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2.
Nat Commun ; 14(1): 8373, 2023 Dec 15.
Article in English | MEDLINE | ID: mdl-38102140

ABSTRACT

Rhabdomyosarcomas (RMS) are pediatric mesenchymal-derived malignancies encompassing PAX3/7-FOXO1 Fusion Positive (FP)-RMS, and Fusion Negative (FN)-RMS with frequent RAS pathway mutations. RMS express the master myogenic transcription factor MYOD that, whilst essential for survival, cannot support differentiation. Here we discover SKP2, an oncogenic E3-ubiquitin ligase, as a critical pro-tumorigenic driver in FN-RMS. We show that SKP2 is overexpressed in RMS through the binding of MYOD to an intronic enhancer. SKP2 in FN-RMS promotes cell cycle progression and prevents differentiation by directly targeting p27Kip1 and p57Kip2, respectively. SKP2 depletion unlocks a partly MYOD-dependent myogenic transcriptional program and strongly affects stemness and tumorigenic features and prevents in vivo tumor growth. These effects are mirrored by the investigational NEDDylation inhibitor MLN4924. Results demonstrate a crucial crosstalk between transcriptional and post-translational mechanisms through the MYOD-SKP2 axis that contributes to tumorigenesis in FN-RMS. Finally, NEDDylation inhibition is identified as a potential therapeutic vulnerability in FN-RMS.


Subject(s)
Rhabdomyosarcoma , Humans , Carcinogenesis/genetics , Cell Line, Tumor , Rhabdomyosarcoma/genetics , Rhabdomyosarcoma/pathology , Transcription Factors , Cell Transformation, Neoplastic , Cell Differentiation
3.
Clin Epigenetics ; 15(1): 167, 2023 10 19.
Article in English | MEDLINE | ID: mdl-37858275

ABSTRACT

BACKGROUND: Rhabdomyosarcomas (RMS) are predominantly paediatric sarcomas thought to originate from muscle precursor cells due to impaired myogenic differentiation. Despite intensive treatment, 5-year survival for patients with advanced disease remains low (< 30%), highlighting a need for novel therapies to improve outcomes. Differentiation therapeutics are agents that induce differentiation of cancer cells from malignant to benign. The histone methyltransferase, Enhancer of Zeste Homolog 2 (EZH2) suppresses normal skeletal muscle differentiation and is highly expressed in RMS tumours. RESULTS: We demonstrate combining inhibition of the epigenetic modulator EZH2 with the differentiating agent retinoic acid (RA) is more effective at reducing cell proliferation in RMS cell lines than single agents alone. In PAX3-FOXO1 positive RMS cells this is due to an RA-driven induction of the interferon pathway resulting in apoptosis. In fusion negative RMS, combination therapy led to an EZH2i-driven upregulation of myogenic signalling resulting in differentiation. In both subtypes, EZH2 is significantly associated with enrichment of trimethylated lysine 27 on histone 3 (H3K27me3) in genes that are downregulated in untreated RMS cells and upregulated with EZH2 inhibitor treatment. These results provide insight into the mechanism that drives the anti-cancer effect of the EZH2/RA single agent and combination treatment and indicate that the reduction of EZH2 activity combined with the induction of RA signalling represents a potential novel therapeutic strategy to treat both subtypes of RMS. CONCLUSIONS: The results of this study demonstrate the potential utility of combining EZH2 inhibitors with differentiation agents for the treatment of paediatric rhabdomyosarcomas. As EZH2 inhibitors are currently undergoing clinical trials for adult and paediatric solid tumours and retinoic acid differentiation agents are already in clinical use this presents a readily translatable potential therapeutic strategy. Moreover, as inhibition of EZH2 in the poor prognosis FPRMS subtype results in an inflammatory response, it is conceivable that this strategy may also synergise with immunotherapies for a more effective treatment in these patients.


Subject(s)
Enhancer of Zeste Homolog 2 Protein , Rhabdomyosarcoma , Humans , Child , Enhancer of Zeste Homolog 2 Protein/metabolism , Tretinoin/pharmacology , Tretinoin/metabolism , DNA Methylation , Rhabdomyosarcoma/drug therapy , Rhabdomyosarcoma/genetics , Cell Differentiation , Enzyme Inhibitors/pharmacology , Apoptosis , Cell Line, Tumor
4.
Article in English | MEDLINE | ID: mdl-37788156

ABSTRACT

BACKGROUND: Existing patient-reported outcome measures (PROMs) for chronic rhinosinusitis (CRS) use a variety of recall periods and response scales to assess CRS symptom burden. Global perspectives of CRS patients regarding optimal recall periods and response scales for CRS PROMs are unknown. METHODS: This was a multi-center, cross-sectional study recruiting 461 CRS patients from sites across the United States, Saudi Arabia, New Zealand, and Austria. Participants chose which CRS symptom recall period (1 day, 2 weeks, 1 month, >1 month) was most reflective of their current disease state and upon which to best base treatment recommendations (including surgery). Participants also chose which of six response scales (one visual analogue scale and five Likert scales ranging from four to eight items) was easiest to use, understand, and preferred. RESULTS: A plurality of participants (40.0%) felt their CRS symptoms' current state was best reflected by a 1-month recall period. However, most patients (56.9%) preferred treatment recommendations to be determined by symptoms experienced over a >1 month period. The four- and five-item Likert scales were the easiest to understand (26.0% and 25.4%, respectively) and use (23.4% and 26.7%, respectively). The five-item (26.4% rating it most preferred and 70.9% rating it preferred) and four-item Likert (22.3% rating it most preferred and 56.4% rating it preferred) response scales were most preferred. CONCLUSION: Future PROMs for CRS should consider assessment of symptoms over a 1-month period and use a four- or five-item Likert response scale to reflect global patient preferences. These findings also inform interpretation of current CRS PROMs.

5.
Cancer Treat Rev ; 119: 102600, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37467626

ABSTRACT

Neuroblastoma is one of the commonest extra-cranial pediatric tumors, and accounts for over 15% of all childhood cancer mortality. Risk stratification for children with neuroblastoma is based on age, stage, histology, and tumor cytogenetics. The majority of patients are considered to have high-risk neuroblastoma, for which the long-term survival is less than 50%. Current treatments combine surgical resection, chemotherapy, stem cell transplantation, radiotherapy, anti-GD2 based immunotherapy as well as the differentiating agent isotretinoin. Despite the intensive multimodal therapies applied, there are high relapse rates, and recurrent disease is often resistant to further therapy. Enhancer of Zeste Homolog 2 (EZH2), a catalytic subunit of Polycomb Repressive Complex 2 (PRC2), is a histone methyltransferase that represses transcription through trimethylation of lysine residue K27 on histone H3 (H3K27me3). It is responsible for epigenetic repression of transcription, making EZH2 an essential regulator for cell differentiation. Overexpression of EZH2 has been shown to promote tumorigenesis, cancer cell proliferation and prevent tumor cells from differentiating in a number of cancers. Therefore, research has been ongoing for the past decade, developing treatments that target EZH2 in neuroblastoma. This review summarises the role of EZH2 in neuroblastoma and evaluates the latest research findings on the therapeutic potential of targeting EZH2 in the treatment of neuroblastoma.


Subject(s)
Enhancer of Zeste Homolog 2 Protein , Neuroblastoma , Humans , Child , Enhancer of Zeste Homolog 2 Protein/genetics , Cell Line, Tumor , Neoplasm Recurrence, Local , Polycomb Repressive Complex 2 , Neuroblastoma/genetics , Neuroblastoma/therapy , Neuroblastoma/pathology
6.
Eur J Surg Oncol ; 49(11): 106986, 2023 11.
Article in English | MEDLINE | ID: mdl-37463827

ABSTRACT

BACKGROUND: Rising workflow pressures within the oesophageal cancer (OC) multidisciplinary team (MDT) can lead to variability in decision-making, and health inequality. Machine learning (ML) offers a potential automated data-driven approach to address inconsistency and standardize care. The aim of this experimental pilot study was to develop ML models able to predict curative OC MDT treatment decisions and determine the relative importance of underlying decision-critical variables. METHODS: Retrospective complete-case analysis of oesophagectomy patients ± neoadjuvant chemotherapy (NACT) or chemoradiotherapy (NACRT) between 2010 and 2020. Established ML algorithms (Multinomial Logistic regression (MLR), Random Forests (RF), Extreme Gradient Boosting (XGB)) and Decision Tree (DT) were used to train models predicting OC MDT treatment decisions: surgery (S), NACT + S or NACRT + S. Performance metrics included Area Under the Curve (AUC), Accuracy, Kappa, LogLoss, F1 and Precision -Recall AUC. Variable importance was calculated for each model. RESULTS: We identified 399 cases with a male-to-female ratio of 3.6:1 and median age of 66.1yrs (range 32-83). MLR outperformed RF, XGB and DT across performance metrics (mean AUC of 0.793 [±0.045] vs 0.757 [±0.068], 0.740 [±0.042], and 0.709 [±0.021] respectively). Variable importance analysis identified age as a major factor in the decision to offer surgery alone or NACT + S across models (p < 0.05). CONCLUSIONS: ML techniques can use limited feature-sets to predict curative UGI MDT treatment decisions. Explainable Artificial Intelligence methods provide insight into decision-critical variables, highlighting underlying subconscious biases in cancer care decision-making. Such models may allow prioritization of caseload, improve efficiency, and offer data-driven decision-assistance to MDTs in the future.


Subject(s)
Artificial Intelligence , Esophageal Neoplasms , Humans , Adult , Middle Aged , Aged , Aged, 80 and over , Retrospective Studies , Health Status Disparities , Pilot Projects , Machine Learning , Esophageal Neoplasms/therapy , Patient Care Team
7.
Cancers (Basel) ; 15(10)2023 May 18.
Article in English | MEDLINE | ID: mdl-37345159

ABSTRACT

Rhabdomyosarcoma (RMS), the most common soft-tissue sarcoma in children and adolescents, represents an aberrant form of skeletal muscle differentiation. Both skeletal muscle development, as well as regeneration of adult skeletal muscle are governed by members of the myogenic family of regulatory transcription factors (MRFs), which are deployed in a highly controlled, multi-step, bidirectional process. Many aspects of this complex process are deregulated in RMS and contribute to tumorigenesis. Interconnected loops of super-enhancers, called core regulatory circuitries (CRCs), define aberrant muscle differentiation in RMS cells. The transcriptional regulation of MRF expression/activity takes a central role in the CRCs active in skeletal muscle and RMS. In PAX3::FOXO1 fusion-positive (PF+) RMS, CRCs maintain expression of the disease-driving fusion oncogene. Recent single-cell studies have revealed hierarchically organized subsets of cells within the RMS cell pool, which recapitulate developmental myogenesis and appear to drive malignancy. There is a large interest in exploiting the causes of aberrant muscle development in RMS to allow for terminal differentiation as a therapeutic strategy, for example, by interrupting MEK/ERK signaling or by interfering with the epigenetic machinery controlling CRCs. In this review, we provide an overview of the genetic and epigenetic framework of abnormal muscle differentiation in RMS, as it provides insights into fundamental mechanisms of RMS malignancy, its remarkable phenotypic diversity and, ultimately, opportunities for therapeutic intervention.

8.
Otolaryngol Head Neck Surg ; 169(2): 221-226, 2023 08.
Article in English | MEDLINE | ID: mdl-36807128

ABSTRACT

OBJECTIVE: Primary chronic rhinosinusitis (CRS) is typically a diffuse process and the extent of endoscopic sinus surgery (ESS) performed for medically recalcitrant CRS is impacted by many factors. However, some third-party payors have implemented policies to authorize coverage for ESS in a sinus-by-sinus manner based on a minimal measurement of millimeters of mucosal thickening or sinus opacification in the corresponding sinus that is being surgically addressed. Our objective was to determine whether such policies are based on scientific evidence that in patients with medically recalcitrant CRS, a minimum measurement of mucosal thickening or sinus opacification is a predictor of CRS in that sinus or improved outcomes after ESS on a sinus-by-sinus basis. DATA SOURCES: Medline, Embase, Scopus, and Web of Science databases, from inception through May 2022. REVIEW METHODS: A systematic review was performed. The Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines were followed. RESULTS: We identified 6070 abstracts which were screened and from which 112 studies ultimately underwent a full-text review. From these studies, we found that none investigated (or provided evidence of) whether any minimal degree of radiographic mucosal thickening or sinus opacification predicted CRS or better outcomes after ESS in a sinus-specific manner. CONCLUSION: We were unable to find evidence supporting a minimum millimeter measurement of mucosal thickening or sinus opacification as predictors of CRS or better post-ESS outcomes in a sinus-specific manner in patients with medically recalcitrant CRS. The extent of ESS for CRS should be determined through personalized medical decision-making that considers all patient-specific factors.


Subject(s)
Paranasal Sinuses , Rhinitis , Sinusitis , Humans , Rhinitis/diagnostic imaging , Rhinitis/surgery , Paranasal Sinuses/diagnostic imaging , Paranasal Sinuses/surgery , Sinusitis/diagnostic imaging , Sinusitis/surgery , Endoscopy , Chronic Disease
9.
Cancer Metastasis Rev ; 42(1): 335-359, 2023 03.
Article in English | MEDLINE | ID: mdl-36723696

ABSTRACT

Pseudomyxoma peritonei (PMP) is a rare, progressive, slowly growing neoplastic condition which is poorly understood, with a 5-year progression-free survival rate as low as 48%. PMP is most commonly caused by appendiceal mucinous neoplasms (AMN), and understanding their genetic biology and pathogenicity may allow for the development of better novel systemic treatments to target key deleterious mutations and the implicated pathways. The primary aim of this systematic review was to identify the genetic profile of histologically confirmed human PMP or AMN samples. The secondary aim was to identify whether genetic marks could be used to predict patient survival. Ovid EMBASE, Ovid MEDLINE, PubMed, and Web of Science were searched to identify studies investigating the genetic profile of histologically-confirmed human PMP or AMN samples. We review findings of 46 studies totalling 2181 tumour samples. The most frequently identified somatic gene mutations in patients with PMP included KRAS (38-100%), GNAS (17-100%), and TP53 (5-23%); however, there were conflicting results of their effect on survival. Three studies identified molecular subtypes based on gene expression profiles classifying patients into oncogene-enriched, immune-enriched, and mixed molecular subtypes with prognostic value. This review summarises the current literature surrounding genetic aberrations in PMP and AMNs and their potential utility for targeted therapy. Given the recent advances in clinical trials to directly target KRAS and GNAS mutations in other cancers, we propose a rationale to explore these mutations in future pre-clinical studies in PMP with a view for a future clinical trial.


Subject(s)
Appendiceal Neoplasms , Peritoneal Neoplasms , Pseudomyxoma Peritonei , Humans , Pseudomyxoma Peritonei/genetics , Pseudomyxoma Peritonei/pathology , Peritoneal Neoplasms/genetics , Appendiceal Neoplasms/genetics , Appendiceal Neoplasms/pathology , Genetic Profile , Proto-Oncogene Proteins p21(ras)/genetics
11.
Otolaryngol Head Neck Surg ; 168(3): 330-338, 2023 03.
Article in English | MEDLINE | ID: mdl-35943813

ABSTRACT

OBJECTIVE: Otolaryngology is a surgical field with a high degree of ergonomic risk. The use of head-mounted lighting, loupe magnification, endoscopes, and microscopes is inherent to the field, coupled with repetitive fine motor movements in a constrained anatomic field as well as static, ergonomically unfavorable postures. We seek to review the otolaryngologic literature on ergonomics, including prevalence, severity, and interventions in decreasing work-related musculoskeletal pain. DATA SOURCES: Data were derived from clinical peer-reviewed primary literature as well as information provided by residency programs and presented at national and international meetings. REVIEW METHODS: A comprehensive review was performed by 3 independent reviewers utilizing an electronic database literature search through PubMed, Embase, and Cochrane Library. Search terms included combinations and variations of the following concepts: ergonomics, surgery, otolaryngology, work related musculoskeletal disorders, chronic cervical pain, musculoskeletal, posture, surveys, microsurgery, endoscopic surgery. Strict objective criteria for inclusion were not used due to the inherent heterogeneity in articles and lack of rigorous empirical evidence. CONCLUSIONS: Chronic musculoskeletal pain is prevalent among otolaryngologic surgeons, with many procedures producing high ergonomic risk. Most studies evaluating interventions to decrease ergonomic risks demonstrate promising results, but standardization in methods and outcome reporting is needed. IMPLICATIONS FOR PRACTICE: Literature shows that musculoskeletal pain begins in training, and there is a paucity of information related to ergonomic risk in otolaryngology residency curriculums. Work-related musculoskeletal disorders related to poor workplace ergonomics have the potential to limit career longevity and lead to physician burnout. Interventions to mitigate this risk are effective and tend to be well received by physicians.


Subject(s)
Musculoskeletal Diseases , Musculoskeletal Pain , Occupational Diseases , Humans , Occupational Diseases/prevention & control , Ergonomics/methods , Musculoskeletal Diseases/prevention & control , Surveys and Questionnaires , Otorhinolaryngologic Surgical Procedures
12.
Laryngoscope Investig Otolaryngol ; 7(4): 935-942, 2022 Aug.
Article in English | MEDLINE | ID: mdl-36000029

ABSTRACT

Objectives: Acute exacerbations of chronic rhinosinusitis (AECRS) are distinct from baseline symptomatology related to chronic rhinosinusitis (CRS). In this review, we seek to examine the literature on AECRS to synthesize the definition, epidemiology, pathophysiology, treatment, and impact of AECRS on CRS patients. Methods: A comprehensive narrative review of the scientific literature, identified by searching PubMed from inception through April 2022, was performed. Results: AECRS is defined in consensus guidelines as a worsening of chronic sinus disease symptomatology, with a return to baseline, typically after intervention with systemic antibiotics and/or corticosteroids. The working definition used across the literature, however, is broad and heterogeneous. The pathophysiology of AECRS is incompletely understood but is hypothesized to include an interplay of environmental and patient-specific factors. AECRS have been found to have a negative impact on quality-of-life measures, independent of baseline CRS symptomatology, and impact how patients and physicians view overall disease control. Treatment for AECRS includes oral antibiotics and systemic corticosteroids, although their efficacy for AECRS is unclear. Appropriate use of medical and surgical treatment for CRS can reduce the frequency of AECRS. Conclusions: AECRS are a distinct entity in CRS patients and should be independently assessed when evaluating patients for CRS control. The efficacy of systemic medication usage for AECRS is currently unclear, but appropriate medical management of baseline CRS can reduce the frequency of AECRS. More research is needed to further understand this phenomenon, including a more precise and prospective definition, defined epidemiology, and how to appropriately treat. Level of Evidence: 5.

13.
Biochim Biophys Acta Gene Regul Mech ; 1865(5): 194848, 2022 07.
Article in English | MEDLINE | ID: mdl-35905858

ABSTRACT

Histone modifying enzymes are involved in the posttranslational modification of histones and the epigenetic control of gene expression. They play a critical role in normal development, and there is increasing evidence of their role in developmental disorders (DDs). DDs are a group of chronic, severe conditions that impact the physical, intellectual, language and/or behavioral development of an individual. There are very few treatment options available for DDs such that these are conditions with significant unmet clinical need. Recessive variants in the gene encoding histone modifying enzyme KDM5B are associated with a DD characterized by developmental delay, facial dysmorphism and camptodactyly. KDM5B is responsible for the demethylation of lysine 4 on the amino tail of histone 3 and plays a vital role in normal development and regulating cell differentiation. This review explores the literature on KDM5B and what is currently known about its roles in development and developmental disorders.


Subject(s)
Histones , Jumonji Domain-Containing Histone Demethylases , Child , Developmental Disabilities/genetics , Histones/genetics , Histones/metabolism , Humans , Jumonji Domain-Containing Histone Demethylases/genetics , Jumonji Domain-Containing Histone Demethylases/metabolism , Nuclear Proteins/metabolism , Repressor Proteins/metabolism
14.
Cell Rep Med ; 3(6): 100541, 2022 06 21.
Article in English | MEDLINE | ID: mdl-35732148

ABSTRACT

The chemotherapy resistance of esophageal adenocarcinomas (EACs) is underpinned by cancer cell extrinsic mechanisms of the tumor microenvironment (TME). We demonstrate that, by targeting the tumor-promoting functions of the predominant TME cell type, cancer-associated fibroblasts (CAFs) with phosphodiesterase type 5 inhibitors (PDE5i), we can enhance the efficacy of standard-of-care chemotherapy. In ex vivo conditions, PDE5i prevent the transdifferentiation of normal fibroblasts to CAF and abolish the tumor-promoting function of established EAC CAFs. Using shotgun proteomics and single-cell RNA-seq, we reveal PDE5i-specific regulation of pathways related to fibroblast activation and tumor promotion. Finally, we confirm the efficacy of PDE5i in combination with chemotherapy in close-to-patient and in vivo PDX-based model systems. These findings demonstrate that CAFs drive chemotherapy resistance in EACs and can be targeted by repurposing PDE5i, a safe and well-tolerated class of drug administered to millions of patients world-wide to treat erectile dysfunction.


Subject(s)
Adenocarcinoma , Cancer-Associated Fibroblasts , Esophageal Neoplasms , Adenocarcinoma/drug therapy , Cancer-Associated Fibroblasts/metabolism , Esophageal Neoplasms/drug therapy , Humans , Male , Phosphodiesterase 5 Inhibitors/pharmacology , Tumor Microenvironment
15.
Mol Oncol ; 16(6): 1272-1289, 2022 03.
Article in English | MEDLINE | ID: mdl-34850536

ABSTRACT

Rhabdomyosarcomas are aggressive pediatric soft-tissue sarcomas and include high-risk PAX3-FOXO1 fusion-gene-positive cases. Fibroblast growth factor receptor 4 (FGFR4) is known to contribute to rhabdomyosarcoma progression; here, we sought to investigate the involvement and potential for therapeutic targeting of other FGFRs in this disease. Cell-based screening of FGFR inhibitors with potential for clinical repurposing (NVP-BGJ398, nintedanib, dovitinib, and ponatinib) revealed greater sensitivity of fusion-gene-positive versus fusion-gene-negative rhabdomyosarcoma cell lines and was shown to be correlated with high expression of FGFR2 and its specific ligand, FGF7. Furthermore, patient samples exhibit higher mRNA levels of FGFR2 and FGF7 in fusion-gene-positive versus fusion-gene-negative rhabdomyosarcomas. Sustained intracellular mitogen-activated protein kinase (MAPK) activity and FGF7 secretion into culture media during serum starvation of PAX3-FOXO1 rhabdomyosarcoma cells together with decreased cell viability after genetic silencing of FGFR2 or FGF7 was in keeping with a novel FGF7-FGFR2 autocrine loop. FGFR inhibition with NVP-BGJ398 reduced viability and was synergistic with SN38, the active metabolite of irinotecan. In vivo, NVP-BGJ398 abrogated xenograft growth and warrants further investigation in combination with irinotecan as a therapeutic strategy for fusion-gene-positive rhabdomyosarcomas.


Subject(s)
Autocrine Communication , Rhabdomyosarcoma , Cell Line, Tumor , Child , Drug Resistance, Neoplasm , Fibroblast Growth Factor 7 , Humans , Irinotecan , Protein Kinase Inhibitors/pharmacology , Receptor, Fibroblast Growth Factor, Type 2 , Rhabdomyosarcoma/drug therapy , Rhabdomyosarcoma/genetics
16.
Cancers (Basel) ; 13(16)2021 Aug 13.
Article in English | MEDLINE | ID: mdl-34439236

ABSTRACT

Oesophageal adenocarcinoma (OAC) has a dismal prognosis, where curable disease occurs in less than 40% of patients, and many of those with incurable disease survive for less than a year from diagnosis. Despite the widespread use of systematic chemotherapy in OAC treatment, many patients receive no benefit. New treatments are urgently needed for OAC patients. There is an emerging interest in epigenetic regulators in cancer pathogenesis, which are now translating into novel cancer therapeutic strategies. Histone-modifying enzymes (HMEs) are key epigenetic regulators responsible for dynamic covalent histone modifications that play roles in both normal and dysregulated cellular processes including tumorigenesis. Several HME inhibitors are in clinical use for haematological malignancies and sarcomas, with numerous on-going clinical trials for their use in solid tumours. This review discusses the current literature surrounding HMEs in OAC pathogenesis and their potential use in targeted therapies for this disease.

17.
Cancers (Basel) ; 13(14)2021 Jul 06.
Article in English | MEDLINE | ID: mdl-34298611

ABSTRACT

Neoadjuvant therapy followed by surgery is the standard of care for locally advanced esophageal adenocarcinoma (EAC). Unfortunately, response to neoadjuvant chemotherapy (NAC) is poor (20-37%), as is the overall survival benefit at five years (9%). The EAC genome is complex and heterogeneous between patients, and it is not yet understood whether specific mutational patterns may result in chemotherapy sensitivity or resistance. To identify associations between genomic events and response to NAC in EAC, a comparative genomic analysis was performed in 65 patients with extensive clinical and pathological annotation using whole-genome sequencing (WGS). We defined response using Mandard Tumor Regression Grade (TRG), with responders classified as TRG1-2 (n = 27) and non-responders classified as TRG4-5 (n =38). We report a higher non-synonymous mutation burden in responders (median 2.08/Mb vs. 1.70/Mb, p = 0.036) and elevated copy number variation in non-responders (282 vs. 136/patient, p < 0.001). We identified copy number variants unique to each group in our cohort, with cell cycle (CDKN2A, CCND1), c-Myc (MYC), RTK/PIK3 (KRAS, EGFR) and gastrointestinal differentiation (GATA6) pathway genes being specifically altered in non-responders. Of note, NAV3 mutations were exclusively present in the non-responder group with a frequency of 22%. Thus, lower mutation burden, higher chromosomal instability and specific copy number alterations are associated with resistance to NAC.

18.
Cancers (Basel) ; 13(7)2021 Apr 06.
Article in English | MEDLINE | ID: mdl-33917420

ABSTRACT

Histone demethylases are epigenetic modulators that play key roles in regulating gene expression related to many critical cellular functions and are emerging as promising therapeutic targets in a number of tumor types. We previously identified histone demethylase family members as overexpressed in the pediatric sarcoma, rhabdomyosarcoma. Here we show high sensitivity of rhabdomyosarcoma cells to a pan-histone demethylase inhibitor, JIB-04 and identify a key role for the histone demethylase KDM4B in rhabdomyosarcoma cell growth through an RNAi-screening approach. Decreasing KDM4B levels affected cell cycle progression and transcription of G1/S and G2/M checkpoint genes including CDK6 and CCNA2, which are bound by KDM4B in their promoter regions. However, after sustained knockdown of KDM4B, rhabdomyosarcoma cell growth recovered. We show that this can be attributed to acquired molecular compensation via recruitment of KDM4A to the promoter regions of CDK6 and CCNA2 that are otherwise bound by KDM4B. Furthermore, upfront silencing of both KDM4B and KDM4A led to RMS cell apoptosis, not seen by reducing either alone. To circumvent compensation and elicit stronger therapeutic responses, our study supports targeting histone demethylase sub-family proteins through selective poly-pharmacology as a therapeutic approach.

19.
Front Oncol ; 9: 1078, 2019.
Article in English | MEDLINE | ID: mdl-31681608

ABSTRACT

Synovial Sarcomas (SS) are a type of Soft Tissue Sarcoma (STS) and represent 8-10% of all STS cases. Although SS can arise at any age, it typically affects younger individuals aged 15-35 and is therefore part of both pediatric and adult clinical practices. SS occurs primarily in the limbs, often near joints, but can present anywhere. It is characterized by the recurrent pathognomonic chromosomal translocation t(X;18)(p11.2;q11.2) that most frequently fuses SSX1 or SSX2 genes with SS18. This leads to the expression of the SS18-SSX fusion protein, which causes disturbances in several interacting multiprotein complexes such as the SWItch/Sucrose Non-Fermentable (SWI/SNF) complex, also known as the BAF complex and the Polycomb Repressive Complex 1 and 2 (PRC1 and PRC2). Furthermore, this promotes widespread epigenetic rewiring, leading to aberrant gene expression that drives the pathogenesis of SS. Good prognoses are characterized predominantly by small tumor size and young patient age. Whereas, high tumor grade and an increased genomic complexity of the tumor constitute poor prognostic factors. The current therapeutic strategy relies on chemotherapy and radiotherapy, the latter of which can lead to chronic side effects for pediatric patients. We will focus on the known roles of SWI/SNF, PRC1, and PRC2 as the main effectors of the SS18-SSX-mediated genome modifications and we present existing biological rationale for potential therapeutic targets and treatment strategies.

20.
Otol Neurotol ; 40(10): 1373-1377, 2019 12.
Article in English | MEDLINE | ID: mdl-31634280

ABSTRACT

OBJECTIVE: Determine whether elevated body mass index (BMI) is associated with postoperative complications after vestibular schwannoma (VS) surgery. STUDY DESIGN: Retrospective case series. SETTING: Tertiary referral center. PATIENTS: Two hundred six patients undergoing surgery for VS between 2010 and 2017, grouped into obese and nonobese patients. INTERVENTION: Surgery for VS resection. MAIN OUTCOME MEASURES: Postoperative facial nerve outcomes, length of hospital stay, presence of postoperative cerebrospinal fluid leak, 30-day readmission, return to the operating room, wound complications, cardiovascular and thromboembolic complications. RESULTS: After excluding 1 patient for missing BMI, our cohort included 205 patients. Seventy-nine patients (38.5%) were obese (mean BMI 36.2 kg/m, range 30-55.1) and the remaining 126 (61.5%) were nonobese (mean BMI 25.0, range 18.8-29.8 kg/m). Compared with nonobese patients, obesity was not associated with postoperative cerebrospinal fluid leak (OR 1.1, 95% CI 0.93-1.1), length of hospital stay (OR 0.98, 95% CI 0.65-1.47), 30-day readmission rates (1.04, 95% CI 0.95-1.14), return to operating room (OR 1.05, 95% CI 0.98-1.11), or other wound-related complications (OR 0.99, 95% CI 0.94-1.04). CONCLUSION: In this cohort, elevated BMI was not associated with an increased risk for postoperative complications after VS surgery. Our findings may mitigate concerns associated with surgical management of VS in obese patients.


Subject(s)
Neurilemmoma/surgery , Neuroma, Acoustic/surgery , Obesity/complications , Vestibular Diseases/surgery , Adult , Body Mass Index , Cerebrospinal Fluid Leak/complications , Cohort Studies , Female , Humans , Length of Stay , Male , Middle Aged , Neurilemmoma/complications , Neuroma, Acoustic/complications , Patient Readmission , Postoperative Complications/etiology , Postoperative Period , Retrospective Studies , Risk , Vestibular Diseases/complications
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