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2.
Nat Commun ; 15(1): 2333, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38485998

RESUMO

Antibiotic heteroresistance is a phenotype in which a susceptible bacterial population includes a small subpopulation of cells that are more resistant than the main population. Such resistance can arise by tandem amplification of DNA regions containing resistance genes that in single copy are not sufficient to confer resistance. However, tandem amplifications often carry fitness costs, manifested as reduced growth rates. Here, we investigated if and how these fitness costs can be genetically ameliorated. We evolved four clinical isolates of three bacterial species that show heteroresistance to tobramycin, gentamicin and tetracyclines at increasing antibiotic concentrations above the minimal inhibitory concentration (MIC) of the main susceptible population. This led to a rapid enrichment of resistant cells with up to an 80-fold increase in the resistance gene copy number, an increased MIC, and severely reduced growth rates. When further evolved in the presence of antibiotic, these strains acquired compensatory resistance mutations and showed a reduction in copy number while maintaining high-level resistance. A deterministic model indicated that the loss of amplified units was driven mainly by their fitness costs and that the compensatory mutations did not affect the loss rate of the gene amplifications. Our findings suggest that heteroresistance mediated by copy number changes can facilitate and precede the evolution towards stable resistance.


Assuntos
Antibacterianos , Tobramicina , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Bactérias/genética , Amplificação de Genes , Gentamicinas , Testes de Sensibilidade Microbiana , Farmacorresistência Bacteriana/genética
3.
Zhonghua Bing Li Xue Za Zhi ; 53(3): 237-242, 2024 Mar 08.
Artigo em Chinês | MEDLINE | ID: mdl-38433050

RESUMO

Objective: To investigate the diagnostic value of detecting MDM2 gene amplification by fluorescence in situ hybridization (FISH) in low-grade osteosarcoma (LGOS). Methods: Thirty cases of parosteal osteosarcoma (POS) and 14 cases of low-grade central osteosarcoma (LGCOS) from April 2009 to August 2022 at Beijing Jishuitan Hospital, Capital Medical University were analyzed for the presence of MDM2 gene amplification by FISH. Fifty-eight additional cases were used as negative controls (including 28 cases of fibrous dysplasia, 5 cases of giant cell tumor, 4 cases of conventional osteosarcoma, 2 cases each of periosteal osteosarcoma, reparative changes after fracture, pleomorphic undifferentiated sarcoma, low grade myofibroblastic sarcoma, fibrous dysplasia with malignant transformation, one case each of leiomyosarcoma, sclerosing epithelioid fibrosarcoma, malignant peripheral nerve sheath tumor, desmoplastic fibroma of bone, solitary fibrous tumor, aneurysmal bone cyst, clear cell chondrosarcoma, osteofibrous dysplasia, and 3 cases of unclassified spindle cell tumor). Results: Among the 30 patients with POS, 15 were male and 15 were female, ranging in age from 10 to 59 years (mean 35 years, median 30.5 years). Among the 14 patients with LGCOS, four were male and 10 were female, ranging in age from 15 to 56 years (mean 37 years, median 36 years). All except one case were successfully detected by FISH. MDM2 gene amplification was detected in 27 cases of POS (27/29,91.3%) and 8 cases of LGCOS (8/14). All the negative controls were negative for MDM2 gene amplification. The positive rate of MDM2 gene amplification was significantly different between the case group and the control group (P<0.05). The sensitivity and specificity of MDM2 gene amplification in diagnosing POS and LGCOS were 91.3% and 100.0%; and 57.1% and 100.0%, respectively. The sensitivity and specificity of MDM2 gene amplification in diagnosing LGOS (including POS and LGCOS) were 81.3% and 100.0%, respectively. In cases where MDM2 gene was amplified, the MDM2 amplified signal was clustered. Nine cases showed increased CEP12 signal different from polyploidy which was displayed as small and weak signal points or cloud flocculent and cluster signals. Conclusions: Detection of MDM2 gene amplification by FISH is a highly sensitive and specific marker for LGOS. The interpretation criteria for FISH detection of MDM2 amplification are currently not unified. The signal characteristics need more attention when interpreting.


Assuntos
Neoplasias Ósseas , Fibrossarcoma , Osteossarcoma , Sarcoma , Humanos , Feminino , Masculino , Criança , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Amplificação de Genes , Hibridização in Situ Fluorescente , Osteossarcoma/diagnóstico , Osteossarcoma/genética , Neoplasias Ósseas/diagnóstico , Neoplasias Ósseas/genética , Proteínas Proto-Oncogênicas c-mdm2/genética
4.
Int J Mol Sci ; 25(5)2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38473941

RESUMO

The PIK3CA and SOX2 genes map at 3q26, a chromosomal region frequently amplified in head and neck cancers, which is associated with poor prognosis. This study explores the clinical significance of PIK3CA and SOX2 gene amplification in early tumorigenesis. Gene copy number was analyzed by real-time PCR in 62 laryngeal precancerous lesions and correlated with histopathological grading and laryngeal cancer risk. Amplification of the SOX2 and PIK3CA genes was frequently detected in 19 (31%) and 32 (52%) laryngeal dysplasias, respectively, and co-amplification in 18 (29%) cases. The PIK3CA and SOX2 amplifications were predominant in high-grade dysplasias and significantly associated with laryngeal cancer risk beyond histological criteria. Multivariable Cox analysis further revealed PIK3CA gene amplification as an independent predictor of laryngeal cancer development. Interestingly, combined PIK3CA and SOX2 amplification allowed us to distinguish three cancer risk subgroups, and PIK3CA and SOX2 co-amplification was found the strongest predictor by ROC analysis. Our data demonstrate the clinical relevance of PIK3CA and SOX2 amplification in early laryngeal tumorigenesis. Remarkably, PIK3CA amplification was found to be an independent cancer predictor. Furthermore, combined PIK3CA and SOX2 amplification is emerging as a valuable and easy-to-implement tool for cancer risk assessment in patients with laryngeal precancerous lesions beyond current WHO histological grading.


Assuntos
Neoplasias Laríngeas , Lesões Pré-Cancerosas , Humanos , Amplificação de Genes , Neoplasias Laríngeas/genética , Lesões Pré-Cancerosas/genética , Classe I de Fosfatidilinositol 3-Quinases/genética , Carcinogênese/genética , Fatores de Transcrição SOXB1/genética
5.
Mod Pathol ; 37(4): 100451, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38369190

RESUMO

MET amplification (METamp) represents a promising therapeutic target in non-small cell lung cancer, but no consensus has been established to identify METamp-dependent tumors that could potentially benefit from MET inhibitors. In this study, an analysis of MET amplification/overexpression status was performed in a retrospectively recruited cohort comprising 231 patients with non-small cell lung cancer from Shanghai Chest Hospital (SCH cohort) using 3 methods: fluorescence in situ hybridization (FISH), hybrid capture-based next-generation sequencing, and immunohistochemistry for c-MET and phospho-MET. The SCH cohort included 130 cases known to be METamp positive by FISH and 101 negative controls. The clinical relevance of these approaches in predicting the efficacy of MET inhibitors was evaluated. Additionally, next-generation sequencing data from another 2 cohorts including 22,010 lung cancer cases were utilized to examine the biological characteristics of different METamp subtypes. Of the 231 cases, 145 showed MET amplification/overexpression using at least 1 method, whereas only half of them could be identified by all 3 methods. METamp can occur as focal amplification or polysomy. Our study revealed that the inconsistency between next-generation sequencing and FISH primarily occurred in the polysomy subtype. Further investigations indicated that compared with polysomy, focal amplification correlated with fewer co-occurring driver mutations, higher protein expressions of c-MET and phospho-MET, and higher incidence in acquired resistance than in de novo setting. Moreover, patients with focal amplification presented a more robust response to MET inhibitors compared with those with polysomy. Notably, a strong correlation was observed between focal amplification and programmed cell death ligand-1 expression, indicating potential therapeutic implications with combined MET inhibitor and immunotherapy for patients with both alterations. Our findings provide insights into the molecular complexity and clinical relevance of METamp in lung cancer, highlighting the role of MET focal amplification as an oncogenic driver and its feasibility as a primary biomarker to further investigate the clinical activity of MET inhibitors in future studies.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Neoplasias Pulmonares/patologia , Carcinoma Pulmonar de Células não Pequenas/genética , Estudos Retrospectivos , Hibridização in Situ Fluorescente , Mutação , China , Proteínas Proto-Oncogênicas c-met/genética , Proteínas Proto-Oncogênicas c-met/metabolismo , Aberrações Cromossômicas , Amplificação de Genes
6.
Hum Pathol ; 145: 56-62, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38401716

RESUMO

Several high-grade pleomorphic sarcoma cases that cannot be classified into any existing established categories have been reported. These cases were provisionally classified into undifferentiated pleomorphic sarcoma (UPS). Some dedifferentiated liposarcoma (DDLS) cases may also have been classified into the UPS category due to the absence of MDM2 amplification or an atypical lipomatous tumor/well-differentiated liposarcoma component. We retrieved and reviewed 77 high-grade pleomorphic sarcoma cases, initially diagnosed as UPS in 66 cases and DDLS in 11 cases. Fluorescence in situ hybridization (FISH) analyses of DDIT3 and MDM2 were performed for available cases. Of the cases successfully subjected to DDIT3 FISH (n = 56), nine (7 UPS and 2 DDLS) showed DDIT3 amplification but no MDM2 amplification. Two UPS cases showed both telomeric (5') and centromeric (3') amplification of DDIT3 or low polysomy of chromosome 12, whereas 5 UPS and 2 DDLS cases showed 5'-predominant DDIT3 amplification. Histopathologically, all cases showed UPS-like proliferation of atypical pleomorphic tumor cells. Immunohistochemically, only one case showed focal nuclear positivity for DDIT3, supporting the previous finding that DDIT3 expression was not correlated with DDIT3 amplification. All three cases with focal MDM2 expression involved 5'-predominant amplification, two of which showed DDLS-like histological features. The majority of cases (7/9) showed decreased expression in p53 staining, suggesting that DDIT3 amplification regulates the expression of TP53 like MDM2. From a clinicopathological perspective, we hypothesize that DDIT3-amplified sarcoma, especially with 5'-predominant amplification, can be reclassified out of the UPS category.


Assuntos
Histiocitoma Fibroso Maligno , Lipoma , Lipossarcoma , Sarcoma , Neoplasias de Tecidos Moles , Humanos , Lipossarcoma/patologia , Hibridização in Situ Fluorescente , Amplificação de Genes , Sarcoma/genética , Sarcoma/patologia , Lipoma/diagnóstico , Aberrações Cromossômicas , Neoplasias de Tecidos Moles/diagnóstico , Fator de Transcrição CHOP/genética , Fator de Transcrição CHOP/metabolismo , Proteínas Proto-Oncogênicas c-mdm2/análise
7.
Clin Cancer Res ; 30(8): 1669-1684, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38345769

RESUMO

PURPOSE: ERBB2-amplified colorectal cancer is a distinct molecular subtype with expanding treatments. Implications of concurrent oncogenic RAS/RAF alterations are not known. EXPERIMENTAL DESIGN: Dana-Farber and Foundation Medicine Inc. Colorectal cancer cohorts with genomic profiling were used to identify ERBB2-amplified cases [Dana-Farber, n = 47/2,729 (1.7%); FMI, n = 1857/49,839 (3.7%)]. Outcomes of patients receiving HER2-directed therapies are reported (Dana-Farber, n = 9; Flatiron Health-Foundation Medicine clinicogenomic database, FH-FMI CGDB, n = 38). Multisite HER2 IHC and genomic profiling were performed to understand HER2 intratumoral and interlesional heterogeneity. The impact of concurrent RAS comutations on the effectiveness of HER2-directed therapies were studied in isogenic colorectal cancer cell lines and xenografts. RESULTS: ERBB2 amplifications are enriched in left-sided colorectal cancer. Twenty percent of ERBB2-amplified colorectal cancers have co-occurring oncogenic RAS/RAF alterations. While RAS/RAF WT colorectal cancers typically have clonal ERBB2 amplification, colorectal cancers with co-occurring RAS/RAF alterations have lower level ERRB2 amplification, higher intratumoral heterogeneity, and interlesional ERBB2 discordance. These distinct genomic patterns lead to differential responsiveness and patterns of resistance to HER2-directed therapy. ERBB2-amplified colorectal cancer with RAS/RAF alterations are resistant to trastuzumab-based combinations, such as trastuzumab/tucatinib, but retain sensitivity to trastuzumab deruxtecan in in vitro and murine models. Trastuzumab deruxtecan shows clinical efficacy in cases with high-level ERBB2-amplified RAS/RAF coaltered colorectal cancer. CONCLUSIONS: Co-occurring RAS/RAF alterations define a unique subtype of ERBB2-amplified colorectal cancer that has increased intratumoral heterogeneity, interlesional discordance, and resistance to trastuzumab-based combinations. Further examination of trastuzumab deruxtecan in this previously understudied cohort of ERBB2-amplified colorectal cancer is warranted.


Assuntos
Neoplasias Colorretais , Variações do Número de Cópias de DNA , Humanos , Animais , Camundongos , Amplificação de Genes , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Receptor ErbB-2/metabolismo , Trastuzumab/farmacologia , Trastuzumab/uso terapêutico , Resultado do Tratamento , Mutação
8.
Cell Cycle ; 23(1): 36-42, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38350028

RESUMO

Copy number variation (CNV) of certain genes in pediatric Acute Lymphoblastic Leukemia (ALL) impacts gene expression levels. Here, we aimed to investigate the potential prognostic utility of CNVs in pediatric B-ALL and T-ALL. Using genomics files representing cases from the TARGET-ALL-P2 dataset, genes commonly involved in ALL development were analyzed for CNVs. Case IDs representing increased copy numbers for SOX11, PDGFRB, and MDK represented a worse overall survival probability specifically for B-ALL (logrank p=0.021, p=0.0052, p=0.019, respectively). These data support the continued investigation of using CNVs for clinical prognostic biomarkers for pediatric B-ALL.


Assuntos
Amplificação de Genes , Leucemia-Linfoma Linfoblástico de Células Precursoras , Criança , Humanos , Variações do Número de Cópias de DNA/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Genômica , Fatores de Transcrição SOXC/genética
9.
Sci Rep ; 14(1): 3034, 2024 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-38321088

RESUMO

The chromosome 20 long arm (20q) is one of the genomic hotspots where copy number alterations frequently occur in multiple types of tumors. However, it remains elusive which genes are implicated in 20q-related tumorigenesis. Here, by querying TCGA and GEO databases, we observed frequent copy number amplification at 20q and the chromosome subband 20q13.33 was amplificated in multiple cancers. Among those genes at 20q13.33, PSMA7 was found with the strongest correlation with cancers. Further analysis revealed that PSMA7 amplification was the most frequent genetic alteration event conferring adverse prognosis in various cancers. Consistent with the strong positive correlation between PSMA7 amplification and gene expression, elevated PSMA7 expression was observed in 20 of 33 types of cancers with a close link to adverse outcomes in certain tumors. In addition, PSMA7 was essential for the growth of almost 1095 cancer lines. Mechanistically, aberrant PSMA7 most probably influenced the proteasome and protease-related pathways to promote tumorigenesis and might be antagonized by several compounds, e.g., Docetaxel in relevant cancers. The current in-depth pan-cancer analysis refines our understanding of the crucial oncogenic role of copy number amplifications at PSMA7 loci at the novel chromosome amplicon 20q13.33 across different tumors.


Assuntos
Transformação Celular Neoplásica , Genoma , Humanos , Transformação Celular Neoplásica/genética , Variações do Número de Cópias de DNA , Prognóstico , Cromossomos/metabolismo , Amplificação de Genes , Complexo de Endopeptidases do Proteassoma/metabolismo
10.
Diagn Pathol ; 19(1): 32, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38360676

RESUMO

BACKGROUND: Accurate quantification of human epidermal growth factor receptor 2 (HER2) gene amplification is important for predicting treatment response and prognosis in patients with breast cancer. Fluorescence in situ hybridization (FISH) is the gold standard for the diagnosis of HER2 status, particularly in cases with equivocal status on immunohistochemistry (IHC) staining, but has some limitations of non-classical amplifications and such cases are diagnosed basing on additional IHC and FISH. This study investigated the clinical utility of a novel super-resolution fluorescence microscopy technique for the better FISH signal visualization and HER2 FISH classification. METHODS: Fourteen breast cancer tissue samples were retrospectively collected between September 2018 and February 2022, and FISH HER2 signal quantification was evaluated by determining the HER2/chromosome 17 centromere (CEP17) ratio and the number of HER2 signals per nucleus in super- versus conventional-resolution images. RESULTS: Super-resolution images maintained the same overall HER2 diagnosis from routine, but HER2 FISH amplification changed negative to monosomy in two cases. Two Letrozole non-response relapses coincided to monosomy samples. The median number of HER2 signals per nucleus was 7.5 in super-resolution images and 4.0 in conventional-resolution images in HER2-positive samples and 2.8 and 2.1 signals per nucleus, respectively, in HER2-negative samples. CONCLUSIONS: Super-resolution images improved signal visualization, including a significant difference in the number of countable HER2 and CEP17 signals in a single nucleus compared with conventional-resolution images. Increased accuracy of signal quantification by super-resolution microscopy may provide clinicians with more detailed information regarding HER2 FISH status that allows to better FISH classification such as HER2-low samples.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/diagnóstico , Hibridização in Situ Fluorescente/métodos , Estudos Retrospectivos , Recidiva Local de Neoplasia/genética , Receptor ErbB-2/genética , Receptor ErbB-2/metabolismo , Monossomia , Amplificação de Genes
11.
Pathology ; 56(3): 325-333, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38195375

RESUMO

The frequency of MET and HER2 amplification being detected by next generation sequencing (NGS) is increasing due to NGS being increasingly adopted for molecular profiling of cancers. However, the accuracy of NGS in detecting these gene amplifications remains uncertain due to conflicting reports in the scientific literature. We studied the accuracy of an amplicon-based large panel NGS assay in detecting MET and HER2 amplification in lung and breast cancers, respectively, by comparing it against conventional testing methods. Amongst 48 lung cancers, four of five cancers that were MET amplified on fluorescence in situ hybridisation (FISH) were classified as amplified on NGS while 42 of the remaining 43 non-amplified cancers were classified as non-amplified on NGS, giving a sensitivity of 80%, specificity of 97.7% and overall concordance of 95.8%. Of the 46 breast cancers tested, only six of the nine cancers that were HER2-positive on immunohistochemistry (IHC)/FISH were HER2-positive on NGS, while all the remaining HER2-negative cases were negative on NGS, giving a sensitivity of 66.7%, specificity of 100% and overall concordance of 93.5%. All the false-negative cases had low level gene amplification (MET:CEP7 or HER2:CEP17 FISH ratio of <3). The low sensitivity for HER2 amplification may be confounded by the small sample size and disproportionate number of cases with low level amplification. In summary, the NGS assay has good concordance with conventional testing methods but may be less sensitive in detecting low level gene amplification.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/genética , Receptor ErbB-2/genética , Receptor ErbB-2/metabolismo , Sequenciamento de Nucleotídeos em Larga Escala , Amplificação de Genes , Pulmão/metabolismo
12.
Arch Pathol Lab Med ; 148(2): 242-255, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-37014972

RESUMO

CONTEXT.­: Human epidermal growth factor receptor 2 (HER2) status in breast cancer is currently classified as negative or positive for selecting patients for anti-HER2 targeted therapy. The evolution of the HER2 status has included a new HER2-low category defined as an HER2 immunohistochemistry score of 1+ or 2+ without gene amplification. This new category opens the door to a targetable HER2-low breast cancer population for which new treatments may be effective. OBJECTIVE.­: To review the current literature on the emerging category of breast cancers with low HER2 protein expression, including the clinical, histopathologic, and molecular features, and outline the clinical trials and best practice recommendations for identifying HER2-low-expressing breast cancers by immunohistochemistry. DATA SOURCES.­: We conducted a literature review based on peer-reviewed original articles, review articles, regulatory communications, ongoing and past clinical trials identified through ClinicalTrials.gov, and the authors' practice experience. CONCLUSIONS.­: The availability of new targeted therapy potentially effective for patients with breast cancers with low HER2 protein expression requires multidisciplinary recognition. In particular, pathologists need to recognize and identify this category to allow the optimal selection of patients for targeted therapy.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Hibridização in Situ Fluorescente , Receptor ErbB-2/genética , Receptor ErbB-2/metabolismo , Amplificação de Genes , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo
13.
Clin Cancer Res ; 30(4): 649-651, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38064245

RESUMO

Dedifferentiated liposarcoma (DDLPS) has an appealing therapeutic target due to its CDK4 amplification on chromosome 12q. The understanding of geroconversion from quiescent cells to senescent cells defines a patient's response to CDK4 inhibitors. This new observation will inform not only the ongoing phase III clinical trial of abemaciclib, but all future clinical trials in DDLPS. See related article by Gleason et al., p. 703.


Assuntos
Lipossarcoma , Humanos , Lipossarcoma/tratamento farmacológico , Lipossarcoma/genética , Proteínas Proto-Oncogênicas c-mdm2/genética , Quinase 4 Dependente de Ciclina/genética , Quinase 4 Dependente de Ciclina/metabolismo , Amplificação de Genes
14.
Talanta ; 269: 125444, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38042143

RESUMO

Signal transduction mediated by epidermal growth factor receptor (EGFR) gene affects the proliferation, invasion, metastasis, and angiogenesis of tumor cells. In particular, non-small cell lung cancer (NSCLC) patients with increased in copy number of EGFR gene are often sensitive to tyrosine kinase inhibitors. Despite being the standard for detecting EGFR amplification in the clinic, fluorescence in situ hybridization (FISH) traditionally involves repetitive and complex benchtop procedures that are not only time consuming but also require well-trained personnel. To address these limitations, we develop a digital microfluidics-based FISH platform (DMF-FISH) that automatically implements FISH operations. This system mainly consists of a DMF chip for reagent operation, a heating array for temperature control and a signal processing system. With the capability of automatic droplet handling and efficient temperature control, DMF-FISH performs cell digestion, gradient elution, hybridization and DAPI staining without manual intervention. In addition to operational feasibility, DMF-FISH yields comparable performance with the benchtop FISH protocol but reducing the consumption of DNA probe by 87 % when tested with cell lines and clinical samples. These results highlight unique advantages of the fully automated DMF-FISH system and thus suggest its great potential for clinical diagnosis and personalized therapy of NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/patologia , Amplificação de Genes , Receptores ErbB/genética , Receptores ErbB/metabolismo , Hibridização in Situ Fluorescente/métodos , Microfluídica , Dosagem de Genes , Mutação
15.
Genes Chromosomes Cancer ; 63(1): e23214, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38050922

RESUMO

Gene amplification is a crucial process in cancer development, leading to the overexpression of oncogenes. It manifests cytogenetically as extrachromosomal double minutes (dmin), homogeneously staining regions (hsr), or ring chromosomes (r). This study investigates the prevalence and distribution of these amplification markers in a survey of 80 131 neoplasms spanning hematologic disorders, and benign and malignant solid tumors. The study reveals distinct variations in the frequency of dmin, hsr, and r among different tumor types. Rings were the most common (3.4%) sign of amplification, followed by dmin (1.3%), and hsr (0.8%). Rings were particularly frequent in malignant mesenchymal tumors, especially liposarcomas (47.5%) and osteosarcomas (23.4%), dmin were prevalent in neuroblastoma (30.9%) and pancreatic carcinoma (21.9%), and hsr frequencies were highest in head and neck carcinoma (14.0%) and neuroblastoma (9.0%). Combining all three amplification markers (dmin/hsr/r), malignant solid tumors consistently exhibited higher frequencies than hematologic disorders and benign solid tumors. The structural characteristics of these amplification markers and their potential role in tumorigenesis and tumor progression highlight the complex interplay between cancer-initiating gene-level alterations, for example, fusion genes, and subsequent amplification dynamics. Further research integrating cytogenetic and molecular approaches is warranted to better understand the underlying mechanisms of these amplifications, in particular, the enigmatic question of why certain malignancies display certain types of amplification. Comparing the present results with molecular genetic data proved challenging because of the diversity in definitions of amplification across studies. This study underscores the need for standardized definitions in future work.


Assuntos
Neoplasias Ósseas , Neuroblastoma , Sarcoma , Humanos , Amplificação de Genes , Sarcoma/genética , Aberrações Cromossômicas , Neuroblastoma/genética , Neoplasias Ósseas/genética , Análise Citogenética
16.
Gynecol Oncol ; 180: 1-5, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38029652

RESUMO

OBJECTIVE: Investigate the prevalence of ERBB2/HER2 gene amplification among patients with gynecologic malignancies. METHODS: The American Association of Cancer Research (AACR) Genomics Evidence of Neoplasia Information Exchange (GENIE) (version 13.1) database was accessed and patients with endometrial, ovarian, and cervical cancer were identified. Patients with available data on the presence of copy-number gene alterations were selected for further analysis. Incidence of ERBB2 amplification following stratification by tumor site and histology was evaluated. Data from the OncoKB database, as provided by cBioPortal, was utilized to determine presence of pathogenic genomic alterations. RESULTS: A total of 6961 patients who met the inclusion criteria were identified: 49.1% with ovarian cancer, 45.2% with endometrial cancer and 5.7% with cervical cancer respectively. Overall incidence of ERBB2 amplification was 3.8%. Highest incidence of ERBB2 amplification was observed among patients with mucinous ovarian (14.4%), uterine serous (13.2%), uterine clear cell (9.4%), and uterine carcinosarcoma (7.9%). ERBB2 amplification was rare among patients with TP53 wild-type endometrioid endometrial cancer (0.4%). High incidence of mutations in genes of the PI3K pathway was observed among patients with ERBB2 amplified tumors. CONCLUSION: ERBB2 amplification is frequently encountered among patients with uterine serous carcinoma, and mucinous ovarian carcinoma. In addition, a high incidence was also observed among those with uterine clear cell carcinoma, and uterine carcinosarcoma. For patients with endometrioid endometrial carcinoma, incidence of ERBB2 amplification is low, especially in the absence of TP53 mutations.


Assuntos
Carcinoma Endometrioide , Carcinossarcoma , Neoplasias do Endométrio , Neoplasias dos Genitais Femininos , Neoplasias Ovarianas , Neoplasias do Colo do Útero , Neoplasias Uterinas , Humanos , Feminino , Neoplasias dos Genitais Femininos/genética , Amplificação de Genes , Neoplasias do Colo do Útero/genética , Fosfatidilinositol 3-Quinases/metabolismo , Mutação , Neoplasias Ovarianas/patologia , Neoplasias Uterinas/genética , Neoplasias do Endométrio/genética , Neoplasias do Endométrio/patologia , Carcinoma Endometrioide/patologia , Carcinossarcoma/patologia , Receptor ErbB-2/genética , Receptor ErbB-2/metabolismo
17.
J Pathol ; 262(2): 129-136, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38013631

RESUMO

Trastuzumab has demonstrated clinical efficacy in the treatment of HER2-positive serous endometrial cancer (EC), which led to its incorporation into standard-of-care management of this aggressive disease. Acquired resistance remains an important challenge, however, and its underlying mechanisms in EC are unknown. To define the molecular changes that occur in response to anti-HER2 therapy in EC, targeted next-generation sequencing (NGS), HER2 immunohistochemistry (IHC), and fluorescence in situ hybridization (FISH) were performed on pre- and post-treatment tumour samples from 14 patients with EC treated with trastuzumab or trastuzumab emtansine. Recurrent tumours after anti-HER2 therapy acquired additional genetic alterations compared with matched pre-treatment ECs and frequently showed decreased HER2 protein expression by IHC (7/14, 50%). Complete/near-complete absence of HER2 protein expression (score 0/1+) observed post-treatment (4/14, 29%) was associated with retained HER2 gene amplification (n = 3) or copy number neutral status (n = 1). Whole-exome sequencing performed on primary and recurrent tumours from the latter case, which exhibited genetic heterogeneity of HER2 amplification in the primary tumour, revealed selection of an early HER2-non-amplified clone following therapy. Our findings demonstrate that loss of target expression, by selection of HER2-non-amplified clones or, more commonly, by downregulation of expression, may constitute a mechanism of resistance to anti-HER2 therapy in HER2-positive EC. © 2023 The Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.


Assuntos
Neoplasias do Endométrio , Receptor ErbB-2 , Feminino , Humanos , Receptor ErbB-2/genética , Receptor ErbB-2/metabolismo , Hibridização in Situ Fluorescente , Recidiva Local de Neoplasia/genética , Trastuzumab/uso terapêutico , Neoplasias do Endométrio/tratamento farmacológico , Neoplasias do Endométrio/genética , Neoplasias do Endométrio/patologia , Amplificação de Genes
18.
J Surg Oncol ; 129(2): 219-223, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37850570

RESUMO

BACKGROUND: Neuroblastomas rarely occur as primary tumors in the cervical region. Therefore, very little has been reported regarding treatment strategies, complications, and outcomes of these cervical neuroblastomas. The goal of this study is to review the presentation, management, and outcomes of all primary cervical pediatric neuroblastoma cases at a single tertiary care center. METHODS: A retrospective cohort review of all neuroblastoma patients treated at a single center were performed. All patients with primary cervical neuroblastoma were reviewed for demographic information, tumor characteristics, treatment, and outcomes. RESULTS: Thirty (1.8%) patients were found to have undergone treatment for cervical neuroblastoma tumors diagnosed on average at 2.1 years old. Most presented with a swollen neck/palpable mass ± Horner's syndrome. Based on features including tumor staging, N-myc proto-oncogene protein (MYCN) amplification status, histology, most were deemed intermediate or high risk. Treatment strategies centered around chemotherapeutic regimens with surgery when possible as well as various adjuvant treatments including radiation therapy, immunotherapy, bone marrow transplant, and a neuroblastoma vaccine. Ten (33.3%) of patients experienced treatment-related complications and four (13.3%) died as a result of their disease progression. All four patients were high-risk patients, two of which had MYCN amplification. CONCLUSION: Cervical neuroblastomas generally have favorable outcomes. These tumors can be treated effectively with chemotherapy and surgical intervention with various adjuvant therapies. MYCN amplification and higher stage disease presentation contribute to worse outcomes.


Assuntos
Neuroblastoma , Criança , Humanos , Lactente , Pré-Escolar , Proteína Proto-Oncogênica N-Myc/uso terapêutico , Estudos Retrospectivos , Análise de Sobrevida , Estadiamento de Neoplasias , Neuroblastoma/tratamento farmacológico , Neuroblastoma/genética , Amplificação de Genes
19.
Mol Cancer Res ; 22(2): 152-168, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-37930255

RESUMO

11q13 amplification is a frequent event in human cancer and in particular in squamous cell carcinomas (SCC). Despite almost invariably spanning 10 genes, it is unclear which genetic components of the amplicon are the key driver events in SCC. A combination of computational, in vitro, ex vivo, and in vivo models leveraging efficient primary human keratinocyte genome editing by Cas9-RNP electroporation, identified ORAOV1, CCND1, and MIR548K as the critical drivers of the amplicon in head and neck SCC. CCND1 amplification drives the cell cycle in a CDK4/6/RB1-independent fashion and may confer a novel dependency on RRM2. MIR548K contributes to epithelial-mesenchymal transition. Finally, we identify ORAOV1 as an oncogene that acts likely via its ability to modulate reactive oxygen species. Thus, the 11q13 amplicon drives SCC through at least three independent genetic elements and suggests therapeutic targets for this morbid and lethal disease. IMPLICATIONS: This work demonstrates novel mechanisms and ways to target these mechanisms underlying the most common amplification in squamous cell carcinoma, one of the most prevalent and deadly forms of human cancer.


Assuntos
Carcinoma de Células Escamosas , Humanos , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patologia , Ciclo Celular , Linhagem Celular Tumoral , Ciclina D1/genética , Amplificação de Genes , Oncogenes/genética
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