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Triple-negative breast cancer is aggressive and challenging to treat because of a lack of targets and heterogeneity among tumors. A paramount factor in the mortality from breast cancer is metastasis, which is driven by genetic and phenotypic alterations that drive epithelial-mesenchymal transition, stemness, survival, migration and invasion. Many genetic and epigenetic mechanisms have been identified in triple-negative breast cancer that drive these metastatic phenotypes; however, this knowledge has not yet led to the development of effective drugs for metastatic triple-negative breast cancer (mTNBC). One that may not have received enough attention in the literature is post-translational regulation of broad sets of cancer-related genes through inhibitory microRNAs and the complex competitive endogenous RNA (ceRNA) regulatory networks they are influenced by. This field of study and the resulting knowledge regarding alterations in these networks is coming of age, enabling translation into clinical benefit for patients. Herein, we review metastatic triple-negative breast cancer (mTNBC), the role of ceRNA network regulation in metastasis (and therefore clinical outcomes), potential approaches for therapeutic exploitation of these alterations, knowledge gaps and future directions in the field.

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Resistance to therapy is a persistent problem that leads to mortality in breast cancer, particularly triple-negative breast cancer (TNBC). MiRNAs have become a focus of investigation as tissue-specific regulators of gene networks related to drug resistance. Circulating miRNAs are readily accessible non-invasive potential biomarkers for TNBC diagnosis, prognosis, and drug-response. Our aim was to use systems biology, meta-analysis, and network approaches to delineate the drug resistance pathways and clinical outcomes associated with circulating miRNAs in TNBC patients. MiRNA expression analysis was used to investigate differentially regulated circulating miRNAs in TNBC patients, and integrated pathway regulation, gene ontology, and pharmacogenomic network analyses were used to identify target genes, miRNAs, and drug interaction networks. Herein, we identified significant differentially expressed circulating miRNAs in TNBC patients (miR-19a/b-3p, miR-25-3p, miR-22-3p, miR-210-3p, miR-93-5p, and miR-199a-3p) that regulate several molecular pathways (PAM (PI3K/Akt/mTOR), HIF-1, TNF, FoxO, Wnt, and JAK/STAT, PD-1/PD-L1 pathways and EGFR tyrosine kinase inhibitor resistance (TKIs)) involved in drug resistance. Through meta-analysis, we demonstrated an association of upregulated miR-93, miR-210, miR-19a, and miR-19b with poor overall survival outcomes in TNBC patients. These results identify miRNA-regulated mechanisms of drug resistance and potential targets for combination with chemotherapy to overcome drug resistance in TNBC. We demonstrate that integrated analysis of multi-dimensional data can unravel mechanisms of drug-resistance related to circulating miRNAs, particularly in TNBC. These circulating miRNAs may be useful as markers of drug response and resistance in the guidance of personalized medicine for TNBC.

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BACKGROUND: There is a paucity of literature examining the impact of timing of surgery after neoadjuvant chemotherapy. OBJECTIVE: This study aimed to analyze the impact of the time taken to initiate surgical treatment following completion of neoadjuvant chemotherapy on patients' outcomes by evaluating their pathological response, overall survival (OS), and disease-free survival (DFS). METHODS: This is a retrospective review of 611 patients diagnosed with stage II and III breast cancer that received neoadjuvant chemotherapy and surgery between January 2004 and December 2014. The data was collected from a prospectively gathered registry. The patients were stratified into three cohorts according to the time of surgery after neoadjuvant chemotherapy: <4 weeks, 4-7 weeks, or ≥8 weeks. Outcomes were assessed using Kaplan-Meier curves, and the variables were compared using log-rank statistics. RESULTS: The 5-year OS rate was 89.6% and the 5-year DFS rate was 74%. OS and DFS were not significantly different when stratified according to timing of surgery; however, the trends of OS and DFS were poor when surgery was delayed for ≥8 weeks. Median OS and median DFS have not yet been reached. Of the 17% of patients that had surgery after ≥8 weeks, 12.9% had pathological complete response (pCR), while among those that received surgery 4-7 weeks and <4 weeks after neoadjuvant chemotherapy, 26% and 21% had pCR, respectively (p = 0.02). ER+/HER-2+ patients had a statistically significant decrease in pCR if surgery was performed after ≥8 weeks. CONCLUSION: Our patients showed improved pCR if surgery was performed within 8 weeks, especially for ER+/HER-2+ patients. All patients had better OS and DFS trends if surgery was performed between 4 and 7 weeks after neoadjuvant chemotherapy.

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BACKGROUND: First aid is the first and most essential life saving care that can reduce the morbidity of an individual in a health-threatening circumstance. The aim of this study was to assess the knowledge and attitude toward the provision of first aid among students attending Princess Norah University (PNU). MATERIALS AND METHODS: A cross-sectional study was conducted at PNU in Riyadh, Saudi Arabia, from October 2017 to December 2017. A total of 1000 female students from 15 different colleges completed a self-administered questionnaire. RESULTS: The mean age was 21 years (range 18-26); 36% study participants were from health colleges and remaining from other colleges. Only 34.7% had good knowledge, 57.5% had moderate knowledge, and 7.8% had poor knowledge on first aid skills. Analysis of knowledge in specific emergency situations showed that the students were more knowledgeable in cases of epistaxis, ingestion of toxins, burns, hypoglycemia, and loss of consciousness. However, they were found to be less knowledgeable in handling situations of seizures, choking, and snake bite. About 20.2% of the students had encountered situations where cardiopulmonary resuscitation was required and 65.3% of these students had not provided first aid because of the lack of knowledge, nervousness, and other issues. Good knowledge was associated with previous first aid training and being a student in a health college. CONCLUSION: Overall, students had a positive attitude toward first aid; however, they still did not have the knowledge necessary to be able to act in emergency situations. There is a need for increased public health awareness. It is also advisable to introduce first aid courses in all universities and secondary schools.

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BACKGROUND: Female breast cancer is frequently diagnosed at a later stage and the leading cause of cancer deaths world-wide. Levels of cell-free circulating microRNAs (miRNAs) can potentially be used as biomarkers to measure disease progression in breast cancer patients in a non-invasive way and are therefore of high clinical value. METHODS: Using quantitative RT-PCR, circulating miRNAs were measured in blood samples collected from disease-free individuals (n = 34), triple-negative breast tumours (TNBC) (n = 36) and luminal tumours (n = 57). In addition to intergroup comparisons, plasma miRNA expression levels of all groups were analyzed against RNASeq data from cancerous breast tissue via The Cancer Genome Atlas (TCGA). RESULTS: A differential set of 18 miRNAs were identified in the plasma of breast cancer patients and 10 miRNAs were uniquely identified based on ROC analysis. The most striking findings revealed elevated tumor suppressor let-7 miRNA in luminal breast cancer patients, irrespective of subtype, and elevated miR-195 in plasma of TNBC breast cancer patients. In contrast, hsa-miR-195 and let-7 miRNAs were absent from cancerous TCGA tissue and strongly expressed in surrounding non-tumor tissue indicating that cancerous cells may selectively export tumor suppressor hsa-miR-195 and let-7 miRNAs in order to maintain oncogenesis. CONCLUSIONS: While studies have indicated that the restoration of let-7 and miR-195 may be a potential therapy for cancer, these results suggested that tumor cells may selectively export hsa-miR-195 and let-7 miRNAs thereby neutralizing their potential therapeutic effect. However, in order to facilitate earlier detection of breast cancer, blood based screening of hsa-miR-195 and let-7 may be beneficial in a female patient cohort.

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