor suppressive effects, binding specificities, target genes, and regulated pathways of miR-449a and miR-449b differed from those of miR-449c. Transfection of miR-449a, miR-449b, and/or miR-449c inhibited cell proliferation and migration, induced apoptosis, and reduced tumor growth to different extents. Importantly, miR-449a, miR-449b, and, to a lesser degree, miR-449c directly targeted SOX4, which codes for a transcription factor involved in epithelial-mesenchymal transition and HCC metastasis, and thereby inhibited TGF-ß-mediated cell migration. CONCLUSIONS: This study provides detailed insights into the regulatory network of the epigenetically regulated miRNA-449 family and, for the first time, describes distinct tumor suppressive effects and target specificities of miR-449a, miR-449b, and miR-449c. Our results indicate that particularly miR-449a and miR-449b may be considered for miRNA replacement therapy to prevent HCC progression and metastasis. LAY SUMMARY: In this study, we demonstrated that the microRNA-449 family acts as a tumor suppressor in liver cancer by causing cell death and inhibiting cell migration. These effects are caused by downregulation of the oncogene SOX4, which is frequently overexpressed in liver cancer. We conclude that the microRNA-449 family may be a target for liver cancer therapy.

Establishing a murine xenograft-model for long-term analysis of factors inducing chromosomal instability in myelodysplastic syndrome: Pitfalls and successes.

Myelodysplastic syndromes (MDS) are difficult to culture long-term showing the need of a model to study the fate of cells with MDS-abnormalities associated with chromosomal instability (CIN). This approach to establish a xenograft model transplanting human hematopoietic stem cells (HSC) with different independent lentivirally-mediated MDS-related modifications into immunodeficient mice is a long-lasting and tedious experiment with many parameters and every positive as well as non-functioning intermediate step will help the research community. As the establishment of appropriate xenograft models is increasing worldwide we aim to share our experiences to contribute toward minimizing loss of mice and following the "right" approach. Here, modified HSCs were intrafemorally transplanted into NSG and/or NSGS mice: (1) RPS14-haploinsufficiency, (2) TP53-deficiency, (3) TP53 hotspot mutations (R248W, R175H, R273H, R249S). Engraftment was achieved and cytogenetic analyses showed human cells with normal karyotypes. However, in all experiments with NSG mice, mainly control cells or GFP-negative cells were engrafted, not allowing observation of modified HSCs. In NSGS mice, engraftment rate was higher, but mice developed graft-versus-host disease. In summary, engraftment of HSCs is promising and could be used to analyze the induction of CIN. However, the analysis of modified HSCs is limited and further experiments are required to improve this model.

Induction of Chromosomal Instability via Telomere Dysfunction and Epigenetic Alterations in Myeloid Neoplasia.

Chromosomal instability (CIN) is a characteristic feature of cancer. In this review, we concentrate on mechanisms leading to CIN in myeloid neoplasia, i.e., myelodysplastic syndrome (MDS) or acute myeloid leukemia (AML). The pathogenesis of myeloid neoplasia is complex and involves genetic and epigenetic alterations. Chromosome aberrations define specific subgroups and guide clinical decisions. Genomic instability may play an essential role in leukemogenesis by promoting the accumulation of genetic lesions responsible for clonal evolution. Indeed, disease progression is often driven by clonal evolution into complex karyotypes. Earlier studies have shown an association between telomere shortening and advanced MDS and underlined the important role of dysfunctional telomeres in the development of genetic instability and cancer. Several studies link chromosome rearrangements and aberrant DNA and histone methylation. Genes implicated in epigenetic control, like DNMT3A, ASXL1, EZH2 and TET2, have been discovered to be mutated in MDS. Moreover, gene-specific hypermethylation correlates highly significantly with the risk score according to the International Prognostic Scoring System. In AML, methylation profiling also revealed clustering dependent on the genetic status. Clearly, genetic instability and clonal evolution are driving forces for leukemic transformation. Understanding the mechanisms inducing CIN will be important for prevention and for novel approaches towards therapeutic interventions.

Histone methyltransferase Suv39h1 deficiency prevents Myc-induced chromosomal instability in murine myeloid leukemias.

Suv39h1 mediates heterochromatin formation in pericentric and telomeric regions by trimethylation of lysine 9 of histone 3 (H3K9me3). Yet, its role in the induction of chromosomal instability is poorly understood. We established a leukemia model by retrovirally expressing Myc in wild-type and histone methyltransferase Suv39h1-deficient hematopoietic cells and characterized the resulting leukemias for chromosomal instability. All mice that received cells overexpressing Myc developed myeloid leukemia with a median survival of 44 days posttransplantation. Myc-overexpressing wild-type leukemias demonstrated clones with numerical chromosomal aberrations (5/16). In secondary transplantations of these leukemic cells, structural changes, mostly end-to-end fusions of chromosomes, appeared (10/12). In contrast, leukemic cells overexpressing Myc with reduced or no Suv39h1 expression had a normal karyotype in primary, secondary, and tertiary transplantations (16/16). Myc-transduced Suv39h1-deficient cells showed less critically short telomeres (P < 0.05) compared with Myc-transduced wild-type bone marrow cells. Gene expression analysis showed upregulation of genes involved in the alternative lengthening of telomeres (ALT) mechanism. Thus, we hypothesize that loss of Suv39h1 implies activation of the ALT mechanism, in turn ensuring telomere length and stability. Our data show for the first time that Suv39h1 deficiency may prevent chromosomal instability by more efficient telomere stabilization in hematopoietic bone marrow cells overexpressing Myc.