1p Deletions Research Articles

Event-free survival in neuroblastoma with MYCN amplification and deletion of 1p or 11q may be associated with altered immune status

BackgroundNeuroblastoma exhibits substantial heterogeneity, which is intricately linked to various genetic alterations. We aimed to explore immune status in the peripheral blood and prognosis of patients with neuroblastoma with different genetic characteristics.MethodsWe enrolled 31 patients with neuroblastoma and collected samples to detect three genetic characteristics. Peripheral blood samples were tested for immune cells and cytokines by fluorescent microspheres conjugated with antibodies and flow cytometry. Event-free survival (EFS) was analyzed using the Kaplan‒Meier method.ResultsTwenty-two patients had genetic aberrations, including MYCN amplification in 6 patients, chromosome 1p deletion in 9 patients, and chromosome 11q deletion in 14 patients. Two genetic alterations were present in seven patients. The EFS was worse in patients with MYCN amplification or 1p deletion than in the corresponding group, whereas 11q deletion was a prognostic factor only in patients with unamplified MYCN. Changes in immune status revealed a decrease in the proportion of T cells in blood, and an increase in regulatory T cells and immunosuppression-related cytokines such as interleukin (IL)-10. The EFS of the IL-10 high-level group was lower than that of the low-level group. Patients with concomitant genetic alterations and a high level of IL-10 had worse EFS than other patients.ConclusionsPatients with neuroblastoma characterized by these genetic characteristics often have suppressed T cell response and an overabundance of immunosuppressive cells and cytokines in the peripheral blood. This imbalance is significantly associated with poor EFS. Moreover, if these patients show an elevated levels of immunosuppressive cytokines such as IL-10, the prognosis will be worse.

Higher tumor mutational burden is associated with inferior outcomes among pediatric patients with neuroblastoma.

Neuroblastoma is a pediatric malignancy with heterogeneous clinical outcomes. Our aim was to identify prognostic genetic markers for patients with neuroblastoma, who were treated with the Taiwan Pediatric Oncology Group (TPOG) neuroblastoma N2002 protocol, to improve risk stratification and inform treatment. Our analysis was based on 53 primary neuroblastoma specimens, diagnosed pre-chemotherapy, and 11 paired tumor relapse specimens. Deep sequencing of 113 target genes was performed using a custom panel. Multiplex ligation-dependent probe amplification was performed to identify clinical outcomes related to copy-number variations. We identified 128 variations associated with survival, with the number of variations being higher in the relapse than that in the diagnostic specimen (p=.03). The risk of event and mortality was higher among patients with a tumor mutational burden ≥10 than that in patients with a lower burden (p<.0001). Multivariate analysis identified tumor mutational burden, MYCN amplification, and chromosome 3p deletion as significant prognostic factors, independent of age at diagnosis, sex, and tumor stage. The 5-year event-free survival and overall survival rate was lower among patients with high tumor burden than in patients with low tumor burden. Furthermore, there was no survival of patients with an ALK F1147L variation at 5 years after diagnosis. Genome sequencing to determine the tumor mutational burden and ALK variations can improve the risk classification of neuroblastoma and inform treatment.

Mitoferrin2 is a synthetic lethal target for chromosome 8p deleted cancers

BackgroundSomatic copy number alterations are a hallmark of cancer that offer unique opportunities for therapeutic exploitation. Here, we focused on the identification of specific vulnerabilities for tumors harboring chromosome 8p deletions.MethodsWe developed and applied an integrative analysis of The Cancer Genome Atlas (TCGA), the Cancer Dependency Map (DepMap), and the Cancer Cell Line Encyclopedia to identify chromosome 8p-specific vulnerabilities. We employ orthogonal gene targeting strategies, both in vitro and in vivo, including short hairpin RNA-mediated gene knockdown and CRISPR/Cas9-mediated gene knockout to validate vulnerabilities.ResultsWe identified SLC25A28 (also known as MFRN2), as a specific vulnerability for tumors harboring chromosome 8p deletions. We demonstrate that vulnerability towards MFRN2 loss is dictated by the expression of its paralog, SLC25A37 (also known as MFRN1), which resides on chromosome 8p. In line with their function as mitochondrial iron transporters, MFRN1/2 paralog protein deficiency profoundly impaired mitochondrial respiration, induced global depletion of iron-sulfur cluster proteins, and resulted in DNA-damage and cell death. MFRN2 depletion in MFRN1-deficient tumors led to impaired growth and even tumor eradication in preclinical mouse xenograft experiments, highlighting its therapeutic potential.ConclusionsOur data reveal MFRN2 as a therapeutic target of chromosome 8p deleted cancers and nominate MFNR1 as the complimentary biomarker for MFRN2-directed therapies.

The role of systemic therapy in advanced skull base chordomas: overview of the current state and the MD Anderson protocol.

The role of systemic therapy in primary or advanced and metastatic chordoma has been traditionally limited because of the inherent resistance to cytotoxic therapies and lack of specific or effective therapeutic targets. Despite resection and adjuvant radiation therapy, local recurrence rates in clival chordoma remain high and the risk of systemic metastases is not trivial, leading to significant morbidity and mortality. Recently, molecular targeted therapies (MTTs) and immune checkpoint inhibitors (ICIs) have emerged as promising therapeutic avenues in chordoma. In recent years, preclinical studies have identified potential targets based on intrinsic genetic dependencies, epigenetic modulators, or newly identified tumor-associated cell populations driving treatment resistance and recurrence. Nonetheless, the role of systemic therapies in the neoadjuvant or adjuvant setting for primary, locally progressive, and distant metastatic chordomas is still being investigated. Herein, an overview of current and emerging systemic treatment strategies in advanced clival chordoma is provided. Furthermore, several molecular biomarkers have been recently uncovered as potential predictors of the response to specific molecular therapeutics. The authors describe the recently discovered role of 1p36 and 9p21 deletions as biomarkers capable of guiding drug selection. Then they discuss completed and ongoing clinical trials of MTTs, including several tyrosine kinase inhibitors used as monotherapy or in combination, such as imatinib, sorafenib, dasatinib, and lapatinib, among others, as well as mammalian target of rapamycin inhibitors such as everolimus and rapamycin. They present their experience and other recent studies demonstrating vast benefits in advanced chordoma from ICIs. Additionally, they provide a brief overview of novel systemic strategies such as adoptive cell transfer (CAR-T and NK cells), oncolytic viruses, epigenetic targeting (KDM6, HDAC, and EZH2 inhibitors), and several promising preclinical studies with high translational potential. Finally, the authors present their institutional multidisciplinary protocol for the incorporation of systemic therapy for both newly diagnosed and recurrent chordomas based on molecular studies including upfront enrollment in MTT trials in patients with epidermal growth factor receptor upregulation or INI-1 deficiency or enrollment in ICI clinical trials for patients with high tumor mutational burden or high PD-L1 expression on tumor cells or in the tumor microenvironment.

TRIM33 loss in multiple myeloma is associated with genomic instability and sensitivity to PARP inhibitors

Deletions of chromosome 1p (del(1p)) are a recurrent genomic aberration associated with poor outcome in Multiple myeloma (MM.) TRIM33, an E3 ligase and transcriptional co-repressor, is located within a commonly deleted region at 1p13.2. TRIM33 is reported to play a role in the regulation of mitosis and PARP-dependent DNA damage response (DDR), both of which are important for maintenance of genome stability. Here, we demonstrate that MM patients with loss of TRIM33 exhibit increased chromosomal instability and poor outcome. Through knockdown studies, we show that TRIM33 loss induces a DDR defect, leading to accumulation of DNA double strand breaks (DSBs) and slower DNA repair kinetics, along with reduced efficiency of non-homologous end joining (NHEJ). Furthermore, TRIM33 loss results in dysregulated ubiquitination of ALC1, an important regulator of response to PARP inhibition. We show that TRIM33 knockdown sensitizes MM cells to the PARP inhibitor Olaparib, and this is synergistic with the standard of care therapy bortezomib, even in co-culture with bone marrow stromal cells (BMSCs). These findings suggest that TRIM33 loss contributes to the pathogenesis of high-risk MM and that this may be therapeutically exploited through the use of PARP inhibitors.

Grade 3 Meningiomas Following 2021 WHO Guidelines—A Dual Center Retrospective Study on Clinical Characteristics and Outcomes

INTRODUCTION: In their updated 2021 guidelines, the World Health Organization (WHO) for the first time included molecular markers in the classification of Grade 3 meningiomas (G3Ms). Now, homozygous deletion of CDKN2A/B or TERT Promoter (TERTp) mutations independently qualify a meningioma as Grade 3 [1]. METHODS: We performed a dual-center retrospective review from 2005 to 2021 on primary G3Ms. To adhere to guidelines, tumors were regraded when RNA sequencing, methylation profiling, or DNA microarray was available. Tumor recurrence was the outcome metric. RESULTS: A total of 1358 patients were reviewed with 31 (2.3%) primary tumors meeting criteria for Grade 3 and 4/31 (13%) meeting only molecular criteria. Among the 31 patients, 16 (52%) were female with a median age of 65. Upon regrading, 25 (81%) met only histological criteria, 3 (9.7%) had only TERTp mutations, 1 (3.1%) had only CDKN2A deletion, 1 (3.1%) met histological criteria and had TERT mutation, and 1 (3.1%) met histological criteria and had CDKN2A deletion. Molecular profiling of 18 G3Ms demonstrated chromosomal deletions in 1p (16/18, 89%), 14q (10/18, 56%), and 22q (16/18, 89%). Common locations were frontal (11/31, 35%) and parietal convexity (6/31, 23%). Histological findings included necrosis (24/31, 77%), hypercellularity (23/31, 74%), and prominent nucleoli (21/31, 68%). Tumors recurred in 9/31 (29%) and 8/31 (26%) recurred multiple times. CONCLUSIONS: Here we present the first description of G3Ms following the updated 2021 WHO guidelines.

Abstract 1257: CHD5 suppresses glioblastoma by inhibiting MYC

Abstract Fundamentally, cancer is a disease caused by genetic and epigenetic alterations that converge to reprogram gene expression networks, leading to unrestrained proliferation. Glioblastoma (GBM) is the most prevalent and aggressive primary brain cancer, median survival being approximately one year and the 5-year survival rate being only 5%. Despite decades of effort, this devastating picture has not appreciably improved and effective therapies have been elusive for GBM patients. A better understanding of GBM biology is essential for developing more effective therapies. Although several genetic alterations have been implicated in gliomagenesis, driving genetic factors responsible for GBM are still obscure, and the interplay between genetic alterations and epigenetic dysregulation is largely undocumented during the gliomagenic process. Here, we show that CHD5 — a gene mapping to the 1p36 chromosomal region that is notoriously deleted in many cancers, is recurrently deleted in over 20% of GBM cases and is further downregulated through epigenetic means. To delineate how CHD5 loss promotes gliomagenesis, we established a glioma-prone mouse model harboring conditional alleles of Pten, Trp53, and Chd5. We developed an engineered mouse neural stem cell (NSCs)-based strategy to elicit glioma formation, as NSCs are the major cell-of-origin for GBM. We show that Chd5 loss significantly impairs NSCs differentiation while promoting proliferation, transformation, and gliomagenesis in vivo. Mechanistically, Chd5 forms a Chd3-containing but Chd4-independent NuRD complex that directly binds the Myc promoter and super enhancers to govern Myc expression in normal NSCs, with the Snf2 domain of Chd5 playing the most critical chromatin regulating role in the context of GBM. Chd5 loss triggers the remodeling of chromatin, enhances accessibility, and augments Myc expression, leading to the formation of highly aggressive glioma. Furthermore, reactivating CHD5 in human GBM xenograft models significantly extends survival. This work demonstrates the tumor suppressive role of CHD5 in gliomagenesis, providing therapeutic insights for cancers with 1p36 deletions. In parallel, this work presents a powerful strategy for rapidly interrogating gene function during gliomagenesis using engineering NSCs, and the generation of novel mouse models with classic clinical features of GBM, offering new approaches for elucidating GBM biology that can inform on therapeutic opportunities for treating patients with GBM. Citation Format: Xueqin Sherine Sun, Alea Mills. CHD5 suppresses glioblastoma by inhibiting MYC [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 1257.

Analysis of genetic etiology in a patient with 1p36 deletion syndrome in conjunct with Snijders Blok-Campeau syndrome

To explore the genetic basis for a patient with unexplained developmental delay and special facial features. A male patient admitted to the Maternal and Child Health Care Hospital of Gansu Province on May 27, 2021 due to infertility was selected as the study subject. Clinical data of the patient was collected, and genomic DNA was extracted from peripheral blood samples from the patient and his parents. Whole exome sequencing (WES) was carried out, and candidate variant was verified by Sanger sequencing. The patient was found to harbor a 2.54 Mb deletion in 1p36.33p36.32 and a heterozygous c.1123G>C (p.E375Q) variant of the CHD3 gene, neither of which was detected in his parents. The patient was diagnosed with Snijders Blok-Campeau syndrome in conjunct with 1p36 deletion syndrome, which has enabled genetic counseling for his family.

Abstract B014: CHD5 suppresses glioblastoma by inhibiting MYC

Abstract Fundamentally, cancer is a disease caused by genetic and epigenetic alterations that converge to reprogram gene expression networks, leading to unrestrained proliferation. Glioblastoma (GBM) is the most prevalent and aggressive primary brain cancer, median survival being approximately one year and the 5-year survival rate being only 5%. Despite decades of effort, this devastating picture has not appreciably improved and effective therapies have been elusive for GBM patients. A better understanding of GBM biology is essential for developing more effective therapies. Although several genetic alterations have been implicated in gliomagenesis, driving genetic factors responsible for GBM are still obscure, and the interplay between genetic alterations and epigenetic dysregulation is largely undocumented during the gliomagenic process. Here, we show that CHD5 — a gene mapping to the 1p36 chromosomal region that is notoriously deleted in many cancers, is recurrently deleted in over 20% of GBM cases and is further downregulated through epigenetic means. To delineate how CHD5 loss promotes gliomagenesis, we established a glioma-prone mouse model harboring conditional alleles of Pten, Trp53, and Chd5. We developed an engineered mouse neural stem cell (NSCs)-based strategy to elicit glioma formation, as NSCs are the major cell-of-origin for GBM. We show that Chd5 loss significantly impairs NSCs differentiation while promoting proliferation, transformation, and gliomagenesis in vivo. Mechanistically, Chd5 forms a Chd3-containing but Chd4-independent NuRD complex that directly binds the Myc promoter and super enhancers to govern Myc expression in normal NSCs, with the Snf2 domain of Chd5 playing the most critical chromatin regulating role in the context of GBM. Chd5 loss triggers the remodeling of chromatin, enhances accessibility, and augments Myc expression, leading to the formation of highly aggressive glioma. Furthermore, reactivating CHD5 in human GBM xenograft models significantly extends survival. This work demonstrates the tumor suppressive role of CHD5 in gliomagenesis, providing therapeutic insights for cancers with 1p36 deletions. In parallel, this work presents a powerful strategy for rapidly interrogating gene function during gliomagenesis using engineering NSCs and highlights the generation of novel mouse models with classic clinical features of GBM, offering new approaches for elucidating GBM biology that can inform on therapeutic opportunities for treating patients with GBM. Citation Format: Xueqin Sherine Sun, Alea Mills. CHD5 suppresses glioblastoma by inhibiting MYC [abstract]. In: Proceedings of the AACR Special Conference on Brain Cancer; 2023 Oct 19-22; Minneapolis, Minnesota. Philadelphia (PA): AACR; Cancer Res 2024;84(5 Suppl_1):Abstract nr B014.

Association of Solitary Tumors in Polycythemia Vera with 3p Deletion

Association of Solitary Tumors in Polycythemia Vera with 3p Deletion

17q Gain in Neuroblastoma: A Review of Clinical and Biological Implications.

Neuroblastoma (NB) is the most frequent extracranial solid childhood tumor. Despite advances in the understanding and treatment of this disease, the prognosis in cases of high-risk NB is still poor. 17q gain has been shown to be the most frequent genomic alteration in NB. However, the significance of this remains unclear because of its high frequency and association with other genetic modifications, particularly segmental chromosomal aberrations, 1p and 11q deletions, and MYCN amplification, all of which are also associated with a poor clinical prognosis. This work reviewed the evidence on the clinical and biological significance of 17q gain. It strongly supports the significance of 17q gain in the development of NB and its importance as a clinically relevant marker. However, it is crucial to distinguish between whole and partial chromosome 17q gains. The most important breakpoints appear to be at 17q12 and 17q21. The former distinguishes between whole and partial chromosome 17q gain; the latter is a site of IGF2BP1 and NME1 genes that appear to be the main oncogenes responsible for the functional effects of 17q gain.

Human Genetics of Tricuspid Atresia and Univentricular Heart.

Tricuspid atresia (TA) is a rare congenital heart condition that presents with a complete absence of the right atrioventricular valve. Because of the rarity of familial and/or isolated cases of TA, little is known about the potential genetic abnormalities contributing to this condition. Potential responsible chromosomal abnormalities were identified in exploratory studies and include deletions in 22q11, 4q31, 8p23, and 3p as well as trisomies 13 and 18. In parallel, potential culprit genes include the ZFPM2, HEY2, NFATC1, NKX2-5, MYH6, and KLF13 genes. The aim of this chapter is to expose the genetic components that are potentially involved in the pathogenesis of TA in humans. The large variability in phenotypes and genotypes among cases of TA suggests a genetic network that involves many components yet to be unraveled.

Clinicopathological and molecular genetic characteristics of ELOC mutated renal cell carcinoma

Objective: To investigate the clinicopathological features, molecular genetic features, differential diagnosis and prognosis of ELOC mutated renal cell carcinoma. Methods: From January 2015 to June 2022, 11 cases of renal cell carcinoma with clear-cell morphology, expression of CAⅨ and CK7 and no 3p deletion were collected. Two cases of ELOC mutant renal cell carcinoma were diagnosed using whole exome sequencing (WES). The clinical features, morphology, immunophenotype, FISH and WES results were analyzed. The relevant literature was reviewed. Results: The two patients were both male, aged 29 and 51 years, respectively. They were both found to have a renal mass by physical examination. The maximum diameters of the tumors were 3.5 cm and 2.0 cm, respectively. At the low magnification, the tumors were well-defined. The tumor cells showed a pushing border and were separated by thick fibrous bands, forming nodules. The tumor cells were arranged in a variety of patterns, including tubular, papillary, solid nest or alveolar. At high magnification, the tumor cells were large, with well-defined cell borders and clear cytoplasm or fine eosinophilic granules. CAⅨ was diffusely box-like positive in both cases. Case 1 was partially and moderately positive for CK7, strongly positive for CD10, diffusely and moderately positive for P504S, and weakly positive for 34βE12. In case 2, CK7 and CD10 were both partially, moderately positive and P504s were diffusely positive, but 34βE12 was negative. FISH results showed that both cases had no 3p deletion. ELOC c.235T>A (p.Y79N) mutation was identified using WES in case 1, while ELOC c.236_237inv (p.Y79C) mutation was identified in case 2. Conclusions: As a new clinical entity, ELOC mutated renal cell carcinoma may be underdiagnosed due to its overlap with clear cell renal cell carcinoma in morphology and immunophenotype. The diagnosis of renal cell carcinoma with ELOC mutation should be confirmed by morphology, immunohistochemistry, FISH and gene mutation detection. However, more additional cases are needed to explain its biological behavior and prognosis.

High-resolution PGT-A results in incidental identification of patients with small pathogenic copy number variants

PurposeThis study aimed to evaluate whether a high-throughput high-resolution PGT-A method can detect copy number variants (CNVs) that could have clinical implications for patients and their embryos.MethodsA prospective analysis of PGT-A cases was conducted using a high-resolution SNP microarray platform with over 820,000 probes. Cases where multiple embryos possessed the same segmental imbalance were identified, and preliminary PGT-A reports were issued recommending either parental microarray or conventional karyotyping to identify CNVs or translocations.ResultsAnalysis of 6080 sequential PGT-A cases led to identification of 41 cases in which incidental findings were observed (0.7%) and parental testing was recommended. All cases, in which parental studies were completed, confirmed the original PGT-A incidental findings. In 2 of the cases, parental studies indicated a pathogenic variant with clinical implications for the associated embryos. In one of these cases, the patient was identified as a carrier of a duplication in chromosome 15q11.2:q11.2 (SNRPN + +), which is associated with autism spectrum disorder. In the second case, the patient was heterozygous positive for an interstitial deletion of 3p26.1:p26.3, which is associated with 3p deletion syndrome and had clinical implications for the patient and associated embryos. In each case, parental studies were concordant with PGT-A findings and revealed the presence of an otherwise unknown CNV.ConclusionHigh-throughput high-resolution SNP array–based PGT-A has the ability to detect previously unknown and clinically significant parental deletions, duplications, and translocations. The use of cost-effective SNP array–based PGT-A methods may improve the effectiveness of PGT by identifying and preventing previously unknown pathogenic CNVs in children born to patients seeking in vitro fertilization.

Deletion in 1p36.33-p36.32 is associated with pancytopenia: a case report

Background1P36 deletion syndrome is recognized as the most common terminal microdeletion syndrome in humans, characterized by early developmental delay and consequent intellectual disability, seizure disorder, and distinctive facial features. Variable deletion locations may attributed to phenotypic variability. However, the abnormal phenotypes of hematology are rarely reported in 1P36 deletion syndrome patients.Case presentationWe present a case of postnatal intellectual disability accompanied by pancytopenia. Copy number variation analysis revealed a pathogenic deletion in 1p36.331p36.32 with a deletion size of 2.21 Mb. Following successful treatment with glucocorticoids, the patient was diagnosed with immuno-related hemocytopenia (IRH).DiscussionThe patient experienced IRH, an uncommon characteristic of 1p36 deletion syndrome. The deletion fragment of 1p36.33-p36.32, particularly the loss of GNB1 gene, has been associated with the development of pancytopenia. Genotype-phenotype correlations are valuable in identifying the genes responsible for various clinical characteristics of the syndrome by associating phenotypic variation with specific genes located within the chromosome deletion region. Genome sequencing is recommended in cases where clinical manifestations indicate the presence of a genetic disorder but pose diagnostic challenges.

High Deletion Burden Identified By Whole Genome Sequencing Is Associated with Enhanced Risk in del17p CLL Patients

Presence of deletion17p (del17p) in frontline (1L) and relapsed/refractory (R/R) CLL has been associated with shorter time to treatment initiation, early relapse after therapy and inferior overall survival (OS) (Mato et.al., Haemotologica 2022). However, there exists notable clinical heterogeneity in terms of outcome within this group (Tam et.al., Blood 2009, Stephens et.al; AJH 2015). Previous reports in 1L and R/R CLL have identified percentage of del17p nuclei by fluorescence in situ hybridization (FISH), having TP53 mutations on the second allele, copy number alterations and complex karyotype (CK) as additional risk factors within the del17p population (Yu et al., CCR 2017; Baliakas et al., Blood 2019). Here we profile a cohort of wait and watch (W&amp;W, n=14), 1L treated (n=36) and R/R CLL (n=3) patients by whole genome sequencing (WGS) and RNA sequencing (RNAseq) to gain insights into genomic factors and gene expression pathways contributing to the high-risk nature of del17p across the spectrum of CLL patients. Using the Mayo Clinic CLL Database, we identified 53 patients with del17p (identified by FISH testing in routine clinical practice at diagnosis) who had stored peripheral blood mononuclear cells (PBMCs) available. RNA and DNA from matched peripheral blood (tumor) and DNA from CD19- (germline) samples at diagnosis (n=50) and relapse (n=3) was extracted using Qiagen RNeasy (RNA) and Purene (DNA) kits and subjected to RNAseq and WGS respectively. Additional FISH assays (del11q, trisomy 12, del13q) and CK by chromosomal banding analysis (CBA) were performed. Baseline clinical characteristics, time to first treatment, types of treatment, and survival were abstracted from the CLL Database. The Mayo Clinic IRB approved this study. Copy number analysis identified deletions in 3p, 4p, 8p, 9p, 9q and gains in 2p, 8q, 15q and 17q chromosomal lesions occurring in patients. We explored the association of clinical and genetic factors, and genomic instability signatures with survival to identify high-risk features in del17p patients. Both total number of deletions by WGS and number of chromosomal aberrations by CBA as a continuous variable were significantly associated with unfavorable OS in the entire cohort (n=53) in a univariate analysis (Hazard ratio, HR= 2.29, p= 0.00054 and HR= 2.33, p=0.0054 respectively). However, there was no significant association of number of gained genes by WGS or aneuploidy scores with survival (HR=0.74, p=0.37). In patients with CK data (n=41), deletion burden, but not gains, were highly correlated to chromosomal aberrations by CBA. Using cutpointr package for identifying deletion threshold corresponding to CK≥ 3, we defined patients with deletion burden ≥ 514 as enhanced-high risk (EHR; median OS = 4.83 years) compared to the group with high-risk (HR; median OS=9.94 years) (p=0.025). There was no significant difference in number of deleted genes between WW and treated patients. The EHR group is enriched in patients with high clonal cell fraction of del17p by FISH, unmutated IGHV and CK≥ 3. The EHR group remains significant in a multi-variable analysis with IGHV-mutation status, ZAP70, and age (HR: 5.16, 95% CI: 1.04 - 25.6, p=0.04). Mutational analysis identified 35 known CLL driver mutations with TP53 (86%), ATM (15%), NOTCH1(13%), MGA (13%), CHD2 and MED12(11%) as the top mutated genes. Total number of driver genes mutated was not significantly different between EHR and HR subgroups, but the EHR subset was significantly enriched with mutations in NOTCH1 (21%), and MGA (21%) as compared to no mutations in the HR group in these genes. Deleted genes (≥ 514) was prognostic in bi-allelic TP53 aberration patients as well (p=0.021) Differential expression gene-set enrichment analysis indicated a significant enrichment of DNA repair, cellular response to DNA damage and downregulation of inflammatory responses in the EHR group. CK is a known prognostic marker which includes both chromosomal losses and gains. In this small cohort of del17p we were able to show the prognostic value of deletions only, but not gains, as captured by WGS. Using genome wide sequencing, we identify increasing genomic deletions as a feature of enhanced-high risk del17p. While deletion burden cut-offs identified here are specific to our research method and require further validation in additional independent cohorts, EHR subgroup remained significant after adjusting for other known prognostic variables .

OR17-05 Lysine Demethylase KDM1A And Ectopic Expression Of GIP-Receptor In Somatotropinomas Of Patients With Paradoxical Response To Oral Glucose

Abstract Disclosure: F. Chasseloup: None. L. Tosca: None. D. Regazzo: None. A. Proust: None. M. Hage: None. E. Kuhn: None. C. Jublanc: None. K. Mokhtari: None. S. Salenave: None. S. Gaillard: None. F. Parker: None. A. Boch: None. G. Tachdjian: None. P. Chanson: None. J. Bouligand: None. G. Occhi: None. P. Kamenicky: None. Introduction: Paradoxical increase of GH following oral glucose load has been described in ∼30% of patients with acromegaly and has been related to the ectopic expression of the glucose-dependent insulinotropic polypeptide (GIP) receptor (GIPR) in somatotropinomas. Recently, we identified germline pathogenic variants of lysine demethylase 1A (KDM1A) in patients with GIP-dependent primary bilateral macronodular adrenal hyperplasia with Cushing’s syndrome. Most patients also displayed a deletion of chromosome 1p, including the KDM1A locus in their adrenal tissues, resulting in complete loss of KDM1A expression. The ectopic expression of GIPR in both adrenal and pituitary lesions suggests a common molecular mechanism. The aim of our study was to search for genetic abnormalities of KDM1A in somatotroph pituitary adenomas. Methods: We collected somatotropinoma specimens from acromegalic patients followed in two tertiary endocrine centers in France and one in Italy. Somatic DNA was studied by targeted exome NGS and array-CGH. GIPR and KDM1A expression was quantified in the tumors using digital droplet PCR. Results: We included 186 patients: 108 patients (70.6 %) had a classic pathological GH response after oral glucose load, whereas 45 patients (29.4%) displayed a paradoxical rise of GH concentrations. Patients with a paradoxical response displayed higher IGF-1 levels (360 ± 111.8 % above ULN vs. 309.8 ± 107.3 %, p= 0.0130) and less invasive and smaller tumors (14.5 ± 5.58 mm vs. 18.5 ± 8.73 m, p= 0.0066). Amongst the 146 somatotropinoma specimens analyzed by targeted-NGS, no tumor harbored a KDM1A pathogenic variant, and 35 tumors harbored GNAS mutations (6 with and 29 without paradoxical GH responses). We identified a recurrent 1p deletion encompassing the KDM1A locus in 26 tumors, which were more frequently but not exclusively found in patients with paradoxical GH response compared to those with classic GH response. Somatic deletion of one KMD1A allele was associated with lower KDM1A expression (p=4.5e-5) and higher GIPR expression (p=0.0005). Discussion: Unlike in GIP-dependent PBMAH, we did not identify KDM1A genetic variants in a large cohort of acromegalic patients, independently of their GH response pattern to oral glucose loading. We identified recurrent 1p deletion in some tumors. Pituitary adenomas with a loss of one KDM1A copy due to chromosome 1p deletion harbored higher levels of GIPR transcripts than adenomas diploid for the KDM1A locus. If KDM1A haploinsufficiency leads to partial transcriptional derepression at the GIPR locus and a paradoxical rise of GH after glucose load warrants further investigations. Presentation: Saturday, June 17, 2023

CCDC103 as a Prognostic Biomarker Correlated with Tumor Progression and Immune Infiltration in Glioma.

The Coiled-coil domain-containing proteins (CCDCs) are expressed in many cancers, but the role of Coiled-coil domain-containing protein 103 (CCDC103) in cancers remains unclear. Further investigations are necessary to ascertain its diagnostic significance and understand its biological function in cancers. This study aims to elucidate the biological functionalities of CCDC103 in glioma and evaluate the correlation between CCDC103 expression with glioma progression. Clinical data on glioma patients were acquired from The Cancer Genome Atlas (TCGA), the Chinese Glioma Genome Atlas (CGGA), and the Gene Expression Omnibus (GEO). The evaluation encompassed the examination of correlations between CCDC103 expression, pathological characteristics, and clinical outcomes. Furthermore, the analysis included the assessment of the correlations between CCDC103 expression and immune cell infiltration as well as glioma progression. Gliomas have higher levels of CCDC103 expression than the para-carcinoma tissues. Poorer prognosis, unfavorable histological characteristics, the absence of IDH gene mutations, and the absence of chromosome 1p and 19q deletions were all associated with higher expression of CCDC103 in gliomas. In addition to patient age, tumor grade, the absence of IDH mutations, and the absence of chromosome 1p and 19q deletions, univariate and multivariate Cox analyses showed that CCDC103 expression was independently prognostic of overall survival, disease-free survival, and progression-free survival in patients with glioma. Furthermore, tumor infiltration of B cells, neutrophils, macrophages, and dendritic cells were all linked with elevated expression of CCDC103. High CCDC103 expression was linked to immune response-related signaling pathways and cell proliferation, according to gene set enrichment analysis (GSEA). Notably, the knockdown of CCDC103 in glioma cell lines resulted in a significant reduction in cell proliferation and migration. The correlation between CCDC103 expression and both glioma progression and immune cell infiltration implies that CCDC103 expression holds promise as a valuable prognostic biomarker for glioma.

Comprehensive molecular characterization of adenoid cystic carcinoma reveals tumor suppressors as novel drivers and prognostic biomarkers.

Adenoid cystic carcinoma (ACC) is a MYB-driven head and neck malignancy with high rates of local recurrence and distant metastasis and poor long-term survival. New effective targeted therapies and clinically useful biomarkers for patient stratification are needed to improve ACC patient survival. Here, we present an integrated copy number and transcriptomic analysis of ACC to identify novel driver genes and prognostic biomarkers. A total of 598 ACCs were studied. Clinical follow-up was available from 366 patients, the largest cohort analyzed to date. Copy number losses of 1p36 (70/492; 14%) and of the tumor suppressor gene PARK2 (6q26) (85/343; 25%) were prognostic biomarkers; patients with concurrent losses (n = 20) had significantly shorter overall survival (OS) than those with one or no deletions (p < 0.0001). Deletion of 1p36 independently predicted short OS in multivariate analysis (p = 0.02). Two pro-apoptotic genes, TP73 and KIF1B, were identified as putative 1p36 tumor suppressor genes whose reduced expression was associated with poor survival and increased resistance to apoptosis. PARK2 expression was markedly reduced in tumors with 6q deletions, and PARK2 knockdown increased spherogenesis and decreased apoptosis, indicating that PARK2 is a tumor suppressor in ACC. Moreover, analysis of the global gene expression pattern in 30 ACCs revealed a transcriptomic signature associated with short OS, multiple copy number alterations including 1p36 deletions, and reduced expression of TP73. Taken together, the results indicate that TP73 and PARK2 are novel putative tumor suppressor genes and potential prognostic biomarkers in ACC. Our studies provide new important insights into the pathogenesis of ACC. The results have important implications for biomarker-driven stratification of patients in clinical trials. © 2023 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.

Evaluation of chromosome 1p/19q deletion by Fluorescence in Situ Hybridization (FISH) as prognostic factors in malignant glioma patients on treatment with alkylating chemotherapy

BackgroundEither deletion or co-deletion of chromosomal arms 1p or 19q is a characteristic and early genetic event in oligodendroglial tumors that is associated with a better prognosis and enhanced response to therapy. Information of 1p/19q status is now regarded as the standard of care when managing oligodendroglial tumors for therapeutic options in anticipation of the increased survival and progression-free survival times associated with it. Keeping this in view, we first time attempted to establish the FISH based detection of 1p/19q deletion in glioma tissue samples to evaluate its role and involvement in the disease. MethodOverall 39 glioma cases of different histologies were evaluated by fluorescence in situ hybridization (FISH) technique using specific FISH probes with Olympus BX43 fluorescent microscope to detect chromosomes 1p and 19q or co-deletions therein. ResultsOf the 39 glioma samples, overall 27 (69.2%) were found to have deletion either in 1p, 19q or both. Deletions were observed in 23.0%, 7.6% and 38.4% in 1p, 19q and 1p/19q co-deletions respectively. Overall oligidendrioglioma presented with 53.8% (21 of 39) deletions, astrocytoma group showed 12.8% and GBM accounted for 2.5% deletions. Overall survival and disease free survival was seen significantly better in oligidendrioglioma and astrocytoma with deleted tumors as compared to non-deleted ones (p<0.05). ConclusionAllelic losses on 1p and 19q, either discretely or shared, were more frequent in classic oligodendrogliomas than in either astrocytoma or Glioblastoma with better survival and response to therapy.