The interaction between tumor cells and their microenvironment is an essential aspect of tumor development. Therefore, understanding how this microenvironment communicates with tumor cells is crucial for the development of new anti-cancer therapies. MicroRNAs (miRNAs) are small non-coding RNAs that inhibit gene expression. They are secreted into the extracellular medium in vesicles called exosomes, which allow communication between cells via the transfer of their cargo. Consequently, we hypothesized that circulating endothelial miRNAs could be transferred to tumor cells and modify their phenotype. Using exogenous miRNA, we demonstrated that endothelial cells can transfer miRNA to tumor cells via exosomes. Using miRNA profiling, we identified miR-503, which exhibited downregulated levels in exosomes released from endothelial cells cultured under tumoral conditions. The modulation of miR-503 in breast cancer cells altered their proliferative and invasive capacities. We then identified two targets of miR-503, CCND2 and CCND3. Moreover, we measured increased plasmatic miR-503 in breast cancer patients after neoadjuvant chemotherapy, which could be partly due to increased miRNA secretion by endothelial cells. Taken together, our data are the first to reveal the involvement of the endothelium in the modulation of tumor development via the secretion of circulating miR-503 in response to chemotherapy treatment.

Background: Over time, the chance of cure after the diagnosis of breast cancer has been increasing, as a consequence of earlier diagnosis, improved diagnostic procedures and more effective treatment options. However, oncologists are concerned by the risk of long term treatment side effects, including congestive heart failure (CHF). Methods: In this study, we evaluated innovative circulating cardiac biomarkers during and after anthracycline-based neoadjuvant chemotherapy (NAC) in breast cancer patients. Levels of cardiac-specific troponins T (cTnT), N-terminal natriuretic peptides (NT-proBNP), soluble ST2 (sST2) and 10 circulating microRNAs (miRNAs) were measured.

Circulating microRNAs (miRNAs) are increasingly recognized as powerful biomarkers in several pathologies, including breast cancer. Here, their plasmatic levels were measured to be used as an alternative screening procedure to mammography for breast cancer diagnosis.A plasma miRNA profile was determined by RT-qPCR in a cohort of 378 women. A diagnostic model was designed based on the expression of 8 miRNAs measured first in a profiling cohort composed of 41 primary breast cancers and 45 controls, and further validated in diverse cohorts composed of 108 primary breast cancers, 88 controls, 35 breast cancers in remission, 31 metastatic breast cancers and 30 gynecologic tumors.A receiver operating characteristic curve derived from the 8-miRNA random forest based diagnostic tool exhibited an area under the curve of 0.81. The accuracy of the diagnostic tool remained unchanged considering age and tumor stage. The miRNA signature correctly identified patients with metastatic breast cancer. The use of the classification model on cohorts of patients with breast cancers in remission and with gynecologic cancers yielded prediction distributions similar to that of the control group.Using a multivariate supervised learning method and a set of 8 circulating miRNAs, we designed an accurate, minimally invasive screening tool for breast cancer.

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Circulating microRNAs (miRNAs) have been extensively studied in cancer as biomarkers but little is known regarding the influence of anti-cancer drugs on their expression levels. In this article, we describe the modifications of circulating miRNAs profile after neoadjuvant chemotherapy (NAC) for breast cancer. The expression of 188 circulating miRNAs was assessed in the plasma of 25 patients before and after NAC by RT-qPCR. Two miRNAs, miR-34a and miR-122, that were significantly increased after NAC, were measured in tumor tissue before and after chemotherapy in 7 patients with pathological partial response (pPR) to NAC. These two chemotherapy-induced miRNAs were further studied in the plasma of 22 patients with adjuvant chemotherapy (AC) as well as in 12 patients who did not receive any chemotherapy. Twenty-five plasma miRNAs were modified by NAC. Among these miRNAs, miR-34a and miR-122 were highly upregulated, notably in pPR patients with aggressive breast cancer. Furthermore, miR-34a level was elevated in the remaining tumor tissue after NAC treatment. Studying the kinetics of circulating miR-34a and miR-122 expression during NAC revealed that their levels were especially increased after anthracycline-based chemotherapy. Comparisons of the plasma miRNA profiles after NAC and AC suggested that chemotherapy-induced miRNAs originated from both tumoral and non-tumoral compartments. This study is the first to demonstrate that NAC specifically induces miRNA expression in plasma and tumor tissue, which might be involved in the anti-tumor effects of chemotherapy in breast cancer patients.

Non-coding RNAs (ncRNA) represent 1/5 of the mammalian transcript number, and 90% of the genome length is transcribed. Many ncRNAs play a role in cancer. Among them, non-coding natural antisense transcripts (ncNAT) are RNA sequences that are complementary and overlapping to those of either protein-coding (PCT) or non-coding transcripts. Several ncNATs were described as regulating protein coding gene expression on the same loci, and they are expected to act more frequently in cis compared to other ncRNAs that commonly function in trans. In this work, 22 breast cancers expressing estrogen receptors and their paired adjacent non-malignant tissues were analyzed by strand-specific RNA sequencing. To highlight ncNATs potentially playing a role in protein coding gene regulations that occur in breast cancer, three different data analysis methods were used: differential expression analysis of ncNATs between tumor and non-malignant tissues, differential correlation analysis of paired ncNAT/PCT between tumor and non-malignant tissues, and ncNAT/PCT read count ratio variation between tumor and non-malignant tissues. Each of these methods yielded lists of ncNAT/PCT pairs that were enriched in survival-associated genes. This work highlights ncNAT lists that display potential to affect the expression of protein-coding genes involved in breast cancer pathology.

In current clinical practices, up to 27% of all breast cancer patients receive neoadjuvant chemotherapy. High pathological complete response rate is frequently associated with tumor-infiltrating lymphocytes. Additionally, circulating immune cells are also often linked to chemotherapy response.We performed a retrospective analysis on a cohort of 112 breast cancer patients (79 triple-negative, 33 hormone receptor-negative/HER2-positive) treated with standard neoadjuvant chemotherapy. Eosinophil and lymphocyte counts were collected from whole blood at baseline and during follow-ups and their associations with pathological complete response, relapse, disease-free and breast cancer-specific survival were analyzed.We observed a higher pathological complete response rate in patients who presented at baseline a relative eosinophil count ≥ 1.5% (55.6%) than in those with a relative eosinophil count < 1.5% (36.2%)(p = 0.04). An improvement in breast cancer-specific survival in patients with high relative eosinophil count (p = 0.05; HR = 0.336; 95% CI = 0.107–1.058) or with high relative lymphocyte count (threshold = 17.5%, p = 0.01; HR = 0.217; 95% CI = 0.060–0.783) were also observed. Upon combining the two parameters into the eosinophil x lymphocyte product with a threshold at 35.8, associations with pathological complete response (p = 0.002), relapse (p = 0.028), disease-free survival (p = 0.012) and breast cancer-specific survival (p = 0.001) were also recorded.In conclusion, the relative eosinophil count and eosinophil x lymphocyte product could be promising, affordable and accessible new biomarkers that are predictive for neoadjuvant chemotherapy response and prognostic for longer survival in triple-negative and hormone receptors-negative/HER2-positive breast cancers. Confirmation of these results in a larger patient population is needed.

2004 Background: Patients with newly diagnosed glioblastoma receive postoperative standard therapy with radiotherapy (RT), and concomitant and up to six cycles of maintenance temozolomide (TMZ) chemotherapy (TMZ/RT→TMZ). Marizomib is a novel, irreversible and brain-penetrant pan-proteasome inhibitor with encouraging findings in preclinical models and early-stage clinical trials for patients with newly diagnosed and recurrent glioblastoma. Therefore, a phase 3 trial was designed to explore the activity of marizomib in addition to TMZ/RT→TMZ. ClinicalTrials.gov Identifier: NCT03345095 Methods: EORTC 1709/CCTG CE.8 is a multicenter, randomized, controlled, open label phase 3 superiority trial. Eligibility criteria included histologically confirmed newly diagnosed glioblastoma and a Karnofsky performance status (KPS) > 70. Eligible patients were stratified for institution, age, KPS as well as extent of surgery, and centrally randomized in a 1:1 ratio. The primary objective of this study is to compare overall survival (OS) in patients receiving marizomib in addition to standard treatment with patients receiving standard treatment only. Secondary endpoints include progression-free survival (PFS), safety, neurocognitive function, and quality of life. Results: The study was opened at 49 EORTC sites in Europe, 23 CCTG sites in Canada, and 8 sites in the US. Patient enrolment started in June 2018 and was close to completion at the time of a planned interim analysis in September 2020. A total of 749 patients (of the planned 750) were randomized when the IDMC recommended to discontinue enrollment. Age, KPS and extent of resection were well balanced between the 2 study arms. No difference in median OS was observed between the standard arm (15.9 months) and the marizomib arm (15.7 months; HR = 0.99). Median PFS was 6.1 vs. 6.2 months (HR = 1.02). Patients in the marizomib group had more often grade 3/4 treatment-emergent adverse events (TEAE) compared to the standard therapy group (42.6% vs. 20.5%), including ataxia, hallucinations and headache. Conclusions: The addition of marizomib to standard radiochemotherapy did not improve OS or PFS in patients with newly diagnosed glioblastoma. Final survival analyses including determination of MGMT promoter methylation status and analyses of other secondary endpoints are ongoing. Clinical trial information: NCT03345095.