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1.
JHEP Rep ; 5(4): 100672, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36866388

RESUMEN

Background & Aims: We elucidated the clinical and immunologic implications of serum IL-6 levels in patients with unresectable hepatocellular carcinoma (HCC) treated with atezolizumab and bevacizumab (Ate/Bev). Methods: We prospectively enrolled 165 patients with unresectable HCC (discovery cohort: 84 patients from three centres; validation cohort: 81 patients from one centre). Baseline blood samples were analysed using a flow cytometric bead array. The tumour immune microenvironment was analysed using RNA sequencing. Results: In the discovery cohort, clinical benefit 6 months (CB6m) was defined as complete or partial response, or stable disease for ≥6 months. Among various blood-based biomarkers, serum IL-6 levels were significantly higher in participants without CB6m than in those with CB6m (mean 11.56 vs. 5.05 pg/ml, p = 0.02). Using maximally selected rank statistics, the optimal cut-off value for high IL-6 was determined as 18.49 pg/ml, and 15.2% of participants were found to have high IL-6 levels at baseline. In both the discovery and validation cohorts, participants with high baseline IL-6 levels had a reduced response rate and worse progression-free and overall survival after Ate/Bev treatment compared with those with low baseline IL-6 levels. In multivariable Cox regression analysis, the clinical implications of high IL-6 levels persisted, even after adjusting for various confounding factors. Participants with high IL-6 levels showed reduced interferon-γ and tumour necrosis factor-α secretion from CD8+ T cells. Moreover, excess IL-6 suppressed cytokine production and proliferation of CD8+ T cells. Finally, participants with high IL-6 levels exhibited a non-T-cell-inflamed immunosuppressive tumour microenvironment. Conclusions: High baseline IL-6 levels can be associated with poor clinical outcomes and impaired T-cell function in patients with unresectable HCC after Ate/Bev treatment. Impact and implications: Although patients with hepatocellular carcinoma who respond to treatment with atezolizumab and bevacizumab exhibit favourable clinical outcomes, a fraction of these still experience primary resistance. We found that high baseline serum levels of IL-6 correlate with poor clinical outcomes and impaired T-cell response in patients with hepatocellular carcinoma treated with atezolizumab and bevacizumab.

2.
Front Immunol ; 14: 1114717, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36814910

RESUMEN

Background: Immunotherapy has been the first-line treatment option in advanced Hepatocellular Carcinoma(HCC); but now, there are no established molecular markers that can predict immunotherapy response. Estrogen has a crucial role in the development of a variety of liver illnesses, including liver fibrosis, Nonalcoholic fatty liver disease (NAFLD), and HCC. Nonetheless, the significance of estrogen-related genes in HCC immunotherapy and the underlying molecular mechanisms are not yet fully understood. Method: In this study, we constructed a novel estrogen-related gene prognostic signature (ERGPS) by analyzing bulk RNA sequencing data from 365 HCC patients. Based on the median risk score, we divided 365 HCC patients into low- and high-risk groups. Tumor mutation burden (TMB), Microsatellite instability (MSI), T cell receptor (TCR) richness, B cell receptor (BCR) richness, single-nucleotide variants (SNV) Neoantigens, Cancer Testicular Antigens (CTA) scores, and Tumour Immune Dysfunction and Exclusion (TIDE) scores were used to evaluate the magnitude of immunotherapy response. Multiple external datasets validate the validity and robustness of the prognostic signature. Real-time quantitative polymerase chain reaction (qRT-PCR) was used to validate estrogen-related gene overexpression in HCC tissue samples. Results: ERGPS is an independent risk factor affecting the prognosis of HCC patients and is superior to other clinical variables in predicting patient survival and immunotherapy response. Multiple independent external datasets confirmed the superior predictive efficacy of the prognostic signature. The prognostic signature was positively correlated with TMB score, MSI score, TCR richness, BCR richness, SNV Neoantigens score, CTA score, expression levels of immune checkpoint-related genes, and TIDE score. Patients with HCC in the high-risk group identified by the prognostic signature were likely to be more responsive to immunotherapy and more suitable for immunotherapy. qRT-PCR confirmed that estrogen-related genes of the construct signature were highly expressed in HCC tumor tissues. Conclusion: Estrogen-related genes are overexpressed in HCC tissues. Our novel prognostic signature can accurately predict not only the prognosis but also the immunotherapy response of HCC patients. In the future, prognostic signatures will be a useful tool for clinicians to screen patients with HCC who are suitable for immunotherapy.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Inmunoterapia , Estrógenos , Inestabilidad de Microsatélites
3.
Comput Struct Biotechnol J ; 20: 3106-3119, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35782736

RESUMEN

Shc SH2-domain binding protein 1 (SHCBP1), a protein specific binding to SH2 domain of Src homolog and collagen homolog (Shc), takes part in the regulation of various signal transduction pathways, which has been reported to be associated with tumorigenesis and progression. However, the pathological mechanisms are not completely investigated. Thus, this study aimed to comprehensively elucidate the potential functions of SHCBP1 in multiple cancer types. The comprehensive analyses for SHCBP1 in various tumors, including gene expression, diagnosis, prognosis, immune-related features, genetic alteration, and function enrichment, were conducted based on multiple databases and analysis tools. SHCBP1 was upregulated in most types of cancers. The results of qRT-PCR had confirmed that SHCBP1 mRNA was significantly upregulated in lung adenocarcinoma (LUAD) and liver hepatocellular carcinoma (LIHC) cell lines. Based on the receiver operating characteristic (ROC) and survival analysis, SHCBP1 was considered as a potential diagnostic and prognostic biomarker. Furthermore, SHCBP1 expression was linked with tumor immunity and immunosuppressive microenvironment according to the correlation analysis of SHCBP1 expression with immune cells infiltration, immune checkpoint genes, and immune-related genes (MHC genes, chemokines, and chemokines receptors). Moreover, SHCBP1 expression correlated with tumor mutational burden (TMB), microsatellite instability (MSI), and neoantigens. The feature of SHCBP1 mutational landscape in pan-cancer was identified. Finally, we focused on investigating the clinical significance and the potential biological role of SHCBP1 in LUAD. Our study comprehensively uncovered that SHCBP1 could be identified as an immune-related biomarker for cancer diagnosis and prognosis, and a potential therapeutic target for tumor immunotherapy.

4.
Comput Struct Biotechnol J ; 20: 3304-3312, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35782741

RESUMEN

The SARS-CoV-2 is constantly mutating, and the new coronavirus such as Omicron has spread to many countries around the world. Anexelekto (AXL) is a transmembrane protein with biological functions such as promoting cell growth, migration, aggregation, metastasis and adhesion, and plays an important role in cancers and coronavirus disease 2019 (COVID-19). Unlike angiotensin-converting enzyme 2 (ACE2), AXL was highly expressed in respiratory system cells. In this study, we verified the AXL expression in cancer and normal tissues and found AXL expression was strongly correlated with cancer prognosis, tumor mutation burden (TMB), the microsatellite instability (MSI) in most tumor types. Immune infiltration analysis also demonstrated that there was an inextricable link between AXL expression and immune scores in cancer patients, especially in BLCA, BRCA and CESC. The NK-cells, plasmacytoid dendritic cells, myeloid dendritic cells, as one of the important components of the tumor microenvironment, were highly expressed AXL. In addition, AXL-related tumor neoantigens were identified and might provide the novel potential targets for tumor vaccines or SARS-Cov-2 vaccines research in cancer patients.

5.
Comput Struct Biotechnol J ; 20: 3322-3335, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35832625

RESUMEN

Centrosome and spindle pole-associated protein (CSPP1) is a centrosome and microtubule-binding protein that plays a role in cell cycle-dependent cytoskeleton organization and cilia formation. Previous studies have suggested that CSPP1 plays a role in tumorigenesis; however, no pan-cancer analysis has been performed. This study systematically investigates the expression of CSPP1 and its potential clinical outcomes associated with diagnosis, prognosis, and therapy. CSPP1 is widely present in tissues and cells and its aberrant expression serves as a diagnostic biomarker for cancer. CSPP1 dysregulation is driven by multi-dimensional mechanisms involving genetic alterations, DNA methylation, and miRNAs. Phosphorylation of CSPP1 at specific sites may play a role in tumorigenesis. In addition, CSPP1 correlates with clinical features and outcomes in multiple cancers. Take brain low-grade gliomas (LGG) with a poor prognosis as an example, functional enrichment analysis implies that CSPP1 may play a role in ferroptosis and tumor microenvironment (TME), including regulating epithelial-mesenchymal transition, stromal response, and immune response. Further analysis confirms that CSPP1 dysregulates ferroptosis in LGG and other cancers, making it possible for ferroptosis-based drugs to be used in the treatment of these cancers. Importantly, CSPP1-associated tumors are infiltrated in different TMEs, rendering immune checkpoint blockade therapy beneficial for these cancer patients. Our study is the first to demonstrate that CSPP1 is a potential diagnostic and prognostic biomarker associated with ferroptosis and TME, providing a new target for drug therapy and immunotherapy in specific cancers.

6.
Acta Pharm Sin B ; 12(1): 149-166, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35127377

RESUMEN

Colorectal cancer (CRC), a malignant tumor worldwide consists of microsatellite instability (MSI) and stable (MSS) phenotypes. Although SHP2 is a hopeful target for cancer therapy, its relationship with innate immunosuppression remains elusive. To address that, single-cell RNA sequencing was performed to explore the role of SHP2 in all cell types of tumor microenvironment (TME) from murine MC38 xenografts. Intratumoral cells were found to be functionally heterogeneous and responded significantly to SHP099, a SHP2 allosteric inhibitor. The malignant evolution of tumor cells was remarkably arrested by SHP099. Mechanistically, STING-TBK1-IRF3-mediated type I interferon signaling was highly activated by SHP099 in infiltrated myeloid cells. Notably, CRC patients with MSS phenotype exhibited greater macrophage infiltration and more potent SHP2 phosphorylation in CD68+ macrophages than MSI-high phenotypes, suggesting the potential role of macrophagic SHP2 in TME. Collectively, our data reveals a mechanism of innate immunosuppression mediated by SHP2, suggesting that SHP2 is a promising target for colon cancer immunotherapy.

7.
JACC CardioOncol ; 4(5): 579-597, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36636451

RESUMEN

Immune checkpoint inhibitors (ICIs) are a major class of immuno-oncology therapeutics that have significantly improved the prognosis of various cancers, both in (neo)adjuvant and metastatic settings. Unlike other conventional therapies, ICIs elicit antitumor effects by enhancing host immune systems to eliminate cancer cells. There are 3 approved ICI classes by the U.S. Food and Drug Administration: inhibitors targeting cytotoxic T lymphocyte associated antigen 4, programmed death 1/programmed death-ligand 1, and lymphocyte-activation gene 3, with many more in development. ICIs are commonly associated with distinct toxicities, known as immune-related adverse events, which can arise during treatment or less frequently be of late onset, usually relating to excessive activation of the immune system. Acute cardiovascular immune-related adverse events such as myocarditis are rare; however, data suggesting chronic cardiovascular sequelae are emerging. This review presents the current landscape of ICIs in oncology, with a focus on important aspects relevant to cardiology.

8.
Acta Pharm Sin B ; 11(10): 2983-2994, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34729299

RESUMEN

Genomic instability remains an enabling feature of cancer and promotes malignant transformation. Alterations of DNA damage response (DDR) pathways allow genomic instability, generate neoantigens, upregulate the expression of programmed death ligand 1 (PD-L1) and interact with signaling such as cyclic GMP-AMP synthase-stimulator of interferon genes (cGAS-STING) signaling. Here, we review the basic knowledge of DDR pathways, mechanisms of genomic instability induced by DDR alterations, impacts of DDR alterations on immune system, and the potential applications of DDR alterations as biomarkers and therapeutic targets in cancer immunotherapy.

9.
IUBMB Life ; 73(5): 726-738, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33686787

RESUMEN

The importance of the tumor microenvironment in cancer progression has been well studied for many years. Immune checkpoint inhibitors (ICIs) are regarded as potential strategies in enhancing the immune responses in patients with cancer, particularly colorectal cancer (CRC). Notably, CRCs are extraordinarily heterogeneous and mostly are microsatellite-stable (MSS) or cold tumors, which means that the immune response is not usually as strong as that of foreign cells. T-cell immunoglobulin and ITIM domain (TIGIT) is a new immune checkpoint receptor overexpressed inside the CRC tumor-immune microenvironments. Moreover, several studies have shown that TIGIT in combination with other ICIs and/or conventional treatments, can lead to a robust anti-tumor response in CRC. This review looks deep inside TIGIT expression patterns, their various functions, and possible immunotherapy strategies to increase survival rates and decrease immune-related adverse events.


Asunto(s)
Adenocarcinoma/terapia , Neoplasias Colorrectales/terapia , Inhibidores de Puntos de Control Inmunológico , Proteínas de Punto de Control Inmunitario/inmunología , Inmunoterapia/métodos , Receptores Inmunológicos/antagonistas & inhibidores , Adenocarcinoma/inmunología , Adenocarcinoma/patología , Secuencias de Aminoácidos , Animales , Antígenos CD/inmunología , Sistemas CRISPR-Cas , Neoplasias Colorrectales/inmunología , Neoplasias Colorrectales/patología , Neoplasias Colorrectales/radioterapia , Terapia Combinada , Microbioma Gastrointestinal , Regulación Neoplásica de la Expresión Génica , Humanos , Ratones , Pronóstico , Dominios Proteicos , Receptores Inmunológicos/biosíntesis , Receptores Inmunológicos/deficiencia , Receptores Inmunológicos/genética , Receptores Inmunológicos/inmunología , Microambiente Tumoral
10.
Comput Struct Biotechnol J ; 18: 668-675, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32257050

RESUMEN

Microsatellite instability (MSI) is a genomic property of the cancers with defective DNA mismatch repair and is a useful marker for cancer diagnosis and treatment in diverse cancer types. In particular, MSI has been associated with the active immune checkpoint blockade therapy response in cancer. Most of computational methods for predicting MSI are based on DNA sequencing data and a few are based on mRNA expression data. Using the RNA-Seq pan-cancer datasets for three cancer cohorts (colon, gastric, and endometrial cancers) from The Cancer Genome Atlas (TCGA) program, we developed an algorithm (PreMSIm) for predicting MSI from the expression profiling of a 15-gene panel in cancer. We demonstrated that PreMSIm had high prediction performance in predicting MSI in most cases using both RNA-Seq and microarray gene expression datasets. Moreover, PreMSIm displayed superior or comparable performance versus other DNA or mRNA-based methods. We conclude that PreMSIm has the potential to provide an alternative approach for identifying MSI in cancer.

11.
Comput Struct Biotechnol J ; 17: 447-453, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31007870

RESUMEN

In this review we aim to summarize studies investigating the impact of a molecular profiling (MP)-guided treatment approach in heavily pretreated cancer patients. In summary, many independent single- and multicenter studies showed a significant benefit of MP-guided treatment regarding response rates and survival. However, in the only randomized trial conducted so far, no benefit of MP-guided targeted therapy was observed. Notably, various profiling approaches were conducted in the respective studies: some studies used a single analytic approach (i.e. next-generation sequencing), others applied multiple analytic methods to perform comprehensive molecular profiling. It seems that multiplatform profiling analyses, detected an increased number of druggable molecular targets or signaling pathway alterations and that a higher proportion of patients was treated according to the molecular cancer profile. Even though no randomized study has shown a benefit of molecular profiling so far, many studies indicate that MP-guided treatment can be beneficial in patients with relapsed and/or refractory cancer. Currently ongoing large randomized trials (i.e. NCI-MATCH, TAPUR) will add evidence to the role of profiling-guided cancer treatment.

12.
Cell Mol Gastroenterol Hepatol ; 6(3): 277-300, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30116770

RESUMEN

Background & Aims: Recent studies have shown that cancers arise as a result of the positive selection of driver somatic events in tumor DNA, with negative selection playing only a minor role, if any. However, these investigations were concerned with alterations at nonrepetitive sequences and did not take into account mutations in repetitive sequences that have very high pathophysiological relevance in the tumors showing microsatellite instability (MSI) resulting from mismatch repair deficiency investigated in the present study. Methods: We performed whole-exome sequencing of 47 MSI colorectal cancers (CRCs) and confirmed results in an independent cohort of 53 MSI CRCs. We used a probabilistic model of mutational events within microsatellites, while adapting pre-existing models to analyze nonrepetitive DNA sequences. Negatively selected coding alterations in MSI CRCs were investigated for their functional and clinical impact in CRC cell lines and in a third cohort of 164 MSI CRC patients. Results: Both positive and negative selection of somatic mutations in DNA repeats was observed, leading us to identify the expected true driver genes associated with the MSI-driven tumorigenic process. Several coding negatively selected MSI-related mutational events (n = 5) were shown to have deleterious effects on tumor cells. In the tumors in which deleterious MSI mutations were observed despite the negative selection, they were associated with worse survival in MSI CRC patients (hazard ratio, 3; 95% CI, 1.1-7.9; P = .03), suggesting their anticancer impact should be offset by other as yet unknown oncogenic processes that contribute to a poor prognosis. Conclusions: The present results identify the positive and negative driver somatic mutations acting in MSI-driven tumorigenesis, suggesting that genomic instability in MSI CRC plays a dual role in achieving tumor cell transformation. Exome sequencing data have been deposited in the European genome-phenome archive (accession: EGAS00001002477).


Asunto(s)
Carcinogénesis/genética , Neoplasias Colorrectales/genética , Inestabilidad de Microsatélites , Mutación/genética , Secuencias Repetitivas de Ácidos Nucleicos/genética , Animales , Secuencia de Bases , Línea Celular Tumoral , Estudios de Cohortes , Femenino , Xenoinjertos , Humanos , Masculino , Ratones , Ratones Desnudos , Modelos Estadísticos , Secuenciación del Exoma
14.
Cell Mol Gastroenterol Hepatol ; 3(2): 163-173, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28275683

RESUMEN

In patients with colorectal cancer (CRC) that metastasizes to the liver, there are several key goals for improving outcomes including early detection, effective prognostic indicators of treatment response, and accurate identification of patients at high risk for recurrence. Although new therapeutic regimens developed over the past decade have increased survival, there is substantial room for improvement in selecting targeted treatment regimens for the patients who will derive the most benefit. Recently, there have been exciting developments in identifying high-risk patient cohorts, refinements in the understanding of systemic vs localized drug delivery to metastatic niches, liquid biomarker development, and dramatic advances in tumor immune therapy, all of which promise new and innovative approaches to tackling the problem of detecting and treating the metastatic spread of CRC to the liver. Our multidisciplinary group held a state-of-the-science symposium this past year to review advances in this rapidly evolving field. Herein, we present a discussion around the issues facing treatment of patients with CRC liver metastases, including the relationship of discrete gene signatures with prognosis. We also discuss the latest advances to maximize regional and systemic therapies aimed at decreasing intrahepatic recurrence, review recent insights into the tumor microenvironment, and summarize advances in noninvasive multimodal biomarkers for early detection of primary and recurrent disease. As we continue to advance clinically and technologically in the field of colorectal tumor biology, our goal should be continued refinement of predictive and prognostic studies to decrease recurrence after curative resection and minimize treatment toxicity to patients through a tailored multidisciplinary approach to cancer care.

15.
Cell Mol Gastroenterol Hepatol ; 3(2): 211-217, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28275688

RESUMEN

Advancement in the field of cancer genomics is revolutionizing the molecular characterization of a wide variety of different cancers. Recent application of large-scale, next-generation sequencing technology to gastric cancer, which remains a major source of morbidity and mortality throughout the world, has helped better define the complex genomic landscape of this cancer. These studies also have led to the development of novel genomically based molecular classification systems for gastric cancer, reinforced the importance of classic driver mutations in gastric cancer pathogenesis, and led to the discovery of new driver gene mutations that previously were not known to be associated with gastric cancer. This wealth of genomic data has significant potential to impact the future management of this disease, and the challenge remains to effectively translate this genomic data into better treatment paradigms for gastric cancer.

16.
Cell Mol Gastroenterol Hepatol ; 1(2): 131-153, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28210673

RESUMEN

Gastroenteropancreatic neuroendocrine neoplasms (GEP-NEN), considered a heterogeneous neoplasia, exhibit ill-defined pathobiology and protean symptomatology and are ubiquitous in location. They are difficult to diagnose, challenging to manage, and outcome depends on cell type, secretory product, histopathologic grading, and organ of origin. A morphologic and molecular genomic review of these lesions highlights tumor characteristics that can be used clinically, such as somatostatin-receptor expression, and confirms features that set them outside the standard neoplasia paradigm. Their unique pathobiology is useful for developing diagnostics using somatostatin-receptor targeted imaging or uptake of radiolabeled amino acids specific to secretory products or metabolism. Therapy has evolved via targeting of protein kinase B signaling or somatostatin receptors with drugs or isotopes (peptide-receptor radiotherapy). With DNA sequencing, rarely identified activating mutations confirm that tumor suppressor genes are relevant. Genomic approaches focusing on cancer-associated genes and signaling pathways likely will remain uninformative. Their uniquely dissimilar molecular profiles mean individual tumors are unlikely to be easily or uniformly targeted by therapeutics currently linked to standard cancer genetic paradigms. The prevalence of menin mutations in pancreatic NEN and P27KIP1 mutations in small intestinal NEN represents initial steps to identifying a regulatory commonality in GEP-NEN. Transcriptional profiling and network-based analyses may define the cellular toolkit. Multianalyte diagnostic tools facilitate more accurate molecular pathologic delineations of NEN for assessing prognosis and identifying strategies for individualized patient treatment. GEP-NEN remain unique, poorly understood entities, and insight into their pathobiology and molecular mechanisms of growth and metastasis will help identify the diagnostic and therapeutic weaknesses of this neoplasia.

17.
Epigenetics ; 9(11): 1454-60, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25496513

RESUMEN

The CpG Island Methylator Phenotype (CIMP) is fundamental to an important subset of colorectal cancer; however, its cause is unknown. CIMP is associated with microsatellite instability but is also found in BRAF mutant microsatellite stable cancers that are associated with poor prognosis. The isocitrate dehydrogenase 1 (IDH1) gene causes CIMP in glioma due to an activating mutation that produces the 2-hydroxyglutarate oncometabolite. We therefore examined IDH1 alteration as a potential cause of CIMP in colorectal cancer. The IDH1 mutational hotspot was screened in 86 CIMP-positive and 80 CIMP-negative cancers. The entire coding sequence was examined in 81 CIMP-positive colorectal cancers. Forty-seven cancers varying by CIMP-status and IDH1 mutation status were examined using Illumina 450K DNA methylation microarrays. The R132C IDH1 mutation was detected in 4/166 cancers. All IDH1 mutations were in CIMP cancers that were BRAF mutant and microsatellite stable (4/45, 8.9%). Unsupervised hierarchical cluster analysis identified an IDH1 mutation-like methylation signature in approximately half of the CIMP-positive cancers. IDH1 mutation appears to cause CIMP in a small proportion of BRAF mutant, microsatellite stable colorectal cancers. This study provides a precedent that a single gene mutation may cause CIMP in colorectal cancer, and that this will be associated with a specific epigenetic signature and clinicopathological features.


Asunto(s)
Neoplasias Colorrectales/genética , Islas de CpG , Isocitrato Deshidrogenasa/genética , Mutación , Anciano , Anciano de 80 o más Años , Análisis por Conglomerados , Metilación de ADN , Femenino , Humanos , Masculino , Inestabilidad de Microsatélites , Persona de Mediana Edad , Fenotipo
18.
Cell Cycle ; 13(17): 2697-706, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25486357

RESUMEN

Enzastaurin is a selective inhibitor of protein kinase C ß and a potent inhibitor of tumor angiogenesis. In addition, enzastaurin shows direct cytotoxic activity toward a subset of tumor cells including colorectal cancer cells (CRC). In spite of promising results in animal models, the clinical activity of enzastaurin in CRC patients has been disappointing although a subset of patients seems to derive benefit. In the present study we investigated the biological and cytotoxic activities of enzastaurin toward a panel of well-characterized CRC cell lines in order to clarify the mechanistic basis for the cytotoxic activity. Our results show that enzastaurin is significantly more cytotoxic toward CRC cells with chromosome instability (CIN) compared to cells with microsatellite instability (MSI). Since CIN is usually attributed to mitotic dysfunction, the influence of enzastaurin on cell cycle progression and mitotic transit was characterized for representative CIN and MSI cell lines. Enzastaurin exposure was accompanied by prolonged metaphase arrest in CIN cells followed by the appearance of tetraploid and micronuclei-containing cells as well as by increased apoptosis, whereas no detectable mitotic dysfunctions were observed in MSI cells exposed to isotoxic doses of enzastaurin. Our study identifies enzastaurin as a new, context dependent member of a heterogeneous group of anticancer compounds that induce "mitotic catastrophe," that is mitotic dysfunction accompanied by cell death. These data provide novel insight into the mechanism of action of enzastaurin and may allow the identification of biomarkers useful to identify CRC patients particularly likely, or not, to benefit from treatment with enzastaurin.


Asunto(s)
Inestabilidad Cromosómica/efectos de los fármacos , Segregación Cromosómica/efectos de los fármacos , Neoplasias Colorrectales/patología , Indoles/farmacología , Mitosis/efectos de los fármacos , Proteína Quinasa C beta/antagonistas & inhibidores , Puntos de Control del Ciclo Celular/efectos de los fármacos , Muerte Celular/efectos de los fármacos , Línea Celular Tumoral , Centrosoma/efectos de los fármacos , Centrosoma/metabolismo , Humanos , Metafase/efectos de los fármacos , Poliploidía , Proteína Quinasa C beta/metabolismo , Proteína p53 Supresora de Tumor/metabolismo
19.
Epigenetics ; 9(10): 1431-8, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25437057

RESUMEN

Lynch syndrome (LS) is a tumor predisposing condition caused by constitutional defects in genes coding for components of the mismatch repair (MMR) apparatus. While hypermethylation of the promoter of the MMR gene MLH1 occurs in about 15% of colorectal cancer samples, it has also been observed as a constitutional alteration, in the absence of DNA sequence mutations, in a small number of LS patients. In order to obtain further insights on the phenotypic characteristics of MLH1 epimutation carriers, we investigated the somatic and constitutional MLH1 methylation status of 14 unrelated subjects with a suspicion of LS who were negative for MMR gene constitutional mutations and whose tumors did not express the MLH1 protein. A novel case of constitutional MLH1 epimutation was identified. This patient was affected with multiple primary tumors, including breast cancer, diagnosed starting from the age of 55 y. Investigation of her offspring by allele specific expression revealed that the epimutation was not stable across generations. We also found MLH1 hypermethylation in cancer samples from 4 additional patients who did not have evidence of constitutional defects. These patients had some characteristics of LS, namely early age at onset and/or positive family history, raising the possibility of genetic influences in the establishment of somatic MLH1 methylation.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/genética , Neoplasias Colorrectales Hereditarias sin Poliposis/genética , Metilación de ADN , Proteínas Nucleares/genética , Adulto , Análisis Mutacional de ADN , Femenino , Humanos , Masculino , Persona de Mediana Edad , Homólogo 1 de la Proteína MutL , Linaje , Regiones Promotoras Genéticas
20.
Artículo en Coreano | WPRIM (Pacífico Occidental) | ID: wpr-17955

RESUMEN

Lynch syndrome is also called Hereditary nonpolyposis colorectal cancer (HNPCC). It is characterized by a risk of colorectal cancer and other cancers of the endometrium, ovary, stomach, small intestine etc. The increased risk is due to inherited mutations that impaired DNA mismatch repair. Two to three percentage of colon cancer is caused by Lynch syndrome. A family history of colon cancer occurs at a young age. We experienced one case of Lynch syndrome who had had stomach cancer, endometrial cancer and colon cancer recently. Hence we report this case with a brief review of literature.


Asunto(s)
Femenino , Humanos , Neoplasias del Colon , Neoplasias Colorrectales , Neoplasias Colorrectales Hereditarias sin Poliposis , Reparación de la Incompatibilidad de ADN , Neoplasias Endometriales , Endometrio , Intestino Delgado , Ovario , Estómago , Neoplasias Gástricas
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