RESUMO
BRAF(V600E) mutant colon cancers (CCs) have a characteristic gene expression signature that is also found in some tumors lacking this mutation. Collectively, they are referred to as "BRAF-like" tumors and represent some 20% of CCs. We used a shRNA-based genetic screen focused on genes upregulated in BRAF(V600E) CCs to identify vulnerabilities of this tumor subtype that might be exploited therapeutically. Here, we identify RANBP2 (also known as NUP358) as essential for survival of BRAF-like, but not for non-BRAF-like, CC cells. Suppression of RANBP2 results in mitotic defects only in BRAF-like CC cells, leading to cell death. Mechanistically, RANBP2 silencing reduces microtubule outgrowth from the kinetochores, thereby inducing spindle perturbations, providing an explanation for the observed mitotic defects. We find that BRAF-like CCs display far greater sensitivity to the microtubule poison vinorelbine both in vitro and in vivo, suggesting that vinorelbine is a potential tailored treatment for BRAF-like CCs.
Assuntos
Antineoplásicos Fitogênicos/farmacologia , Neoplasias do Colo/genética , Neoplasias do Colo/patologia , Vimblastina/análogos & derivados , Animais , Antineoplásicos Fitogênicos/administração & dosagem , Células Cultivadas , Neoplasias do Colo/classificação , Neoplasias do Colo/tratamento farmacológico , Xenoenxertos , Humanos , Camundongos , Camundongos Nus , Microtúbulos/efeitos dos fármacos , Microtúbulos/metabolismo , Chaperonas Moleculares/genética , Transplante de Neoplasias , Complexo de Proteínas Formadoras de Poros Nucleares/genética , Proteínas Proto-Oncogênicas B-raf/genética , Vimblastina/administração & dosagem , Vimblastina/farmacologia , VinorelbinaRESUMO
Tumor mutational signatures have gained prominence in cancer research, yet the lack of standardized methods hinders reproducibility and robustness. Leveraging colorectal cancer (CRC) as a model, we explored the influence of computational parameters on mutational signature analyses across 230 CRC cell lines and 152 CRC patients. Results were validated in three independent datasets: 483 endometrial cancer patients stratified by mismatch repair (MMR) status, 35 lung cancer patients by smoking status and 12 patient-derived organoids (PDOs) annotated for colibactin exposure. Assessing various bioinformatic tools, reference datasets and input data sizes including whole genome sequencing, whole exome sequencing and a pan-cancer gene panel, we demonstrated significant variability in the results. We report that the use of distinct algorithms and references led to statistically different results, highlighting how arbitrary choices may induce variability in the mutational signature contributions. Furthermore, we found a differential contribution of mutational signatures between coding and intergenic regions and defined the minimum number of somatic variants required for reliable mutational signature assignment. To facilitate the identification of the most suitable workflows, we developed Comparative Mutational Signature analysis on Coding and Extragenic Regions (CoMSCER), a bioinformatic tool which allows researchers to easily perform comparative mutational signature analysis by coupling the results from several tools and public reference datasets and to assess mutational signature contributions in coding and non-coding genomic regions. In conclusion, our study provides a comparative framework to elucidate the impact of distinct computational workflows on mutational signatures.
Assuntos
Neoplasias Colorretais , Biologia Computacional , Mutação , Humanos , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Biologia Computacional/métodos , Fluxo de Trabalho , Linhagem Celular Tumoral , Sequenciamento do Exoma/métodos , Feminino , AlgoritmosRESUMO
Molecular alterations in genes involved in DNA mismatch repair (MMR) promote cancer initiation and foster tumour progression. Cancers deficient in MMR frequently show favourable prognosis and indolent progression. The functional basis of the clinical outcome of patients with tumours that are deficient in MMR is not clear. Here we genetically inactivate MutL homologue 1 (MLH1) in colorectal, breast and pancreatic mouse cancer cells. The growth of MMR-deficient cells was comparable to their proficient counterparts in vitro and on transplantation in immunocompromised mice. By contrast, MMR-deficient cancer cells grew poorly when transplanted in syngeneic mice. The inactivation of MMR increased the mutational burden and led to dynamic mutational profiles, which resulted in the persistent renewal of neoantigens in vitro and in vivo, whereas MMR-proficient cells exhibited stable mutational load and neoantigen profiles over time. Immune surveillance improved when cancer cells, in which MLH1 had been inactivated, accumulated neoantigens for several generations. When restricted to a clonal population, the dynamic generation of neoantigens driven by MMR further increased immune surveillance. Inactivation of MMR, driven by acquired resistance to the clinical agent temozolomide, increased mutational load, promoted continuous renewal of neoantigens in human colorectal cancers and triggered immune surveillance in mouse models. These results suggest that targeting DNA repair processes can increase the burden of neoantigens in tumour cells; this has the potential to be exploited in therapeutic approaches.
Assuntos
Antígenos de Neoplasias/genética , Antígenos de Neoplasias/imunologia , Reparo de Erro de Pareamento de DNA/genética , Imunoterapia/métodos , Neoplasias/imunologia , Neoplasias/patologia , Animais , Anticorpos Antineoplásicos/imunologia , Anticorpos Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Proliferação de Células/genética , Feminino , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD , Camundongos SCID , Proteína 1 Homóloga a MutL/deficiência , Proteína 1 Homóloga a MutL/genética , Neoplasias/genética , Neoplasias/terapia , Receptores de Antígenos de Linfócitos T/imunologia , Evasão Tumoral/genética , Evasão Tumoral/imunologiaRESUMO
Drug resistance represents a major limitation to the long-term efficacy of anti-cancer treatments. The commonly accepted view is that the selection of inheritable genetic mechanisms governs the development of secondary resistance. However, compelling evidence suggests an important role for adaptive cell plasticity and non-genetic mechanisms in the development of therapy resistance. The two phenomena are not mutually exclusive and the interplay between genetic and non-genetic mechanisms may affect tumor evolution during treatment. A broader characterization of the genetic and non-genetic mechanisms of drug resistance may pave the way for more precise and effective therapeutic strategies to overcome resistance.
Assuntos
Neoplasias , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/genética , Resistência a Medicamentos , Epigênese Genética , Resistencia a Medicamentos Antineoplásicos/genéticaRESUMO
BACKGROUND: Despite recent therapeutic advances, combating cancer resistance remains a formidable challenge. The 78-kilodalton glucose-regulated protein (GRP78), a key stress-inducible endoplasmic reticulum (ER) chaperone, plays a crucial role in both cancer cell survival and stress adaptation. GRP78 is also upregulated during SARS-CoV-2 infection and acts as a critical host factor. Recently, we discovered cardiac glycosides (CGs) as novel suppressors of GRP78 stress induction through a high-throughput screen of clinically relevant compound libraries. This study aims to test the possibility that agents capable of blocking stress induction of GRP78 could dually suppress cancer and COVID-19. RESULTS: Here we report that oleandrin (OLN), is the most potent among the CGs in inhibiting acute stress induction of total GRP78, which also results in reduced cell surface and nuclear forms of GRP78 in stressed cells. The inhibition of stress induction of GRP78 is at the post-transcriptional level, independent of protein degradation and autophagy and may involve translational control as OLN blocks stress-induced loading of ribosomes onto GRP78 mRNAs. Moreover, the human Na+/K+-ATPase α3 isoform is critical for OLN suppression of GRP78 stress induction. OLN, in nanomolar range, enhances apoptosis, sensitizes colorectal cancer cells to chemotherapeutic agents, and reduces the viability of patient-derived colon cancer organoids. Likewise, OLN, suppresses GRP78 expression and impedes tumor growth in an orthotopic breast cancer xenograft model. Furthermore, OLN blocks infection by SARS-CoV-2 and its variants and enhances existing anti-viral therapies. Notably, GRP78 overexpression mitigates OLN-mediated cancer cell apoptotic onset and suppression of virus release. CONCLUSION: Our findings validate GRP78 as a target of OLN anti-cancer and anti-viral activities. These proof-of-principle studies support further investigation of OLN as a readily accessible compound to dually combat cancer and COVID-19.
RESUMO
The bacterial genotoxin colibactin promotes colorectal cancer (CRC) tumorigenesis, but systematic assessment of its impact on DNA repair is lacking, and its effect on response to DNA-damaging chemotherapeutics is unknown. We find that CRC cell lines display differential response to colibactin on the basis of homologous recombination (HR) proficiency. Sensitivity to colibactin is induced by inhibition of ATM, which regulates DNA double-strand break repair, and blunted by HR reconstitution. Conversely, CRC cells chronically infected with colibactin develop a tolerant phenotype characterized by restored HR activity. Notably, sensitivity to colibactin correlates with response to irinotecan active metabolite SN38, in both cell lines and patient-derived organoids. Moreover, CRC cells that acquire colibactin tolerance develop cross-resistance to SN38, and a trend toward poorer response to irinotecan is observed in a retrospective cohort of CRCs harboring colibactin genomic island. Our results shed insight into colibactin activity and provide translational evidence on its chemoresistance-promoting role in CRC.
Assuntos
Neoplasias Colorretais , Escherichia coli , Peptídeos , Policetídeos , Humanos , Irinotecano/farmacologia , Escherichia coli/genética , Escherichia coli/metabolismo , Estudos Retrospectivos , DNA/metabolismo , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Neoplasias Colorretais/microbiologiaRESUMO
Multiple strategies are continuously being explored to expand the drug target repertoire in solid tumors. We devised a novel computational workflow for transcriptome-wide gene expression outlier analysis that allows the systematic identification of both overexpression and underexpression events in cancer cells. Here, it was applied to expression values obtained through RNA sequencing in 226 colorectal cancer (CRC) cell lines that were also characterized by whole-exome sequencing and microarray-based DNA methylation profiling. We found cell models displaying an abnormally high or low expression level for 3533 and 965 genes, respectively. Gene expression abnormalities that have been previously associated with clinically relevant features of CRC cell lines were confirmed. Moreover, by integrating multi-omics data, we identified both genetic and epigenetic alternations underlying outlier expression values. Importantly, our atlas of CRC gene expression outliers can guide the discovery of novel drug targets and biomarkers. As a proof of concept, we found that CRC cell lines lacking expression of the MTAP gene are sensitive to treatment with a PRMT5-MTA inhibitor (MRTX1719). Finally, other tumor types may also benefit from this approach.
Assuntos
Neoplasias Colorretais , Regulação Neoplásica da Expressão Gênica , Transcriptoma , Humanos , Neoplasias Colorretais/genética , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/patologia , Neoplasias Colorretais/metabolismo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Linhagem Celular Tumoral , Transcriptoma/genética , Perfilação da Expressão Gênica , Metilação de DNA/genéticaRESUMO
The emergence of drug resistance is the most substantial challenge to the effectiveness of anticancer therapies. Orthogonal approaches have revealed that a subset of cells, known as drug-tolerant 'persister' (DTP) cells, have a prominent role in drug resistance. Although long recognized in bacterial populations which have acquired resistance to antibiotics, the presence of DTPs in various cancer types has come to light only in the past two decades, yet several aspects of their biology remain enigmatic. Here, we delve into the biological characteristics of DTPs and explore potential strategies for tracking and targeting them. Recent findings suggest that DTPs exhibit remarkable plasticity, being capable of transitioning between different cellular states, resulting in distinct DTP phenotypes within a single tumour. However, defining the biological features of DTPs has been challenging, partly due to the complex interplay between clonal dynamics and tissue-specific factors influencing their phenotype. Moreover, the interactions between DTPs and the tumour microenvironment, including their potential to evade immune surveillance, remain to be discovered. Finally, the mechanisms underlying DTP-derived drug resistance and their correlation with clinical outcomes remain poorly understood. This Roadmap aims to provide a comprehensive overview of the field of DTPs, encompassing past achievements and current endeavours in elucidating their biology. We also discuss the prospect of future advancements in technologies in helping to unveil the features of DTPs and propose novel therapeutic strategies that could lead to their eradication.
RESUMO
BACKGROUND: MET-driven acquired resistance is emerging with unanticipated frequency in patients relapsing upon molecular therapy treatments. However, the determination of MET amplification remains challenging using both standard and next-generation sequencing-based methodologies. Liquid biopsy is an effective, non-invasive approach to define cancer genomic profiles, track tumor evolution over time, monitor treatment response and detect molecular resistance in advance. Circular RNAs (circRNAs), a family of RNA molecules that originate from a process of back-splicing, are attracting growing interest as potential novel biomarkers for their stability in body fluids. METHODS: We identified a circRNA encoded by the MET gene (circMET) and exploited blood-derived cell-free RNA (cfRNA) and matched tumor tissues to identify, stratify and monitor advanced cancer patients molecularly characterized by high MET activity, generally associated with genomic amplification. RESULTS: Using publicly available bioinformatic tools, we discovered that the MET locus transcribes several circRNA molecules, but only one candidate, circMET, was particularly abundant. Deeper molecular analysis revealed that circMET levels positively correlated with MET expression and activity, especially in MET-amplified cells. We developed a circMET-detection strategy and, in parallel, we performed standard FISH and IHC analyses in the same specimens to assess whether circMET quantification could identify patients displaying high MET activity. Longitudinal monitoring of circMET levels in the plasma of selected patients revealed the early emergence of MET amplification as a mechanism of acquired resistance to molecular therapies. CONCLUSIONS: We found that measurement of circMET levels allows identification and tracking of patients characterized by high MET activity. Circulating circMET (ccMET) detection and analysis could be a simple, cost-effective, non-invasive approach to better implement patient stratification based on MET expression, as well as to dynamically monitor over time both therapy response and clonal evolution during treatment.
Assuntos
Neoplasias , RNA Circular , Humanos , Biomarcadores , Biologia Computacional , Neoplasias/genética , RNA/genética , RNA/metabolismo , RNA Circular/genéticaRESUMO
Compelling evidence shows that cancer persister cells represent a major limit to the long-term efficacy of targeted therapies. However, the phenotype and population dynamics of cancer persister cells remain unclear. We developed a quantitative framework to study persisters by combining experimental characterization and mathematical modeling. We found that, in colorectal cancer, a fraction of persisters slowly replicates. Clinically approved targeted therapies induce a switch to drug-tolerant persisters and a temporary 7- to 50-fold increase of their mutation rate, thus increasing the number of persister-derived resistant cells. These findings reveal that treatment may influence persistence and mutability in cancer cells and pinpoint inhibition of error-prone DNA polymerases as a strategy to restrict tumor recurrence.
Assuntos
Neoplasias Colorretais , Taxa de Mutação , Antibacterianos/farmacologia , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Humanos , Dinâmica PopulacionalRESUMO
Mutations in oncogenes and tumor suppressor genes are responsible for tumorigenesis and represent favored therapeutic targets in oncology. We exploited homologous recombination to knock-in individual cancer mutations in the genome of nontransformed human cells. Sequential introduction of multiple mutations was also achieved, demonstrating the potential of this strategy to construct tumor progression models. Knock-in cells displayed allele-specific activation of signaling pathways and mutation-specific phenotypes different from those obtainable by ectopic oncogene expression. Profiling of a library of pharmacological agents on the mutated cells showed striking sensitivity or resistance phenotypes to pathway-targeted drugs, often matching those of tumor cells carrying equivalent cancer mutations. Thus, knock-in of single or multiple cancer alleles provides a pharmacogenomic platform for the rational design of targeted therapies.
Assuntos
Alelos , Antineoplásicos/farmacologia , Regulação Neoplásica da Expressão Gênica/genética , Técnicas de Introdução de Genes , Genes Supressores de Tumor , Mutação , Neoplasias/tratamento farmacológico , Neoplasias/genética , Antineoplásicos/uso terapêutico , Linhagem Celular , Sistemas de Liberação de Medicamentos/métodos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Modelos BiológicosRESUMO
Cancer is characterized by loss of the regulatory mechanisms that preserve homeostasis in multicellular organisms, such as controlled proliferation, cell-cell adhesion, and tissue differentiation. The breakdown of multicellularity rules is accompanied by activation of "selfish," unicellular-like life features, which are linked to the increased adaptability to environmental changes displayed by cancer cells. Mechanisms of stress response, resembling those observed in unicellular organisms, are actively exploited by mammalian cancer cells to boost genetic diversity and increase chances of survival under unfavorable conditions, such as lack of oxygen/nutrients or exposure to drugs. Unicellular organisms under stressful conditions (e.g., antibiotic treatment) stop replicating or slowly divide and transiently increase their mutation rates to foster diversity, a process known as adaptive mutability. Analogously, tumor cells exposed to drugs enter a persister phenotype and can reduce DNA replication fidelity, which in turn fosters genetic diversity. The implications of adaptive evolution are of relevance to understand resistance to anticancer therapies.
Assuntos
Bactérias , Evolução Biológica , Homeostase , Neoplasias , HumanosRESUMO
Nociceptin/orphanin FQ (N/OFQ), the endogenous ligand for the N/OFQ peptide receptor (NOP), inhibits tachykinin release in the airway of several animal models. The aim of this study was to investigate the role of the N/OFQ-NOP receptor system in bronchoconstriction induced by sensory nerve activation in the isolated mouse lung. We used C57BL/6J NOP(+/+), NOP(-/-), and Balb/C mice sensitized (or not) to ovalbumin. Bronchopulmonary function coupled with measurements of endogenous N/OFQ levels before and after capsaicin-induced bronchoconstriction in the presence or absence of NOP-selective agonists/antagonists are presented. N/OFQ significantly inhibited capsaicin-induced bronchoconstriction in both naive and sensitized mice, these latter animals displaying airway hyperresponsiveness to capsaicin. The inhibitory effect of N/OFQ were not observed in NOP(-/-) mice, and were mimicked/abolished by the selective NOP agonist/antagonist University of Ferrara Peptide (UFP)-112/UFP-101 in NOP(+/+) mice. UFP-101 alone potentiated the effect of capsaicin in naive mice, but not in sensitized mice. Endogenous N/OFQ levels significantly decreased in sensitized mice relative to naive mice. We have demonstrated that a reduction in endogenous N/OFQ, or the lack of its receptor, causes an increase in capsaicin-induced bronchoconstriction, implying a role for the N/OFQ-NOP receptor system in the modulation of capsaicin effects. Moreover, for the first time, we document differential airway responsiveness to capsaicin between naive and sensitized mice due, at least in part, to decreased endogenous N/OFQ levels in sensitized mice.
Assuntos
Broncoconstrição/fisiologia , Pulmão/inervação , Pulmão/fisiologia , Peptídeos Opioides/fisiologia , Células Receptoras Sensoriais/fisiologia , Alérgenos/administração & dosagem , Animais , Broncoconstrição/efeitos dos fármacos , Broncoconstrição/imunologia , Capsaicina/farmacologia , Técnicas In Vitro , Pulmão/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Peptídeos Opioides/deficiência , Peptídeos Opioides/genética , Ovalbumina/administração & dosagem , Ovalbumina/imunologia , Receptores Opioides/fisiologia , Receptor de Nociceptina , NociceptinaRESUMO
PURPOSE: Defects in the homologous recombination (HR) repair pathway are of clinical interest due to sensitivity of HR-deficient cells to PARP inhibitors. We were interested in defining PARP vulnerability in patients with metastatic colorectal cancer (mCRC) carrying KRAS and BRAF mutations who display poor prognosis, have limited therapeutic options, and represent an unmet clinical need. EXPERIMENTAL DESIGN: We tested colorectal cancer cell lines, patient-derived organoids (PDO), and patient-derived xenografts (PDX) enriched for KRAS and BRAF mutations for sensitivity to the PARP inhibitor olaparib, and the chemotherapeutic agents oxaliplatin and 5-fluorouracil (5-FU). Genomic profiles and DNA repair proficiency of colorectal cancer models were compared with pharmacologic response. RESULTS: Thirteen of 99 (around 13%) colorectal cancer cell lines were highly sensitive to clinically active concentrations of olaparib and displayed functional deficiency in HR. Response to PARP blockade was positively correlated with sensitivity to oxaliplatin in colorectal cancer cell lines as well as patient-derived organoids. Treatment of PDXs with olaparib impaired tumor growth and maintenance therapy with PARP blockade after initial oxaliplatin response delayed disease progression in mice. CONCLUSIONS: These results indicate that a colorectal cancer subset characterized by poor prognosis and limited therapeutic options is vulnerable to PARP inhibition and suggest that PDO-based drug-screening assays can be used to identify patients with colorectal cancer likely to benefit from olaparib. As patients with mCRC almost invariably receive therapies based on oxaliplatin, "maintenance" treatment with PARP inhibitors warrants further clinical investigation.
Assuntos
Neoplasias Colorretais/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos , Regulação Neoplásica da Expressão Gênica , Oxaliplatina/farmacologia , Ftalazinas/farmacologia , Piperazinas/farmacologia , Reparo de DNA por Recombinação , Animais , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Humanos , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Mutação , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas p21(ras)/genética , Resultado do Tratamento , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
The emergence of drug resistance limits the efficacy of targeted therapies in human tumors. The prevalent view is that resistance is a fait accompli: when treatment is initiated, cancers already contain drug-resistant mutant cells. Bacteria exposed to antibiotics transiently increase their mutation rates (adaptive mutability), thus improving the likelihood of survival. We investigated whether human colorectal cancer (CRC) cells likewise exploit adaptive mutability to evade therapeutic pressure. We found that epidermal growth factor receptor (EGFR)/BRAF inhibition down-regulates mismatch repair (MMR) and homologous recombination DNA-repair genes and concomitantly up-regulates error-prone polymerases in drug-tolerant (persister) cells. MMR proteins were also down-regulated in patient-derived xenografts and tumor specimens during therapy. EGFR/BRAF inhibition induced DNA damage, increased mutability, and triggered microsatellite instability. Thus, like unicellular organisms, tumor cells evade therapeutic pressures by enhancing mutability.
Assuntos
Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Reparo de Erro de Pareamento de DNA/genética , Resistencia a Medicamentos Antineoplásicos/genética , Receptores ErbB/antagonistas & inibidores , Terapia de Alvo Molecular , Mutagênese , Proteínas Proto-Oncogênicas B-raf/antagonistas & inibidores , Adaptação Biológica/genética , Regulação para Baixo , Humanos , Seleção GenéticaRESUMO
Attempts at eradicating metastatic cancers with targeted therapies are limited by the emergence of resistant subclones bearing heterogeneous (epi)genetic changes. We used colorectal cancer (CRC) to test the hypothesis that interfering with an ancestral oncogenic event shared by all the malignant cells (such as WNT pathway alterations) could override heterogeneous mechanisms of acquired drug resistance. Here, we report that in CRC-resistant cell populations, phylogenetic analysis uncovers a complex subclonal architecture, indicating parallel evolution of multiple independent cellular lineages. Functional and pharmacological modulation of WNT signalling induces cell death in CRC preclinical models from patients that relapsed during the treatment, regardless of the drug type or resistance mechanisms. Concomitant blockade of WNT and MAPK signalling restrains the emergence of drug-resistant clones. Reliance upon the WNT-APC pathway is preserved throughout the branched genomic drift associated with emergence of treatment relapse, thus offering the possibility of a common therapeutic strategy to overcome secondary drug resistance.
Assuntos
Neoplasias Colorretais/genética , Deriva Genética , Terapia de Alvo Molecular , Mutação , Animais , Biópsia , Técnicas de Cultura de Células , Linhagem da Célula , Proliferação de Células , Neoplasias Colorretais/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos/genética , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Sistema de Sinalização das MAP Quinases , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Metástase Neoplásica , Recidiva Local de Neoplasia , Transplante de Neoplasias , Oncogenes , Filogenia , Transdução de Sinais , Via de Sinalização WntRESUMO
Targeting HER2 is effective in 24% of ERBB2 amplified metastatic colorectal cancer; however, secondary resistance occurs in most of the cases. We studied the evolution of individual metastases during treatment to discover spatially resolved determinants of resistance. Circulating tumor DNA (ctDNA) analysis identified alterations associated with resistance in the majority of refractory patients. ctDNA profiles and lesion-specific radiographic reports revealed organ- or metastasis-private evolutionary patterns. When radiologic assessments documented progressive disease in target lesions, response to HER2 blockade was retained in other metastases. Genomic and functional analyses on samples and cell models from eight metastases of a patient co-recruited to a postmortem study unveiled lesion-specific evolutionary trees and pharmacologic vulnerabilities. Lesion size and contribution of distinct metastases to plasma ctDNA were correlated.
Assuntos
Adenocarcinoma/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos/genética , Lapatinib/administração & dosagem , Neoplasias Hepáticas/tratamento farmacológico , Inibidores de Proteínas Quinases/administração & dosagem , Receptor ErbB-2/antagonistas & inibidores , Tomografia Computadorizada por Raios X , Trastuzumab/administração & dosagem , Adenocarcinoma/diagnóstico por imagem , Adenocarcinoma/genética , Adenocarcinoma/secundário , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Classe I de Fosfatidilinositol 3-Quinases/genética , Tomada de Decisão Clínica , Neoplasias Colorretais/diagnóstico por imagem , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Análise Mutacional de DNA , Progressão da Doença , Feminino , Amplificação de Genes , Humanos , Itália , Lapatinib/efeitos adversos , Biópsia Líquida , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/secundário , Imageamento por Ressonância Magnética , Masculino , Camundongos Endogâmicos NOD , Camundongos SCID , Camundongos Transgênicos , Valor Preditivo dos Testes , Intervalo Livre de Progressão , Inibidores de Proteínas Quinases/efeitos adversos , Receptor ErbB-2/genética , Fatores de Risco , Transdução de Sinais/efeitos dos fármacos , Fatores de Tempo , Trastuzumab/efeitos adversos , Resultado do Tratamento , Células Tumorais Cultivadas , Proteínas ras/genéticaRESUMO
Precision oncology relies on targeted drugs, such as kinase inhibitors, that are presently administered based on molecular profiles obtained from surgical or bioptic tissue samples. The inherent ability of human tumors to molecularly evolve in response to drug pressures represents a daunting diagnostic challenge. Circulating free DNA (cfDNA) released from primary and metastatic lesions can be used to draw molecular maps that can be continuously updated to match each tumor's evolution. We will present evidence that liquid biopsies can effectively interrogate how targeted therapies drive lesion-specific drug-resistance mechanisms. The impact of drug-induced molecular heterogeneity on subsequent lines of treatment will also be discussed.
Assuntos
Antineoplásicos/uso terapêutico , Neoplasias/tratamento farmacológico , Neoplasias/patologia , DNA de Neoplasias/genética , Resistencia a Medicamentos Antineoplásicos/genética , Humanos , Biópsia Líquida/métodos , MutaçãoRESUMO
The literature on immunosenescence has focused mainly on T cell impairment. With the aim of gaining insight into B cell immunosenescence, we investigated the serum immunoglobulin levels in a cohort of 166 subjects (20-106 years). Serum IgG (and IgG subclasses) were quantified by the nephelometric technique, IgE by CAP system fluorescence enzyme immunoassay, and IgD by radial immunodiffusion (RID). There was an age-related increase of IgG and IgA; the IgG age-related increase was significant only in men, but IgG1 levels showed an age-related increase both in men and women, whereas IgG3 showed an age-related increase only in men. IgE levels remain unchanged, whereas IgD and IgM serum levels decreased with age; the IgM age-related decrease was significant only in women, likely due to the relatively small sample of aged men. Thus, in the elderly the B cell repertoire available to respond to new antigenic challenge is decreased. A lot of memory IgD- B cells are filling immunological space and the amount of naïve IgD+ B cells is dramatically decreased. This shift away from a population of predominantly naïve B cells obviously reflects the influences of cumulative exposure to foreign pathogens over time. These age-dependent B cell changes indicate that advanced age is a condition characterized by lack of clonotypic immune response to new extracellular pathogens. In any event, the increase of memory B cells and the loss of naïve B cells, as measured by serum IgD levels, could represent hallmarks of immunosenescence and could provide useful biomarkers possibly related to the life span of humans.
Assuntos
Linfócitos B/imunologia , Imunoglobulinas/sangue , Longevidade/imunologia , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Feminino , Humanos , Memória Imunológica , MasculinoRESUMO
UNLABELLED: Entrectinib is a first-in-class pan-TRK kinase inhibitor currently undergoing clinical testing in colorectal cancer and other tumor types. A patient with metastatic colorectal cancer harboring an LMNA-NTRK1 rearrangement displayed a remarkable response to treatment with entrectinib, which was followed by the emergence of resistance. To characterize the molecular bases of the patient's relapse, circulating tumor DNA (ctDNA) was collected longitudinally during treatment, and a tissue biopsy, obtained before entrectinib treatment, was transplanted in mice (xenopatient), which then received the same entrectinib regimen until resistance developed. Genetic profiling of ctDNA and xenopatient samples showed acquisition of two point mutations in the catalytic domain of NTRK1, p.G595R and p.G667C. Biochemical and pharmacologic analysis in multiple preclinical models confirmed that either mutation renders the TRKA kinase insensitive to entrectinib. These findings can be immediately exploited to design next-generation TRKA inhibitors. SIGNIFICANCE: We provide proof of principle that analyses of xenopatients (avatar) and liquid biopsies allow the identification of drug resistance mechanisms in parallel with clinical treatment of an individual patient. We describe for the first time that p.G595R and p.G667C TRKA mutations drive acquired resistance to entrectinib in colorectal cancers carrying NTRK1 rearrangements.