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1.
Cancers (Basel) ; 15(20)2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37894318

RESUMO

Extra-pulmonary poorly differentiated neuroendocrine carcinoma is rare, and evidence for treatment has been limited. In this article, the evidence behind the cytotoxic chemotherapy choices used for metastatic or unresectable EP-PD-NEC is reviewed. In the first-line setting, etoposide and platinum chemotherapy or irinotecan and platinum have been demonstrated to be equivalent in a large phase III trial. Questions remain regarding the optimal number of cycles, mode of delivery, and the precise definition of platinum resistance in this setting. In the second-line setting, FOLFIRI has emerged as an option, with randomized phase 2 trials demonstrating modest, but significant, response rates. Beyond this, data are extremely limited, and several regimens have been used. Heterogeneity in biological behaviour is a major barrier to optimal EP-PD-NEC management. Available data support the potential role of the Ki-67 index as a predictive biomarker for chemotherapy response. A more personalised approach to management in future studies will be essential, and comprehensive multi-omic approaches are required to understand tumour somatic genetic changes in relation to their effects on the surrounding microenvironment.

2.
QJM ; 116(4): 285-287, 2023 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-36377790

RESUMO

OBJECTIVE: To determine the proportion of emergency patients treated with immune checkpoint inhibitors (ICIs) that require critical care admission and their requirements. DESIGN: Prospective case series. METHODS: Analysis of acutely unwell patients treated with ICIs attending a tertiary UK cancer hospital between May 2018 and May 2022. The primary outcome measure was the percentage of patients treated with ICI therapy requiring ICU admission. The secondary outcome measure was whether this need was driven by an immune-mediated toxicity. RESULTS: Eighteen (1.2%) patients of the 1561 acutely admitted patients treated with ICI therapy required an admission to ICU. Ten (55.5%) patients were admitted due to an immune-mediated toxicity; four due to pneumonitis and four due to myasthenia gravis. Seven of 10 survived their ICU admission with 6 surviving at least 6-month post-ICU discharge. CONCLUSIONS: Only a small minority of emergency admissions in patients treated with ICIs require admission to ICU. This series adds further evidence that patients with organ failure due to immune-mediated toxicity may achieve good outcomes from ICU admission.


Assuntos
Inibidores de Checkpoint Imunológico , Miastenia Gravis , Humanos , Inibidores de Checkpoint Imunológico/efeitos adversos , Unidades de Terapia Intensiva , Hospitalização , Cuidados Críticos , Estudos Retrospectivos
3.
BMC Genomics ; 23(1): 599, 2022 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-35978291

RESUMO

BACKGROUND: Somatic copy number alterations (SCNAs) are an important class of genomic alteration in cancer. They are frequently observed in cancer samples, with studies showing that, on average, SCNAs affect 34% of a cancer cell's genome. Furthermore, SCNAs have been shown to be major drivers of tumour development and have been associated with response to therapy and prognosis. Large-scale cancer genome studies suggest that tumours are driven by somatic copy number alterations (SCNAs) or single-nucleotide variants (SNVs). Despite the frequency of SCNAs and their clinical relevance, the use of genomics assays in the clinic is biased towards targeted gene panels, which identify SNVs but provide limited scope to detect SCNAs throughout the genome. There is a need for a comparably low-cost and simple method for high-resolution SCNA profiling. RESULTS: We present conliga, a fully probabilistic method that infers SCNA profiles from a low-cost, simple, and clinically-relevant assay (FAST-SeqS). When applied to 11 high-purity oesophageal adenocarcinoma samples, we obtain good agreement (Spearman's rank correlation coefficient, rs=0.94) between conliga's inferred SCNA profiles using FAST-SeqS data (approximately £14 per sample) and those inferred by ASCAT using high-coverage WGS (gold-standard). We find that conliga outperforms CNVkit (rs=0.89), also applied to FAST-SeqS data, and is comparable to QDNAseq (rs=0.96) applied to low-coverage WGS, which is approximately four-fold more expensive, more laborious and less clinically-relevant. By performing an in silico dilution series experiment, we find that conliga is particularly suited to detecting SCNAs in low tumour purity samples. At two million reads per sample, conliga is able to detect SCNAs in all nine samples at 3% tumour purity and as low as 0.5% purity in one sample. Crucially, we show that conliga's hidden state information can be used to decide when a sample is abnormal or normal, whereas CNVkit and QDNAseq cannot provide this critical information. CONCLUSIONS: We show that conliga provides high-resolution SCNA profiles using a convenient, low-cost assay. We believe conliga makes FAST-SeqS a more clinically valuable assay as well as a useful research tool, enabling inexpensive and fast copy number profiling of pre-malignant and cancer samples.


Assuntos
Variações do Número de Cópias de DNA , Neoplasias , Sequência de Bases , DNA , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Neoplasias/genética
4.
Commun Biol ; 5(1): 335, 2022 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-35396535

RESUMO

Oesophageal adenocarcinoma (OAC) provides an ideal case study to characterize large-scale rearrangements. Using whole genome short-read sequencing of 383 cases, for which 214 had matched whole transcriptomes, we observed structural variations (SV) with a predominance of deletions, tandem duplications and inter-chromosome junctions that could be identified as LINE-1 mobile element (ME) insertions. Complex clusters of rearrangements resembling breakage-fusion-bridge cycles or extrachromosomal circular DNA accounted for 22% of complex SVs affecting known oncogenes. Counting SV events affecting known driver genes substantially increased the recurrence rates of these drivers. After excluding fragile sites, we identified 51 candidate new drivers in genomic regions disrupted by SVs, including ETV5, KAT6B and CLTC. RUNX1 was the most recurrently altered gene (24%), with many deletions inactivating the RUNT domain but preserved the reading frame, suggesting an altered protein product. These findings underscore the importance of identification of SV events in OAC with implications for targeted therapies.


Assuntos
Adenocarcinoma , Neoplasias Esofágicas , Adenocarcinoma/genética , Neoplasias Esofágicas/genética , Genoma Humano , Histona Acetiltransferases/genética , Humanos , Sequenciamento Completo do Genoma
5.
PLoS One ; 14(11): e0224540, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31774822

RESUMO

Cancer cachexia is common in patients with oesophagogastric cancer (OG) and is linked to overall survival (OS). One of the key components of cachexia is anorexia; it is not known whether anorexia impacts on OS and there is no method of routine screening in current practice. Diagnosis relies on patients describing the symptoms, clinicians diagnosing anorexia and acting upon it. Patients with oesophageal/gastroesophageal junction or gastric cancer were assessed using the Functional Assessment of Anorexia Cachexia Therapy Anorexia/Cachexia Subscale (FAACT A/CS). FAACT A/CS includes 12 questions validated previously to diagnose anorexia in patients with cancer. Of the 182 patients included, 69% scored ≤37/48 and were considered to be anorexic; FAACT A/CS was a better predictor of OS in metastatic patients than body mass index or weight loss in the six months prior to cancer diagnosis. The median OS of patients with FAACT A/CS scores of >37 was longer than patients with scores of ≤37 (19.3 months vs 6.7 months, Hazard Ratio [HR] 2.9, 95% Confidence Interval [CI] 1.4-6.0, p<0.0001). Patients with performance status (PS) 0-2 and FAACT A/CS >37 had substantially longer OS than those with PS 0-2 and FAACT A/CS ≤37 (18.7 months vs 7.9 months, HR 2.5 (95% CI 1.2-5.1, P<0.0001). The FAACT A/CS questionnaire allows clinicians to identify patients with anorexia who may benefit from early nutrition interventions. Importantly, this is the first study to show the association between anorexia and survival in patients with metastatic OG cancers. This will form the basis of future interventional studies to improve patient outcomes.


Assuntos
Adenocarcinoma/mortalidade , Anorexia/diagnóstico , Neoplasias Esofágicas/mortalidade , Junção Esofagogástrica/patologia , Avaliação Nutricional , Neoplasias Gástricas/mortalidade , Adenocarcinoma/complicações , Adenocarcinoma/patologia , Idoso , Idoso de 80 Anos ou mais , Anorexia/etiologia , Anorexia/mortalidade , Índice de Massa Corporal , Neoplasias Esofágicas/complicações , Neoplasias Esofágicas/patologia , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Qualidade de Vida , Autorrelato , Neoplasias Gástricas/complicações , Neoplasias Gástricas/patologia
6.
J Gastrointest Surg ; 23(9): 1729-1741, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-30671799

RESUMO

PURPOSE: The aim of this cohort study was to assess the benefit that patients with lower esophageal or gastroesophageal junction (E/GEJ) adenocarcinoma receive by continuing perioperative chemotherapy post-surgery. METHODS: Three hundred twelve patients underwent radical tumor surgical resection after preoperative chemotherapy. Chemotherapy was mainly ECX (epirubicin, cisplatin, capecitabine). Propensity score matching (PSM) was used to compare continuation of chemotherapy post-surgery vs. no postoperative treatment. RESULTS: Two hundred ten patients (67.3%) had GEJ and 102 (32.7%) lower esophageal adenocarcinoma. Microscopically clear surgical margins (R0), according to the Royal College of Pathologists, were achieved in 208 patients (66.7%). In total, 225 patients (72.1%) continued perioperative chemotherapy post-surgery. PSM was used to create two patient groups, well-balanced for basic epidemiological, clinical, and histopathological characteristics. The first included 148 patients who continued perioperative chemotherapy after surgery and the second 86, who did not receive postoperative treatment. The first group had non-significantly different median time-to-relapse (TTR 22.2 vs. 25.7 months, p = 0.627), overall survival (OS 46.1 vs. 36.7 months, p = 0.199), and post-relapse survival (15.3 vs. 8.7 months, p = 0.122). Subgroup analysis showed that only patients with microscopically residual disease after surgery (R1 resection) benefited from continuation of chemotherapy post-surgery for both TTR (hazard ratio [HR] 0.556, 95% CI 0.330-0.936, p = 0.027) and OS (HR 0.530, 95% CI 0.313-0.898, p = 0.018). CONCLUSIONS: Continuation of perioperative chemotherapy post-surgery was not associated with improved outcome in patients with E/GEJ adenocarcinoma. Patients with microscopically residual disease post-surgery might receive a potential benefit from adjuvant chemotherapy.


Assuntos
Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/cirurgia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Esofágicas/tratamento farmacológico , Neoplasias Esofágicas/cirurgia , Junção Esofagogástrica , Recidiva Local de Neoplasia , Adenocarcinoma/patologia , Idoso , Capecitabina/administração & dosagem , Quimioterapia Adjuvante , Cisplatino/administração & dosagem , Intervalo Livre de Doença , Epirubicina/administração & dosagem , Neoplasias Esofágicas/patologia , Esofagectomia , Junção Esofagogástrica/cirurgia , Feminino , Humanos , Masculino , Margens de Excisão , Pessoa de Meia-Idade , Terapia Neoadjuvante , Recidiva Local de Neoplasia/patologia , Neoplasia Residual , Período Perioperatório , Pontuação de Propensão , Estudos Retrospectivos , Taxa de Sobrevida
7.
Acta Oncol ; 57(6): 790-798, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29308947

RESUMO

BACKGROUND: Thromboembolic events (TEEs) represent a significant treatment and disease complication for cancer patients. In the present study we assessed the incidence of TEEs in patients receiving preoperative chemotherapy for esophagogastric adenocarcinoma. The risk factors for TEE development and their impact on prognosis were further analyzed. MATERIAL AND METHODS: Data from 590 patients with esophagogastric adenocarcinoma, who received preoperative epirubicin-cisplatin with capecitabine (ECX) or 5-fluorouracil (ECF) between 2009 and 2016 in three UK hospitals were retrospectively collected. RESULTS: Twenty-one percent had stomach primary and 98% received ECX chemotherapy. In total, 52 patients (9%) had a venous and 22 (4%) an arterial event. Of those patients with venous TEEs (vTTEs), 39 had pulmonary embolism and 13 deep vein thrombosis, whereas in patients with arterial TEEs (arTTEs), 7 developed a myocardial infarct, 8 developed limb ischemia, 4 developed cerebrovascular accidents and 3 developed superior mesenteric artery thrombosis. ArTEEs were associated with a much higher inoperability rate compared to cases without TEE or with vTEE (77% vs. 20% vs. 31%, respectively, p < .001). Independent risk factors of vTEEs were primary site being the stomach (Odds ratio [OR] 3.24, 95%CI 1.72-6.12, p < .001), being overweight (OR 3.11, 95%CI 1.33-7.26, p = .009) or obese (OR 4.52, 95%CI 1.85-11.09, p = .001) and the presence of central venous access device (OR 3.40, 95%CI 1.00-11.55, p = .050). In contrast, anticoagulant treatment was independently associated with a lower risk of vTEE (OR 0.22, 95%CI 0.06-0.83, p = .026). Khorana score of 4-5 was an independent risk factor of arTEE (OR 6.38, 95%CI 1.85-22.04, p = .003). Finally, arTEEs were an independent poor prognostic factor for OS, when adjusted for baseline patient, tumor and treatment characteristics (Hazard ratio 3.02, 95%CI 1.85-4.95, p < .001). CONCLUSION: Preoperative ECX/ECF chemotherapy for patients with resectable esophagogastric adenocarcinoma was associated with relatively high incidence of TEEs. However, only arTEEs affected patient survival outcomes.


Assuntos
Adenocarcinoma/tratamento farmacológico , Quimioterapia Adjuvante/efeitos adversos , Neoplasias Esofágicas/tratamento farmacológico , Terapia Neoadjuvante/efeitos adversos , Tromboembolia/epidemiologia , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Quimioterapia Adjuvante/métodos , Estudos de Coortes , Junção Esofagogástrica/patologia , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Terapia Neoadjuvante/métodos , Estudos Retrospectivos , Fatores de Risco , Neoplasias Gástricas/tratamento farmacológico , Tromboembolia/etiologia
8.
Cancers (Basel) ; 10(1)2018 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-29329208

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) continues to be a disease with poor outcomes and short-lived treatment responses. New information is emerging from genome sequencing identifying potential subgroups based on somatic and germline mutations. A variety of different mutations and mutational signatures have been identified; the driver mutation in around 93% of PDAC is KRAS, with other recorded alterations being SMAD4 and CDKN2A. Mutations in the deoxyribonucleic acid (DNA) damage repair pathway have also been investigated in PDAC and multiple clinical trials are ongoing with DNA-damaging agents. Rare mutations in BRAF and microsatellite instability (MSI) have been reported in about 1-3% of patients with PDAC, and agents used in other cancers to target these have also shown some promise. Immunotherapy is a developing field, but has failed to demonstrate benefits in PDAC to date. While many trials have failed to improve outcomes in this deadly disease, there is optimism that by developing a better understanding of the translational aspects of this cancer, future informed therapeutic strategies may prove more successful.

10.
Genome Res ; 27(6): 902-912, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28465312

RESUMO

The scientific community has avoided using tissue samples from patients that have been exposed to systemic chemotherapy to infer the genomic landscape of a given cancer. Esophageal adenocarcinoma is a heterogeneous, chemoresistant tumor for which the availability and size of pretreatment endoscopic samples are limiting. This study compares whole-genome sequencing data obtained from chemo-naive and chemo-treated samples. The quality of whole-genomic sequencing data is comparable across all samples regardless of chemotherapy status. Inclusion of samples collected post-chemotherapy increased the proportion of late-stage tumors. When comparing matched pre- and post-chemotherapy samples from 10 cases, the mutational signatures, copy number, and SNV mutational profiles reflect the expected heterogeneity in this disease. Analysis of SNVs in relation to allele-specific copy-number changes pinpoints the common ancestor to a point prior to chemotherapy. For cases in which pre- and post-chemotherapy samples do show substantial differences, the timing of the divergence is near-synchronous with endoreduplication. Comparison across a large prospective cohort (62 treatment-naive, 58 chemotherapy-treated samples) reveals no significant differences in the overall mutation rate, mutation signatures, specific recurrent point mutations, or copy-number events in respect to chemotherapy status. In conclusion, whole-genome sequencing of samples obtained following neoadjuvant chemotherapy is representative of the genomic landscape of esophageal adenocarcinoma. Excluding these samples reduces the material available for cataloging and introduces a bias toward the earlier stages of cancer.


Assuntos
Adenocarcinoma/genética , Antineoplásicos/uso terapêutico , Neoplasias Esofágicas/genética , Regulação Neoplásica da Expressão Gênica , Genoma Humano , Taxa de Mutação , Proteínas de Neoplasias/genética , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Idoso , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Transformação Celular Neoplásica/patologia , Biologia Computacional , Variações do Número de Cópias de DNA , Neoplasias Esofágicas/tratamento farmacológico , Neoplasias Esofágicas/metabolismo , Neoplasias Esofágicas/patologia , Esôfago/metabolismo , Esôfago/patologia , Feminino , Perfilação da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Pessoa de Meia-Idade , Terapia Neoadjuvante/métodos , Proteínas de Neoplasias/metabolismo , Mutação Puntual , Polimorfismo de Nucleotídeo Único , Estudos Prospectivos , Fatores de Tempo
11.
Acta Oncol ; 56(9): 1224-1232, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28524708

RESUMO

BACKGROUND: The new American Joint Committee on Cancer eighth edition (AJCC8) staging is the first to describe separate clinical and pathology staging systems, but still has low performance to predict prognosis in patients with oesophageal/gastroesophageal junction (O/GOJ) adenocarcinoma, who are candidates for surgery. Recent studies have demonstrated that O/GOJ cancer patients with 18F-fluorodeoxyglucose (FDG) avid regional lymph nodes (RLNs) may have poor prognosis. The aim of our study was to examine whether the baseline assessment of the FDG uptake of RLN improves the prognostic accuracy of the new AJCC8 staging. PATIENTS AND METHODS: This single-centre retrospective study included patients with operable FDG avid O/GOJ adenocarcinoma treated with perioperative chemotherapy. All patients were reclassified according to the new AJCC8 clinical staging. Prognostic factors for time-to-progression (TTP) and overall survival (OS) were explored. RESULTS: Of 430 patients included in the study, 180 (41.9%) had FDG avid RLN at baseline PET/CT scan before starting perioperative chemotherapy. The presence of FDG avid RLN was significantly and independently associated with shorter TTP and OS, especially in clinical stage III patients (p < .001 in both cases). Stage III patients with FDG avid RLN had similar TTP and OS to those with stage IVA. Classifying stage III patients with FDG avid RLN into stage IVA led to a significant improvement of the prognostic accuracy of the new AJCC8 clinical staging system (Harrell's concordance index improved from 0.555 to 0.588, p < .001). Of 430 patients starting perioperative chemotherapy, 332 underwent radical tumour resection. The presence of FDG avid RLN before starting perioperative chemotherapy could additionally predict a significantly shorter postoperative time-to-relapse and OS (p < .001 in both cases). CONCLUSIONS: We propose that the incorporation of RLN status (by FDG PET/CT scan) into the AJCC8 staging system of O/GOJ adenocarcinoma improves its prognostic accuracy and may also improve treatment stratification.


Assuntos
Adenocarcinoma/secundário , Neoplasias Esofágicas/patologia , Junção Esofagogástrica/patologia , Fluordesoxiglucose F18/metabolismo , Linfonodos/patologia , Recidiva Local de Neoplasia/patologia , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Adenocarcinoma/diagnóstico por imagem , Adenocarcinoma/metabolismo , Adenocarcinoma/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Esofágicas/diagnóstico por imagem , Neoplasias Esofágicas/metabolismo , Neoplasias Esofágicas/cirurgia , Junção Esofagogástrica/diagnóstico por imagem , Junção Esofagogástrica/metabolismo , Junção Esofagogástrica/cirurgia , Feminino , Humanos , Linfonodos/diagnóstico por imagem , Linfonodos/cirurgia , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Imagem Multimodal , Recidiva Local de Neoplasia/diagnóstico por imagem , Recidiva Local de Neoplasia/metabolismo , Recidiva Local de Neoplasia/cirurgia , Prognóstico , Compostos Radiofarmacêuticos/metabolismo , Estudos Retrospectivos
12.
Nat Genet ; 47(9): 1038-1046, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26192915

RESUMO

The molecular genetic relationship between esophageal adenocarcinoma (EAC) and its precursor lesion, Barrett's esophagus, is poorly understood. Using whole-genome sequencing on 23 paired Barrett's esophagus and EAC samples, together with one in-depth Barrett's esophagus case study sampled over time and space, we have provided the following new insights: (i) Barrett's esophagus is polyclonal and highly mutated even in the absence of dysplasia; (ii) when cancer develops, copy number increases and heterogeneity persists such that the spectrum of mutations often shows surprisingly little overlap between EAC and adjacent Barrett's esophagus; and (iii) despite differences in specific coding mutations, the mutational context suggests a common causative insult underlying these two conditions. From a clinical perspective, the histopathological assessment of dysplasia appears to be a poor reflection of the molecular disarray within the Barrett's epithelium, and a molecular Cytosponge technique overcomes sampling bias and has the capacity to reflect the entire clonal architecture.


Assuntos
Adenocarcinoma/genética , Esôfago de Barrett/genética , Neoplasias Esofágicas/genética , Idoso , Variações do Número de Cópias de DNA , Análise Mutacional de DNA , Progressão da Doença , Feminino , Genoma Humano , Estudo de Associação Genômica Ampla , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único
13.
BMC Genomics ; 16: 473, 2015 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-26159513

RESUMO

BACKGROUND: Mobile elements are active in the human genome, both in the germline and cancers, where they can mutate driver genes. RESULTS: While analysing whole genome paired-end sequencing of oesophageal adenocarcinomas to find genomic rearrangements, we identified three ways in which new mobile element insertions appear in the data, resembling translocation or insertion junctions: inserts where unique sequence has been transduced by an L1 (Long interspersed element 1) mobile element; novel inserts that are confidently, but often incorrectly, mapped by alignment software to L1s or polyA tracts in the reference sequence; and a combination of these two ways, where different sequences within one insert are mapped to different loci. We identified nine unique sequences that were transduced by neighbouring L1s, both L1s in the reference genome and L1s not present in the reference. Many of the resulting inserts were small fragments that include little or no recognisable mobile element sequence. We found 6 loci in the reference genome to which sequence reads from inserts were frequently mapped, probably erroneously, by alignment software: these were either L1 sequence or particularly long polyA runs. Inserts identified from such apparent rearrangement junctions averaged 16 inserts/tumour, range 0-153 insertions in 43 tumours. However, many inserts would not be detected by mapping the sequences to the reference genome, because they do not include sufficient mappable sequence. To estimate total somatic inserts we searched for polyA sequences that were not present in the matched normal or other normals from the same tumour batch, and were not associated with known polymorphisms. Samples of these candidate inserts were verified by sequencing across them or manual inspection of surrounding reads: at least 85 % were somatic and resembled L1-mediated events, most including L1Hs sequence. Approximately 100 such inserts were detected per tumour on average (range zero to approximately 700). CONCLUSIONS: Somatic mobile elements insertions are abundant in these tumours, with over 75 % of cases having a number of novel inserts detected. The inserts create a variety of problems for the interpretation of paired-end sequencing data.


Assuntos
Adenocarcinoma/genética , Elementos de DNA Transponíveis/genética , Neoplasias Esofágicas/genética , Mutagênese Insercional/genética , Idoso , Idoso de 80 Anos ou mais , Linhagem Celular Tumoral , Feminino , Rearranjo Gênico , Genoma Humano/genética , Humanos , Elementos Nucleotídeos Longos e Dispersos/genética , Masculino , Pessoa de Meia-Idade , Polimorfismo Genético/genética , Análise de Sequência de DNA/métodos
14.
Nat Genet ; 46(8): 837-843, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24952744

RESUMO

Cancer genome sequencing studies have identified numerous driver genes, but the relative timing of mutations in carcinogenesis remains unclear. The gradual progression from premalignant Barrett's esophagus to esophageal adenocarcinoma (EAC) provides an ideal model to study the ordering of somatic mutations. We identified recurrently mutated genes and assessed clonal structure using whole-genome sequencing and amplicon resequencing of 112 EACs. We next screened a cohort of 109 biopsies from 2 key transition points in the development of malignancy: benign metaplastic never-dysplastic Barrett's esophagus (NDBE; n=66) and high-grade dysplasia (HGD; n=43). Unexpectedly, the majority of recurrently mutated genes in EAC were also mutated in NDBE. Only TP53 and SMAD4 mutations occurred in a stage-specific manner, confined to HGD and EAC, respectively. Finally, we applied this knowledge to identify high-risk Barrett's esophagus in a new non-endoscopic test. In conclusion, mutations in EAC driver genes generally occur exceptionally early in disease development with profound implications for diagnostic and therapeutic strategies.


Assuntos
Carcinogênese/genética , Neoplasias Esofágicas/genética , Mutação , Lesões Pré-Cancerosas/genética , Adenocarcinoma/genética , Adenocarcinoma/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Esôfago de Barrett/genética , Esôfago de Barrett/patologia , Neoplasias Esofágicas/patologia , Feminino , Estudo de Associação Genômica Ampla/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Lesões Pré-Cancerosas/patologia , Análise de Sequência de DNA/métodos
15.
Nat Rev Gastroenterol Hepatol ; 11(1): 19-27, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23982683

RESUMO

Oesophageal adenocarcinoma (OAC) is the eighth most common cancer type worldwide with a dismal 5-year survival. Barrett oesophagus, the replacement of the normal squamous epithelia with glandular cells, is the first step in the pathway towards OAC. Although most patients with OAC present de novo, the presence of the easily detectable OAC precursor lesion, Barrett oesophagus, enables the possibility of early detection of high-risk patients who are more likely to progress. Currently, identification of high-risk patients depends on histopathological assessment of dysplasia with no regards to molecular pathogenesis. In the future, screening and risk stratification initiatives for Barrett oesophagus that incorporate molecular profiles might permit improved early diagnosis and intervention strategies with the possibility of preventing OAC. For the majority of patients presenting de novo at an advanced stage, combining so-called -omics datasets with current clinical staging algorithms might enable OACs to be better classified according to distinct molecular programmes, thereby leading to better targeted treatment strategies as well as cancer monitoring regimes. This Review discusses how the latest advances in -omics technologies have improved our understanding of the development and biology of OAC, and how this development might alter patient management in the future.


Assuntos
Adenocarcinoma/genética , Gerenciamento Clínico , Neoplasias Esofágicas/genética , Genômica/tendências , Adenocarcinoma/epidemiologia , Algoritmos , Esôfago de Barrett/diagnóstico , Esôfago de Barrett/genética , Detecção Precoce de Câncer , Neoplasias Esofágicas/epidemiologia , Humanos , Fatores de Risco
16.
Int J Cancer ; 131(5): 1104-13, 2012 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-22020830

RESUMO

We have previously identified a region containing 16 CpGs within the MGMT CpG islands which is critical for the transcriptional control of MGMT (Malley, Acta Neuropathol 2011). To investigate the patterns and incidence of MGMT methylation in astrocytic and oligodendroglial tumors, we quantitatively assessed methylation at these 16 CpGs using bisulfite modification followed by pyrosequencing of 362 gliomas not treated with temozolomide, and correlated the findings with previously identified patterns of genetic abnormalities, patients' age and survival. The MGMT gene was considered to be methylated when the mean methylation of the 16 CpGs was 10% or higher. This cut-off value distinguished diffuse astrocytomas with high and low MGMT expression. Within each tumor type, the patterns of methylation were highly variable and also highly heterogeneous across the 16 CpGs. A high incidence of MGMT methylation was observed in all subtypes of gliomas included in this study. Among a subset of 97 tumors where conventional methylation-specific PCR (MSP) was also applied, methylation was detected by both methods in 54 tumors, while the pyrosequencing results identified a further 17 tumors. No additional cases were found using MSP alone, indicating that pyrosequencing is a robust method for methylation analysis. All tumors with IDH1/IDH2 mutations except two had MGMT methylation, while there were many tumors with MGMT methylation, particularly primary glioblastomas, which had no mutations of IDH1/2. We suggest that MGMT methylation may be one of the earliest events in the development of astrocytic and oligodendroglial tumors.


Assuntos
Astrocitoma/genética , Ilhas de CpG/genética , Metilação de DNA , Metilases de Modificação do DNA/genética , Enzimas Reparadoras do DNA/genética , Isocitrato Desidrogenase/genética , Mutação/genética , Oligodendroglioma/genética , Proteínas Supressoras de Tumor/genética , Adolescente , Adulto , Astrocitoma/mortalidade , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/mortalidade , Criança , DNA de Neoplasias/genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Oligodendroglioma/mortalidade , Prognóstico , Regiões Promotoras Genéticas/genética , Reação em Cadeia da Polimerase em Tempo Real , Taxa de Sobrevida , Adulto Jovem
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