Copy Number Deletions Research Articles

Clinical relevance of BCOR internal tandem duplication and TP53 aberration in clear cell sarcoma of the kidney.

Clear cell sarcoma of the kidney (CCSK) is the second most common pediatric renal malignancy, characterized by BCOR internal tandem duplication (ITD), YWHAE rearrangement, BCOR-CCNB3 fusion, and lack of other consistent structural alteration. We accidentally identified TP53 deletion in CCSK, which was often associated with adverse clinical outcomes. In this study, we assessed the incidence as well as the clinical relevance of these molecules in CCSK patients. BCOR ITD, YWHAE rearrangement, BCOR-CCNB3 fusion and TP53 status were examined by polymerase chain reaction, fluorescence in situ hybridization, or Sanger sequencing in a cohort of 39 patients with CCSK. Among them, 34 cases (87.18%) had BCOR ITD, 1 (2.56%) had YWHAE rearrangement, and 1 (2.56%) had BCOR-CCNB3 gene fusion. The remaining 3 (7.69%) harbored none of these aberrations. BCOR ITD, YWHAE rearrangement and BCOR-CCNB3 were mutually exclusive. Furthermore, 25.64% of the cohort acquired TP53 aberration (10/39, 3 with both copy number deletion and point mutation, 6 with deletion only, and 1 with mutation only), all of which were associated with BCOR ITD. Patients with or without BCOR ITD or TP53 aberration did not differ in demographic characteristics such as sex, onset age, or tumor stage at diagnosis. However, the overall survival rates and progression-free survival rates of BCOR ITD or TP53 deletion groups showed obvious downward trends, albeit not all reaching statistical significance. Patients with both BCOR ITD and TP53 deletion had the poorest prognosis.

Abstract P5-02-16: SPEN is a biomarker for CDK4/6 inhibitor resistance in patients with metastatic hormone receptor positive (HR+)/HER2- breast cancer

Abstract Background: Despite significant improvements in the treatment of breast cancer (BC), metastatic disease remains the principal cause of BC-related death. Through analysis of rapid autopsy collected biospecimens, we have previously identified Split Ends (SPEN) alterations in patients with metastatic HR+/HER2- BC (Savas et al. 2016). The role of SPEN in BC is poorly defined. Here we aimed to further explore the function of this gene in metastatic HR+/HER2- metastatic BC (mBC). Methods: We explored the clinical and genomic characteristics of SPEN altered mBC in human sequencing datasets. We created a model of SPEN loss using a gene knockdown (KD) via siRNA in MCF7 cells. Flow cytometry and western blot analysis was utilized to investigate the molecular impact of SPEN loss. The KD and non-targeting control cells were then subjected to a high throughput kinase inhibitor screen (n=480 compounds) to identify sensitive and resistant therapeutics. Finally, we used an in-house metastatic HR+/HER2- BC patient cohort treated with CDK (cyclin-dependent kinase) 4/6 inhibitors to validate SPEN loss as a marker of resistance. Results: Using a cohort of 7519 BC samples, SPEN alterations (mutation and copy number deletions) were found to be significantly enriched in HR+ mBC vs primary HR+ disease (29% vs 7%, respectively p< 0.0001). SPEN altered compared with SPEN wild type (WT) HR+ mBCs were significantly associated with higher tumor mutational burden (median 4.6 vs 1.7, p < 0.0001), more large-scale transitions (median 20 vs 14, p= 0.006), increased fraction of genome altered (52% vs 35%, p< 0.0001), and enrichment of APOBEC-induced mutations (65% vs 42%, p=0.004) respectively. Taken together, these results suggest greater genomic instability in patients with tumors with SPEN loss compared with WT. This hypothesis was further supported when SPEN KD cells showed significantly increased growth rate (p= 0.04), and significantly greater DNA damage by γH2Ax staining (p=0.03) compared with control cells. In a kinase inhibitor compound screen, SPEN KD cells displayed significant resistance to the CDK4/6 inhibitor palbociclib (p< 0.0001) compared with WT cells. We validated this finding in vitro by demonstrating SPEN KD cell resistance to other CDK4/6 inhibitors ribociclib and abemaciclib (p= 0.02 and 0.0004 respectively). In our in-house cohort of 56 patients with HR+ mBC treated with CDK4/6 inhibitors, we found that the HR+ mBC patients with a SPEN alteration have significantly decreased overall survival (OS) compared with WT patients, (median OS 34 months vs not reached, respectively; HR 3.18, 95%CI 0.94-10.73, p=0.049). Conclusion: These results provide the first clinical evidence that SPEN alterations are enriched in HR+ mBC. Additionally, SPEN may be a biomarker for CDK4/6 inhibitor resistance in this subtype. These results warrant further analysis into the role of SPEN in BC and its relevance in clinical management. Reference: Savas P, Teo ZL, Lefevre C, et al. The subclonal architecture of metastatic breast cancer: Results from a prospective community-based rapid autopsy program "cascade". PLoS medicine 2016;13:e1002204. Citation Format: Courtney T. van Geelen, Zhi Ling Teo, Peter Savas, Stephen J. Luen, Kylie A. Clarke, Sneha Sant, Karla J. Cowley, Franco Caramia, Kaylene J. Simpson, Fabrice Andre, Sarah-Jane Dawson, Richard Pearson, Sherene Loi. SPEN is a biomarker for CDK4/6 inhibitor resistance in patients with metastatic hormone receptor positive (HR+)/HER2- breast cancer [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P5-02-16.

Candidate targets of copy number deletion events across 17 cancer types.

Genome variation is the direct cause of cancer and driver of its clonal evolution. While the impact of many point mutations can be evaluated through their modification of individual genomic elements, even a single copy number aberration (CNA) may encompass hundreds of genes and therefore pose challenges to untangle potentially complex functional effects. However, consistent, recurring and disease-specific patterns in the genome-wide CNA landscape imply that particular CNA may promote cancer-type-specific characteristics. Discerning essential cancer-promoting alterations from the inherent co-dependency in CNA would improve the understanding of mechanisms of CNA and provide new insights into cancer biology and potential therapeutic targets. Here we implement a model using segmental breakpoints to discover non-random gene coverage by copy number deletion (CND). With a diverse set of cancer types from multiple resources, this model identified common and cancer-type-specific oncogenes and tumor suppressor genes as well as cancer-promoting functional pathways. Confirmed by differential expression analysis of data from corresponding cancer types, the results show that for most cancer types, despite dissimilarity of their CND landscapes, similar canonical pathways are affected. In 25 analyses of 17 cancer types, we have identified 19 to 169 significant genes by copy deletion, including RB1, PTEN and CDKN2A as the most significantly deleted genes among all cancer types. We have also shown a shared dependence on core pathways for cancer progression in different cancers as well as cancer type separation by genome-wide significance scores. While this work provides a reference for gene specific significance in many cancers, it chiefly contributes a general framework to derive genome-wide significance and molecular insights in CND profiles with a potential for the analysis of rare cancer types as well as non-coding regions.

Detection of somatic copy number deletion of the CDKN2A gene by quantitative multiplex PCR for clinical practice.

A feasible method to detect somatic copy number deletion (SCND) of genes is still absent to date. Interstitial base-resolution deletion/fusion coordinates for CDKN2A were extracted from published articles and our whole genome sequencing (WGS) datasets. The copy number of the CDKN2A gene was measured with a quantitative multiplex PCR assay P16-Light and confirmed with whole genome sequencing (WGS). Estimated common deletion regions (CDRs) were observed in many tumor suppressor genes, such as ATM, CDKN2A, FAT1, miR31HG, PTEN, and RB1, in the SNP array-based COSMIC datasets. A 5.1 kb base-resolution CDR could be identified in >90% of cancer samples with CDKN2A deletion by sequencing. The CDKN2A CDR covers exon-2, which is essential for P16INK4A and P14ARF synthesis. Using the true CDKN2A CDR as a PCR target, a quantitative multiplex PCR assay P16-Light was programmed to detect CDKN2A gene copy number. P16-Light was further confirmed with WGS as the gold standard among cancer tissue samples from 139 patients. The 5.1 kb CDKN2A CDR was found in >90% of cancers containing CDKN2A deletion. The CDKN2A CDR was used as a potential target for developing the P16-Light assay to detect CDKN2A SCND and amplification for routine clinical practices.

Comprehensive analysis of the correlation between GSTM1 and tumor immunity in colon cancer

Glutathione S-transferase mu 1 (GSTM1) is one of the major glutathione conjugation enzymes. Its expression and activity have been suggested to correlate with the occurrence of colon cancer; however, the role of GSTM1 in tumor immunity remains unclear. Relevant data downloaded from The Cancer Genome Atlas (TCGA), Clinical Proteomic Tumor Analysis Consortium (CPTAC), and Human Protein Atlas (HPA) was used to perform a multi-dimensional expression analysis of GSTM1 in colon adenocarcinoma (COAD). The correlation between GSTM1 and tumor immunity was analyzed with multiple online tools. Then protein-protein interaction (PPI) network and functional enrichment analyses of GSTM1-associated immunomodulators were performed. Further, we developed the Cox regression model based on the GSTM1-related immunomodulators. Finally, a GSTM1-based clinical nomogram and a calibration curve was established to predict the probability and accuracy of long-term survival. GSTM1 was significantly downregulated in COAD versus normal tissues. Infiltration levels of B cells, CD8+ T cells, and dendritic cells were closely correlated to GSTM1 gene copy number deletion, and GSTM1 expression levels in COAD positively correlated with dendritic cell, B cell, neutrophil, and macrophage infiltration. Functional enrichment analysis indicated 36 GSTM1-related immunomodulators are involved in immune-related pathways of regulating T cell activation and lymphocytic activation. A 2-gene prognostic risk signature based on the 36 GSTM1-related immunomodulators was built using the Cox regression model, and the risk signature in combination with stage had an area under the curve (AUC) value of 0.747 by the receiver operating characteristic method. patients with higher risk scores-calculated based on 2 gene prognostic risk characteristics and further identified as an independent prognostic factor-were associated with worse survival using the Kaplan-Meier analysis. Together, the clinical nomogram and calibration curve based on GSTM1 suggested a good prediction accuracy for long-term survival probability. Our study provided evidence supporting the significant role of GSTM1 in COAD immunity and suggests GSTM1 as a potential novel target for COAD immunotherapy.

Genomic characterization of intracranial teratomas using whole genome sequencing.

Intracranial teratoma is a rare neoplasm of the central nervous system, often classified into mature and immature types and occurs mainly in children and adolescents. To date, there has been no comprehensive genomic characterization analysis of teratoma due to its rarity of the cases. Forty-six patients with intracranial teratomas were collected and 22 of them underwent whole-exome sequencing, including 8 mature teratomas and 14 immature teratomas. A comprehensive analysis was performed to analyze somatic mutations, copy number variants (CNVs), mutational signatures, and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway in our cohort. The most common somatic mutated gene in intracranial teratomas was CARD11 (18%) and IRS1 (18%), followed by PSMD11, RELN, RRAS2, SMC1A, SYNE1 and ZFHX3, with mutation rates of 14% for the latter six genes. Copy number variation was dominated by amplification, among which ARAF (50%), ATP2B3 (41%), GATA1 (41%), ATP6AP1 (36%), CCND2 (36%) and ZMYM3 (36%) were the most frequently amplified genes. Copy number deletion of SETDB2 and IL2 only appeared in immature teratoma (43% and 36%, respectively), but not in mature teratoma (p = 0.051 and 0.115, respectively). Prognostic analysis showed that TP53 mutations might be associated with poor prognosis of intracranial teratomas patients. Our study revealed the genetic characteristics of intracranial teratoma which might be valuable for guiding future targeted therapies.

A novel cuproptosis-related gene signature of prognosis and immune microenvironment in head and neck squamous cell carcinoma cancer.

Cuproptosis is a novel form of cell death that is highly related to mitochondrial metabolism and mediated by protein lipoacetylation. This study systematically assessed the differential expression and genetic alterations of cuproptosis-related genes (CRGs) in head and neck squamous-cell carcinoma (HNSCC) and constructed CRG risk models to predict survival in patients with HNSCC. We investigated the expression of 19 CRGs in HNSCC and noncancerous tissues, and the relationship between mutation load, immune infiltration, and clinical features was examined based on data from public databases. CRG risk models were constructed by univariate Cox analysis and lasso regression and validated by independent datasets for their accuracy in predicting survival outcomes in patients with HNSCC. The expression distribution of CRGs in HNSCC cells was further explored in the HNSCC single-cell sequencing dataset. NFE2L2, ATP7A, FDX1, LIAS, DLD, DLAT, PDHB, MTF1 and DBT were highly expressed in noncancerous samples, while GLS, CDKN2A and DLST were highly expressed in HNSCC samples (p < 0.05). Gene copy number variation frequency (CNV) revealed CDKN2A, FDX1 and DLAT copy number deletions and LIPT2 and NFE2L2 copy number increases. Ten CRGs were used to construct a risk model to predict overall survival (OS) in HNSCC, yielding reduced OS in the high-risk group compared to the low-risk group, training group (p = 9.733e - 05), and testing group (p = 0.040). The CRG risk model was significantly correlated with various immune cells, regulatory T cells (Tregs) and memory B cells were significantly negatively correlated (p = 0.027, p = 0.00084), and resting CD4 memory T cells was significantly positively correlated (p = 9e - 04). Most CRGs significantly affected the clinical characteristics of HNSCC. NFE2L2, SLC31A1, PDHA1, CDKN2A and DBT were highly expressed in epithelial cells of HNSCC, while SLC31A1, DBT and NFE2L2 were highly expressed in T cells, and SLC31A1 in B cells. In monocytes, NFE2L2, SLC31A1 and PDHA1 were highly expressed. The CRG risk model can be used as a potential prognostic factor for HNSCC patients and may provide new insights into cancer treatment from the perspective of copper metabolism.

Duplication Versus Deletion Through the Lens of 15q13.3: Clinical and Research Implications of Studying Copy Number Variants Associated with Neuropsychiatric Disorders in Induced Pluripotent Stem Cell-Derived Neurons.

Copy number variants (CNVs), involving duplication or deletion of susceptible intervals of the human genome, underlie a range of neurodevelopmental and neuropsychiatric disorders. As accessible in vivo animal models of these disorders often cannot be generated, induced pluripotent stem cell (iPSC) models derived from patients carrying these CNVs can reveal alterations of brain development and neuronal function that contribute to these disorders. CNVs involving deletion versus duplication of a particular genomic interval often result both in distinct clinical phenotypes and in differential phenotypic penetrance. This review initially focuses on CNVs at 15q13.3, which contribute to autism spectrum disorder, attention deficit/hyperactivity disorder, and schizophrenia. Like most CNVs, deletions at 15q13.3 usually cause severe clinical phenotypes, while duplications instead result in highly variable penetrance, with some carriers exhibiting no clinical phenotype. Here, we describe cellular and molecular phenotypes seen in iPSC-derived neuronal models of 15q13.3 duplication and deletion, which may contribute both to the differential clinical consequences and phenotypic penetrance. We then relate this work to many other CNVs involving both duplication and deletion, summarizing findings from iPSC studies and their relationship to clinical phenotype. Together, this work highlights how CNVs involving duplication versus deletion can differentially alter neural development and function to contribute to neuropsychiatric disorders. iPSC-derived neuronal models of these disorders can be used both to understand the underlying neurodevelopmental alterations and to develop pharmacological or molecular approaches for phenotypic rescue that may suggest leads for patient intervention. Top: Deletion versus duplication of the same genomic interval results in different clinical phenotypes and degrees of phenotypic penetrance. Example findings schematized. Bottom: iPSC-derived neurons from individuals with these CNVs involving deletion versus duplication likewise often differential phenotypes (increases or decreases) in the categories shown. Figure created with BioRender.com.

The Profile and Clinical Significance of ITGB2 Expression in Non-Small-Cell Lung Cancer.

Integrins are involved in extracellular and intracellular signaling and are often aberrantly expressed in tumors. Integrin beta 2 (ITGB2) has previously been demonstrated to be correlated with the host defense. However, the expression profile and role of ITGB2 in non-small-cell lung cancer (NSCLC) remain unclear. Here, we found that the genetic alterations in ITGB2 was predominated by gene mutation and copy number deletion using cBioPortal analysis, and its expression was downregulated in the NSCLC tissues, as validated by the UALCAN, TCGA, and GEO databases and our tissue samples. Kaplan-Meier (KM) plotter analysis revealed that patients with a lower ITGB2 expression had a shorter overall survival (OS) time (p = 0.01). Moreover, 1089 differentially expressed genes (DEGs) in the NSCLC tissues were screened using the TCGA database. The GO and KEGG enrichment analysis showed that the DEGs were closely associated with immune processes and cell adhesion. The protein-protein interaction (PPI) network revealed that 10 of 15 EMT-related genes among the DEGs might lead to the metastasis of NSCLC. Concomitantly, the expression of ITGB2 was positively correlated with the infiltration of Treg cells and Myeloid-derived suppressor cells (MDSC). Biologically, the ectopic expression of ITGB2 significantly inhibited the proliferation and metastasis of NSCLC cells. Mechanistically, we demonstrated that ITGB2 suppressed the expression of N-cadherin, Vimentin, Slug, Snail, and Twist, while it promoted E-cadherin expression, according to gain-of-function studies. In conclusion, ITGB2 can inhibit the proliferation and migration of NSCLC cells, leading to a poor prognosis, via epithelial-mesenchymal transition (EMT) signaling.

Remdesivir does not affect mitochondrial DNA copy number or deletion mutation frequency in aged male rats: A short report.

Remdesivir is a leading therapy in patients with moderate to severe coronavirus 2 (SARS-CoV-2) infection; the majority of whom are older individuals. Remdesivir is a nucleoside analog that incorporates into nascent viral RNA, inhibiting RNA-directed RNA polymerases, including that of SARS-CoV-2. Less is known about remdesivir’s effects on mitochondria, particularly in older adults where mitochondria are known to be dysfunctional. Furthermore, its effect on age-induced mitochondrial mutations and copy number has not been previously studied. We hypothesized that remdesivir adversely affects mtDNA copy number and deletion mutation frequency in aged rodents. To test this hypothesis, 30-month-old male F333BNF1 rats were treated with remdesivir for three months. To determine if remdesivir adversely affects mtDNA, we measured copy number and mtDNA deletion frequency in rat hearts, kidneys, and skeletal muscles using digital PCR. We found no effects from three months of remdesivir treatment on mtDNA copy number or deletion mutation frequency in 33-month-old rats. These data support the notion that remdesivir does not compromise mtDNA quality or quantity at old age in mammals. Future work should focus on examining additional tissues such as brain and liver, and extend testing to human clinical samples.

NGS-Based Molecular Karyotyping of Multiple Myeloma: Results from the GEM12 Clinical Trial.

Simple SummaryMultiple Myeloma (MM) is considered an incurable chronic disease, which prognosis depends on the presence of different genomic alterations. To accomplish a complete molecular diagnosis in a single essay, we have designed and validated a capture-based NGS approach to reliably identify pathogenic mutations (SNVs and indels), genomic alterations (CNVs and chromosomic translocations), and IGH rearrangements. We have observed a good correlation of the results obtained using our capture panel with data obtained by both FISH and WES techniques. In this study, the molecular classification performed using our approach was significantly associated with the stratification and outcome of MM patients. Additionally, this panel has been proven to detect specific IGH rearrangements that could be used as biomarkers in patient follow-ups through minimal residual disease (MRD) assays. In conclusion, we think that MM patients could benefit from the use of this capture-based NGS approach with a more accurate, single-essay molecular diagnosis.Next-generation sequencing (NGS) has greatly improved our ability to detect the genomic aberrations occurring in multiple myeloma (MM); however, its transfer to routine clinical labs and its validation in clinical trials remains to be established. We designed a capture-based NGS targeted panel to identify, in a single assay, known genetic alterations for the prognostic stratification of MM. The NGS panel was designed for the simultaneous study of single nucleotide and copy number variations, insertions and deletions, chromosomal translocations and V(D)J rearrangements. The panel was validated using a cohort of 149 MM patients enrolled in the GEM2012MENOS65 clinical trial. The results showed great global accuracy, with positive and negative predictive values close to 90% when compared with available data from fluorescence in situ hybridization and whole-exome sequencing. While the treatments used in the clinical trial showed high efficacy, patients defined as high-risk by the panel had shorter progression-free survival (p = 0.0015). As expected, the mutational status of TP53 was significant in predicting patient outcomes (p = 0.021). The NGS panel also efficiently detected clonal IGH rearrangements in 81% of patients. In conclusion, molecular karyotyping using a targeted NGS panel can identify relevant prognostic chromosomal abnormalities and translocations for the clinical management of MM patients.

Comprehensive Analysis of the Immune Implication of AKAP12 in Stomach Adenocarcinoma.

A kinase anchor protein 12 (AKAP12) as a tumor suppressor in various cancers has been extensively studied and confirmed. However, its immune implication in stomach adenocarcinoma (STAD) remains uncertain. Here, using The Cancer Genome Atlas (TCGA), Human Protein Atlas (HPA), Tumor Immune Estimation Resource (TIMER), Cancer Cell Line Encyclopedia (CCLE), integrated repository portal for tumor-immune system interactions (TISIDB), and Search Tool for the Retrieval of Interaction Gene/Proteins (STRING) database, we systematically analyzed the immune correlation of AKAP12 from three aspects including immune infiltration cells, immune-related pathways, and immunomodulators and developed a AKAP12-related 4-gene signature for prognosis prediction. Our results showed that AKAP12 mRNA and protein levels were downregulated in STAD patients, and its expression was positively related to CD4+ T cells and macrophages. In addition, the immune cell infiltration levels were associated with AKAP12 gene copy number deletion in STAD. Based on CCLE database, we found that AKAP12 coexpressed genes were enriched in several immune- and cancer-related pathways, which was further validated by Gene Set Enrichment Analysis (GSEA). Moreover, we identified 46 immunomodulators that were significantly related to AKAP12 expression using TISIDB database, and these immunomodulators were involved in immune-related pathways including Th17 cell differentiation and natural killer cell-mediated cytotoxicity. Additionally, based on the 46 AKAP12-related immunomodulators, a 4-gene risk prediction signature was developed using the Cox regression model. The risk signature was identified as an independent prognostic factor, which can accurately predict the prognosis of patients with STAD, showing good predictive performance. Furthermore, we constructed a prognostic nomogram and calibration to predict and assess patient survival probabilities by integrating the risk score and other clinical factors. In conclusion, our study provides strong evidence that AKAP12 is closely related to tumor immunity in STAD from three aspects: immune infiltration cells, immune pathways, and immunomodulators. More importantly, the AKAP12-related prognostic signature may have a good application prospect for clinical practice.

Gene signatures, immune infiltration, and drug sensitivity based on a comprehensive analysis of m6a RNA methylation regulators in cervical cancer

BackgroundCervical cancer is the fourth most common cancer in women. N6-dimethyladenosine (m6A) mRNA methylation is closely associated with cervical cancer.MethodsUsing TCGA database, we studied the expression and mutation of m6A-related genes in cervical squamous cell carcinoma and endocervical adenocarcinoma (CESC) and obtained genetic characteristics based on an m6A risk model and prognostic value of m6A. We studied the effects of the m6A risk score on immune features and genomic changes of patients with CESC, evaluated the sensitivity of patients with CESC to different small-molecule drugs based on the m6A risk score, and established a clinical prediction model.ResultsTen m6A-related genes were differentially expressed between CESC and normal tissues. High-risk patients had a low overall survival (OS) and significantly low immune scores but showed no significantly altered stromal scores. The tumor mutation burden (TMB) and tumor neoantigen levels significantly differed between the high- and low-risk groups. In the high-risk group, copy number variation (CNV) changes mainly led to gene amplification, while in the low-risk group, CNV changes primarily manifested as gene copy number deletions. ZC3H13 expression was low in CESC tissues. ZC3H13 knockdown promoted CESC cell proliferation, migration, and invasion, reducing the RNA methylation levels. Rapamycin suppressed the CESC cell proliferation, migration, and invasion abilities, increasing the m6A levels.Conclusionm6A mRNA methylation is closely related to the occurrence, development, immune invasion, drug sensitivity, and prognosis of cervical cancer. The prognostic m6A feature model of m6A signature genes can accurately predict the OS of patients with CESC. Drugs targeting factors regulating m6A mRNA methylation might offer a good prospect for treating cervical cancer.

108P Copy loss enrichment at metastatic disease progression in hormone receptor-positive (HR+)/HER2-negative metastatic breast cancer patients treated with endocrine therapy and CDK4/6 inhibition

Blood copy number burden (bCNB), derived from a low-pass whole genome sequencing assay (PredicineCNBTM) is a comprehensive measure of copy number variation (CNV), including amplifications and deletions across the entire genome. We previously reported that increasing bCNB levels in blood samples collected from HR+/HER2-negative metastatic breast cancer patients at baseline and during treatment with endocrine therapy and CDK4/6 inhibition (ET + CDK4/6i) preceded radiographic detection of disease progression.

Novel Insights into the Etiology, Genetics, and Embryology of Hypoplastic Left Heart Syndrome.

Hypoplastic left heart syndrome (HLHS) is a relatively rare severe congenital heart defect (CHD) closely linked to other left ventricular outflow tract (LVOT) lesions including bicuspid aortic valve (BAV), one of the most common heart defects. While HLHS, BAV, and other LVOT lesions have a strong genetic underpinning, their genetic etiology remains poorly understood. Findings from a large-scale mouse mutagenesis screen showed HLHS has a multigenic etiology and is genetically heterogenous, explaining difficulties in identifying the genetic causes of HLHS. In Ohia mice, HLHS shows incomplete penetrance. Some mice exhibited small LV with normal aorta, and others a normal LV with hypoplastic aorta, indicating the LV hypoplasia is not hemodynamically driven. In Ohia mutants, HLHS was found to have a digenic modular construction, with mutation in a chromatin modifier causing the small LV phenotype and mutation in Pcdha9 causing the aorta/aortic valve hypoplasia. The Pcdha9 mutation alone can cause BAV, and in the human genome two common deletion copy number variants spanning PCDHA7-10 are associated with BAV. Hence the digenic etiology of HLHS can account for the close association of HLHS, a rare CHD, with BAV, one of the most common CHD. Functional analysis of Ohia HLHS heart tissue showed severe mitochondrial dysfunction in the small LV, while the normal size RV is also affected but milder, suggesting possible role in vulnerability of surgically palliated HLHS patients to heart failure. These findings suggest insights into the genetics of HLHS may yield new therapies for improving outcome for patients with HLHS.

Maternal Xp22.31 copy-number variations detected in non-invasive prenatal screening effectively guide the prenatal diagnosis of X-linked ichthyosis.

Background and aims: X-linked ichthyosis (XLI) is a common recessive genetic disease caused by the deletion of steroid sulfatase (STS) in Xp22.31. Maternal copy-number deletions in Xp22.31 (covering STS) can be considered an incidental benefit of genome-wide cell-free DNA profiling. Here, we explored the accuracy and clinical value of maternal deletions in Xp22.31 during non-invasive prenatal screening (NIPS). Materials and methods: We evaluated 13,156 pregnant women who completed NIPS. The maternal deletions in Xp22.31 revealed by NIPS were confirmed with maternal white blood cells by chromosome microarray analysis (CMA) or copy-number variation sequencing (CNV-seq). Suspected positive women pregnant with male fetuses were informed and provided with prenatal genetic counseling. Results: Nineteen maternal deletions in Xp22.31 covering STS were detected by NIPS, which were all confirmed, ranging in size from 0.61 to 1.77 Mb. Among them, eleven women with deletions in male fetuses accepted prenatal diagnoses, and finally nine cases of XLI were diagnosed. The nine XLI males had differing degrees of skin abnormalities, and of them, some male members of ten families had symptoms associated with XLI. Conclusion: NIPS has the potential to detect clinically significant maternal X chromosomal CNVs causing XLI, which can guide the prenatal diagnosis of X-linked ichthyosis and reflect the family history, so as to enhance pregnancy management as well as children and family members’ health management.

Identification of immune-related ferroptosis prognostic marker and in-depth bioinformatics exploration of multi-omics mechanisms in thyroid cancer.

Background: Factors such as variations in thyroid carcinoma (THCA) gene characteristics could influence the clinical outcome. Ferroptosis and immunity have been verified to play an essential role in various cancers, and could affect the cancer patients’ prognosis. However, their relationship to the progression and prognosis of many types of THCA remains unclear. Methods: First, we extracted prognosis-related immune-related genes and ferroptosis-related genes from 2 databases for co-expression analysis to obtain prognosis-related differentially expressed immune-related ferroptosis genes (PR-DE-IRFeGs), and screened BID and CDKN2A for building a prognostic model. Subsequently, multiple validation methods were used to test the model’s performance and compare its performance with other 4 external models. Then, we explored the mechanism of immunity and ferroptosis in the occurrence, development and prognosis of THCA from the perspectives of anti-tumor immunity, CDKN2A-related competitive endogenous RNA regulatory, copy number variations and high frequency gene mutation. Finally, we evaluated this model’s clinical practice value. Results: BID and CDKN2A were identified as prognostic risk and protective factors, respectively. External data and qRT-PCR experiment also validated their differential expression. The model’s excellent performance has been repeatedly verified and outperformed other models. Risk scores were significantly associated with most immune cells/functions. Risk score/2 PR-DE-IRFeGs expression was strongly associated with BRAF/NRAS/HRAS mutation. Single copy number deletion of CDKN2A is associated with upregulation of CDKN2A expression and worse prognosis. The predicted regulatory network consisting of CYTOR, hsa-miRNA-873-5p and CDKN2A was shown to significantly affect prognosis. The model and corresponding nomogram have been shown to have excellent clinical practice value. Conclusion: The model can effectively predict the THCA patients’ prognosis and guide clinical treatment. Ferroptosis and immunity may be involved in the THCA’s progression through antitumor immunity and BRAF/NRAS/HRAS mutation. CYTOR-hsa-miRNA-873-5p-CDKN2A regulatory networks and single copy number deletion of CDKN2A may also affect THCA′ progression and prognosis.

New insights into the pathogenesis and molecular understanding of cutaneous T-cell lymphomas

The pathogenesis of cutaneous T‑cell lymphomas (CTCL) is still an enigma. Therefore, extensive translational research efforts have been undertaken in recent years to gain further clinical and molecular insights. There is increasing evidence that the different clinical appearance of the CTCL subtypes derives from the assumption that they develop from different skin subpopulations of Tcells. Detection and quantification of the malignant T‑cell clones is crucial for the diagnosis and prognosis of CTCL. Numerous recurrent mutant cellular signalling pathways have been found in recent years. This includes the JAK-STAT, NFκB, T‑cell receptor and MAP kinase signalling pathways, as well as cell cycle control and epigenetics. The most recent analyses imply atumour evolution model with initial copy number variation, like amplification or deletions of specific DNA fragments (CNVs) and only subsequent later single nucleotide variations (SNVs). The crucial question, however, is which CNVs are sufficient to initiate general tumourigenesis? The challenge is to identify possible driver genes. Increasing molecular understanding in CTCL will include new breakthrough therapeutic options in the near future.

Molecular classification of endometrial cancers using an integrative DNA sequencing panel (271)

<b>Objectives:</b> The Cancer Genome Atlas (TCGA) has identified four molecular subgroups of endometrial cancers (EC) with distinct differences in prognosis and response to adjuvant treatment. Stratification of patients according to molecular profiles is critical for individualized therapy at diagnosis, but adoption of molecular classification into clinical practice remains challenging due to the complexity and costs associated with sequencing. We aimed to develop a simple and affordable molecular technique to classify EC into four TCGA subgroups using our high-depth targeted sequencing panel. <b>Methods:</b> Women with newly diagnosed EC were prospectively recruited from three cancer centers in Ontario, Canada, between 2015 and 2018. Tumors were reflexively assessed for mismatch repair (MMR) protein expression by immunohistochemistry (IHC). Using our custom-designed panel, 181 formalin-fixed paraffin-embedded (FFPE) EC samples were sequenced. Our panel was able to identify somatic mutations, copy number variants, insertions and deletions, copy neutral loss of heterozygosity, structural rearrangements, and promoter methylation from a single aliquot of DNA. Variants were analyzed for pathogenicity, and clinical-pathologic information was collected through medical records. <b>Results:</b> Of 181, 86 (48%) were classified into microsatellite instability-high/hypermutated cohort (MSI-h or MMRd), of which 62 (72%) harbored <i>MLH1</i> promoter methylation, and 24 (27%) had pathogenic variants in MMR genes. Concordance with clinical IHC and methylation testing results was high at 99%. Of cases with a single classifier, three (1.6%; <i>n</i>=181) had pathogenic <i>POLE</i> exonuclease domain mutation (<i>POLE</i>mut), 15 (8%) had a pathogenic p53 variant (p53mut), and 61 (34%) had no specific molecular profile subtype (NSMP). Sixteen (9%; <i>n</i>=181) had more than one molecular classifying feature, with eight (4%) having MMRd-p53mut, six (3%) with MMRd-<i>POLE</i>mut, one (0.5%) with MMRd-<i>POLE</i>mut-p53mut, and one (0.5%) with <i>POLE</i>mut-p53mut. Overall, there were 11 (6%) with <i>POLE</i> mutations (three single and nine multiple classifiers). Survival outcomes of MMRd, <i>POLEmut,</i> p53mut, and NSMP groups stratified similarly to TCGA data, but when the MMRd group was further subclassified according to the mechanism of MMR loss, the MLH1 promoter methylated group did worse than those with somatic MMR pathogenic variants (5-year OS: 0.72 [0.57-0.92] vs 1.00 [1.00-1.00]; p=0.013 and RFS: 0.70 [0.58-0.85] vs 0.92 [0.82-1.00]; p=0.032). In contrast, those with somatic MMR pathogenic variants had similar outcomes to the <i>POLE</i>mut subtype (p=0.396) (Figure 1). <b>Conclusions:</b> Our NGS panel can classify EC into four TCGA subgroups through a simplified process and can be implemented reflexively in clinical practice. The higher rate of multiple classifiers (9%) in this study warrants further investigation. The difference in survival between MLH1 methylated group within MMRd cohort suggests that further subclassification may be required for accurate prognostication.

A novel mutation of X-linked recessive deafness gene POU3F4 in a boy with congenital deafness.

PurposeTo report an interstitial deletion of Xq21.1 in chromosome X in a boy with congenital deafness.MethodsThe proband underwent a thorough physical examination and a detailed audiological and temporal bone computed tomography (CT) scan. Cochlear implantation was performed on the proband, and follow‐up was conducted. High throughput sequencing and copy number analysis was made of peripheral blood samples from the proband, family members, and control subjects.ResultsSensorineural hearing loss was present in the boy and temporal bone CT scan showed a bilateral incomplete partition type III anomaly (IP‐III). Q21.1 (79.40–83.32 Mb) of chromosome X in the proband had a copy number deletion with a fragment size of about 3.92 Mb. Categories of auditory performance scores and SIR scores of the cochlea in this child improved after surgery.ConclusionThrough the analysis of POU3F4, a novel mutation site with potentially pathogenic significance was found.Level of Evidence: 5.