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As a promising alternative to bone marrow aspiration (BMA), mutational profiling on blood-derived circulating cell-free tumor DNA (cfDNA) is a harmless and simple technique to monitor molecular response and treatment resistance of patients with refractory/relapsed multiple myeloma (R/R MM). We evaluated the sensitivity and specificity of cfDNA compared to BMA CD138 positive myeloma plasma cells (PCs) in a series of 45 R/R MM patients using the 29-gene targeted panel (AmpliSeq) NGS. KRAS, NRAS, FAM46C, DIS3, and TP53 were the most frequently mutated genes. The average sensitivity and specificity of cfDNA detection were 65% and 97%, respectively. The concordance per gene between the two samples was good to excellent according to Cohen's κ coefficients interpretation. An increased number of mutations detected in cfDNA were associated with a decreased overall survival. In conclusion, we demonstrated cfDNA NGS analysis feasibility and accuracy in R/R MM patients who may benefit from early phase clinical trial. [ABSTRACT FROM AUTHOR]

Introduction: Microsatellite instability (MSI) is a genetic marker that is useful in the detection and treatment of Lynch syndrome (Sd). Although conventional techniques such as immunohistochemistry (IHC) and polymerase chain reaction (PCR) are the standards for MSI detection, the advent of next-generation sequencing (NGS) has offered new possibilities, especially with circulating DNA., Case Report: We present the case of a 26-year-old patient with Lynch Sd and a BRAF -mutated metastatic colon cancer. The discordant MSI results between the conventional methods and NGS posed challenges in making treatment decisions. Subsequent NGS analysis revealed a high MSI status, leading to participation in an immunotherapy trial, with remarkable clinical response., Conclusion: This case emphasizes the importance of comprehensive molecular profiling and strong interdisciplinary collaborations, especially in cases with ambiguous MSI results., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Rodriguez, Vasseur, Bani, Cabaret, Cotteret, Muleris, Golbarg, Malka, Pudlarz, Caron and Smolenschi.)

Mullerian adenosarcoma is a rare malignant biphasic tumor. The mesenchymal component may be low or high grade, with or without sarcomatous overgrowth (SO). Little is known about the molecular heterogeneity of these tumors. In this study, we aim to reclassify a large retrospective monocentric cohort of uterine adenosarcomas according to tumor grade and SO, to evaluate the clinical significance of pathological classification and to correlate with copy-number variations inferred from single nucleotide polymorphism array. Of the 67 uterine adenosarcomas, 18 (26.9%) were low grade without SO, 7 (10.4%) low grade with SO, 8 (11.9%) high grade without SO and 34 (50.7%) high grade with SO. SO, necrosis and RMS were more frequent in high grade than low grade adenosarcomas (p < 0.001). Low-rank test showed that recurrence-free survival was significantly shortened in high grade than low grade adenosarcomas (p = 0.035) and SO was associated with shortened overall and recurrence-free survival (p = 0.038 and p = 0.009, respectively). High-grade tumors displayed complex genomic profiles with multiple segmental losses including TP53, ATM and PTEN genes. The median genomic index was significantly higher in high grade than low grade tumors (27 [3-60] vs 5,3 [0-16], p < 0.0001) and was significantly higher in presence of SO in low grade tumors (12,8 [10-16] vs 2,6 [0-10], p = 0.0006). We propose to report sarcomatous overgrowth with the tumor grade for prognostication in adenosarcoma and representative sampling is crucial for evaluation of these histological criteria., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Next-generation sequencing (NGS) assays based on plasma cell-free DNA (cfDNA) are increasingly used for clinical trials inclusion. Their optimized limit of detection applied to a large number of genes leads to the identification of mutations not confirmed in tissue. It becomes essential to describe the characteristics and consequences of these liquid biopsy-only mutations. In the STING protocol (Gustave Roussy, NCT04932525), 542 patients with advanced solid cancer had cfDNA-based and tissue-based NGS analysis (performed by FoundationOne® Liquid CDx and FoundationOne CDx™, respectively). Mutations identified in the liquid biopsy but not in the paired tissue were considered as liquid biopsy-only mutations irrespective of their variant allelic frequency (VAF). Out of 542 patients, 281 (51.8%) harbored at least one liquid biopsy-only mutation. These patients were significantly older, and more heavily pretreated. Liquid biopsy-only mutations occurring in TP53, and in DDR genes (ATM, CHEK2, ATR, BRCA2, and BRCA1) accounted for 90.8% of all the mutations. The median VAF of these mutations was generally low (0.37% and 0.40% for TP53 and DDR genes respectively). The variant type repartition depended on the gene. Liquid biopsy-only mutations affected hotspot in TP53 codon 273, 125, 195, 176, 237 or 280 and ATM codon 2891 and 3008. In a subset of 37 patients, 75.0%, 53.5% and 83.3% of the liquid biopsy-only mutations occurring respectively in ATM, TP53, and CHEK2 were confirmed in the matching whole blood sample. Although liquid biopsy-only mutations makes the interpretation of liquid biopsy results more complex, they have distinct characteristics making them more easily identifiable., (© 2024. The Author(s).)

The immunodetection of NUT protein is a reliable tool to identify NUT carcinoma, a rare and still underdiagnosed tumor entity. The technique was implemented in 2017 in our department, a tertiary reference center with a large recruitment in all tumor types, including head and neck and thoracic tumors. We evaluated its use over a 6-year period (2017-2022) to (a) describe the indications for the technique, (b) determine the number of NUT carcinomas detected and confirmed by Fluorescence in situ hybridization, and (c) describe briefly the characteristics of these tumors. Over the study period, 382 NUT immunodetections were performed; the annual number of requests varied from 45 to 83. All 21 pathologists of the department made at least one request (range: 1 to 94; annual mean: 18.2). 54.7% of immunodetections were performed for internal cases, 37% for cases submitted for consultation, and 8.3% for cases submitted for confirmation of a suspected diagnosis. The main indications were poorly differentiated tumors of the head and neck region (39%) and the thorax (19.6%), and difficult-to-classify soft tissue tumors (11.8%). Twelve cases of NUT carcinoma were detected by immunohistochemistry and confirmed by Fluorescence in situ hybridization. Seven were from the head and neck region (4.7% of the tumors tested), 4 from lung or mediastinum (5.3%), 1 from an unknown primary at the time of diagnosis. In conclusion, the implementation of NUT immunodetection in the daily workflow of a pathology department improves the detection of NUT carcinoma. This becomes essential with the emergence of potential targeted therapies., Competing Interests: The authors declare no conflict of interest., (Copyright © 2023 Wolters Kluwer Health, Inc. All rights reserved.)

Differential diagnosis between constitutional mismatch repair deficiency (CMMRD) and neurofibromatosis type 1 (NF1 ) is crucial as treatment and surveillance differ. We report the case of a girl with a clinical diagnosis of sporadic NF1 who developed a glioblastoma. Immunohistochemistry for MMR proteins identified PMS2 loss in tumour and normal cells and WES showed the tumour had an ultra-hypermutated phenotype, supporting the diagnosis of CMMRD. Germline analyses identified two variants (one pathogenic variant and one classified as variant(s) of unknown significance) in the PMS2 gene and subsequent functional assays on blood lymphocytes confirmed the diagnosis of CMMRD. The large plexiform neurofibroma of the thigh and the freckling were however more compatible with NF1. Indeed, a NF1 PV (variant allele frequencies of 20%, 3% and 9% and in blood, skin and saliva samples, respectively) was identified confirming a mosaicism for NF1. Retrospective analysis of a French cohort identified NF1 mosaicism in blood DNA in 2 out of 22 patients with CMMRD, underlining the existence of early postzygotic PV of NF1 gene in patients with CMMRD whose tumours have been frequently reported to exhibit somatic NF1 mutations. It highlights the potential role of this pathway in the pathogenesis of CMMRD-associated gliomas and argues in favour of testing MEK inhibitors in this context., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2024. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Background: Knowing the homologous recombination deficiency (HRD) status in advanced epithelial ovarian cancer (EOC) is vital for patient management. HRD is determined by BRCA1/BRCA2 pathogenic variants or genomic instability. However, tumor DNA analysis is inconclusive in 15-19% of cases. Peritoneal fluid, available in > 95% of advanced EOC cases, could serve as an alternative source of cell-free tumor DNA (cftDNA) for HRD testing. Limited data show the feasibility of cancer panel gene testing on ascites cfDNA but no study, to date, has investigated HRD testing., Methods: We collected ascites/peritoneal washings from 53 EOC patients (19 from retrospective cohort and 34 from prospective cohort) and performed a Cancer Gene Panel (CGP) using NGS for TP53/HR genes and shallow Whole Genome Sequencing (sWGS) for genomic instability on cfDNA., Results: cfDNA was detectable in 49 out of 53 patients (92.5%), including those with limited peritoneal fluid. Median cfDNA was 3700 ng/ml, with a turnaround time of 21 days. TP53 pathogenic variants were detected in 86% (42/49) of patients, all with HGSOC. BRCA1 and BRCA2 pathogenic variants were found in 14% (7/49) and 10% (5/49) of cases, respectively. Peritoneal cftDNA showed high sensitivity (97%), specificity (83%), and concordance (95%) with tumor-based TP53 variant detection. NGS CGP on cftDNA identified BRCA2 pathogenic variants in one case where tumor-based testing failed. sWGS on cftDNA provided informative results even when tumor-based genomic instability testing failed., Conclusion: Profiling cftDNA from peritoneal fluid is feasible, providing a significant amount of tumor DNA. This fast and reliable approach enables HRD testing, including BRCA1/2 mutations and genomic instability assessment. HRD testing on cfDNA from peritoneal fluid should be offered to all primary laparoscopy patients., (© 2023. The Author(s).)

Breast cancer is the most common malignancy in woman, and its associated mortality is still rising worldwide. Among all the different subtypes of breast cancer, invasive lobular carcinoma (ILC) is the second most frequent. Several histological variants of ILC currently exist such as solid, alveolar, pleomorphic, tubulo-lobular, and mixed types. Recently, a new variant of ILC with a papillary growth pattern has been described. Here, we make a review of the literature and report the sixth case of a woman suffering from this very uncommon variant. Of note, she had a concomitant axillary lymph node metastasis, a manifestation not yet described so far. Molecular analysis showed CDH1 and PIK3CA mutations, along with similar quantitative chromosomal alterations in both primary and metastasis. Because ILC and papillary carcinoma are managed differently, our aim here is to raise awareness among the pathologists to avoid misdiagnosis of this unusual variant and subsequent inappropriate treatment., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Purpose: Homologous recombination deficiency (HRD) is closely related to PARP inhibitor (PARPi) benefit in ovarian cancer. The capacity of BRCA1 promoter methylation to predict prognosis and HRD status remains unclear. We aimed to correlate BRCA1 promoter methylation levels in patients with high-grade ovarian cancer to HRD status and clinical behavior to assess its clinical relevance., Experimental Design: This is a retrospective monocentric analysis of patients centrally tested for genomic instability score (GIS) by MyChoice CDx (Myriad Genetics). The detection of BRCA1 promoter methylation and quantification of methylation levels were performed by quantitative droplet digital PCR methodology. High BRCA1 methylation was defined as ≥70% and deemed to be associated with homozygous silencing., Results: Of 100 patients, 11% harbored a deleterious BRCA1/2 mutation. GIS was considered positive (score ≥ 42) for 52 patients and negative for 48 patients. Using a 70% cutoff, 19% (15/79) of BRCA wild-type ovarian cancer had high BRCA1 methylation levels. All of the highly methylated tumors were classified as HRD, achieving a positive predictive value of 100%. We detected 14% (11/79) low-methylated tumors (1%-69%), and all of them were also classified as HRD. Mean GIS was 61.5 for BRCAmut, 66.4 for high-BRCAmeth, 58.9 for low-BRCAmeth, and 33.3 for BRCAwt unmethylated (P < 0.001). Low methylation levels detected in samples previously exposed to chemotherapy appeared to be associated with poor outcome post-platinum., Conclusions: Patients with ovarian cancer with high levels of BRCA1 hypermethylation are very likely to have high GIS and therefore represent good candidates for PARPi treatment. These results may be highly relevant to other tumor types for HRD prediction. See related commentary by Garg and Oza, p. 2957., (©2023 American Association for Cancer Research.)

Cancer immunotherapy combinations have recently been shown to improve the overall survival of advanced mesotheliomas, especially for patients responding to those treatments. We aimed to characterize the biological correlates of malignant pleural mesotheliomas' primary resistance to immunotherapy and antiangiogenics by testing the combination of pembrolizumab, an anti-PD-1 antibody, and nintedanib, a pan-antiangiogenic tyrosine kinase inhibitor, in the multicenter PEMBIB trial (NCT02856425). Thirty patients with advanced malignant pleural mesothelioma were treated and explored. Unexpectedly, we found that refractory patients were actively recruiting CD3+CD8+ cytotoxic T cells in their tumors through CXCL9 tumor release upon treatment. However, these patients displayed high levels of somatic copy-number alterations in their tumors that correlated with high blood and tumor levels of IL6 and CXCL8. Those proinflammatory cytokines resulted in higher tumor secretion of VEGF and tumor enrichment in regulatory T cells. Advanced mesothelioma should further benefit from stratified combination therapies adapted to their tumor biology., Significance: Sequential explorations of fresh tumor biopsies demonstrated that mesothelioma resistance to anti-PD-1 + antiangiogenics is not due to a lack of tumor T-cell infiltration but rather due to adaptive immunosuppressive pathways by tumors, involving molecules (e.g., IL6, CXCL8, VEGF, and CTLA4) that are amenable to targeted therapies. This article is highlighted in the In This Issue feature, p. 799., (©2023 The Authors; Published by the American Association for Cancer Research.)

Chimeric antigen receptor (CAR) T-cell therapy is currently approved for the treatment of B-cell non-Hodgkin lymphomas and B-cell acute lymphoblastic leukemia. Prolonged hematological toxicity is an emergent concern following CAR T cells and occurred in 30% of patients with unknown mechanism. Few cases of myelodysplastic syndrome (MDS) following CAR T-cell therapy were reported and attributed to previous chemotherapies in heavily pretreated patients. The authors report the case of a patient with diffuse large B-cell lymphoma treated with axicabtagene ciloleucel who developed prolonged hematological toxicity by day 28. During the follow-up, the diagnosis of MDS was made. The patient underwent allogenic hematological stem cell transplantation. The patient remains in complete remission of his lymphoma and MDS 19 months after hematological stem cell transplantation.

Advances in molecular profiling of newly diagnosed diffuse large B-cell lymphoma (DLBCL) have recently refine genetic subgroups. Genetic subgroups remain undetermined at the time of relapse or refractory (RR) disease. This study aims to decipher genetic subgroups and search for prognostic molecular biomarkers in patients with RR-DLBCL. From 2015 to 2021, targeted next-generation sequencing analyses of germline-matched tumor samples and fresh tissue from RR-DLBCL patients were performed. Unsupervised clustering of somatic mutations was performed and correlations with patient outcome were sought. A number of 120 patients with RR-DLBCL were included in LNH-EP1 study and a molecular tumor landscape was successfully analyzed in 87% of patients (104/120 tumor samples). The median age was 67.5 years (range 27.4-87.4), median number of previous treatments was 2 (range 1-9). The most frequently mutated genes were TP53 (n = 53 mutations; 42% of samples), CREBBP (n = 39; 32%), BCL2 (n = 86; 31%), KMT2D (n = 39; 28%) and PIM1 (n = 54; 22%). Unsupervised clustering separated three genetic subgroups entitled BST (enriched in BCL2, SOCS1, and TNFRSF14 mutations); TKS (enriched in TP53, KMT2D, and STAT6 mutations); and PCM (enriched in PIM1, CD79B, and MYD88 mutations). Median overall survival (OS) was 11.0 (95% confidence interval [CI]: 8.1-12.6) months. OS was not significantly different between the three genetic subgroups. GNA13 mutant was significantly associated with an increased risk of death (hazard ratio: 6.6 [95% CI: 2.1-20.6]; p = .0011) and shorter OS (p = .0340). At the time of relapse or refractory disease, three genetic subgroups of DLBCL patients were delineated, which could help advance precision molecular medicine programs., (© 2023 The Authors. American Journal of Hematology published by Wiley Periodicals LLC.)

Background: Despite that cytogenetic and molecular analysis of tumor cells can rapidly identify recurring molecular abnormalities, no personalized therapy is currently available in the setting of relapsed/refractory multiple myeloma (r/r MM)., Methods: MM-EP1 is a retrospective study aimed at comparing a personalized molecular-oriented (MO) versus a non-molecular-oriented (no-MO) approach in r/r MM. Actionable molecular targets and their associated therapies were the BRAF V600E mutation and BRAF inhibitors; t(11;14)(q13;q32) and BCL2 inhibitors; and t(4;14)(p16;q32) with FGFR3 fusion/rearrangements and FGFR3 inhibitors., Results: One hundred three highly pretreated r/r MM patients with a median age of 67 years (range 44-85) were included. Seventeen (17%) patients were treated using an MO approach with BRAF inhibitors (vemurafenib or dabrafenib, n = 6), BCL2 inhibitor (venetoclax, n = 9), or FGFR3 inhibitor (erdafitinib, n = 2). Eighty-six (86%) patients received non-MO therapies. Overall response rate was 65% in MO patients versus 58% in the non-MO group ( p = 0.053). Median PFS and OS were 9 and 6 months (HR = 0.96; CI95 = 0.51-1.78; p = 0.88) and 26 and 28 months (HR = 0.98; CI95 = 0.46-2.12; p = 0.98), respectively, in MO and no-MO patients., Conclusion: Despite the low number of patients treated with an MO approach, this study highlights the strengths and weakness of a molecular-targeted approach for the treatment of multiple myeloma. Widespread biomolecular techniques and improvement of precision medicine treatment algorithms could improve selection for precision medicine in myeloma.

Extraskeletal myxoid chondrosarcoma (EMC) is a rare soft tissue neoplasm of uncertain lineage characterized by the pathognomonic rearrangement of the NR4A3 gene, which in most cases is fused with EWSR1. Other NR4A3 fusion partners have been described, namely TAF15, FUS, TCF12, and TGF. Some studies suggest that EMCs with non-EWSR1 variant fusion are associated with high-grade morphology and worst clinical behavior compared to EWSR1::NR4A3 tumors, supporting the potential significance of particular fusion variant in EMC. We report a case of a 34-year-old male who presented with calf EMC and subsequently developed a slowly progressive metastatic disease 3 years after diagnosis. Whole-transcriptome analysis with total RNA sequencing enabled identification of a novel fusion transcript LSM14A::NR4A3, expanding the molecular spectrum of EMC., (© 2022 Wiley Periodicals LLC.)

"Juvenile-like (hyperplastic/inflammatory) mucosal polyp" is a term proposed for rare benign mesenchymal lesions of the gastro-intestinal tract so far reported only in patients with type 1 neurofibromatosis (NF1). We report here a first sporadic case of NF1 -associated mucosal inflammatory polyp of the colon. The diagnosis was made in a 53-year old female patient with a large polypoid tumor of the cecum. The lesion was predominantly mucosal, made of fibroblast-like cells associated with inflammatory infiltrates rich in eosinophils and containing entrapped, distorted epithelial glands, responsible for the juvenile-like appearance. Whole exome sequencing showed a pathogenic variant of NF1 . The patient had no evidence of NF1; no NF1 mutation was detected in normal tissues. Our observation may support the existence of juvenile-like inflammatory polyps associated with NF1 alterations, either germline or somatic. This justifies to test NF1 in difficult-to-classify gastrointestinal mesenchymal tumors.

FDA-approved next-generation sequencing assays based on cell-free DNA offers new opportunities in a molecular-tumor-board context thanks to the noninvasiveness of liquid biopsy, the diversity of analyzed parameters and the short turnaround time. It gives the opportunity to study the heterogeneity of the tumor, to elucidate complex resistance mechanisms and to adapt treatment strategies. However, lowering the limit of detection and increasing the panels' size raise new questions in terms of detection of incidental germline alterations, occult malignancies and clonal hematopoiesis of indeterminate potential mutations. In this review, after a technological discussion and description of the common problematics encountered, we establish recommendations in properly using these FDA-approved tests in a molecular-tumor-board context.

Abstract: MAPPYACTS (NCT02613962) is an international prospective precision medicine trial aiming to define tumor molecular profiles in pediatric patients with recurrent/refractory malignancies in order to suggest the most adapted salvage treatment. From February 2016 to July 2020, 787 patients were included in France, Italy, Ireland, and Spain. At least one genetic alteration leading to a targeted treatment suggestion was identified in 436 patients (69%) with successful sequencing; 10% of these alterations were considered "ready for routine use." Of 356 patients with follow-up beyond 12 months, 107 (30%) received one or more matched targeted therapies-56% of them within early clinical trials-mainly in the AcSé-ESMART platform trial (NCT02813135). Overall, matched treatment resulted in a 17% objective response rate, and of those patients with ready for routine use alterations, it was 38%. In patients with extracerebral tumors, 76% of actionable alterations detected in tumor tissue were also identified in circulating cell-free DNA (cfDNA)., Significance: MAPPYACTS underlines the feasibility of molecular profiling at cancer recurrence in children on a multicenter, international level and demonstrates benefit for patients with selected key drivers. The use of cfDNA deserves validation in prospective studies. Our study highlights the need for innovative therapeutic proof-of-concept trials that address the underlying cancer complexity. This article is highlighted in the In This Issue feature, p. 1171., (©2022 The Authors; Published by the American Association for Cancer Research.)

Alveolar rhabdomyosarcoma (ARMS) is associated with PAX3/PAX7-FOXO1 fusion, which confers specific clinic and biologic characteristics with inferior outcomes. A minority of tumors still histologically classified as "true" ARMS lack the canonical PAX-FOXO1 fusion but have new molecular alterations. We present the first case of PAX3-NCOA1 ARMS with clinical data and follow-up in a two-year-old girl with ARMS of the tongue and nodal extension, treated with chemotherapy, hemi glossectomy, lymph node dissection, and brachytherapy to conserve oral function and limit long-term sequelae. Given the rarity of such variant fusion in ARMS, international collaboration is required to evaluate its prognostic value., (© 2021 The Authors. Pediatric Blood & Cancer published by Wiley Periodicals LLC.)

Context.—: Errors in laboratory medicine could compromise patient safety. Good laboratory practice includes identifying and managing nonconformities in the total test process. Varying error percentages have been described in other fields but are lacking for molecular oncology., Objectives.—: To gain insight into incident causes and frequency in the total test process from 8 European institutes routinely performing biomarker tests in non-small cell lung cancer and colorectal cancer., Design.—: All incidents documented in 2018 were collected from all hospital services for pre-preanalytical entries before the biomarker test, as well as specific incidents for biomarker tests., Results.—: There were 5185 incidents collected, of which 4363 (84.1%) occurred in the pre-preanalytical phase (all hospital services), 2796 of 4363 (64.1%) related to missing or incorrect request form information. From the other 822 specific incidents, 166 (20.2%) were recorded in the preanalytical phase, 275 (33.5%) in the analytical phase, and 194 (23.6%) in the postanalytical phase, mainly due to incorrect report content. Only 47 of 822 (5.7%) incidents were recorded in the post-postanalytical phase, and 123 (15.0%) in the complete total test process. For 17 of 822 (2.1%) incidents the time point was unknown. Pre-preanalytical incidents were resolved sooner than incidents on the complete process (mean 6 versus 60 days). For 1215 of 5168 (23.5%) incidents with known causes a specific action was undertaken besides documenting them, not limited to accredited institutes., Conclusions.—: There was a large variety in the number and extent of documented incidents. Correct and complete information on the request forms and final reports are highly error prone and require additional focus.

Thalidomide analogs exert their therapeutic effects by binding to the CRL4 CRBN E3 ubiquitin ligase, promoting ubiquitination and subsequent proteasomal degradation of specific protein substrates. Drug-induced degradation of IKZF1 and IKZF3 in B-cell malignancies demonstrates the clinical utility of targeting disease-relevant transcription factors for degradation. Here, we found that avadomide (CC-122) induces CRBN-dependent ubiquitination and proteasomal degradation of ZMYM2 (ZNF198), a transcription factor involved in balanced chromosomal rearrangements with FGFR1 and FLT3 in aggressive forms of hematologic malignancies. The minimal drug-responsive element of ZMYM2 is a zinc-chelating MYM domain and is contained in the N-terminal portion of ZMYM2 that is universally included in the derived fusion proteins. We demonstrate that avadomide has the ability to induce proteasomal degradation of ZMYM2-FGFR1 and ZMYM2-FLT3 chimeric oncoproteins, both in vitro and in vivo . Our findings suggest that patients with hematologic malignancies harboring these ZMYM2 fusion proteins may benefit from avadomide treatment., Competing Interests: Disclosure of potential conflicts of interest B.L. Ebert has received research funding from Celgene and Deerfield. He has received consulting fees from GRAIL, and he serves on the scientific advisory boards for Skyhawk Therapeutics, Exo Therapeutics, and Neomorph Therapeutics. S.A. Carr is a member of the scientific advisory boards of Kymera, PTM BioLabs and Seer and a scientific advisor to Pfizer and Biogen.

The immunosurveillance mechanisms governing high-risk neuroblastoma (HR-NB), a major pediatric malignancy, have been elusive. We identify a potential role for natural killer (NK) cells, in particular the interaction between the NK receptor NKp30 and its ligand, B7-H6, in the metastatic progression and survival of HR-NB after myeloablative multimodal chemotherapy and stem cell transplantation. NB cells expressing the NKp30 ligand B7-H6 stimulated NK cells in an NKp30-dependent manner. Serum concentration of soluble B7-H6 correlated with the down-regulation of NKp30, bone marrow metastases, and chemoresistance, and soluble B7-H6 contained in the serum of HR-NB patients inhibited NK cell functions in vitro. The expression of distinct NKp30 isoforms affecting the polarization of NK cell functions correlated with 10-year event-free survival in three independent cohorts of HR-NB in remission from metastases after induction chemotherapy (n = 196, P < 0.001), adding prognostic value to known risk factors such as N-Myc amplification and age >18 months. We conclude that the interaction between NKp30 and B7-H6 may contribute to the fate of NB patients and that both the expression of NKp30 isoforms on circulating NK cells and the concentration of soluble B7-H6 in the serum may be clinically useful as biomarkers for risk stratification., (Copyright © 2015, American Association for the Advancement of Science.)

Docetaxel is used as a standard treatment in patients with metastatic castration-resistant prostate cancer. However, a large subset of patients develops resistance. Understanding resistance mechanisms, which are largely unknown, will allow identification of predictive biomarkers and therapeutic targets. We established resistant IGR-CaP1 prostate cancer cell lines for different doses of Docetaxel. We investigated gene expression profiles by microarray analyses in these cell lines and generated a signature of 99 highly differentially expressed genes potentially implicated in chemoresistance. We focused on the role of the cell cycle regulator LZTS1, which was under-expressed in the Docetaxel-resistant cell lines, its inhibition resulting from the promoter methylation. Knockdown of LZTS1 in parental cells with siRNA showed that LZTS1 plays a role in the acquisition of the resistant phenotype. Furthermore, we observed that targeting CDC25C, a partner of LZTS1, with the NSC663284 inhibitor specifically killed the Docetaxel-resistant cells. To further investigate the role of CDC25C, we used inhibitors of the mitotic kinases that regulate CDC25C. Inhibition of CHEK1 and PLK1 induced growth arrest and cell death in the resistant cells. Our findings identify an important role of LZTS1 through its regulation of CDC25C in Docetaxel resistance in prostate cancer and suggest that CDC25C, or the mitotic kinases CHEK1 and PLK1, could be efficient therapeutic targets to overcome Docetaxel resistance.

Protein tyrosine phosphatase (PTP)1B is an abundant non-transmembrane enzyme that plays a major role in regulating insulin and leptin signaling. Recently, we reported that PTP1B is inhibited by sumoylation, and that sumoylated PTP1B accumulates in a perinuclear distribution, consistent with its known localization in the endoplasmic reticulum (ER) and the contiguous outer nuclear membrane. Here, we report that, in addition to its localization at the ER, PTP1B also is found at the inner nuclear membrane, where it is heavily sumoylated. We also find that PTP1B interacts with emerin, an inner nuclear membrane protein that is known to be tyrosine phosphorylated, and that PTP1B expression levels are inversely correlated with tyrosine phosphorylation levels of emerin. PTP1B sumoylation greatly increases as cells approach mitosis, corresponding to the stage where tyrosine phosphorylation of emerin is maximal. In addition, expression of a non-sumoylatable mutant of PTP1B greatly reduced levels of emerin tyrosine phosphorylation. These results suggest that PTP1B regulates the tyrosine phosphorylation of a key inner nuclear membrane protein in a sumoylation- and cell-cycle-dependent manner.