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1.
Mol Cancer ; 22(1): 206, 2023 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-38093346

RESUMO

BACKGROUND: Social behaviors such as altruism, where one self-sacrifices for collective benefits, critically influence an organism's survival and responses to the environment. Such behaviors are widely exemplified in nature but have been underexplored in cancer cells which are conventionally seen as selfish competitive players. This multidisciplinary study explores altruism and its mechanism in breast cancer cells and its contribution to chemoresistance. METHODS: MicroRNA profiling was performed on circulating tumor cells collected from the blood of treated breast cancer patients. Cancer cell lines ectopically expressing candidate miRNA were used in co-culture experiments and treated with docetaxel. Ecological parameters like relative survival and relative fitness were assessed using flow cytometry. Functional studies and characterization performed in vitro and in vivo include proliferation, iTRAQ-mass spectrometry, RNA sequencing, inhibition by small molecules and antibodies, siRNA knockdown, CRISPR/dCas9 inhibition and fluorescence imaging of promoter reporter-expressing cells. Mathematical modeling based on evolutionary game theory was performed to simulate spatial organization of cancer cells. RESULTS: Opposing cancer processes underlie altruism: an oncogenic process involving secretion of IGFBP2 and CCL28 by the altruists to induce survival benefits in neighboring cells under taxane exposure, and a self-sacrificial tumor suppressive process impeding proliferation of altruists via cell cycle arrest. Both processes are regulated concurrently in the altruists by miR-125b, via differential NF-κB signaling specifically through IKKß. Altruistic cells persist in the tumor despite their self-sacrifice, as they can regenerate epigenetically from non-altruists via a KLF2/PCAF-mediated mechanism. The altruists maintain a sparse spatial organization by inhibiting surrounding cells from adopting the altruistic fate via a lateral inhibition mechanism involving a GAB1-PI3K-AKT-miR-125b signaling circuit. CONCLUSIONS: Our data reveal molecular mechanisms underlying manifestation, persistence and spatial spread of cancer cell altruism. A minor population behave altruistically at a cost to itself producing a collective benefit for the tumor, suggesting tumors to be dynamic social systems governed by the same rules of cooperation in social organisms. Understanding cancer cell altruism may lead to more holistic models of tumor evolution and drug response, as well as therapeutic paradigms that account for social interactions. Cancer cells constitute tractable experimental models for fields beyond oncology, like evolutionary ecology and game theory.


Assuntos
Neoplasias da Mama , MicroRNAs , Humanos , Feminino , Altruísmo , Fosfatidilinositol 3-Quinases , MicroRNAs/genética , Neoplasias da Mama/genética
2.
Mod Pathol ; 34(7): 1320-1332, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33727697

RESUMO

Breast fibroepithelial lesions are biphasic tumors which comprise the common benign fibroadenomas (FAs) and the rarer phyllodes tumors (PTs). This study analyzed 262 (42%) conventional FAs, 45 (7%) cellular FAs, and 321 (51%) benign PTs contributed by the International Fibroepithelial Consortium, using a previously curated 16 gene panel. Benign PTs were found to possess a higher number of mutations, and higher rates of cancer driver gene alterations than both groups of FAs, in particular MED12, TERT promoter, RARA, FLNA, SETD2, RB1, and EGFR. Cases with MED12 mutations were also more likely to have TERT promoter, RARA, SETD2, and EGFR. There were no significant differences detected between conventional FAs and cellular FAs, except for PIK3CA and MAP3K1. TERT promoter alterations were most optimal in discriminating between FAs and benign PTs. Our study affirms the role of sequencing and key mutations that may assist in refining diagnoses of these lesions.


Assuntos
Neoplasias da Mama/genética , Fibroadenoma/genética , Tumor Filoide/genética , Adulto , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/patologia , Análise Mutacional de DNA , Diagnóstico Diferencial , Feminino , Fibroadenoma/diagnóstico , Fibroadenoma/patologia , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Mutação , Tumor Filoide/diagnóstico , Tumor Filoide/patologia
3.
Exp Cell Res ; 350(2): 380-389, 2017 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-28017727

RESUMO

Heparan sulfate 6-O-sulfation is biologically edited by 6-O-sulfotransferases (HS6STs) within heparan sulfate chains. Three isoforms of HS6ST have been identified. These enzymes are found to be differentially expressed in a variety of tissues. Recently, several studies have shown that dysregulation of 6-O-sulfotransferases could be involved in tumorigenesis of several cancers. This study aimed to analyze the expression and function of HS6ST3 in breast cancer. HS6ST3 was found up-regulated in T47D, MCF7 and MDA-MB231 breast cancer cell lines. HS6ST3 was then silenced in T47D and MCF7 using siRNA. Silencing HS6ST3 diminished tumor cell growth, migration and invasion, but enhanced cell adhesion and apoptosis in breast cancer. Gene microarray analysis revealed that silencing HS6ST3 significantly changed the expression of IGF1R and XAF1 in breast cancer cells. Further functional studies showed that the cellular processes were mediated by IGF1R and XAF1 after silencing HS6ST3 in breast cancer cells. Together these results indicate that HS6ST3 might be involved in the tumorigenesis of breast cancer and it could be a promising target in breast cancer therapy.


Assuntos
Neoplasias da Mama/metabolismo , Movimento Celular , Peptídeos e Proteínas de Sinalização Intracelular/genética , Proteínas de Neoplasias/genética , Receptores de Somatomedina/genética , Sulfotransferases/genética , Proteínas Adaptadoras de Transdução de Sinal , Apoptose , Proteínas Reguladoras de Apoptose , Neoplasias da Mama/genética , Adesão Celular , Inativação Gênica , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Células MCF-7 , Proteínas de Neoplasias/metabolismo , Receptor IGF Tipo 1 , Receptores de Somatomedina/metabolismo , Sulfotransferases/metabolismo
4.
Histopathology ; 66(4): 491-9, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25270600

RESUMO

AIMS: Y-box binding protein-1 (YB-1) is known to modulate gene transcription and protein translation, as well as cellular response to drug treatment. The aim of this study is to correlate YB-1 protein expression levels with clinicopathological parameters in intestinal-type gastric cancer tissue samples (as categorized by the Lauren classification) and substantiate the findings with in vitro experimentation. METHODS AND RESULTS: Paraffin-embedded samples from 167 patients with intestinal-type gastric cancer were used for the construction of tissue microarrays (TMAs). TMA slides were immunostained and YB-1 immunoreactivity score was based on the weighted average intensity score. Univariate analysis revealed that YB-1 immunohistochemical expression was correlated significantly with lymph node status (P = 0.054, borderline significance) and perforation (P = 0.043). YB-1 expression was also found to be an independent predictor of lymph node spread by multivariate analysis. Furthermore, siRNA-mediated YB-1 gene knockdown in MKN7 gastric cancer cells (which is known to originate from an intestinal-type gastric cancer tissue) inhibited cell migration (P = 0.0002) and invasion in vitro (P = 0.0129) significantly. CONCLUSION: YB-1 expression is associated with lymph node spread in intestinal-type gastric cancer and is a potential prognostic biomarker in this subtype of gastric cancer.


Assuntos
Linfonodos/metabolismo , Metástase Linfática/patologia , Neoplasias Gástricas/metabolismo , Proteína 1 de Ligação a Y-Box/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/metabolismo , Linhagem Celular Tumoral , Feminino , Humanos , Linfonodos/patologia , Masculino , Pessoa de Meia-Idade , Prognóstico , RNA Interferente Pequeno , Neoplasias Gástricas/patologia , Proteína 1 de Ligação a Y-Box/genética , Adulto Jovem
5.
Breast Cancer Res ; 13(2): R35, 2011 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-21457545

RESUMO

INTRODUCTION: Triple negative breast cancer is associated with poorer prognosis and unresponsiveness to endocrine and anti-HER2 directed agents. Despite emerging data supporting the use of polyADP-ribose polymerase (PARP) inhibitors, complete and durable responses are rare and exploration of additional targeted therapies is needed. Epidermal growth factor receptor (EGFR) is expressed in triple negative breast cancer and several clinical trials are testing the role of anti-EGFR directed therapy. However, the rate of EGFR mutations is poorly defined. We, therefore, sought to characterize EGFR mutations in triple negative breast cancers. METHODS: Seventy samples were randomly chosen from a cohort of 653 triple negative breast tumours for EGFR mutation analysis. These samples were immunostained for EGFR protein expression and consisted of negatively stained and positively stained cases. DNA was extracted from paraffin blocks and polymerase chain reaction was performed to amplify exon regions 18 to 21 of the EGFR gene. Direct sequencing of the purified PCR products was performed. RESULTS: EGFR mutations were found in 8 of 70 samples (11.4%). Mutations were predominantly exon 19 deletions (4 of 70 samples, 5.7%), which clustered in the region spanning codons 746 to 759 within the kinase domain of EGFR. Two types of exon 19 deletions were seen: a 15 nucleotide deletion (del E746-A750) (2 of 70 samples) and a 24 nucleotide deletion (del S752 - I759) (2 of 70 samples). Other exon 19 mutations observed were the inversion of the complementary strand (1 of 70 samples). Exon 21 mutations included missense substitution, L858R (1 of 70 samples) and T847I (2 of 70 samples). Mutations observed were independent of EGFR protein expression determined by immunohistochemical staining. CONCLUSIONS: This study is among the first to document the presence and estimate the prevalence of EGFR mutations in triple negative breast cancer. These findings have potential implications for the design of clinical trials involving anti-EGFR directed therapy which currently do not select for patients based on presence of activating EGFR mutations, which may hence be underpowered to detect significant benefit in unselected populations. More complete sampling of EGFR mutation status in triple negative breast cancer is needed to determine the true mutation rate.


Assuntos
Neoplasias da Mama/genética , DNA de Neoplasias/análise , Genes erbB-1 , Adulto , Idoso , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Estudos de Coortes , Análise Mutacional de DNA , DNA de Neoplasias/genética , Receptores ErbB/biossíntese , Feminino , Humanos , Pessoa de Meia-Idade , Terapia de Alvo Molecular , Mutação , Receptor ErbB-2/metabolismo , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/deficiência , Receptores de Progesterona/metabolismo
6.
Cancers (Basel) ; 13(17)2021 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-34503296

RESUMO

Metastasis is the main cause of mortality in breast cancer patients. There is an unmet need to develop therapies that can impede metastatic spread. Precision oncology has shown great promise for the treatment of cancers, as the therapeutic approach is tailored to a specific group of patients who are likely to benefit from the treatment, rather than the traditional approach of "one size fits all". CD82, also known as KAI1, a glycoprotein belonging to the tetraspanin family and an established metastasis suppressor, could potentially be exploited to hinder metastases in breast cancer. This review explores the prospect of targeting CD82 as an innovative therapeutic approach in precision medicine for breast cancer patients, with the goal of preventing cancer progression and metastasis. Such an approach would entail the selection of a subset of breast cancer patients with low levels of CD82, and instituting an appropriate treatment scheme tailored towards restoring the levels of CD82 in this group of patients. Proposed precision treatment regimens include current modalities of treating breast cancer, in combination with either clinically approved drugs that could restore the levels of CD82, CD82 peptide mimics or non-coding RNA-based therapeutics.

7.
Mod Pathol ; 23(12): 1559-66, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20834237

RESUMO

Calreticulin is a chaperone protein located in the lumen of the endoplasmic reticulum. The association of calreticulin with pathological conditions such as autoimmune disorders and certain types of cancer have been reported. However, little is known about its role in the pathogenesis of breast cancer. The aim of this study was to determine the expression of calreticulin in vitro and correlate its expression levels in breast cancer tissue samples with clinicopathological parameters. Calreticulin expression was evaluated in MCF-7 and MDA-MB-231 breast cancer cells by real-time RT-PCR, Western blot, immunohistochemistry, and immunofluorescence staining. Patient tissue microarrays were constructed from 228 breast cancer specimens for immunohistochemical analysis. The in vitro study showed a higher calreticulin expression in more aggressive MDA-MB-231 cells as compared with MCF-7 cells at both mRNA and protein levels. In all, 227 out of 228 breast cancer samples exhibited calreticulin staining in at least 5% of the cancer cells. Calreticulin immunostaining was observed to be localized to the cytoplasm of the cancer cells. Regression analysis of calreticulin immunostaining in the tissue microarrays revealed that its expression was positively correlated to logarithm of (log) tumor size (P=0.046) and development of distant metastasis (P=0.017). Multivariate analysis confirmed calreticulin expression as an independent predictor of log tumor size and occurrence of distant metastasis. The data suggest that calreticulin expression is associated with more advanced tumors and is a potential prognostic biomarker.


Assuntos
Biomarcadores Tumorais/análise , Neoplasias da Mama/metabolismo , Calreticulina/biossíntese , Carcinoma Ductal de Mama/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/metabolismo , Western Blotting , Neoplasias da Mama/patologia , Calreticulina/análise , Carcinoma Ductal de Mama/patologia , Feminino , Imunofluorescência , Humanos , Imuno-Histoquímica , Pessoa de Meia-Idade , Prognóstico , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise Serial de Tecidos , Adulto Jovem
8.
J Pathol ; 217(4): 563-70, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19116991

RESUMO

Metallothionein (MT) plays a role in fundamental cellular processes such as proliferation, apoptosis and differentiation. We examined MT expression in women with invasive breast ductal carcinoma who underwent mastectomy/lumpectomy without neo-adjuvant treatment. We showed that MT was over-expressed in 87.9% of breast cancer tissues examined, with the mean percentage of positive cells at 30%. There were two patterns of MT expression: predominantly cytoplasmic in 75.9% and nuclear in 24.1% of MT-positive cases. Higher MT scores were associated with poorer histological grade (p = 0.009) but were independent of age, tumour size and oestrogen receptor status. For patients who were treated with adjuvant chemotherapy (cyclophosphamide/methotrexate/5 fluorouracil- or doxorubicin-based regimes), those with high MT expression had a significantly lower recurrence-free survival (p = 0.048), suggesting a role of MT in predicting disease recurrence. Down-regulation of MT in MCF-7 cells by silencing the MT-2A gene (the most abundantly expressed of the 10 known functional MT isoforms) increased chemosensitivity of the cells to doxorubicin. To examine the mechanisms underlying these clinical data, we used siRNAs to decrease MT-2A mRNA expression and protein expression. In MT down-regulated cells challenged with the IC(50) concentration of doxorubicin, we observed a significant reduction in cell viability. Cell cycle analysis also revealed a corresponding increase in apoptosis in the MT down-regulated cells following doxorubicin exposure, showing that down-regulation of MT increased susceptibility to doxorubicin cytotoxicity. The data suggest that MT could be a potential marker of chemoresistance and a molecular therapeutic target.


Assuntos
Biomarcadores Tumorais/análise , Neoplasias da Mama/metabolismo , Carcinoma Ductal de Mama/metabolismo , Resistencia a Medicamentos Antineoplásicos , Metalotioneína/análise , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos Hormonais/uso terapêutico , Biomarcadores Tumorais/genética , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/tratamento farmacológico , Carcinoma Ductal de Mama/patologia , Intervalo Livre de Doença , Doxorrubicina/administração & dosagem , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Metalotioneína/genética , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Isoformas de Proteínas/análise , Isoformas de Proteínas/genética , Interferência de RNA , RNA Interferente Pequeno/farmacologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa
9.
Mod Pathol ; 22(2): 282-90, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18978732

RESUMO

The Y-Box-binding protein-1, a member of the cold-shock domain DNA- and RNA-binding protein superfamily, is known to mediate chemoresistance. The aim of this study was to determine the expression of Y-Box-binding protein-1 in nasopharyngeal cancer in vitro and in tumor tissue samples as well as analyze the clinicopathological significance of Y-Box-binding protein-1 expression in nasopharyngeal cancer, in particular as a predictor of outcome after treatment. The Y-Box-binding protein-1 expression profile was evaluated at the mRNA and protein levels in poorly differentiated CNE-2 nasopharyngeal cancer cells by real-time RT-PCR, western blot analysis and immunohistochemistry. Y-Box-binding protein-1 expression in 143 nasopharyngeal cancer specimens was examined by immunohistochemistry and correlated with clinicopathologic parameters. Y-Box-binding protein-1 mRNA and protein were found to be expressed in CNE-2 nasopharyngeal cancer cells in vitro. Of 143 patient tissue sections, 137 (96%) were stained positive for the Y-Box-binding protein-1 protein. Y-Box-binding protein-1 immunostaining was observed to be predominantly cytoplasmic. A higher recurrence of nasopharyngeal cancer was found in patients whose tissues had increased Y-Box-binding protein-1 expression (P<0.001). The Cox proportionate hazard regression model also established that high Y-Box-binding protein-1 immunoreactivity was significantly correlated with increased risk (2.13 times) of recurrence as compared to low Y-Box-binding protein-1 immunoreactivity (P=0.01). Within groups of patients treated by radiotherapy or chemoradiotherapy, recurrent cases had significantly higher Y-Box-binding protein-1 expression than nonrecurrent cases (P<0.001 and P=0.0035, respectively). These data suggest that Y-Box-binding protein-1 expression has clinicopathological significance with potential as a predictive marker of recurrence in nasopharyngeal cancer patients who undergo radiotherapy or chemoradiotherapy.


Assuntos
Biomarcadores Tumorais/análise , Proteínas de Ligação a DNA/análise , Resistencia a Medicamentos Antineoplásicos , Neoplasias Nasofaríngeas/química , Proteínas Nucleares/análise , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/genética , Biópsia , Western Blotting , Linhagem Celular Tumoral , Quimioterapia Adjuvante , Proteínas de Ligação a DNA/genética , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Neoplasias Nasofaríngeas/tratamento farmacológico , Neoplasias Nasofaríngeas/genética , Neoplasias Nasofaríngeas/radioterapia , Proteínas Nucleares/genética , Valor Preditivo dos Testes , Modelos de Riscos Proporcionais , RNA Mensageiro/análise , Radioterapia Adjuvante , Recidiva , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Medição de Risco , Falha de Tratamento , Proteína 1 de Ligação a Y-Box , Adulto Jovem
10.
Mod Pathol ; 21(10): 1183-91, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18536655

RESUMO

Previous studies have suggested that breast cancer in young women has more aggressive biological features and poorer prognosis. However, the role of biological markers in these patients is not well understood. We aimed to learn more about this disease in a cohort of 125 young women from Singapore, Japan and Hong Kong, aged 35 years or less, with invasive breast cancer by evaluating the expression of vimentin and the basal cytokeratins CK14, CK5/6 and 34 beta E12. Both standard paraffin sections and tissue microarrays were used in the immunohistochemical evaluation of expression patterns of these four biological markers. CK5/6, CK14, vimentin and 34 beta E12, in increasing order of proportion, were detected in invasive carcinomas. Basal cytokeratins and vimentin showed significant inverse relationship with estrogen and progesterone receptor status while CK14 expression was found to be directly associated with c-erbB2 status. Basal cytokeratins and vimentin immunoreactivities were directly associated with CD117 and EGFR expression. Vimentin and 34 beta E12 immunopositivity correlated with tumor size, while vimentin was associated with higher histological grade. Our findings are in concert with reports that expression of basal cytokeratins and vimentin is correlated with adverse pathological parameters.


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/metabolismo , Carcinoma Ductal de Mama/metabolismo , Carcinoma Lobular/metabolismo , Queratinas/metabolismo , Vimentina/metabolismo , Adulto , Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/secundário , Carcinoma Lobular/secundário , Linhagem Celular Tumoral , Estudos de Coortes , Feminino , Humanos , Linfonodos/patologia , Metástase Linfática , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Análise Serial de Tecidos
11.
Mod Pathol ; 21(7): 893-901, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18487997

RESUMO

Chondroitin sulfate is a structurally diverse glycosaminoglycan, which contains a variable degree of sulfation that helps to determine its biological function. It is involved in the regulation of cellular activity and has been implicated in carcinogenesis. To determine if the non-sulfated chondroitin backbone has a functional role in prostate cancer, we analyzed its expression by immunohistochemistry using the 1B5 monoclonal antibody and a set of tissue microarrays constructed with 227 prostate specimen cores from 81 cases of benign prostate tissue and 77 cases of prostate cancer, of which 69 of these cases are matched. Non-sulfated chondroitin was found in the secretory epithelial cells and stromal regions of both prostatic adenocarcinoma and benign prostatic tissues, as well as in the basal cells of benign glands. A higher percentage of cancerous cells were stained positively for non-sulfated chondroitin as compared with benign secretory cells of the same patient. Cancerous cells stained more intensely for non-sulfated chondroitin. This increase in percentage of cells stained and increase in staining intensity were associated with higher pathological T stage and extraprostatic extension. Non-sulfated chondroitin expression (either staining intensity or percentage of cells stained) in adenocarcinoma and its peritumoral stroma correlated significantly with several clinicopathological parameters of unfavorable outcome, including higher pathological T stage and Gleason score, presence of tumor in both prostatic lobes, extraprostatic extension, seminal vesicle involvement and preoperative prostate-specific antigen levels. These data suggest that non-sulfated chondroitin is a potentially useful biomarker for prostate cancer, and may be involved in regulating prostate cancer behavior.


Assuntos
Adenocarcinoma/diagnóstico , Biomarcadores Tumorais/metabolismo , Condroitina/metabolismo , Neoplasias da Próstata/diagnóstico , Adenocarcinoma/metabolismo , Idoso , Contagem de Células , Técnica Indireta de Fluorescência para Anticorpo , Humanos , Técnicas Imunoenzimáticas , Masculino , Pessoa de Meia-Idade , Prognóstico , Próstata/metabolismo , Próstata/patologia , Neoplasias da Próstata/metabolismo , Células Estromais/metabolismo , Células Estromais/patologia , Análise Serial de Tecidos
12.
ScientificWorldJournal ; 8: 270-4, 2008 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-18661049

RESUMO

Heat shock proteins (HSPs) are evolutionarily conserved molecules and play important roles in fundamental cellular processes. They serve as molecular chaperones and hence provide a protective function in ensuring cell survival and repair of cellular damage after a stressful stimulus. This paper summarizes the current knowledge about the different roles of HSPs in aging and disease, focusing on the neurodegenerative disorders of Alzheimer's marks disease, Parkinson's disease, Huntington's marks disease, and prion disease.


Assuntos
Proteínas de Choque Térmico/fisiologia , Doenças Neurodegenerativas/fisiopatologia , Envelhecimento/fisiologia , Animais , Humanos
13.
Virchows Arch ; 472(4): 615-621, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29127495

RESUMO

Phyllodes tumours (PTs) of the breast are uncommon fibroepithelial neoplasms comprising 0.3-1.0% of all primary breast tumours. The majority of PTs are benign and generally well managed with surgery. However, malignant PTs, and occasionally borderline PTs, can behave in a clinically aggressive manner by metastasizing to distant organs. Although distant metastasis is rare, the prognosis of patients with metastasis is dismal as many are unresponsive to standard chemotherapy and the risk of death is high. In this study, we correlated clinicopathological parameters to survival outcomes in a cohort of patients diagnosed with malignant PTs in our institution. The study cohort comprised 83 cases of malignant PTs diagnosed at the Department of Anatomical Pathology, Singapore General Hospital from 1994 to 2015. Clinicopathological features and follow-up were obtained from hospital records. Metastasis-free survival (MFS) and overall survival (OS) were estimated with the Kaplan-Meier method and compared between groups using the log-rank test. Cox regression was carried out to identify factors predictive for metastasis. Mean and median age of patients was 48 years (range 21-71 years). Tumour size measured from 30 to 220 mm (mean 90 mm, median 77 mm). Follow-up data was available for 68 patients. Mean and median follow-up was 90 and 57 months, respectively, with a maximum of 291 months. Distant metastasis occurred in 16 out of 68 patients (23.5%). The most common site of metastasis was the lung. Malignant heterologous elements were observed in 16 (19.3%) cases. Individual clinicopathological parameters had no impact on outcome. On Kaplan-Meier analysis, women with large tumours and presence of malignant heterologous elements showed trends for poorer MFS (p = 0.217 and p = 0.566, respectively). However, the combination of large tumours (≥ 90 mm) containing malignant heterologous elements disclosed significantly worse MFS (p = 0.043) and a trend for poorer OS (p = 0.238). On multivariate analysis, large tumours harbouring malignant heterologous elements independently predicted metastasis (95% CI 1.041-12.517, HR 2.434, p = 0.049). Our study demonstrates that tumour size and presence of malignant heterologous elements predicted metastasis in malignant PTs. Further work needs to be done in determining if protein biomarkers and genomic aberrations are able to additionally refine metastatic risk and define therapeutic targets.


Assuntos
Neoplasias da Mama/patologia , Metástase Neoplásica/patologia , Tumor Filoide/patologia , Adulto , Idoso , Neoplasias da Mama/mortalidade , Feminino , Humanos , Estimativa de Kaplan-Meier , Pessoa de Meia-Idade , Tumor Filoide/mortalidade , Modelos de Riscos Proporcionais , Adulto Jovem
14.
Chem Biol Interact ; 289: 81-89, 2018 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-29705079

RESUMO

Gold nanoparticles (AuNPs) have emerging applications in biomedicine and the industry. Exposure to AuNPs has previously been shown to alter the transcriptional activity of nuclear factor kappa B (NF-kB), which is known to mediate physiological and pathological processes. This study seeks to provide mechanistic insights into AuNP-induced NF-kB activation in Small Airway Epithelial Cells (SAECs) in vitro. Increased NF-kB transcriptional activity (quantified by the luciferase reporter assay) was observed in AuNP-treated SAECs. Transcriptomic analysis revealed differential expression of 42 genes, which regulate functional processes that include cellular response to stimulus, chemicals and stress as well as immune response. Notably, the gene expression of serum amyloid A1 (SAA1), an acute phase protein and Toll-like receptor 2 (TLR2) were found to be up-regulated. As TLR2 is known to be a functional receptor of SAA1, a co-immunoprecipitation assay was performed. SAA1 was observed to be co-immunoprecipitated with the TLR2 protein and this protein-protein interaction was further supported by in silico computer based protein modeling. The present study suggests that AuNPs may potentially induce SAA1-TLR2-mediated NF-kB transcription factor activation in lung epithelial cells, highlighting that nano-bio interactions could result in biological effects that may affect cells.


Assuntos
Ouro/química , Pulmão/metabolismo , Nanopartículas Metálicas/química , NF-kappa B/metabolismo , Proteína Amiloide A Sérica/metabolismo , Transdução de Sinais , Receptor 2 Toll-Like/metabolismo , Células Epiteliais/metabolismo , Células Epiteliais/ultraestrutura , Perfilação da Expressão Gênica , Humanos , Nanopartículas Metálicas/ultraestrutura , Modelos Biológicos , Ligação Proteica
15.
Oncol Rep ; 16(6): 1397-402, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17089067

RESUMO

Photoactivation of hypericin is known to generate reactive oxygen species and induce phototoxic effects. However, modulation of the cellular antioxidant defense would influence the extent and severity of the photodynamic effects. We have previously shown that hypericin-mediated photodynamic therapy (PDT) induced a significant reduction of Glutathione S-transferase activity. In this study, we investigated the phototoxic effects of hypericin-mediated PDT in nasopharyngeal cancer (NPC) in vitro and analyzed the expression of metallothionein (MT), a family of potential free radical scavengers. HK1 NPC cells were subjected to PDT treatment in vitro, and the effects on cell death were analyzed by flow cytometry (using propidium iodide and Annexin V staining) and transmission electron microscopy. The expression profile of MT-1E and MT-2A isoforms (the only functional MT isoforms expressed in HK1 NPC cells) were determined by quantitative real-time RT-PCR. The results showed that hypericin PDT induced necrotic cell death as evidenced by the absence of a subdiploid peak and decreased Annexin-V fluorescence. Ultrastructural examination verified the presence of cell necrosis. There was a significant up-regulation of MT-1E and MT-2A isoforms six hours following PDT, with an approximately 50-fold rise in the expression level of MT-1E and a 15-fold increase of MT-2A. Hence, despite the up-regulation of MT, cells still succumbed to PDT-induced necrosis. It appears that the oxidative stress induced by PDT overwhelmed the antioxidant defense mechanism such as the alteration of MT levels in tumor cells.


Assuntos
Metalotioneína/efeitos dos fármacos , Metalotioneína/metabolismo , Neoplasias Nasofaríngeas/metabolismo , Perileno/análogos & derivados , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/farmacologia , Antracenos , Citometria de Fluxo , Humanos , Técnicas In Vitro , Neoplasias Nasofaríngeas/ultraestrutura , Necrose/induzido quimicamente , Perileno/farmacologia , Isoformas de Proteínas/efeitos dos fármacos , Isoformas de Proteínas/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Tumorais Cultivadas , Regulação para Cima
16.
J Clin Pathol ; 69(10): 878-83, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26926102

RESUMO

AIMS: Altered expression of the Claudin (CLDN) superfamily of tight junction proteins has been reported in breast cancer. The aim of this study was to examine the immunohistochemical expression of CLDN 12 and its prognostic significance in breast cancer tissues. METHODS: Immunohistochemical expression of CLDN 12 was performed on tissue microarrays consisting of 232 cases of breast carcinoma and correlated with clinicopathological features as well as survival of the patients with breast cancer. RESULTS: For the estrogen receptor (ER)-negative subgroup of patients with breast cancer, CLDN 12 expression was shown to be an independent predictor of poor overall survival (HR=2.345; p=0.020) and disease-free survival (HR=2.177; p=0.026) but not for the ER-positive tumours. CONCLUSIONS: The findings suggest that CLDN 12 expression could be clinically useful for predicting the survival of the ER-negative subgroup of patients with breast cancer.


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/metabolismo , Claudinas/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/diagnóstico , Intervalo Livre de Doença , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Imuno-Histoquímica , Pessoa de Meia-Idade , Prognóstico , Receptores de Estrogênio/metabolismo , Análise Serial de Tecidos , Adulto Jovem
17.
Brain Res ; 1055(1-2): 137-42, 2005 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-16095570

RESUMO

Oxidative stress plays an important role in the pathogenesis of neurodegeneration after the acute central nervous system injury. We reported previously that increased nitric oxide (NO) production following spinal cord hemisection tends to lead to neurodegeneration in neurons of the nucleus dorsalis (ND) that normally lacks expression of neuronal NO synthase (nNOS) in opposition to those in the red nucleus (RN) that constitutively expresses nNOS. We wondered whether oxidative stress could be a mechanism underlying this NO involved neurodegeneration. In the present study, we examined oxidative damage evaluated by the presence of 4-hydroxynonenal (HNE) and iron accumulation and expression of putative antioxidant enzymes heme oxygenase-1 (HO-1) and superoxide dismutase (SOD) in neurons of the ND and RN after spinal cord hemisection. We found that HNE expression was induced in neurons of the ipsilateral ND from 1 to 14 days following spinal cord hemisection. Concomitantly, iron staining was seen from 7 to 14 days after lesion. HO-1, however, was only transiently induced in ipsilateral ND neurons between 3 and 7 days after lesion. In contrast to the ND neurons, HNE was undetectable and iron level was unaltered in the RN neurons after spinal cord hemisection. HO-1, SOD-Cu/Zn and SOD-Mn were constitutively expressed in RN neurons, and lesion to the spinal cord did not change their expression. These results suggest that oxidative stress is involved in the degeneration of the lesioned ND neurons; whereas constitutive antioxidant enzymes may protect the RN neurons from oxidative damage.


Assuntos
Antioxidantes/uso terapêutico , Núcleo Mediodorsal do Tálamo/patologia , Neurônios/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Núcleo Rubro/patologia , Traumatismos da Medula Espinal , Aldeídos/metabolismo , Animais , Contagem de Células/métodos , Lateralidade Funcional , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/fisiologia , Histocitoquímica/métodos , Imuno-Histoquímica/métodos , Ferro/metabolismo , Masculino , Neurônios/patologia , Neurônios/fisiologia , Estresse Oxidativo/fisiologia , Ratos , Ratos Wistar , Traumatismos da Medula Espinal/tratamento farmacológico , Traumatismos da Medula Espinal/patologia , Traumatismos da Medula Espinal/fisiopatologia , Coloração e Rotulagem/métodos , Superóxido Dismutase/metabolismo , Fatores de Tempo
18.
Exp Biol Med (Maywood) ; 240(7): 846-53, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25573962

RESUMO

Complement component 1, q subcomponent binding protein (C1QBP), is a multi-compartmental protein with higher mRNA expression reported in breast cancer tissues. This study evaluated the association between immunohistochemical expression of the C1QBP protein in breast cancer tissue microarrays (TMAs) and clinicopathological parameters, in particular tumor size. In addition, an in vitro study was conducted to substantiate the breast cancer TMA findings. Breast cancer TMAs were constructed from pathological specimens of patients diagnosed with invasive ductal carcinoma. C1QBP protein and proliferating cell nuclear antigen (PCNA) immunohistochemical analyses were subsequently performed in the TMAs. C1QBP immunostaining was detected in 131 out of 132 samples examined. The C1QBP protein was predominantly localized in the cytoplasm of the breast cancer cells. Univariate analysis revealed that a higher C1QBP protein expression was significantly associated with older patients (P = 0.001) and increased tumor size (P = 0.002). Multivariate analysis showed that C1QBP is an independent predictor of tumor size in progesterone-positive tumors. Furthermore, C1QBP was also significantly correlated with expression of PCNA, a known marker of proliferation. Inhibition of C1QBP expression was performed by transfecting C1QBP siRNA into T47D breast cancer cells, a progesterone receptor-positive breast cancer cell line. C1QBP gene expression was analyzed by real-time RT-PCR, and protein expression by Western blot. Cell proliferation assays were also performed by commercially available assays. Down-regulation of C1QBP expression significantly decreased cell proliferation and growth in T47D cells. Taken together, our findings suggest that the C1QBP protein could be a potential proliferative marker in breast cancer.


Assuntos
Biomarcadores Tumorais/análise , Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/patologia , Proteínas de Transporte/biossíntese , Proteínas Mitocondriais/biossíntese , Adulto , Idoso , Idoso de 80 Anos ou mais , Western Blotting , Neoplasias da Mama/metabolismo , Carcinoma Ductal de Mama/metabolismo , Proteínas de Transporte/análise , Proliferação de Células , Feminino , Humanos , Imuno-Histoquímica , Pessoa de Meia-Idade , Proteínas Mitocondriais/análise , Ligação Proteica , Reação em Cadeia da Polimerase em Tempo Real , Análise Serial de Tecidos , Adulto Jovem
19.
Singapore Med J ; 55(9): 468-72, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25273930

RESUMO

INTRODUCTION: While overexpression of syndecan-1 has been associated with aggressive breast cancer in the Caucasian population, the expression pattern of syndecan-1 in Asian women remains unclear. Triple-positive breast carcinoma, in particular, is a unique subtype that has not been extensively studied. We aimed to evaluate the role of syndecan-1 as a potential biomarker and prognostic factor for triple-positive breast carcinoma in Asian women. METHODS: Using immunohistochemistry, staining scores of 61 triple­positive breast carcinoma specimens were correlated with patients' clinicopathological variables such as age, ethnicity, tumour size, histological grade, lymph node status, lymphovascular invasion, associated ductal carcinoma in situ grade, recurrence and overall survival. RESULTS: Syndecan-1 had intense staining scores in triple­positive invasive ductal breast carcinomas when compared to normal breast tissue. On multivariate analysis, syndecan-1 epithelial total percentage and immunoreactivity score showed statistical correlation with survival (p = 0.02). CONCLUSION: The intense staining scores of syndecan-1 and their correlation with overall survival in patients with triple-positive breast carcinoma suggest that syndecan-1 may have a role as a biological and prognostic marker in patients with this specific subtype of breast cancer.


Assuntos
Biomarcadores Tumorais/sangue , Neoplasias da Mama/sangue , Neoplasias da Mama/mortalidade , Sindecana-1/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Povo Asiático , Neoplasias da Mama/classificação , Receptor alfa de Estrogênio/metabolismo , Feminino , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Pessoa de Meia-Idade , Análise Multivariada , Prognóstico , Receptor ErbB-2/metabolismo , Receptores de Progesterona/metabolismo , Análise Serial de Tecidos , Resultado do Tratamento
20.
J Clin Invest ; 124(9): 3807-24, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25083991

RESUMO

Despite advancement in breast cancer treatment, 30% of patients with early breast cancers experience relapse with distant metastasis. It is a challenge to identify patients at risk for relapse; therefore, the identification of markers and therapeutic targets for metastatic breast cancers is imperative. Here, we identified DP103 as a biomarker and metastasis-driving oncogene in human breast cancers and determined that DP103 elevates matrix metallopeptidase 9 (MMP9) levels, which are associated with metastasis and invasion through activation of NF-κB. In turn, NF-κB signaling positively activated DP103 expression. Furthermore, DP103 enhanced TGF-ß-activated kinase-1 (TAK1) phosphorylation of NF-κB-activating IκB kinase 2 (IKK2), leading to increased NF-κB activity. Reduction of DP103 expression in invasive breast cancer cells reduced phosphorylation of IKK2, abrogated NF-κB-mediated MMP9 expression, and impeded metastasis in a murine xenograft model. In breast cancer patient tissues, elevated levels of DP103 correlated with enhanced MMP9, reduced overall survival, and reduced survival after relapse. Together, these data indicate that a positive DP103/NF-κB feedback loop promotes constitutive NF-κB activation in invasive breast cancers and activation of this pathway is linked to cancer progression and the acquisition of chemotherapy resistance. Furthermore, our results suggest that DP103 has potential as a therapeutic target for breast cancer treatment.


Assuntos
Neoplasias da Mama/patologia , Proteína DEAD-box 20/fisiologia , Neoplasias da Mama/mortalidade , Linhagem Celular Tumoral , Movimento Celular , Proteína DEAD-box 20/análise , Proteína DEAD-box 20/genética , Feminino , Humanos , Quinase I-kappa B/metabolismo , MAP Quinase Quinase Quinases/fisiologia , Metaloproteinase 9 da Matriz/análise , Metaloproteinase 9 da Matriz/genética , NF-kappa B/fisiologia , Invasividade Neoplásica , Metástase Neoplásica
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