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1.
J Transl Med ; 17(1): 435, 2019 12 30.
Artigo em Inglês | MEDLINE | ID: mdl-31888645

RESUMO

BACKGROUND: Breast cancer (BrC) remains the leading cause of cancer-related death in women, mainly due to recurrent and/or metastatic events, entailing the need for biomarkers predictive of progression to advanced disease. MicroRNAs hold promise as noninvasive cancer biomarkers due to their inherent stability and resilience in tissues and bodily fluids. There is increasing evidence that specific microRNAs play a functional role at different steps of the metastatic cascade, behaving as signaling mediators to enable the colonization of a specific organ. Herein, we aimed to evaluate the biomarker performance of microRNAs previously reported as associated with prognosis for predicting BrC progression in liquid biopsies. METHODS: Selected microRNAs were assessed using a quantitative reverse transcription-polymerase chain reaction in a testing cohort of formalin-fixed paraffin-embedded primary (n = 16) and metastatic BrC tissues (n = 22). Then, miR-30b-5p and miR-200b-3p were assessed in a validation cohort #1 of formalin-fixed paraffin-embedded primary (n = 82) and metastatic BrC tissues (n = 93), whereas only miR-30b-5p was validated on a validation cohort #2 of liquid biopsies from BrC patients with localized (n = 20) and advanced (n = 25) disease. ROC curve was constructed to evaluate prognostic performance. RESULTS: MiR-30b-5p was differentially expressed in primary tumors and paired metastatic lesions, with bone metastases displaying significantly higher miR-30b-5p expression levels, paralleling the corresponding primary tumors. Interestingly, patients with advanced disease disclosed increased circulating miR-30b-5p expression compared to patients with localized BrC. CONCLUSIONS: MiR-30b-5p might identify BrC patients at higher risk of disease progression, thus, providing a useful clinical tool for patients' monitoring, entailing earlier and more effective treatment. Nonetheless, validation in larger multicentric cohorts is mandatory to confirm these findings.


Assuntos
Neoplasias da Mama/sangue , Neoplasias da Mama/patologia , MicroRNA Circulante/sangue , MicroRNA Circulante/genética , Regulação Neoplásica da Expressão Gênica , MicroRNAs/sangue , MicroRNAs/genética , Adulto , Idoso , Biomarcadores Tumorais/sangue , Biomarcadores Tumorais/genética , Neoplasias da Mama/genética , Estudos de Coortes , Feminino , Humanos , Biópsia Líquida , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Curva ROC
2.
Clin Neurol Neurosurg ; 197: 106150, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32920499

RESUMO

BACKGROUND: Breast cancer (BC) is one of the commonest causes of brain metastases (BM): approximately 10-16 % of patients diagnosed with metastatic breast cancer will eventually develop BM during the course of their disease, however, certain subtypes have a higher risk of this event. The aim of this analysis was therefore to evaluate the prognosis and the pattern and imaging features of BM according to different BC subtypes. PATIENTS AND METHODS: We retrospectively reviewed the case records of patients with breast cancer and evidence of brain metastases from the database of IPO Porto between 2014-2018. The data obtained were statistically analysed. RESULTS: We analysed 147 patients with BM from BC. The triple-negative subtype had the shortest overall survival (OS) after BM, besides a short period of time between BC and BM. HER2 overexpressing tumors had the longest OS. The estrogen-receptor positive group had the greatest interval between initial BC diagnosis and diagnosis of BM. Larger lesions showed a heterogeneous contrast enhancement and were heterogeneous pn T2WI sequences; a hyposignal on T2*WI was also associated with larger lesions. Triple-negative BC tended to have more heterogeneous lesions on T1WI. We noticed that the hippocampus is rarely affected by metastatic lesions. CONCLUSIONS: Based on the BC subtype it is possible to make a prediction about the prognosis of the disease and some imaging features of the BM, but not about their pattern of distribution. These data support further research concerning prevention, early detection, and treatment of BM from BC.


Assuntos
Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/secundário , Neoplasias da Mama/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Encéfalo/diagnóstico por imagem , Neoplasias Encefálicas/patologia , Feminino , Humanos , Pessoa de Meia-Idade , Estudos Retrospectivos , Análise de Sobrevida
3.
Oncol Rep ; 41(3): 1431-1438, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30664168

RESUMO

Notwithstanding the marked progress in breast cancer (BC) management, it still constitutes the most common malignancy in women and a major cause of morbidity and mortality, thus remaining a major health issue worldwide. Most BC cases are hormone receptor (HR) positive (luminal A or B molecular subtypes) and endocrine treatment (ET) is an important therapeutic modality at all disease stages. Nevertheless, despite substantial improvements in BC patient outcome, effectiveness of ET is limited, as up to 40% of patients eventually relapse or progress and endocrine resistant BC has a less favorable prognosis and constitutes a therapeutic challenge. The biological mechanisms underlying endocrine resistance are, however, still poorly understood. In this review, we focused on data regarding the main epigenetic mechanisms associated with the development of endocrine treated­resistant BC described so far, including alterations in DNA methylation, non­coding RNAs, chromatin remodeling, post­translational histone modifications and histone variants. Notably, specific epigenetic alterations have been characterized in this subset of breast tumors and may be of clinical value for individualized patient management in the future.


Assuntos
Antineoplásicos Hormonais/farmacologia , Biomarcadores Tumorais/genética , Neoplasias da Mama/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos/genética , Epigênese Genética , Antineoplásicos Hormonais/uso terapêutico , Neoplasias da Mama/genética , Montagem e Desmontagem da Cromatina , Metilação de DNA/genética , Feminino , Código das Histonas/genética , Histonas/genética , Histonas/metabolismo , Humanos , Processamento de Proteína Pós-Traducional/genética , RNA não Traduzido/genética
4.
Front Genet ; 10: 815, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31572437

RESUMO

Breast cancer (BrC) is the most frequent malignancy and the leading cause of cancer death among women worldwide. Approximately 70% of BrC are classified as luminal-like subtype, expressing the estrogen receptor. One of the most common and effective adjuvant therapies for this BrC subtype is endocrine therapy. However, its effectiveness is limited, with relapse occurring in up to 40% of patients. Because microRNAs have been associated with several mechanisms underlying endocrine resistance and sensitivity, they may serve as predictive and/or prognostic biomarkers in this setting. Hence, the main goal of this study was to investigate whether miRNAs deregulated in endocrine-resistant BrC may be clinically relevant as prognostic and predictive biomarkers in patients treated with adjuvant endocrine therapy. A global expression assay allowed for the identification of microRNAs differentially expressed between luminal BrC patients with or without recurrence after endocrine adjuvant therapy. Then, six microRNAs were chosen for validation using quantitative reverse transcription polymerase chain reaction in a larger set of tissue samples. Thus, miR-30c-5p, miR-30b-5p, miR-182-5p, and miR-200b-3p were found to be independent predictors of clinical benefit from endocrine therapy. Moreover, miR-182-5p and miR-200b-3p displayed independent prognostic value for disease recurrence in luminal BrC patients after endocrine therapy. Our results indicate that selected miRNAs' panels may constitute clinically useful ancillary tools for management of luminal BrC patients. Nevertheless, additional validation, ideally in a multicentric setting, is required to confirm our findings.

5.
Cancers (Basel) ; 10(10)2018 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-30261643

RESUMO

BACKGROUND: Breast (BrC), colorectal (CRC) and lung (LC) cancers are the three most common and deadly cancers in women. Cancer screening entails an increase in early stage disease detection but is hampered by high false-positive rates and overdiagnosis/overtreatment. Aberrant DNA methylation occurs early in cancer and may be detected in circulating cell-free DNA (ccfDNA), constituting a valuable biomarker and enabling non-invasive testing for cancer detection. We aimed to develop a ccfDNA methylation-based test for simultaneous detection of BrC, CRC and LC. METHODS: CcfDNA from BrC, CRC and LC patients and asymptomatic controls were extracted from plasma, sodium-bisulfite modified and whole-genome amplified. APC, FOXA1, MGMT, RARß2, RASSF1A, SCGB3A1, SEPT9, SHOX2 and SOX17 promoter methylation levels were determined by multiplex quantitative methylation-specific PCR. Associations between methylation and standard clinicopathological parameters were assessed. Biomarkers' diagnostic performance was also evaluated. RESULTS: A "PanCancer" panel (APC, FOXA1, RASSF1A) detected the three major cancers with 72% sensitivity and 74% specificity, whereas a "CancerType" panel (SCGB3A1, SEPT9 and SOX17) indicated the most likely cancer topography, with over 80% specificity, although with limited sensitivity. CONCLUSIONS: CcfDNA's methylation assessment allows for simultaneous screening of BrC, CRC and LC, complementing current modalities, perfecting cancer suspects' triage, increasing compliance and cost-effectiveness.

6.
J Clin Med ; 7(11)2018 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-30405052

RESUMO

BACKGROUND: Breast cancer (BrC) is the most frequent neoplasm in women. New biomarkers, including aberrant DNA methylation, may improve BrC management. Herein, we evaluated the detection and prognostic performance of seven genes' promoter methylation (APC, BRCA1, CCND2, FOXA1, PSAT1, RASSF1A and SCGB3A1). METHODS: Methylation levels were assessed in primary BrC tissues by quantitative methylation-specific polymerase chain reaction (QMSP) and in circulating cell-free DNA (ccfDNA) by multiplex QMSP from two independent cohorts of patients (Cohort #1, n = 137; and Cohort #2, n = 44). Receiver operating characteristic (ROC) curves were constructed, and log-rank test and Cox regression were performed to assess the prognostic value of genes' methylation levels. RESULTS: The gene-panel APC, FOXA1, RASSF1A, SCGB3A1 discriminated normal from cancerous tissue with high accuracy (95.55%). In multivariable analysis, high PSAT1-methylation levels [>percentile 75 (P75)] associated with longer disease-free survival, whereas higher FOXA1-methylation levels (>P75) associated with shorter disease-specific survival. The best performing panel in ccfDNA (APC, FOXA1 and RASSF1A) disclosed a sensitivity, specificity and accuracy over 70%. CONCLUSIONS: This approach enables BrC accurate diagnosis and prognostic stratification in tissue samples, and allows for early detection in liquid biopsies, thus suggesting a putative value for patient management.

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