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1.
Histopathology ; 85(3): 510-520, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39030792

RESUMO

AIMS: Ductal carcinoma in situ (DCIS) is recognised by the World Health Organisation (WHO) Classification of Tumours (WCT) as a non-invasive neoplastic epithelial proliferation confined to the mammary ducts and lobules. This report categorises the references cited in the DCIS chapter of the 5th edition of the WCT (Breast Tumours) according to prevailing evidence levels for evidence-based medicine and the Hierarchy of Evidence for Tumour Pathology (HETP), identifying potential gaps that can inform subsequent editions of the WCT for this tumour. METHODS AND RESULTS: We included all citations from the DCIS chapter of the WCT (Breast Tumours, 5th edition). Each citation was appraised according to its study design and evidence level. We developed our map of cited evidence, which is a graphical matrix of tumour type (column) and tumour descriptors (rows). Spheres were used to represent the evidence, with size and colour corresponding to their number and evidence level respectively. Thirty-six publications were retrieved. The cited literature in the DCIS chapter comprised mainly case series and were regarded as low-level. We found an unequal distribution of citations among tumour descriptors. 'Pathogenesis' and 'prognosis and prediction' contained the most references, while 'clinical features', 'aetiology' and 'diagnostic molecular pathology' had only a single citation each. 'Prognosis and prediction' had the greatest proportion of moderate- and high-levels of evidence. CONCLUSION: Our findings align with the disposition for observational studies inherent in the field of pathology. Our map is a springboard for future efforts in mapping all available evidence on DCIS, potentially augmenting the editorial process and future editions of WCTs.


Assuntos
Neoplasias da Mama , Carcinoma Intraductal não Infiltrante , Organização Mundial da Saúde , Humanos , Neoplasias da Mama/patologia , Neoplasias da Mama/classificação , Carcinoma Intraductal não Infiltrante/patologia , Carcinoma Intraductal não Infiltrante/classificação , Feminino , Medicina Baseada em Evidências
2.
Molecules ; 29(12)2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38930939

RESUMO

Atherosclerosis continues to be a leading cause of morbidity and mortality globally. The precise evaluation of the extent of an atherosclerotic plaque is essential for forecasting its likelihood of causing health concerns and tracking treatment outcomes. When compared to conventional methods used, nanoparticles offer clear benefits and excellent development opportunities for the detection and characterisation of susceptible atherosclerotic plaques. In this review, we analyse the recent advancements of nanoparticles as theranostics in the management of atherosclerosis, with an emphasis on applications in drug delivery. Furthermore, the main issues that must be resolved in order to advance clinical utility and future developments of NP research are discussed. It is anticipated that medical NPs will develop into complex and advanced next-generation nanobotics that can carry out a variety of functions in the bloodstream.


Assuntos
Aterosclerose , Sistemas de Liberação de Medicamentos , Nanopartículas , Humanos , Aterosclerose/tratamento farmacológico , Nanopartículas/química , Sistemas de Liberação de Medicamentos/métodos , Animais , Nanomedicina Teranóstica/métodos , Placa Aterosclerótica/tratamento farmacológico , Portadores de Fármacos/química
3.
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
4.
Int J Mol Sci ; 24(2)2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36674861

RESUMO

Breast carcinoma is the most prevalent cancer in women globally, with complex genetic and molecular mechanisms that underlie its development and progression. Several challenges such as metastasis and drug resistance limit the prognosis of breast cancer, and hence a constant search for better treatment regimes, including novel molecular therapeutic targets is necessary. Complement component 1, q subcomponent binding protein (C1QBP), a promising molecular target, has been implicated in breast carcinogenesis. In this study, the role of C1QBP in breast cancer progression, in particular cancer cell growth, was determined in triple negative MDA-MB-231 breast cancer cells. Depletion of C1QBP decreased cell proliferation, whereas the opposite effect was observed when C1QBP was overexpressed in MDA-MB-231 cells. Furthermore, gene expression profiling and pathway analysis in C1QBP depleted cells revealed that C1QBP regulates several signaling pathways crucial for cell growth and survival. Taken together, these findings provide a deeper comprehension of the role of C1QBP in triple negative breast cancer, and could possibly pave the way for future advancement of C1QBP-targeted breast cancer therapy.


Assuntos
Neoplasias da Mama , Neoplasias de Mama Triplo Negativas , Feminino , Humanos , Neoplasias da Mama/metabolismo , Proteínas Mitocondriais/metabolismo , Transdução de Sinais , Proteínas de Transporte/metabolismo , Proliferação de Células , Linhagem Celular Tumoral , Neoplasias de Mama Triplo Negativas/genética
5.
Angew Chem Int Ed Engl ; 62(44): e202309610, 2023 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-37675645

RESUMO

Molecular recognition of complex isomeric biomolecules remains challenging in surface-enhanced Raman scattering (SERS) spectroscopy due to their small Raman cross-sections and/or poor surface affinities. To date, the use of molecular probes has achieved excellent molecular sensitivities but still suffers from poor spectral specificity. Here, we induce "charge and geometry complementarity" between probe and analyte as a key strategy to achieve high spectral specificity for effective SERS molecular recognition of structural analogues. We employ 4-mercaptopyridine (MPY) as the probe, and chondroitin sulfate (CS) disaccharides with isomeric sulfation patterns as our proof-of-concept study. Our experimental and in silico studies reveal that "charge and geometry complementarity" between MPY's binding pocket and the CS sulfation patterns drives the formation of site-specific, multidentate interactions at the respective CS isomerism sites, which "locks" each CS in its analogue-specific complex geometry, akin to molecular docking events. Leveraging the resultant spectral fingerprints, we achieve > 97 % classification accuracy for 4 CSs and 5 potential structural interferences, as well as attain multiplex CS quantification with < 3 % prediction error. These insights could enable practical SERS differentiation of biologically important isomers to meet the burgeoning demand for fast-responding applications across various fields such as biodiagnostics, food and environmental surveillance.


Assuntos
Sondas Moleculares , Análise Espectral Raman , Análise Espectral Raman/métodos , Simulação de Acoplamento Molecular
6.
Breast Cancer Res Treat ; 191(1): 63-75, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34698969

RESUMO

PURPOSE: Invasion of carcinoma cells into surrounding tissue affects breast cancer staging, influences choice of treatment, and impacts on patient outcome. KIF21A is a member of the kinesin superfamily that has been well-studied in congenital extraocular muscle fibrosis. However, its biological relevance in breast cancer is unknown. This study investigated the functional roles of KIF21A in this malignancy and examined its expression pattern in breast cancer tissue. METHODS: The function of KIF21A in breast carcinoma was studied in vitro by silencing its expression in breast cancer cells and examining the changes in cellular activities. Immunohistochemical staining of breast cancer tissue microarrays was performed to determine the expression patterns of KIF21A. RESULTS: Knocking down the expression of KIF21A using siRNA in MDA-MB-231 and MCF7 human breast cancer cells resulted in significant decreases in tumor cell migration and invasiveness. This was associated with reduced Patched 1 expression and F-actin microfilaments. Additionally, the number of focal adhesion kinase- and paxillin-associated focal adhesions was increased. Immunohistochemical staining of breast cancer tissue microarrays showed that KIF21A was expressed in both the cytoplasmic and nuclear compartments of carcinoma cells. Predominance of cytoplasmic KIF21A was significantly associated with larger tumors and high grade cancer, and prognostic of cause-specific overall patient survival and breast cancer recurrence. CONCLUSION: The data demonstrates that KIF21A is an important regulator of breast cancer aggressiveness and may be useful in refining prognostication of this malignant disease.


Assuntos
Neoplasias da Mama , Cinesinas , Neoplasias da Mama/genética , Citoplasma , Feminino , Humanos , Cinesinas/genética , Recidiva Local de Neoplasia/genética , Prognóstico
7.
Breast Cancer Res Treat ; 186(3): 655-665, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33625616

RESUMO

PURPOSE: Breast cancer is the most common type of cancer affecting women worldwide. Phosphoglycerate dehydrogenase (PHGDH) is an oxidoreductase in the serine biosynthesis pathway. Although it has been reported to affect growth of various tumors, its role in breast cancer is largely unknown. This study aimed to analyze the expression of PHGDH in breast cancer tissue samples and to determine if PHGDH regulates breast cancer cell proliferation. METHODS: Tissue microarrays consisting of 305 cases of breast invasive ductal carcinoma were used for immunohistochemical evaluation of PHGDH expression. The role of PHGDH in breast cancer was investigated in vitro by knocking down its expression and determining the effect on cell proliferation and cell cycling, and in ovo by using a chorioallantoic membrane (CAM) assay. RESULTS: Immunohistochemical examination showed that PHGDH is mainly localized in the cytoplasm of breast cancer cells and significantly associated with higher cancer grade, larger tumor size, increased PCNA expression, and lymph node positivity. Analysis of the GOBO dataset of 737 patients demonstrated that increased PHGDH expression was associated with poorer overall survival. Knockdown of PHGDH expression in breast cancer cells in vitro resulted in a decrease in cell proliferation, reduction in cells entering the S phase of the cell cycle, and downregulation of various cell cycle regulatory genes. The volume of breast tumor in an in ovo CAM assay was found to be smaller when PHGDH was silenced. CONCLUSION: The findings suggest that PHGDH has a regulatory role in breast cancer cell proliferation and may be a potential prognostic marker and therapeutic target in breast cancer.


Assuntos
Neoplasias da Mama , Fosfoglicerato Desidrogenase , Neoplasias da Mama/genética , Linhagem Celular Tumoral , Proliferação de Células , Feminino , Humanos , Fosfoglicerato Desidrogenase/genética , Prognóstico , Serina
8.
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
9.
BMC Cancer ; 20(1): 1049, 2020 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-33129287

RESUMO

BACKGROUND: Measurement of serum human epidermal growth factor receptor-2 (HER-2/neu) levels might play an essential role as a diagnostic/screening marker for the early selection of therapeutic approaches and predict prognosis in breast cancer patients. We aimed to undertake a systematic review and meta-analysis focusing on the diagnostic/screening value of serum HER-2 levels in comparison to routine methods. METHODS: We performed a systematic search via PubMed, Scopus, Cochrane-Library, and Web of Science databases for human diagnostic studies reporting the levels of serum HER-2 in breast cancer patients, which was confirmed using the histopathological examination. Meta-analyses were carried out for sensitivity, specificity, accuracy, area under the ROC curve (AUC), positive predictive value (PPV), negative predictive value (NPV), positive likelihood ratio (PLR), and negative likelihood ratio (NLR). RESULTS: Fourteen studies entered into this investigation. The meta-analysis indicated the low sensitivity for serum HER2 levels (Sensitivity: 53.05, 95%CI 40.82-65.28), but reasonable specificity of 79.27 (95%CI 73.02-85.51), accuracy of 72.06 (95%CI 67.04-77.08) and AUC of 0.79 (95%CI 0.66-0.92). We also found a significant differences for PPV (PPV: 56.18, 95%CI 44.16-68.20), NPV (NPV: 76.93, 95%CI 69.56-84.31), PLR (PLR: 2.10, 95%CI 1.69-2.50) and NLR (NLR: 0.58, 95%CI 0.44-0.71). CONCLUSION: Our findings revealed that although serum HER-2 levels showed low se nsitivity for breast cancer diagnosis, its specificity, accuracy and AUC were reasonable. Hence, it seems that the measurement of serum HER-2 levels can play a significant role as a verification test for initial negative screening test results, especially in low-income regions due to its cost-effectiveness and ease of implementation.


Assuntos
Biomarcadores Tumorais/sangue , Neoplasias da Mama/diagnóstico , Receptor ErbB-2/sangue , Neoplasias da Mama/sangue , Feminino , Humanos , Prognóstico
10.
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
11.
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
12.
Int J Cancer ; 135(11): 2579-92, 2014 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-24752740

RESUMO

Heparan sulfate 3-O-sulfotransferase 2 (HS3ST2), an enzyme mediating 3-O-sulfation of heparan sulfate (HS), is silenced by hypermethylation in breast cancer. As HS has an important co-receptor function for numerous signal transduction pathways, the phenotypical changes due to HS3ST2 reexpression were investigated in vitro using high and low invasive breast cancer cell lines. Compared to controls, highly invasive HS3ST2-expressing MDA-MB-231 cells showed enhanced Matrigel invasiveness, transendothelial migration and motility. Affymetrix screening and confirmatory real-time PCR and Western blotting analysis revealed increased expression of several matrix metalloproteinases, cadherin-11, E-cadherin and CEACAM-1, while protease inhibitor and annexin A10 expression were decreased. Low invasive HS3ST2 -expressing MCF-7 cells became even less invasive, with no change in gelatinolytic MMP activity. HS3ST2 expression increased HS-dependent basal and FGF2-specific signaling through the constitutively active p44/42 MAPK pathway in MDA-MB-231 cells. Increased MAPK activation was accompanied by upregulation of ß-catenin in MDA-MB-231, and of the transcription factor Tcf4 in both cell lines. Dysregulation of Tcf4-regulated ion transporters and increased cytosolic acidification were observed in HS3ST2-expressing MDA-MB-231 cells, which is a possible underlying cause of increased chemosensitivity towards doxorubicine and paclitaxel in these cells. This study provides the first in vitro evidence of the involvement of HS3ST2 in breast cancer cell invasion and chemosensitivity.


Assuntos
Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Caderinas/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Sulfotransferases/metabolismo , Proteína 2 Semelhante ao Fator 7 de Transcrição/metabolismo , Fatores de Transcrição/metabolismo , Antineoplásicos/farmacologia , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/genética , Western Blotting , Neoplasias da Mama/tratamento farmacológico , Caderinas/genética , Adesão Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Endotélio Vascular/citologia , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/metabolismo , Feminino , Glicosaminoglicanos/metabolismo , Humanos , Técnicas Imunoenzimáticas , Microscopia de Fluorescência , Proteínas Quinases Ativadas por Mitógeno/genética , Invasividade Neoplásica , Fosforilação , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais , Sulfotransferases/genética , Fator de Transcrição 4 , Proteína 2 Semelhante ao Fator 7 de Transcrição/genética , Fatores de Transcrição/genética , Células Tumorais Cultivadas , beta Catenina/genética , beta Catenina/metabolismo
13.
Mod Pathol ; 27(3): 352-60, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23929266

RESUMO

Treatment of triple-negative invasive breast cancers, defined by the absence of estrogen and progesterone receptors and c-erbB2 expression, remains challenging. Androgen receptor, a member of the nuclear receptor superfamily that is involved in signaling pathways regulating cell proliferation, has been implicated in breast tumorigenesis. We immunohistochemically examined the expression of androgen receptor, basal markers (CK14, 34ßE12) and EGFR in 699 triple-negative invasive breast cancers in tissue microarrays using the streptavidin-biotin method, and correlated the findings with clinical outcome. Positive androgen receptor expression was defined as staining of 1% or more of tumor cell nuclei. Survival outcomes were estimated with the Kaplan-Meier method and compared between groups with log-rank statistics. Cox proportional hazards models were used to determine the effect of androgen receptor on survival outcomes. Immunohistochemical positivity was observed in 38% of tumors, with the proportion of stained tumor cells ranging from 1 to 95% (mean 29%, median 10%). Androgen receptor expression was inversely associated with histologic grade and mitotic score. CK14, 34ßE12 and EGFR confirmed 85% of cases to be basal-like, without significant association of basal-like phenotype with androgen receptor expression. Disease-free survival was significantly better in androgen receptor-positive triple-negative breast cancer, with a trend for improved overall survival. Decreased recurrence likelihood in both triple-negative and basal-like tumors (hazard ratio, 0.704; 95% confidence intervals, 0.498-0.994; P=0.0464; and hazard ratio, 0.675; 95% confidence intervals, 0.468-0.974; P=0.0355, respectively) was noted within 5 years of diagnosis but not thereafter. Our study suggests that loss of androgen receptor in triple-negative breast cancers augurs a worse prognosis, including those with basal-like features. More work in elucidating its relationship with mechanisms of progression, as well as trials of targeted treatment for androgen receptor-expressing triple-negative tumors, needs to be performed.


Assuntos
Biomarcadores Tumorais/análise , Recidiva Local de Neoplasia/metabolismo , Receptores Androgênicos/biossíntese , Neoplasias de Mama Triplo Negativas/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Intervalo Livre de Doença , Feminino , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Pessoa de Meia-Idade , Prognóstico , Modelos de Riscos Proporcionais , Análise Serial de Tecidos , Neoplasias de Mama Triplo Negativas/mortalidade , Neoplasias de Mama Triplo Negativas/patologia
14.
J Hand Microsurg ; 15(5): 365-370, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38152676

RESUMO

Introduction Vessel repair in a chicken thigh is commonly used in microsurgery training model. The sciatic nerve is closely associated with the vessels and has been used for training nerve coaptation, which has different technical considerations from vessel anastomosis. We describe in detail the relevant surgical anatomy and training exercises that can be used with this model. Methods With 32 fresh store-bought chicken thighs, 16 were used to analyze the gross and histological features of the sciatic nerve, and 16 were intended to create and perform training models. Results The average visible length of the nerve in the thigh was 51 mm (standard deviation [SD] 2.57 mm). The average diameter of the nerve was 2 mm (SD 0.33 mm) and was largest at its proximal end (3.21 mm, SD 0.27 mm). The nerve consistently branched into two along the chicken thigh, with more branching subsequently. This simulation model is appropriate not only for the classical end-to-end epineural suture, but also for advanced exercises, in terms of longitudinal fasciculus dissection, mismatched size nerve transfer, injured nerve preparation, and vein conduit technique. Dyeing of nerve fascicles enhanced the visibility of nerve surface quality. Conclusion The sciatic nerve in the chicken thigh is a suitable and accessible model for microsurgery training. The branching and fascicular patterns of the nerve lends itself well to both novice training and advanced simulation. We have incorporated this model into our training curricula.

15.
ACS Nano ; 17(12): 11593-11606, 2023 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-37306553

RESUMO

Present day strategies for delivery of wireless photodynamic therapy (PDT) to deep-seated targets are limited by the inadequacy of irradiance and insufficient therapeutic depth. Here we report the design and preclinical validation of a flexible wireless upconversion nanoparticle (UCNP) implant (SIRIUS) that is capable of large field, high intensity illumination for PDT of deep-seated tumors. The implant achieves this by incorporating submicrometer core-shell-shell NaYF4 UCNPs into its design, which significantly enhances upconversion efficiency and mitigates light loss from surface quenching. We demonstrate the efficacy of SIRIUS UCNP implant mediated PDT in preclinical breast cancer disease models. In our in vitro experiments, SIRIUS directed 5-Aminolevulinic Acid (5-ALA) based wireless PDT leads to significant reactive oxygen species (ROS) generation and tumor apoptosis in hormonal receptor+/HER2+ (MCF7) and triple-negative (MDA-MB-231) breast cancer cell lines. In our in vivo rodent model, SIRIUS-driven PDT is shown to be significant in regressing tumors when applied to orthotopically inoculated breast tumors. Following successful preclinical validation, we also describe a clinical prototype of UCNP breast implant with potential dual cosmetic and onco-therapeutic functions. SIRIUS is an upconversion breast implant for wireless PDT that fulfils all the design prerequisites necessary for seamless clinical translation.


Assuntos
Implantes de Mama , Nanopartículas , Fotoquimioterapia , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Ácido Aminolevulínico , Linhagem Celular Tumoral
16.
Int J Cancer ; 131(6): E884-96, 2012 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-22573479

RESUMO

microRNAs are small endogenous noncoding RNAs, which post-transcriptionally regulate gene expression. In breast cancer, overexpression of the transmembrane heparan sulfate proteoglycan syndecan-1, a predicted target of the oncomiR miR-10b, correlates with poor clinical outcome. To investigate the potential functional relationship of miR-10b and syndecan-1, MDA-MB-231 and MCF-7 breast cancer cells were transiently transfected with pre-miR-10b, syndecan-1 siRNA or control reagents, respectively. Altered cell behavior was monitored by proliferation, migration and invasion chamber assays, and time-lapse video microscopy. miR-10b overexpression induced post-transcriptional downregulation of syndecan-1, as demonstrated by quantitative real-time PCR (qPCR), flow cytometry, and 3'UTR luciferase assays, resulting in increased cancer cell migration and matrigel invasiveness. Syndecan-1 silencing generated a copy of this phenotype. Adhesion to fibronectin and laminin and basal cell proliferation was increased. Syndecan-1 coimmunoprecipitated with focal adhesion kinase, which showed increased activation upon syndecan-1 depletion. Affymetrix screening and confirmatory qPCR and Western blotting analysis of syndecan-1-deficient cells revealed upregulation of ATF-2, COX-2, cadherin-11, vinculin, actin γ 2, MYL9, transgelin-1, RhoA/C, matrix metalloproteinase 2 (MMP2) and heparanase, and downregulation of AML1/RUNX1, E-cadherin, CLDN1, p21WAF/CIP, cyclin-dependent kinase 6, TLR-4, PAI1/2, Collagen1alpha1, JHDM1D, Mpp4, MMP9, matrilin-2 and ANXA3/A10. Video microscopy demonstrated massively increased Rho kinase-dependent motility of syndecan-1-depleted cells, which displayed increased filopodia formation. We conclude that syndecan-1 is a novel target of the oncomiR miR-10b. Rho-GTPase-dependent modulation of cytoskeletal function and downregulation of E-cadherin expression are identified as relevant effectors of the miR-10b-syndecan-1 axis, which emerges as a promising target for the development of new therapeutic approaches for breast cancer.


Assuntos
Neoplasias da Mama/patologia , Caderinas/fisiologia , Movimento Celular , MicroRNAs/fisiologia , Sindecana-1/antagonistas & inibidores , Proteínas rho de Ligação ao GTP/fisiologia , Fator 2 Ativador da Transcrição/genética , Comunicação Celular , Linhagem Celular Tumoral , Subunidade alfa 2 de Fator de Ligação ao Core/genética , Progressão da Doença , Feminino , Humanos , Invasividade Neoplásica , Fosforilação , RNA Mensageiro/análise , RNA Interferente Pequeno/genética , Sindecana-1/fisiologia
17.
Cancers (Basel) ; 15(1)2022 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-36612261

RESUMO

Renal cell carcinoma (RCC) makes up the majority of kidney cancers, with a poor prognosis for metastatic RCC (mRCC). Challenges faced in the management of mRCC, include a lack of reliable prognostic markers and biomarkers for precise monitoring of disease treatment, together with the potential risk of toxicity associated with more recent therapeutic options. Glycosaminoglycans (GAGs) are a class of carbohydrates that can be categorized into four main subclasses, viz., chondroitin sulfate, hyaluronic acid, heparan sulfate and keratan sulfate. GAGs are known to be closely associated with cancer progression and modulation of metastasis by modification of the tumor microenvironment. Alterations of expression, composition and spatiotemporal distribution of GAGs in the extracellular matrix (ECM), dysregulate ECM functions and drive cancer invasion. In this review, we focus on the clinical utility of GAGs as biomarkers for mRCC (which is important for risk stratification and strategizing effective treatment protocols), as well as potential therapeutic targets that could benefit patients afflicted with advanced RCC. Besides GAG-targeted therapies that holds promise in mRCC, other potential strategies include utilizing GAGs as drug carriers and their mimetics to counter cancer progression, and enhance immunotherapy through binding and transducing signals for immune mediators.

18.
Matrix Biol ; 109: 140-161, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35395387

RESUMO

Hyaluronan (HA) is a ubiquitous extracellular matrix component playing a crucial role in the regulation of cell behaviors, including cancer. Aggressive breast cancer cells tend to proliferate, migrate and metastatize. Notably, triple-negative breast cancer cells lacking the expression of estrogen receptor (ER) as well as progesterone receptor and HER2 are more aggressive than ER-positive ones. As currently no targeted therapy is available for triple-negative breast cancer, the identification of novel therapeutic targets has a high clinical priority. In ER-negative cells, tumoral behavior can be reduced by inhibiting HA synthesis or silencing the enzymes involved in its metabolism, such as HA synthase 2 (HAS2). HAS2-AS1 is a long non-coding RNA belonging to the natural antisense transcript family which is known to favor HAS2 gene expression and HA synthesis, thus bolstering malignant progression in brain, ovary, and lung tumors. As the role of HAS2-AS1 has not yet been investigated in breast cancer, in this work we report that ER-positive breast cancers had lower HAS2-AS1 expression compared to ER-negative tumors. Moreover, the survival of patients with ER-negative tumors was higher when the expression of HAS2-AS1 was elevated. Experiments with ER-negative cell lines as MDA-MB-231 and Hs 578T revealed that the overexpression of either the full-length HAS2-AS1 or its exon 2 long or short isoforms alone, strongly reduced cell viability, migration, and invasion, whereas HAS2-AS1 silencing increased cell aggressiveness. Unexpectedly, in these ER-negative cell lines, HAS2-AS1 is involved neither in the regulation of HAS2 nor in HA deposition. Finally, transcriptome analysis revealed that HAS2-AS1 modulation affected several pathways, including apoptosis, proliferation, motility, adhesion, epithelial to mesenchymal transition, and signaling, describing this long non-coding RNA as an important regulator of breast cancer cells aggressiveness.


Assuntos
Neoplasias da Mama , RNA Longo não Codificante , Neoplasias de Mama Triplo Negativas , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Transição Epitelial-Mesenquimal , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Hialuronan Sintases/genética , Hialuronan Sintases/metabolismo , Ácido Hialurônico/metabolismo , RNA Longo não Codificante/genética , Neoplasias de Mama Triplo Negativas/genética
19.
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
20.
Curr Med Chem ; 28(25): 5034-5047, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34139972

RESUMO

The Interferon-induced protein with tetratricopeptide repeats (IFIT) family is an important component of the antiviral immune response. There are currently four known IFIT family members in humans, namely IFIT1, IFIT2, IFIT3 and IFIT5. Recent discoveries have brought attention to the significant roles of IFITs in cancer. This review summarises current knowledge on the biological roles of different IFIT proteins in various types of malignant neoplasm, and highlights the potential use of these molecules as cancer biomarkers and prognostic factors.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Proteínas Reguladoras de Apoptose , Peptídeos e Proteínas de Sinalização Intracelular , Proteínas de Neoplasias , Neoplasias , Proteínas de Ligação a RNA , Proteínas Adaptadoras de Transdução de Sinal/fisiologia , Antivirais , Proteínas Reguladoras de Apoptose/fisiologia , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/fisiologia , Proteínas de Neoplasias/fisiologia , Neoplasias/tratamento farmacológico , Neoplasias/genética , Proteínas , Proteínas de Ligação a RNA/fisiologia , Repetições de Tetratricopeptídeos
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