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1.
BMB Rep ; 56(4): 216-224, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36945828

RESUMO

Centrosome abnormalities are hallmarks of human cancers. Structural and numerical centrosome abnormalities correlate with tumor aggressiveness and poor prognosis, implicating that centrosome abnormalities could be a cause of tumorigenesis. Since Boveri made his pioneering recognition of the potential causal link between centrosome abnormalities and cancer more than a century ago, there has been significant progress in the field. Here, we review recent advances in the understanding of the causes and consequences of centrosome abnormalities and their connection to cancers. Centrosome abnormalities can drive the initiation and progression of cancers in multiple ways. For example, they can generate chromosome instability through abnormal mitosis, accelerating cancer genome evolution. Remarkably, it is becoming clear that the mechanisms by which centrosome abnormalities promote several steps of tumorigenesis are far beyond what Boveri had initially envisioned. We highlight various cancer-promoting mechanisms exerted by cells with centrosome abnormalities and how these cells possessing oncogenic potential can be monitored. [BMB Reports 2023; 56(4): 216-224].


Assuntos
Neoplasias , Humanos , Neoplasias/genética , Centrossomo/patologia , Carcinogênese/patologia , Mitose , Transformação Celular Neoplásica/patologia
2.
J Thorac Oncol ; 17(4): 558-567, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34958928

RESUMO

INTRODUCTION: This integrated analysis of a phase 1/2 study (NCT03046992) evaluated the efficacy and safety of lazertinib, a third-generation EGFR tyrosine kinase inhibitor (TKI), in patients with advanced EGFR T790M-positive NSCLC after previous EGFR TKI therapy. METHODS: Adults with EGFR mutation-positive NSCLC that progressed after prior EGFR-directed TKIs received once daily oral lazertinib 240 mg continuously until disease progression. Prior TKIs to treat T790M-positive NSCLC were prohibited. Primary endpoints were safety and objective response rate (ORR). Secondary endpoints included progression-free survival, overall survival, and intracranial ORR. RESULTS: A total of 78 patients received lazertinib 240 mg at 17 centers in South Korea. Among patients with T790M-positive tumors at baseline (N = 76), one (1.3%) had a complete response and 41 (53.9%) had partial responses, giving an ORR of 55.3% (95% confidence interval [CI]: 44.1-66.4). Median progression-free survival was 11.1 months (95% CI: 5.5-16.4). Median overall survival was not reached (median follow-up = 22.0 mo). In patients with measurable intracranial lesions (n = 7), one (14.3%) had a complete intracranial response and five (71.4%) had partial responses, giving an intracranial ORR of 85.7% (95% CI: 59.8%-100.0%). The most common treatment-emergent adverse events were rash (37.2%), pruritus (34.6%), and paresthesia (33.3%); most were mild to moderate in severity. Serious drug-related adverse events occurred in three patients (gastritis, pneumonia, pneumonitis). The major mechanism of resistance was EGFR T790M loss. CONCLUSIONS: Lazertinib 240 mg/d has a manageable safety profile with durable antitumor efficacy, including brain metastases, in patients with advanced T790M-positive NSCLC after previous EGFR TKI therapy.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Adulto , Carcinoma Pulmonar de Células não Pequenas/induzido quimicamente , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Receptores ErbB/genética , Humanos , Neoplasias Pulmonares/induzido quimicamente , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Morfolinas , Mutação , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Pirazóis , Pirimidinas
3.
Cancer Res Commun ; 2(10): 1197-1213, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36860703

RESUMO

Lung adenocarcinoma (LUAD) is the major subtype in lung cancer, and cigarette smoking is essentially linked to its pathogenesis. We show that downregulation of Filamin A interacting protein 1-like (FILIP1L) is a driver of LUAD progression. Cigarette smoking causes its downregulation by promoter methylation in LUAD. Loss of FILIP1L increases xenograft growth, and, in lung-specific knockout mice, induces lung adenoma formation and mucin secretion. In syngeneic allograft tumors, reduction of FILIP1L and subsequent increase in its binding partner, prefoldin 1 (PFDN1) increases mucin secretion, proliferation, inflammation, and fibrosis. Importantly, from the RNA-sequencing analysis of these tumors, reduction of FILIP1L is associated with upregulated Wnt/ß-catenin signaling, which has been implicated in proliferation of cancer cells as well as inflammation and fibrosis within the tumor microenvironment. Overall, these findings suggest that down-regulation of FILIP1L is clinically relevant in LUAD, and warrant further efforts to evaluate pharmacologic regimens that either directly or indirectly restore FILIP1L-mediated gene regulation for the treatment of these neoplasms. Significance: This study identifies FILIP1L as a tumor suppressor in LUADs and demonstrates that downregulation of FILIP1L is a clinically relevant event in the pathogenesis and clinical course of these neoplasms.


Assuntos
Adenocarcinoma de Pulmão , Neoplasias Pulmonares , Animais , Camundongos , Humanos , Regulação para Baixo/genética , Mucinas , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Adenocarcinoma de Pulmão/genética , Neoplasias Pulmonares/genética , Inflamação/genética , Fibrose , Fumar , Microambiente Tumoral , Peptídeos e Proteínas de Sinalização Intracelular
4.
Front Oncol ; 11: 718408, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34868914

RESUMO

BACKGROUND: Late-stage diagnosis of ovarian cancer, a disease that originates in the ovaries and spreads to the peritoneal cavity, lowers 5-year survival rate from 90% to 30%. Early screening tools that can: i) detect with high specificity and sensitivity before conventional tools such as transvaginal ultrasound and CA-125, ii) use non-invasive sampling methods and iii) longitudinally significantly increase survival rates in ovarian cancer are needed. Studies that employ blood-based screening tools using circulating tumor-cells, -DNA, and most recently tumor-derived small extracellular vesicles (sEVs) have shown promise in non-invasive detection of cancer before standard of care. Our findings in this study show the promise of a sEV-derived signature as a non-invasive longitudinal screening tool in ovarian cancer. METHODS: Human serum samples as well as plasma and ascites from a mouse model of ovarian cancer were collected at various disease stages. Small extracellular vesicles (sEVs) were extracted using a commercially available kit. RNA was isolated from lysed sEVs, and quantitative RT-PCR was performed to identify specific metastatic gene expression. CONCLUSION: This paper highlights the potential of sEVs in monitoring ovarian cancer progression and metastatic development. We identified a 7-gene panel in sEVs derived from plasma, serum, and ascites that overlapped with an established metastatic ovarian carcinoma signature. We found the 7-gene panel to be differentially expressed with tumor development and metastatic spread in a mouse model of ovarian cancer. The most notable finding was a significant change in the ascites-derived sEV gene signature that overlapped with that of the plasma-derived sEV signature at varying stages of disease progression. While there were quantifiable changes in genes from the 7-gene panel in serum-derived sEVs from ovarian cancer patients, we were unable to establish a definitive signature due to low sample number. Taken together our findings show that differential expression of metastatic genes derived from circulating sEVs present a minimally invasive screening tool for ovarian cancer detection and longitudinal monitoring of molecular changes associated with progression and metastatic spread.

5.
Cancer Res ; 81(21): 5523-5539, 2021 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-34417201

RESUMO

Aneuploid mucinous colorectal adenocarcinoma (MAC) is an aggressive subtype of colorectal cancer with poor prognosis. The tumorigenic mechanisms in aneuploid MAC are currently unknown. Here we show that downregulation of Filamin A-interacting protein 1-like (FILIP1L) is a driver of MAC. Loss of FILIP1L increased xenograft growth, and, in colon-specific knockout mice, induced colonic epithelial hyperplasia and mucin secretion. The molecular chaperone prefoldin 1 (PFDN1) was identified as a novel binding partner of FILIP1L at the centrosomes throughout mitosis. FILIP1L was required for proper centrosomal localization of PFDN1 and regulated proteasome-dependent degradation of PFDN1. Importantly, increased PFDN1, caused by downregulation of FILIP1L, drove multinucleation and cytokinesis defects in vitro and in vivo, which were confirmed by time-lapse imaging and 3D cultures of normal epithelial cells. Overall, these findings suggest that downregulation of FILIP1L and subsequent upregulation of PFDN1 is a driver of the unique neoplastic characteristics in aggressive aneuploid MAC. SIGNIFICANCE: This study identifies FILIP1L as a tumor suppressor in mucinous colon cancer and demonstrates that FILIP1L loss results in aberrant stabilization of a centrosome-associated chaperone protein to drive aneuploidy and disease progression.


Assuntos
Adenocarcinoma Mucinoso/patologia , Biomarcadores Tumorais/metabolismo , Neoplasias Colorretais/patologia , Citocinese , Regulação Neoplásica da Expressão Gênica , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Chaperonas Moleculares/metabolismo , Adenocarcinoma Mucinoso/genética , Adenocarcinoma Mucinoso/metabolismo , Animais , Apoptose , Biomarcadores Tumorais/genética , Proliferação de Células , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Feminino , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Nus , Chaperonas Moleculares/genética , Prognóstico , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
6.
J Pers Med ; 11(7)2021 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-34357103

RESUMO

Nuclear receptor-binding SET domain protein (NSD), a histone methyltransferase, is known to play an important role in cancer pathogenesis. The WHSC1L1 (Wolf-Hirschhorn syndrome candidate 1-like 1) gene, encoding NSD3, is highly expressed in breast cancer, but its role in the development of breast cancer is still unknown. The purpose of this study was to analyze the survival rates and immune responses of breast cancer patients with high WHSC1L1 expression and to validate the results using gradient boosting machine (GBM) in breast cancer. We investigated the clinicopathologic parameters, proportions of immune cells, pathway networks and in vitro drug responses according to WHSC1L1 expression in 456, 1500 and 776 breast cancer patients from the Hanyang University Guri Hospital, METABRIC and TCGA, respectively. High WHSC1L1 expression was associated with poor prognosis, decreased CD8+ T cells and high CD274 expression (encoding PD-L1). In the pathway networks, WHSC1L1 was indirectly linked to the regulation of the lymphocyte apoptotic process. The GBM model with WHSC1L1 showed improved prognostic performance compared with the model without WHSC1L1. We found that VX-11e, CZC24832, LY2109761, oxaliplatin and erlotinib were effective in inhibiting breast cancer cell lines with high WHSC1L1 expression. High WHSC1L1 expression could play potential roles in the progression of breast cancer and targeting WHSC1L1 could be a potential strategy for the treatment of breast cancer.

7.
Exp Mol Med ; 52(11): 1777-1786, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33230251

RESUMO

Micronuclei are small DNA-containing nuclear structures that are spatially isolated from the main nucleus. They are frequently found in pathologies, including cancer. It was recently shown that these nuclear structures are not only biomarkers of disease but also play an active role in tumor biology. Many consequences of micronucleus formation on tumor biology are dependent on the frequent and irreversible rupture of their nuclear envelopes, which results in the exposure of their DNA contents to the cytoplasm. In this review, we discuss models of defective nuclear envelope deposition on missegregated chromosomes that lead to nuclear envelope rupture. Furthermore, we expound upon the various downstream consequences of micronucleus nuclear envelope rupture on cells. These consequences include a massive DNA rearrangement phenomenon called chromothripsis and activation of the cGAS-STING innate immune signaling pathway, which can be a double-edged sword with tumorigenesis and tumor prevention functions. Although micronuclei are small structures, the impact they have on cells and their microenvironment is quite large.


Assuntos
Núcleo Celular , Micronúcleos com Defeito Cromossômico , Membrana Nuclear/metabolismo , Animais , Núcleo Celular/genética , Núcleo Celular/metabolismo , Cromotripsia , Citoplasma/metabolismo , Dano ao DNA , Instabilidade Genômica , Humanos , Imunidade Inata , Mitose , Transdução de Sinais
8.
Nat Commun ; 11(1): 2350, 2020 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-32393766

RESUMO

BET inhibitors are promising therapeutic agents for the treatment of triple-negative breast cancer (TNBC), but the rapid emergence of resistance necessitates investigation of combination therapies and their effects on tumor evolution. Here, we show that palbociclib, a CDK4/6 inhibitor, and paclitaxel, a microtubule inhibitor, synergize with the BET inhibitor JQ1 in TNBC lines. High-complexity DNA barcoding and mathematical modeling indicate a high rate of de novo acquired resistance to these drugs relative to pre-existing resistance. We demonstrate that the combination of JQ1 and palbociclib induces cell division errors, which can increase the chance of developing aneuploidy. Characterizing acquired resistance to combination treatment at a single cell level shows heterogeneous mechanisms including activation of G1-S and senescence pathways. Our results establish a rationale for further investigation of combined BET and CDK4/6 inhibition in TNBC and suggest novel mechanisms of action for these drugs and new vulnerabilities in cells after emergence of resistance.


Assuntos
Quinase 4 Dependente de Ciclina/antagonistas & inibidores , Quinase 6 Dependente de Ciclina/antagonistas & inibidores , Resistencia a Medicamentos Antineoplásicos , Proteínas/antagonistas & inibidores , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Animais , Azepinas/farmacologia , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Clonais , Quinase 4 Dependente de Ciclina/metabolismo , Quinase 6 Dependente de Ciclina/metabolismo , DNA de Neoplasias/metabolismo , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Sinergismo Farmacológico , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Camundongos , Modelos Biológicos , Mutação/genética , Paclitaxel/farmacologia , Piperazinas/farmacologia , Ploidias , Proteínas/metabolismo , Piridinas/farmacologia , Proteína do Retinoblastoma/genética , Proteína do Retinoblastoma/metabolismo , Resultado do Tratamento , Triazóis/farmacologia , Neoplasias de Mama Triplo Negativas/genética , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/genética
9.
ACS Biomater Sci Eng ; 4(7): 2305-2363, 2018 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-30417087

RESUMO

Gene therapy is emerging as the next generation of therapeutic modality with United States Food and Drug Administration approved gene-engineered therapy for cancer and a rare eye-related disorder, but the challenge of real-time monitoring of on-target therapy response remains. In this study, we have designed a theranostic nanoparticle composed of shortwave-infrared-emitting rare-earth-doped nanoparticles (RENPs) capable of delivering genetic cargo and of real-time response monitoring. We showed that the cationic coating of RENPs with branched polyethylenimine (PEI) does not have a significant impact on cellular toxicity, which can be further reduced by selectively modifying the surface characteristics of the PEI coating using counter-ions and expanding their potential applications in photothermal therapy. We showed the tolerability and clearance of a bolus dose of RENPs@PEI in mice up to 7 days after particle injection in addition to the RENPs@PEI ability to distinctively discern lung tumor lesions in a breast cancer mouse model with an excellent signal-to-noise ratio. We also showed the availability of amine functional groups in the collapsed PEI chain conformation on RENPs, which facilitates the loading of genetic cargo that hybridizes with target gene in an in vitro cancer model. The real-time monitoring and delivery of gene therapy at on-target sites will enable the success of an increased number of gene- and cell-therapy products in clinical trials.

10.
Cell Rep ; 25(5): 1255-1267.e5, 2018 10 30.
Artigo em Inglês | MEDLINE | ID: mdl-30380416

RESUMO

Perturbed epigenomic programs play key roles in tumorigenesis, and chromatin modulators are candidate therapeutic targets in various human cancer types. To define singular and shared dependencies on DNA and histone modifiers and transcription factors in poorly differentiated adult and pediatric cancers, we conducted a targeted shRNA screen across 59 cell lines of 6 cancer types. Here, we describe the TRPS1 transcription factor as a strong breast cancer-specific hit, owing largely to lineage-restricted expression. Knockdown of TRPS1 resulted in perturbed mitosis, apoptosis, and reduced tumor growth. Integrated analysis of TRPS1 transcriptional targets, chromatin binding, and protein interactions revealed that TRPS1 is associated with the NuRD repressor complex. These findings uncover a transcriptional network that is essential for breast cancer cell survival and propagation.


Assuntos
Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Linhagem da Célula , Proteínas de Ligação a DNA/metabolismo , Fatores de Transcrição/metabolismo , Transcrição Gênica , Linhagem Celular Tumoral , Sobrevivência Celular/genética , Feminino , Células HEK293 , Humanos , Complexo Mi-2 de Remodelação de Nucleossomo e Desacetilase/metabolismo , Ligação Proteica , RNA Interferente Pequeno/metabolismo , Proteínas Repressoras/metabolismo , Neoplasias de Mama Triplo Negativas/metabolismo , Neoplasias de Mama Triplo Negativas/patologia
11.
Nature ; 561(7724): 551-555, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30232450

RESUMO

Defects in the architecture or integrity of the nuclear envelope are associated with a variety of human diseases1. Micronuclei, one common nuclear aberration, are an origin for chromothripsis2, a catastrophic mutational process that is commonly observed in cancer3-5. Chromothripsis occurs after micronuclei spontaneously lose nuclear envelope integrity, which generates chromosome fragmentation6. Disruption of the nuclear envelope exposes DNA to the cytoplasm and initiates innate immune proinflammatory signalling7. Despite its importance, the basis of the fragility of the micronucleus nuclear envelope  is not known. Here we show that micronuclei undergo defective nuclear envelope assembly. Only 'core' nuclear envelope proteins8,9 assemble efficiently on lagging chromosomes, whereas 'non-core' nuclear envelope proteins8,9, including nuclear pore complexes (NPCs), do not. Consequently, micronuclei fail to properly import key proteins that are necessary for the integrity of the nuclear envelope and genome. We show that spindle microtubules block assembly of NPCs and other non-core nuclear envelope proteins on lagging chromosomes, causing an irreversible defect in nuclear envelope assembly. Accordingly, experimental manipulations that position missegregated chromosomes away from the spindle correct defective nuclear envelope assembly, prevent spontaneous nuclear envelope disruption, and suppress DNA damage in micronuclei. Thus, during mitotic exit in metazoan cells, chromosome segregation and nuclear envelope assembly are only loosely coordinated by the timing of mitotic spindle disassembly. The absence of precise checkpoint controls may explain why errors during mitotic exit are frequent and often trigger catastrophic genome rearrangements4,5.


Assuntos
Cromotripsia , Micronúcleos com Defeito Cromossômico , Mitose , Membrana Nuclear/metabolismo , Pontos de Checagem do Ciclo Celular , Linhagem Celular Tumoral , Segregação de Cromossomos , Cromossomos Humanos/metabolismo , DNA/metabolismo , Dano ao DNA , Instabilidade Genômica , Humanos , Microtúbulos/metabolismo , Poro Nuclear/metabolismo , Fuso Acromático/metabolismo
12.
Oncotarget ; 7(47): 77052-77070, 2016 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-27776341

RESUMO

Filamin A interacting protein 1-like (FILIP1L) is an inhibitor of the canonical WNT pathway. WNT/ß-catenin signaling and its downstream pathway, epithelial-to-mesenchymal transition (EMT), play a key role in ovarian cancer metastasis and chemoresistance. To study the clinical implications of FILIP1L in regulating the WNT/ß-catenin pathway, the expression of FILIP1L, ß-catenin, SNAIL and SLUG was analyzed by immunohistochemistry on tissue microarrays of 369 ovarian samples ranging from normal to metastatic. In addition, the results were validated in mouse model and in vitro cell culture. In the present study, we demonstrated that FILIP1L expression was inversely correlated with poor prognosis, stage and chemoresistance in ovarian cancer. Notably, low FILIP1L expression was independent negative prognostic factor with respect to overall and disease-free survival. FILIP1L inhibited peritoneal metastases in orthotopic mouse model. FILIP1L knockdown induced chemoresistance in ovarian cancer cells and this phenotype was rescued by simultaneous knockdown of FILIP1L and SLUG, an EMT activator. We also demonstrated that FILIP1L regulates ß-catenin degradation. FILIP1L co-localizes with phospho-ß-catenin and increases phospho-ß-catenin at the centrosomes, destined for proteosomal degradation. Finally, we showed that FILIP1L regulates EMT. Overall, these findings suggest that FILIP1L promotes ß-catenin degradation and suppresses EMT, thereby inhibiting metastases and chemoresistance. Our study provides the first clinical relevance of FILIP1L in human cancer, and suggests that FILIP1L may be a novel prognostic marker for chemotherapy in ovarian cancer patients. Further, the modulation of FILIP1L expression may have the potential to be a target for cancer therapy.


Assuntos
Resistencia a Medicamentos Antineoplásicos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Neoplasias Ovarianas/patologia , beta Catenina/metabolismo , Animais , Linhagem Celular Tumoral , Progressão da Doença , Intervalo Livre de Doença , Transição Epitelial-Mesenquimal , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos , Transplante de Neoplasias , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/metabolismo , Fosforilação , Prognóstico , Fatores de Transcrição da Família Snail/metabolismo , Via de Sinalização Wnt
13.
Methods Mol Biol ; 1413: 367-92, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27193861

RESUMO

The link between centrosome amplification and cancer has been recognized for more than a century, raising many key questions about the biology of both normal and cancer cells. In particular, the presence of extra centrosomes imposes a great challenge to a dividing cell by increasing the likelihood of catastrophic multipolar divisions. Only recently have we begun to understand how cancer cells successfully divide by clustering their extra centrosomes for bipolar division. Several hurdles to dissecting centrosome clustering include limitations in the methodologies used to quantify centrosome amplification, and the lack of appropriate cell culture models. Here, we describe how to accurately assess centrosome number and create isogenic cell lines with or without centrosome amplification. We then describe how imaging of cell division in these cell culture models leads to identification of the molecular machinery uniquely required for cells with extra centrosomes. These approaches have led to the identification of molecular targets for selective cancer therapeutics that can kill cancer cells with extra centrosomes without affecting normal cells with two centrosomes. We further anticipate that the approaches described here will be broadly applicable for studying the causes and consequences of centrosome amplification in a variety of contexts across cancer pathophysiology, such as cell migration and metastasis.


Assuntos
Centrossomo/metabolismo , Amplificação de Genes , Mitose , Neoplasias/genética , Neoplasias/metabolismo , Animais , Ciclo Celular/genética , Linhagem Celular Tumoral , Sobrevivência Celular/genética , Citocinese/genética , Expressão Gênica , Humanos , Camundongos , Microscopia de Fluorescência , Microtúbulos/metabolismo , Mitose/genética , Neoplasias/patologia , Fenótipo , Proteínas Serina-Treonina Quinases/genética , Fuso Acromático/metabolismo , Tetraploidia
14.
Annu Rev Pathol ; 11: 283-312, 2016 05 23.
Artigo em Inglês | MEDLINE | ID: mdl-26907526

RESUMO

During tumor evolution, cancer cells can accumulate numerous genetic alterations, ranging from single nucleotide mutations to whole-chromosomal changes. Although a great deal of progress has been made in the past decades in characterizing genomic alterations, recent cancer genome sequencing studies have provided a wealth of information on the detailed molecular profiles of such alterations in various types of cancers. Here, we review our current understanding of the mechanisms and consequences of cancer genome instability, focusing on the findings uncovered through analysis of exome and whole-genome sequencing data. These analyses have shown that most cancers have evidence of genome instability, and the degree of instability is variable within and between cancer types. Importantly, we describe some recent evidence supporting the idea that chromosomal instability could be a major driving force in tumorigenesis and cancer evolution, actively shaping the genomes of cancer cells to maximize their survival advantage.


Assuntos
Transformação Celular Neoplásica/genética , Instabilidade Genômica/genética , Genômica , Neoplasias/genética , Genômica/métodos , Humanos
15.
Dev Cell ; 34(3): 323-37, 2015 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-26235048

RESUMO

Positioning of centrosomes is vital for cell division and development. In metazoan cells, spindle positioning is controlled by a dynamic pool of subcortical actin that organizes in response to the position of retraction fibers. These actin "clouds" are proposed to generate pulling forces on centrosomes and mediate spindle orientation. However, the motors that pull astral microtubules toward these actin structures are not known. Here, we report that the unconventional myosin, Myo10, couples actin-dependent forces from retraction fibers and subcortical actin clouds to centrosomes. Myo10-mediated centrosome positioning requires its direct microtubule binding. Computational image analysis of large microtubule populations reveals a direct effect of Myo10 on microtubule dynamics and microtubule-cortex interactions. Myo10's role in centrosome positioning is distinct from, but overlaps with, that of dynein. Thus, Myo10 plays a key role in integrating the actin and microtubule cytoskeletons to position centrosomes and mitotic spindles.


Assuntos
Divisão Celular/fisiologia , Centrossomo/metabolismo , Dineínas/metabolismo , Miosinas/metabolismo , Fuso Acromático/fisiologia , Citoesqueleto de Actina/metabolismo , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Linhagem Celular Tumoral , Células HeLa , Humanos , Microtúbulos/metabolismo , Miosinas/genética , Interferência de RNA , RNA Interferente Pequeno , Tiazolidinas/farmacologia
16.
J Biol Chem ; 290(27): 16943-53, 2015 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-25979339

RESUMO

Syndecans, a family of transmembrane heparansulfate proteoglycans, are known to interact through their transmembrane domains to form non-covalently linked homodimers, a process essential for their individual functions. Because all syndecan transmembrane domains are highly conserved and thus might mediate interactions between different members of the syndecan family, we investigated syndecan interactions in detail. All recombinant syndecan-2 and -4 protein variants containing the transmembrane domain formed not only sodium dodecyl sulfate (SDS)-resistant homodimers but also SDS-resistant heterodimers. Biochemical and structural data revealed that recombinant syndecan-2 and -4 formed intermolecular interactions in vitro, and the GXXXG motif in transmembrane domain mediated this interaction. When exogenously expressed in rat embryonic fibroblasts, syndecan-2 interacted with syndecan-4 and vice versa. Furthermore, bimolecular fluorescence complementation-based assay demonstrated specific hetero-molecular interactions between syndecan-2 and -4, supporting hetero-oligomer formation of syndecans in vivo. Interestingly, hetero-oligomerization significantly reduced syndecan-4-mediated cellular processes such as protein kinase Cα activation and protein kinase Cα-mediated cell adhesion as well as syndecan-2-mediated tumorigenic activities in colon cancer cells such as migration and anchorage-independent growth. Taken together, these data provide evidence that hetero-oligomerization produces distinct syndecan functions and offer insights into the underlying signaling mechanisms of syndecans.


Assuntos
Sindecana-2/química , Sindecana-2/metabolismo , Sindecana-4/química , Sindecana-4/metabolismo , Motivos de Aminoácidos , Animais , Dimerização , Fibroblastos/química , Fibroblastos/metabolismo , Ligação Proteica , Ratos , Sindecana-2/genética , Sindecana-4/genética
17.
World J Gastroenterol ; 20(47): 18044-7, 2014 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-25548505

RESUMO

Fundic gland polyps (FGPs) are currently the most common type of gastric polyps and are usually benign. However, although rare, gastric adenocarcinoma of FGP has been recently proposed as a new variant of gastric adenocarcinoma. Here we report the first case of a 49-year-old woman with focal signet ring cell carcinoma that arose from an FGP of the stomach. The tumor was completely excised by endoscopic snare polypectomy. FGPs should therefore be evaluated for malignant changes although they occur rarely, if the FGP has an erosive or irregular surface.


Assuntos
Carcinoma de Células em Anel de Sinete/patologia , Fundo Gástrico/patologia , Pólipos/patologia , Gastropatias/patologia , Neoplasias Gástricas/patologia , Biomarcadores Tumorais/análise , Biópsia , Carcinoma de Células em Anel de Sinete/química , Carcinoma de Células em Anel de Sinete/cirurgia , Feminino , Gastrectomia/métodos , Fundo Gástrico/química , Fundo Gástrico/cirurgia , Gastroscopia/métodos , Humanos , Imuno-Histoquímica , Pessoa de Meia-Idade , Pólipos/química , Pólipos/cirurgia , Gastropatias/metabolismo , Gastropatias/cirurgia , Neoplasias Gástricas/química , Neoplasias Gástricas/cirurgia
18.
Expert Opin Ther Targets ; 18(12): 1435-47, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25200207

RESUMO

INTRODUCTION: Filamin A interacting protein 1-like (FILIP1L) is a novel tumor suppressor-like protein that has its expression downregulated in various cancers through promoter hypermethylation. When overexpressed, FILIP1L inhibits cancer cell invasion and metastasis through the inhibition of canonical WNT signaling. AREAS COVERED: This review gives an overview of the structure and isoforms, gene expression and cellular location of FILIP1L, and how FILIP1L inhibits cancer invasion and metastasis. Furthermore, the review discusses the potential mechanism by which FILIP1L inhibits cancer metastasis through inhibiting canonical WNT signaling and thus blocking downstream ß-catenin transcriptional targets. EXPERT OPINION: By inhibiting ß-catenin, the key transcriptional factor of the canonical WNT signaling pathway, FILIP1L could block various downstream pathways that are regulated by ß-catenin transcriptional targets. FILIP1L could therefore have great potential as a novel cancer therapeutic target. However, in order to fulfill its therapeutic potential, its precise mechanism of action of antimetastatic activity has to be identified. In addition, the physiological role of FILIP1L and its relationship with other isoforms needs to be characterized.


Assuntos
Antineoplásicos/administração & dosagem , Sistemas de Liberação de Medicamentos/métodos , Peptídeos e Proteínas de Sinalização Intracelular/biossíntese , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Animais , Sistemas de Liberação de Medicamentos/tendências , Regulação Neoplásica da Expressão Gênica , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/agonistas
19.
Mol Cell ; 54(3): 512-25, 2014 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-24703952

RESUMO

Excluding 53BP1 from chromatin is required to attenuate the DNA damage response during mitosis, yet the functional relevance and regulation of this exclusion are unclear. Here we show that 53BP1 is phosphorylated during mitosis on two residues, T1609 and S1618, located in its well-conserved ubiquitination-dependent recruitment (UDR) motif. Phosphorylating these sites blocks the interaction of the UDR motif with mononuclesomes containing ubiquitinated histone H2A and impedes binding of 53BP1 to mitotic chromatin. Ectopic recruitment of 53BP1-T1609A/S1618A to mitotic DNA lesions was associated with significant mitotic defects that could be reversed by inhibiting nonhomologous end-joining. We also reveal that protein phosphatase complex PP4C/R3ß dephosphorylates T1609 and S1618 to allow the recruitment of 53BP1 to chromatin in G1 phase. Our results identify key sites of 53BP1 phosphorylation during mitosis, identify the counteracting phosphatase complex that restores the potential for DDR during interphase, and establish the physiological importance of this regulation.


Assuntos
Quebras de DNA de Cadeia Dupla , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Processamento de Proteína Pós-Traducional , Sequência de Aminoácidos , Fase G1 , Células HeLa , Humanos , Mitose , Dados de Sequência Molecular , Fosfoproteínas Fosfatases/metabolismo , Fosforilação , Ligação Proteica , Transporte Proteico , Proteína 1 de Ligação à Proteína Supressora de Tumor p53
20.
Biochem Biophys Res Commun ; 446(2): 487-92, 2014 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-24613844

RESUMO

The cell surface heparan sulfate proteoglycan, syndecan-2, is known to play an important role in the tumorigenic activity of colon cancer cells. In addition, the extracellular domain of syndecan-2 is cleaved by matrix metalloproteinase-7 (MMP-7) in various colon cancer cells, but factors involved in regulating this process remain unknown. Here, we demonstrate a role for interleukin-1α (IL-1α) in syndecan-2 shedding in colon cancer cells. Treatment of low metastatic (HT-29) and highly metastatic (HCT-116) colon cancer cells with various soluble growth factors and cytokines revealed that IL-1α specifically increased extracellular shedding of syndecan-2 in a concentration- and time-dependent manner. IL-1α did not affect the expression of syndecan-2, but did significantly reduce its cell surface levels. Notably, IL-1α increased the mRNA expression and subsequent secreted levels of MMP-7 protein and enhanced the phosphorylation of p38 and ERK mitogen-activated protein kinases. Furthermore, increased syndecan-2 shedding was dependent on the mitogen-activated protein kinase-mediated MMP-7 expression. Taken together, these data suggest that IL-1α regulates extracellular domain shedding of syndecan-2 through regulation of the MAP kinase-mediated MMP-7 expression in colon cancer cells.


Assuntos
Neoplasias do Colo/metabolismo , Interleucina-1alfa/metabolismo , Metaloproteinase 7 da Matriz/metabolismo , Sindecana-2/metabolismo , Células HCT116 , Células HT29 , Humanos , Regulação para Cima
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