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1.
Cancers (Basel) ; 16(8)2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38672547

RESUMO

BACKGROUND: Immune checkpoint inhibitors (ICIs) improve overall survival (OS) in advanced/metastatic urothelial cancer (a/mUC) patients. Preliminary evidence suggests a prognostic role of inflammatory biomarkers in this setting. We aimed to develop a disease-specific prognostic inflammatory index for a/mUC patients on ICIs. METHODS: Fifteen variables were retrospectively correlated with OS and progression-free survival (PFS) in a development (D, n = 264) and a validation (V, n = 132) cohort of platinum-pretreated a/mUC pts receiving ICIs at L2 or further line. A nomogram and inflammatory prognostic index (U-IPI) were developed. The index was also tested in a control cohort of patients treated with chemotherapy only (C, n = 114). RESULTS: The strongest predictors of OS were baseline platelet/lymphocyte (PLR) and neutrophil/lymphocyte (NLR) ratios, and lactate dehydrogenase (LDH), NLR, and albumin changes at 4 weeks. These were used to build the U-IPI, which can distinctly classify patients into good or poor response groups. The nomogram scoring is significant for PFS and OS (p < 0.001 in the D, V, and combined cohorts) for the immunotherapy (IO) cohort, but not for the control cohort. CONCLUSIONS: The lack of a baseline systemic inflammatory profile and the absence of early serum inflammatory biomarker changes are associated with significantly better outcomes on ICIs in a/mUC pts. The U-IPI is an easily applicable dynamic prognostic tool for PFS and OS, allowing for the early identification of a sub-group with dismal outcomes that would not benefit from ICIs, while distinguishing another that draws an important benefit.

2.
Nat Genet ; 56(3): 458-472, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38351382

RESUMO

Molecular stratification using gene-level transcriptional data has identified subtypes with distinctive genotypic and phenotypic traits, as exemplified by the consensus molecular subtypes (CMS) in colorectal cancer (CRC). Here, rather than gene-level data, we make use of gene ontology and biological activation state information for initial molecular class discovery. In doing so, we defined three pathway-derived subtypes (PDS) in CRC: PDS1 tumors, which are canonical/LGR5+ stem-rich, highly proliferative and display good prognosis; PDS2 tumors, which are regenerative/ANXA1+ stem-rich, with elevated stromal and immune tumor microenvironmental lineages; and PDS3 tumors, which represent a previously overlooked slow-cycling subset of tumors within CMS2 with reduced stem populations and increased differentiated lineages, particularly enterocytes and enteroendocrine cells, yet display the worst prognosis in locally advanced disease. These PDS3 phenotypic traits are evident across numerous bulk and single-cell datasets, and demark a series of subtle biological states that are currently under-represented in pre-clinical models and are not identified using existing subtyping classifiers.


Assuntos
Neoplasias Colorretais , Humanos , Neoplasias Colorretais/patologia , Prognóstico , Diferenciação Celular/genética , Fenótipo , Biomarcadores Tumorais/genética , Perfilação da Expressão Gênica
4.
Swiss Med Wkly ; 153: 40108, 2023 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-37598311

RESUMO

The management of prostate cancer is undergoing rapid changes in all disease settings. Novel imaging tools for diagnosis have been introduced, and the treatment of high-risk localized, locally advanced and metastatic disease has changed considerably in recent years. From clinical and health-economic perspectives, a rational and optimal use of the available options is of the utmost importance. While international guidelines list relevant pivotal trials and give recommendations for a variety of clinical scenarios, there is much room for interpretation, and several important questions remain highly debated. The goal of developing a national consensus on the use of these novel diagnostic and therapeutic strategies in order to improve disease management and eventually patient outcomes has prompted a Swiss consensus meeting. Experts from several specialties, including urology, medical oncology, radiation oncology, pathology and nuclear medicine, discussed and voted on questions of the current most important areas of uncertainty, including the staging and treatment of high-risk localized disease, treatment of metastatic hormone-sensitive prostate cancer (mHSPC) and use of new options to treat metastatic castration-resistant prostate cancer (mCRPC).


Assuntos
Neoplasias da Próstata , Masculino , Humanos , Consenso , Suíça , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/terapia , Estudos Interdisciplinares , Oncologia
5.
Int J Cancer ; 153(9): 1568-1578, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37306359

RESUMO

The spatial distribution of tumor-infiltrating lymphocytes (TIL) predicts breast cancer outcome and response to systemic therapy, highlighting the importance of an intact tissue structure for characterizing tumors. Here, we present ST-FFPE, a spatial transcriptomics method for the analysis of formalin-fixed paraffin-embedded samples, which opens the possibility of interrogating archival tissue. The method involves extraction, exome capture and sequencing of RNA from different tumor compartments microdissected by laser-capture, and can be used to study the cellular composition of tumor microenvironment. Focusing on triple-negative breast cancer (TNBC), we characterized T cells, B cells, dendritic cells, fibroblasts and endothelial cells in both stromal and intra-epithelial compartments. We found a highly variable spatial distribution of immune cell subsets among tumors. This analysis revealed that the immune repertoires of intra-epithelial T and B cells were consistently less diverse and more clonal than those of stromal T and B cells. T-cell receptor (TCR) sequencing confirmed a reduced diversity and higher clonality of intra-epithelial T cells relative to the corresponding stromal T cells. Analysis of the top 10 dominant clonotypes in the two compartments showed a majority of shared but also some unique clonotypes both in stromal and intra-epithelial T cells. Hyperexpanded clonotypes were more abundant among intra-epithelial than stromal T cells. These findings validate the ST-FFPE method and suggest an accumulation of antigen-specific T cells within tumor core. Because ST-FFPE is applicable for analysis of previously collected tissue samples, it could be useful for rapid assessment of intratumoral cellular heterogeneity in multiple disease and treatment settings.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/genética , Células Endoteliais , Transcriptoma , Receptores de Antígenos de Linfócitos T , Perfilação da Expressão Gênica , Linfócitos do Interstício Tumoral , Microambiente Tumoral/genética
6.
Front Digit Health ; 5: 1195017, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37388252

RESUMO

Objectives: The objective of this study is the exploration of Artificial Intelligence and Natural Language Processing techniques to support the automatic assignment of the four Response Evaluation Criteria in Solid Tumors (RECIST) scales based on radiology reports. We also aim at evaluating how languages and institutional specificities of Swiss teaching hospitals are likely to affect the quality of the classification in French and German languages. Methods: In our approach, 7 machine learning methods were evaluated to establish a strong baseline. Then, robust models were built, fine-tuned according to the language (French and German), and compared with the expert annotation. Results: The best strategies yield average F1-scores of 90% and 86% respectively for the 2-classes (Progressive/Non-progressive) and the 4-classes (Progressive Disease, Stable Disease, Partial Response, Complete Response) RECIST classification tasks. Conclusions: These results are competitive with the manual labeling as measured by Matthew's correlation coefficient and Cohen's Kappa (79% and 76%). On this basis, we confirm the capacity of specific models to generalize on new unseen data and we assess the impact of using Pre-trained Language Models (PLMs) on the accuracy of the classifiers.

7.
Praxis (Bern 1994) ; 112(3): 149-155, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36855887

RESUMO

Immunotherapy is becoming increasingly important in the management of urological, gynecological, and gastrointestinal cancers. Immune checkpoint inhibitor-based combinations have become a standard of care for patients with metastatic renal and liver cancers, as well as for many patients with bladder, cervical, gastric, and esophageal cancers, based on various biomarkers. Some tumor types are less responsive to immunotherapy, such as prostate and colon cancer. In these tumors, however, a subgroup of patients with a microsatellite-instability-high/DNA-mismatch repair deficient molecular phenotype significantly benefits from immunotherapy. Molecular characterization is therefore essential to identify patients who may benefit from these treatments. One of the major challenges is the search for new predictive biomarkers and novel combinations or strategies to further improve patient outcome.


Assuntos
Neoplasias Gastrointestinais , Ginecologia , Neoplasias Hepáticas , Masculino , Humanos , Neoplasias Gastrointestinais/diagnóstico , Neoplasias Gastrointestinais/terapia , Imunoterapia , Rim
8.
Int J Mol Sci ; 24(5)2023 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-36901951

RESUMO

The development of targeted therapies for non-BRAF p.Val600-mutant melanomas remains a challenge. Triple wildtype (TWT) melanomas that lack mutations in BRAF, NRAS, or NF1 form 10% of human melanomas and are heterogeneous in their genomic drivers. MAP2K1 mutations are enriched in BRAF-mutant melanoma and function as an innate or adaptive resistance mechanism to BRAF inhibition. Here we report the case of a patient with TWT melanoma with a bona fide MAP2K1 mutation without any BRAF mutations. We performed a structural analysis to validate that the MEK inhibitor trametinib could block this mutation. Although the patient initially responded to trametinib, he eventually progressed. The presence of a CDKN2A deletion prompted us to combine a CDK4/6 inhibitor, palbociclib, with trametinib but without clinical benefit. Genomic analysis at progression showed multiple novel copy number alterations. Our case illustrates the challenges of combining MEK1 and CDK4/6 inhibitors in case of resistance to MEK inhibitor monotherapy.


Assuntos
Melanoma , Neoplasias Cutâneas , Masculino , Humanos , Neoplasias Cutâneas/genética , Melanoma/genética , Piridonas/uso terapêutico , Pirimidinonas/uso terapêutico , Inibidores de Proteínas Quinases/farmacologia , Quinases de Proteína Quinase Ativadas por Mitógeno/genética , Proteínas Proto-Oncogênicas B-raf/genética , Mutação , MAP Quinase Quinase 1/genética
10.
J Gastroenterol ; 58(2): 125-134, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36357817

RESUMO

BACKGROUND: Rectal cancers represent 35% of colorectal cancers; 90% are adenocarcinomas, while squamous cell carcinoma accounts for 0.3% of them. Given its rarity, little is known concerning its pathogenesis, molecular profile and therapeutic management. The current treatment trend is to treat rectal squamous cell carcinoma by analogy to anal squamous cell carcinoma with definitive chemo-radiotherapy, setting aside surgery in case of local recurrence. METHODS: We performed an in-depth genomic analysis (next-generation sequencing, copy number variation, and human papilloma virus characterization) on 10 rectal squamous cell carcinoma samples and compared them in silico to those of anal squamous cell carcinoma and rectal adenocarcinoma. RESULTS: Rectal squamous cell carcinoma shows 100% HPV positivity. It has a mutational (PIK3CA, PTEN, TP53, ATM, BCL6, SOX2) and copy number variation profile (3p, 10p, 10q, 16q deletion and 1q, 3q, 5p, 8q, 20p gain) similar to anal squamous cell carcinoma. PI3K/Akt/mTOR is the most commonly affected signaling pathway similarly to anal squamous cell carcinoma. Most commonly gained or lost genes seen in rectal adenocarcinoma (FLT3, CDX2, GNAS, BCL2, SMAD4, MALT1) are not found in rectal squamous cell carcinoma. CONCLUSION: This study presents the first comprehensive genomic characterization of rectal squamous cell carcinoma. We confirm the existence of this rare histology and its molecular similarity with anal squamous cell carcinoma. This molecular proximity confirms the adequacy of therapeutic management based on histology and not localization, suggesting that rectal squamous cell carcinoma should be treated like anal squamous cell carcinoma and not as a rectal adenocarcinoma.


Assuntos
Adenocarcinoma , Carcinoma de Células Escamosas , Neoplasias Retais , Humanos , Variações do Número de Cópias de DNA , Fosfatidilinositol 3-Quinases/genética , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/terapia , Carcinoma de Células Escamosas/patologia , Neoplasias Retais/genética , Neoplasias Retais/terapia , Neoplasias Retais/patologia , Adenocarcinoma/genética , Adenocarcinoma/terapia , Adenocarcinoma/patologia , Genômica
11.
Swiss Med Wkly ; 153: 3504, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-38579317

RESUMO

BACKGROUND: The development of immunotherapy and tyrosine kinase inhibitors dramatically improved the prognosis of metastatic melanoma. Consequently, chemotherapy is now rarely used. Here, we describe the characteristics of long-surviving patients with metastatic melanoma treated with immunochemotherapy. MATERIAL AND METHODS: We retrieved retrospective clinical and pathological data for patients diagnosed with metastatic melanoma between January 1993 and December 2015 who received the CVD-INF (cisplatin, vinblastine, dacarbazine, and interferon α-2b) regimen at the Hôpitaux Universitaires de Genève. We estimated their progression-free survival and overall survival. This ad hoc study's primary aim was to describe the clinical and biological characteristics of long-term survivors, defined as patients surviving more than two years after immunochemotherapy initiation. The spatial distribution pattern of CD8+ T cells (inflamed, excluded, or desert) was immunohistochemically determined. RESULTS: Ninety patients received CVD-INF. Their median age at metastatic melanoma diagnosis was 55 years (20-75). Their median progression-free survival was 2.8 months, and median overall survival was 7.2 months. Eleven (12%) patients were long-term survivors. In multivariate analysis, central nervous system metastases (hazard ratio [HR]: 2.66; 95% confidence interval [CI]: 1.43-4.95; p = 0.001), multiple metastases (HR: 1.82; 95% CI: 1.01-3.29; p = 0.047), and elevated lactate dehydrogenase (LDH) (HR: 1.92; 95% CI: 1.12-3.30; p = 0.016) were independently associated with shorter survival. Most long-survivors (6/8; 75%) had a tumour-inflamed pattern compared to 25% of non-long survivors (5/20; Fisher's test p = 0.030). CONCLUSIONS: A subset of patients with metastatic melanoma and a tumour-inflamed phenotype treated with CVD-INF survived over two years. Factors associated with prolonged survival are consistent with those previously reported in metastatic melanoma.


Assuntos
Doenças Cardiovasculares , Melanoma , Neoplasias Cutâneas , Humanos , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso , Melanoma/tratamento farmacológico , Estudos Retrospectivos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Resultado do Tratamento , Interleucina-2 , Neoplasias Cutâneas/tratamento farmacológico
13.
Cell Stem Cell ; 29(8): 1213-1228.e8, 2022 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-35931031

RESUMO

Intestinal homeostasis is underpinned by LGR5+ve crypt-base columnar stem cells (CBCs), but following injury, dedifferentiation results in the emergence of LGR5-ve regenerative stem cell populations (RSCs), characterized by fetal transcriptional profiles. Neoplasia hijacks regenerative signaling, so we assessed the distribution of CBCs and RSCs in mouse and human intestinal tumors. Using combined molecular-morphological analysis, we demonstrate variable expression of stem cell markers across a range of lesions. The degree of CBC-RSC admixture was associated with both epithelial mutation and microenvironmental signaling disruption and could be mapped across disease molecular subtypes. The CBC-RSC equilibrium was adaptive, with a dynamic response to acute selective pressure, and adaptability was associated with chemoresistance. We propose a fitness landscape model where individual tumors have equilibrated stem cell population distributions along a CBC-RSC phenotypic axis. Cellular plasticity is represented by position shift along this axis and is influenced by cell-intrinsic, extrinsic, and therapeutic selective pressures.


Assuntos
Neoplasias Colorretais , Mucosa Intestinal , Animais , Neoplasias Colorretais/patologia , Homeostase/fisiologia , Humanos , Mucosa Intestinal/metabolismo , Intestinos , Camundongos , Células-Tronco Neoplásicas/patologia , Receptores Acoplados a Proteínas G/metabolismo
14.
Sci Rep ; 12(1): 12528, 2022 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-35869122

RESUMO

The BRAF kinase is attracting a lot of attention in oncology as alterations of its amino acid sequence can constitutively activate the MAP kinase signaling pathway, potentially contributing to the malignant transformation of the cell but at the same time rendering it sensitive to targeted therapy. Several pathologic BRAF variants were grouped in three different classes (I, II and III) based on their effects on the protein activity and pathway. Discerning the class of a BRAF mutation permits to adapt the treatment proposed to the patient. However, this information is lacking new and experimentally uncharacterized BRAF mutations detected in a patient biopsy. To overcome this issue, we developed a new in silico tool based on machine learning approaches to predict the potential class of a BRAF missense variant. As class I only involves missense mutations of Val600, we focused on the mutations of classes II and III, which are more diverse and challenging to predict. Using a logistic regression model and features including structural information, we were able to predict the classes of known mutations with an accuracy of 90%. This new and fast predictive tool will help oncologists to tackle potential pathogenic BRAF mutations and to propose the most appropriate treatment for their patients.


Assuntos
Sistema de Sinalização das MAP Quinases , Proteínas Proto-Oncogênicas B-raf , Humanos , Aprendizado de Máquina , Mutação , Mutação de Sentido Incorreto , Proteínas Proto-Oncogênicas B-raf/química , Proteínas Proto-Oncogênicas B-raf/genética
15.
Nat Genet ; 54(7): 963-975, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35773407

RESUMO

The consensus molecular subtype (CMS) classification of colorectal cancer is based on bulk transcriptomics. The underlying epithelial cell diversity remains unclear. We analyzed 373,058 single-cell transcriptomes from 63 patients, focusing on 49,155 epithelial cells. We identified a pervasive genetic and transcriptomic dichotomy of malignant cells, based on distinct gene expression, DNA copy number and gene regulatory network. We recapitulated these subtypes in bulk transcriptomes from 3,614 patients. The two intrinsic subtypes, iCMS2 and iCMS3, refine CMS. iCMS3 comprises microsatellite unstable (MSI-H) cancers and one-third of microsatellite-stable (MSS) tumors. iCMS3 MSS cancers are transcriptomically more similar to MSI-H cancers than to other MSS cancers. CMS4 cancers had either iCMS2 or iCMS3 epithelium; the latter had the worst prognosis. We defined the intrinsic epithelial axis of colorectal cancer and propose a refined 'IMF' classification with five subtypes, combining intrinsic epithelial subtype (I), microsatellite instability status (M) and fibrosis (F).


Assuntos
Neoplasias Colorretais , Neoplasias Epiteliais e Glandulares , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Células Epiteliais/patologia , Humanos , Instabilidade de Microssatélites , Repetições de Microssatélites/genética , Neoplasias Epiteliais e Glandulares/genética , Transcriptoma/genética
16.
Front Oncol ; 12: 817548, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35515125

RESUMO

Lung cancer is the leading cause of cancer mortality worldwide. Immunotherapy has demonstrated clinically significant benefit for non-small-cell lung cancer, but innate (primary) or acquired resistance remains a challenge. Criteria for a uniform clinical definition of acquired resistance have been recently proposed in order to harmonize the design of future clinical trials. Several mechanisms of resistance are now well-described, including the lack of tumor antigens, defective antigen presentation, modulation of critical cellular pathways, epigenetic changes, and changes in the tumor microenvironment. Host-related factors, such as the microbiome and the state of immunity, have also been examined. New compounds and treatment strategies are being developed to target these mechanisms with the goal of maximizing the benefit derived from immunotherapy. Here we review the definitions of resistance to immunotherapy, examine its underlying mechanisms and potential corresponding treatment strategies. We focus on recently published clinical trials and trials that are expected to deliver results soon. Finally, we gather insights from recent preclinical discoveries that may translate to clinical application in the future.

17.
Gut ; 71(12): 2502-2517, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35477539

RESUMO

OBJECTIVE: Stroma-rich tumours represent a poor prognostic subtype in stage II/III colon cancer (CC), with high relapse rates and limited response to standard adjuvant chemotherapy. DESIGN: To address the lack of efficacious therapeutic options for patients with stroma-rich CC, we stratified our human tumour cohorts according to stromal content, enabling identification of the biology underpinning relapse and potential therapeutic vulnerabilities specifically within stroma-rich tumours that could be exploited clinically. Following human tumour-based discovery and independent clinical validation, we use a series of in vitro and stroma-rich in vivo models to test and validate the therapeutic potential of elevating the biology associated with reduced relapse in human tumours. RESULTS: By performing our analyses specifically within the stroma-rich/high-fibroblast (HiFi) subtype of CC, we identify and validate the clinical value of a HiFi-specific prognostic signature (HPS), which stratifies tumours based on STAT1-related signalling (High-HPS v Low-HPS=HR 0.093, CI 0.019 to 0.466). Using in silico, in vitro and in vivo models, we demonstrate that the HPS is associated with antigen processing and presentation within discrete immune lineages in stroma-rich CC, downstream of double-stranded RNA and viral response signalling. Treatment with the TLR3 agonist poly(I:C) elevated the HPS signalling and antigen processing phenotype across in vitro and in vivo models. In an in vivo model of stroma-rich CC, poly(I:C) treatment significantly increased systemic cytotoxic T cell activity (p<0.05) and reduced liver metastases (p<0.0002). CONCLUSION: This study reveals new biological insight that offers a novel therapeutic option to reduce relapse rates in patients with the worst prognosis CC.


Assuntos
Biomarcadores Tumorais , Neoplasias do Colo , Humanos , Biomarcadores Tumorais/genética , Células Estromais/patologia , Recidiva Local de Neoplasia/prevenção & controle , Recidiva Local de Neoplasia/patologia , Neoplasias do Colo/patologia , Prognóstico
18.
Leukemia ; 36(5): 1237-1252, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35354920

RESUMO

Despite recent advances in acute myeloid leukemia (AML) molecular characterization and targeted therapies, a majority of AML cases still lack therapeutically actionable targets. In 127 AML cases with unmet therapeutic needs, as defined by the exclusion of ELN favorable cases and of FLT3-ITD mutations, we identified 51 (40%) cases with alterations in RAS pathway genes (RAS+, mostly NF1, NRAS, KRAS, and PTPN11 genes). In 79 homogeneously treated AML patients from this cohort, RAS+ status were associated with higher white blood cell count, higher LDH, and reduced survival. In AML models of oncogenic addiction to RAS-MEK signaling, the MEK inhibitor trametinib demonstrated antileukemic activity in vitro and in vivo. However, the efficacy of trametinib was heterogeneous in ex vivo cultures of primary RAS+ AML patient specimens. From repurposing drug screens in RAS-activated AML cells, we identified pyrvinium pamoate, an anti-helminthic agent efficiently inhibiting the growth of RAS+ primary AML cells ex vivo, preferentially in trametinib-resistant PTPN11- or KRAS-mutated samples. Metabolic and genetic complementarity between trametinib and pyrvinium pamoate translated into anti-AML synergy in vitro. Moreover, this combination inhibited the propagation of RA+ AML cells in vivo in mice, indicating a potential for future clinical development of this strategy in AML.


Assuntos
Leucemia Mieloide Aguda , Mutações Sintéticas Letais , Animais , Humanos , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Camundongos , Quinases de Proteína Quinase Ativadas por Mitógeno/genética , Mutação , Estresse Oxidativo , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Tirosina Quinase 3 Semelhante a fms/metabolismo
19.
J Mol Diagn ; 23(12): 1722-1731, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34454110

RESUMO

Copy number alterations are genetic events that promote tumor initiation and progression and are used in clinical care as diagnostic, prognostic, and predictive biomarkers. Based on the length of the alteration, they are roughly classified as focal and arm-level alterations. Although genome-wide techniques to detect arm-level alterations are gaining momentum in hospital laboratories, the high precision and novelty of these techniques pose new challenges: there is no consensus on the definition of an arm-level alteration and there is a lack of tools to compute them for individual patients. Based on 376 clinical samples analyzed with the OncoScan formalin-fixed, paraffin-embedded assay, a bimodal distribution of the percentage of bases with copy number alterations within a chromosomal arm was observed, with the second peak starting at 90% of arm length. Two approaches were tested for the definition of arm-level alterations: sum of altered segments (SoS) >90%, or the longest segment (LS) >90%. These approaches were validated against expert annotation of 25 clinical cases. The SoS method outperformed the LS method as indicated by a higher concordance (SoS, 95.2%; LS, 79.9%). Some of the discordances ultimately were attributed to human error, highlighting the advantages of automation. The increase in reliability led to the development of publicly available software and its inclusion into routine clinical practice at Geneva University Hospitals.


Assuntos
Cromossomos Humanos , Variações do Número de Cópias de DNA , Neoplasias/genética , Idoso , Automação Laboratorial , Aberrações Cromossômicas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/patologia , Inclusão em Parafina , Reprodutibilidade dos Testes , Fixação de Tecidos
20.
Nat Commun ; 12(1): 3464, 2021 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-34103493

RESUMO

Right-sided (proximal) colorectal cancer (CRC) has a poor prognosis and a distinct mutational profile, characterized by oncogenic BRAF mutations and aberrations in mismatch repair and TGFß signalling. Here, we describe a mouse model of right-sided colon cancer driven by oncogenic BRAF and loss of epithelial TGFß-receptor signalling. The proximal colonic tumours that develop in this model exhibit a foetal-like progenitor phenotype (Ly6a/Sca1+) and, importantly, lack expression of Lgr5 and its associated intestinal stem cell signature. These features are recapitulated in human BRAF-mutant, right-sided CRCs and represent fundamental differences between left- and right-sided disease. Microbial-driven inflammation supports the initiation and progression of these tumours with foetal-like characteristics, consistent with their predilection for the microbe-rich right colon and their antibiotic sensitivity. While MAPK-pathway activating mutations drive this foetal-like signature via ERK-dependent activation of the transcriptional coactivator YAP, the same foetal-like transcriptional programs are also initiated by inflammation in a MAPK-independent manner. Importantly, in both contexts, epithelial TGFß-receptor signalling is instrumental in suppressing the tumorigenic potential of these foetal-like progenitor cells.


Assuntos
Carcinogênese/metabolismo , Neoplasias do Colo/metabolismo , Proteínas Proto-Oncogênicas B-raf/metabolismo , Receptores de Fatores de Crescimento Transformadores beta/metabolismo , Transdução de Sinais , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Carcinogênese/patologia , Diferenciação Celular , Sobrevivência Celular , Colo/patologia , Neoplasias do Colo/genética , Células Epiteliais/metabolismo , Feto/patologia , Inflamação/patologia , Estimativa de Kaplan-Meier , Sistema de Sinalização das MAP Quinases , Camundongos Endogâmicos C57BL , Mutação , Prognóstico , Proteínas Proto-Oncogênicas B-raf/genética , Receptor do Fator de Crescimento Transformador beta Tipo I/metabolismo , Esferoides Celulares/metabolismo , Esferoides Celulares/patologia , Fatores de Transcrição/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Proteínas Wnt/metabolismo , Via de Sinalização Wnt , Proteínas de Sinalização YAP
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