RESUMO
The potential role of circulating microRNAs (miRNAs) as biomarkers in breast cancer (BC) management has been widely reported. However, the numerous discrepancies between studies in this regard hinders the implementation of circulating miRNAs in routine clinical practice. In the context of BC patients undergoing neoadjuvant chemotherapy (NAC), the possibility of predicting NAC response may lead to prognostic improvements by individualizing post-neoadjuvant therapy. In this context, the present meta-analysis aims to clarify circulating miRNAs' predictive role with respect to NAC response among BC patients. We conducted a comprehensive literature search on five medical databases until 16 February 2023. We pooled the effect sizes of each study by applying a random-effects model. Cochran's Q test (p-level of significance set at 0.05) scores and I2 values were assessed to determine between-study heterogeneity. The PROBAST (Prediction Model Risk of Bias Assessment Tool) tool was used to evaluate the selected studies' risk of bias. Overall, our findings support the hypothesis that circulating miRNAs, specifically miR-21-5p and miR-155-5p, may act as predictive biomarkers in the neoadjuvant setting among BC patients. However, due to the limited number of studies included in this meta-analysis and the high degrees of clinical and statistical heterogeneity, further research is required to confirm the predictive power of circulating miR-21-5p and miR-155-5p.
RESUMO
Accumulating epidemiological studies have investigated a possible interconnection between migraine (Mi) and breast cancer (BC) because of the strong link between these diseases and female reproductive hormones. This review aims to consolidate findings from epidemiological studies and explore biologically plausible hypothetical mechanisms related to hormonal pathways. Current evidence suggests a protective role of Mi in BC development, particularly in case-control studies but not in cohort ones. The inconsistency among studies may be due to several reasons, including diagnostic criteria for Mi and the age gap between the development of these two diseases. Furthermore, recent research has challenged the concept of a net beneficial effect of Mi on BC, suggesting a more complex relationship between the two conditions. Many polymorphisms/mutations in hormone-related pathways are involved in at least one of the two conditions. The most promising evidence has emerged for a specific alteration in the estrogen receptor 1 gene (rs2228480). However, the possible specific mutation or polymorphism involved in this association has not yet been identified. Further studies with robust methodologies are needed to validate the protective role of Mi in BC and fully elucidate the precise nature of this causal relationship.
RESUMO
Recently, circulating microRNAs (miRNAs) have emerged as potential non-invasive biomarkers for breast cancer (BC) management. In the context of BC patients undergoing neoadjuvant chemotherapy (NAC), the possibility of obtaining repeated, non-invasive biological samples from patients before, during, and after treatment is incredibly convenient and provides the opportunity to investigate circulating miRNAs as diagnostic, predictive, and prognostic tools. The present review aims to summarize major findings in this setting, thus highlighting their potential applicability in daily clinical practice and their possible limitations. In all the contexts (diagnostic, predictive, and prognostic), circulating miR-21-5p and miR-34a-5p have emerged as the most promising non-invasive biomarkers for BC patients undergoing NAC. Specifically, their high baseline level could discriminate between BC patients and healthy controls. On the other hand, in predictive and prognostic investigations, low circulating miR-21-5p and miR-34a-5p levels may identify patients with better outcomes, in terms of both treatment response and invasive disease-free survival. However, the findings in this field have been very heterogeneous. Indeed, pre-analytical and analytical variables, as well as factors related to patients, may explain the inconsistency among different study results. Thus, further clinical trials, with more precise patient inclusion criteria and more standardized methodological approaches, are definitely needed to better define the potential role of these promising non-invasive biomarkers.
RESUMO
INTRODUCTION: The interaction between breast cancer and migraine is complex and not fully elucidated. Large epidemiological studies point towards a beneficial effect of migraines on breast cancer (BC). We aimed to investigate the BC-migraine relationship, with strict data checks and clinical evaluations of both BC and common headache forms. METHODS: Consecutive BC patients were evaluated with the International Classification of Headache Disorders. Clinical data on the BC subtypes and treatments were collected. Parametric and nonparametric statistics were used according to data distributions. RESULTS: Fifty patients were recruited. The mean age was 53.5 ± 12.5 years; 42% were postmenopausal, 52% were premenopausal, and 6% were peri-menopausal. Eleven patients were diagnosed as luminal A, nine as luminal B, 24 as HER2-positive (HER2 +), six as triple-negative BC. Thirty-eight (76%) patients had hormone receptor-positive disease. Ninety-two percent received chemotherapy, 66% received endocrine therapy, and 52% received radiotherapy. Nine out of 50 reported a worsening of headache after systemic treatment. Migraine was diagnosed in 29 patients (18 with menstrual migraine), tension-type headache (TTH) in nine, and no headache in 12. Patients with migraine were younger (48.4 ± 10.7 vs. 60.5 ± 12; p < 0.01). Patients with migraine and TTH had a higher chance of having a HER2 + BC (p < 0.05). Active migraine was associated with a higher expression of estrogen receptors (p = 0.04). CONCLUSIONS: Patients with active migraine had higher estrogen receptor expression, while migraine and TTH patients mainly had HER2 + BC. This association was not known earlier and could be helpful to understand deeper the relationship between BC and headache.
