Circulating miR-19a and miR-205 in serum may predict the sensitivity of luminal A subtype of breast cancer patients to neoadjuvant chemotherapy with epirubicin plus paclitaxel

The impact of microRNAs on the resistance of breast cancer subtypes to chemotherapy

Breast cancer (BC) formation is primarily influenced by genetics, epigenetics and environmental factors. Aberrant Genetics and epigenetics leads to a condition known as heterogeneity. The heterogeneity of BC can be divided into several subtypes. Among the epigenetic factors, microRNAs (miRNAs) have been shown to play a crucial role in the development and progression of malignancies. These small non-coding RNAs regulate gene expression through a variety of mechanisms, resulting in either mRNA degradation or translation repression. As miRNAs directly control many proteins, genetic anomalies affect tumor metastasis, apoptosis, proliferation, and cell transportation. Consequently, miRNA dysregulations contribute not only in cancer development but also in invasiveness, proliferation rate and more importantly, drug response. Findings mostly indicate subtype-specified identical miRNA profile in BC. Among the BC subtypes, TNBC, HER2 + and luminal are the most resistant to therapy, respectively. Therapy resistance is greatly associated with miRNA expression profile. Hence, concentration of miRNA is the first marker of its role in chemotherapy response. Overexpressed miRNAs may disrupt drug efflux transporters and decrease the drug accumulation in cell. While down-regulated miRNAs which mediate drug resistance processes are mostly correlated with poor treatment response. Moreover, other mechanisms in which miRNAs play crucial roles in chemoresistance such as cell receptor mediations, dysregulation by environmental factors, DNA defects, etc. Recently, several miRNA-based treatments have shown promising results in cancer treatment. Inhibition of up-regulated miRNAs is one of these therapeutic approaches whilst transfecting cell with down-regulated miRNAs also show promising results. Moreover, drug-resistance could also be determined while in the pre-treatment phase via expression levels of miRNAs. Therefore, miRNAs provide intriguing insights and challenges in overcoming chemoresistance. In this article, we have discussed how miRNAs regulate breast cancer subtypes-specific chemoresistance.

Unlocking the Potential of Circulating miRNAs in the Breast Cancer Neoadjuvant Setting: A Systematic Review and Meta-Analysis

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.

Harnessing Epigenetics for Breast Cancer Therapy: The Role of DNA Methylation, Histone Modifications, and MicroRNA

Breast cancer exhibits various epigenetic abnormalities that regulate gene expression and contribute to tumor characteristics. Epigenetic alterations play a significant role in cancer development and progression, and epigenetic-targeting drugs such as DNA methyltransferase inhibitors, histone-modifying enzymes, and mRNA regulators (such as miRNA mimics and antagomiRs) can reverse these alterations. Therefore, these epigenetic-targeting drugs are promising candidates for cancer treatment. However, there is currently no effective epi-drug monotherapy for breast cancer. Combining epigenetic drugs with conventional therapies has yielded positive outcomes and may be a promising strategy for breast cancer therapy. DNA methyltransferase inhibitors, such as azacitidine, and histone deacetylase inhibitors, such as vorinostat, have been used in combination with chemotherapy to treat breast cancer. miRNA regulators, such as miRNA mimics and antagomiRs, can alter the expression of specific genes involved in cancer development. miRNA mimics, such as miR-34, have been used to inhibit tumor growth, while antagomiRs, such as anti-miR-10b, have been used to inhibit metastasis. The development of epi-drugs that target specific epigenetic changes may lead to more effective monotherapy options in the future.

Overexpressed RBPMS-AS1 increased cell radiosensitivity by sponging miR-19a-3p in lung cancer cell lines (A549 and SK-MES-1) via regulating PTEN/AKT axis

PURPOSE

This paper intended to study RBPMS-AS1 in lung cancer (LC) radiosensitivity.

MATERIALS AND METHODS

LC cells were transfected with RBPMS-AS1 overexpression plasmid and miR-19a-3p mimic and treated with radiation. PTEN, AKT, p-AKT, RBPMS-AS1, and miR-19a-3p expressions were detected via Western blot and qRT-PCR. The localization of RBPMS-AS1 in cells was determined through fluorescence in situ hybridization assay. The targeting relationships of RBPMS-AS1 and miR-19a-3p/miR-19a-3p and PTEN were determined through RIP and dual luciferase reporter analysis. Cell survival, viability, and apoptosis were assessed through colony formation, CCK-8, and flow-cytometry assays.

RESULTS

RBPMS-AS1 was downregulated in LC and mainly distributed in cytoplasm. RBPMS-AS1 targeted miR-19a-3p in LC cells. Radiation suppressed LC cell survival, viability, and induced apoptosis, as overexpressed RBPMS-AS1 performed the similar effects and enhanced those effects induced by radiation. MiR-19a-3p mimic reversed the effect of overexpressed RBPMS-AS1 on enhancing radiation-induced LC cell apoptosis. MiR-19a-3p targeted PTEN and miR-19a-3p mimic reversed the effect of overexpressed RBPMS-AS1 on PTEN and phosphorylation of AKT in LC cells.

CONCLUSION

Overexpressed RBPMS-AS1 sponged miR-19a-3p to increase cell radiosensitivity in LC via regulating PTEN/AKT axis.

Potential Role of Circulating miRNAs for Breast Cancer Management in the Neoadjuvant Setting: A Road to Pave

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.

miRNAs as therapeutic predictors and prognostic biomarkers of neoadjuvant chemotherapy in breast cancer: a systematic review and meta-analysis

PURPOSE

Accumulating evidence has shown that microRNAs (miRNAs) are promising biomarkers of neoadjuvant chemotherapy (NAC) response in breast cancer (BC). However, their predictive roles remain controversial. Thus, this systematic review and meta-analysis aimed to describe the role of miRNA expression in NAC response and prognosis in BC to increase statistical power and improve translation.

METHODS

A systematic review of electronic databases for relevant studies was conducted following PRISMA guidelines. Data were extracted, collated, and combined by odds ratio (OR) and hazard ratio (HR) with 95% confidence intervals (CIs) to estimate the strength of the associations.

RESULTS

Of the 560 articles screened, 59 studies were included in our systematic review, and 5 studies were included in the subsequent meta-analysis. Sixty of 123 miRNAs were found to be related with NAC response and an elevated baseline miR-7 level in tissues was associated with a higher pathological complete response rate (OR 5.63; 95% CI 2.15-14.79; P = 0.0004). The prognostic value of 39 miRNAs was also studied. Of them, 26 miRNAs were found to be associated with survival. Pooled HRs indicated that patients with increased levels of serum miR-21 from baseline to the end of the second NAC cycle and from baseline to the end of NAC had a worse disease-free survival than those with decreased levels.

CONCLUSION

Our results highlight that a large number of miRNAs have possible associations with NAC response and prognosis in BC patients. Further well-designed studies are needed to elucidate the molecular mechanisms underlying these associations.

The Role of miRNAs in the Resistance of Anthracyclines in Breast Cancer: A Systematic Review

Breast cancer has been reported as the most common cancer in women globally, with 2.26 million new cases in 2020. While anthracyclines are the first-line drug for breast cancer, they cause a variety of adverse reactions and drug resistance, especially for triple-negative breast cancer, which can lead to poor prognosis, high relapse, and mortality rate. MicroRNAs (miRNAs) have been shown to be important in the initiation, development and metastasis of malignancies and their abnormal transcription levels may influence the efficacy of anthracyclines by participating in the pathologic mechanisms of breast cancer. Therefore, it is essential to understand the exact role of miRNAs in the treatment of breast cancer with anthracyclines. In this review, we outline the mechanisms and signaling pathways involved in miRNAs in the treatment of breast cancer using anthracyclines. The role of miRNA in the diagnosis, prognosis and treatment of breast cancer patients is discussed, along with the involvement of miRNAs in chemotherapy for breast cancer.

miR‑382‑3p downregulation contributes to the carcinogenesis of lung adenocarcinoma by promoting AKT SUMOylation and phosphorylation

Lung adenocarcinoma (LA), the primary histological type of non-small cell lung cancer, is still incurable; its diagnosis and treatment remain a major clinical challenge. A previous study by our group examined the microRNA (miRNA/miR) expression profile in the extracellular vesicles from patients with LA and healthy controls and indicated that miR-382-3p levels were reduced in patients with LA. However, the precise roles of miR-382-3p in LA have so far remained elusive. In the present study, the miR-382-3p levels in tumor and adjacent non-tumor control samples from 78 patients with LA were examined and it was identified that miR-382-3p expression was reduced in LA tumor samples compared with that in adjacent non-tumor control tissues (P=0.022). Furthermore, miR-382-3p overexpression inhibited LA growth in a xenograft mouse model. Prediction results indicated that miR-382-3p may regulate protein ubiquitination and SUMOylation. Small ubiquitin-like modifier (SUMO)1 activating enzyme subunit 1 (SAE1), one of the key components of the SUMO-activating complex, was identified as a direct target of miR-382-3p via dual-luciferase and immunoblotting assays. In patients with LA, miR-382-3p expression was negatively correlated with SAE1 protein levels (r=-0.39, P<0.05) and higher SAE1 expression contributed to poor prognosis (P<0.01). Using immunoprecipitation, it was identified that miR-382-3p reduction-induced SAE1 overexpression upregulated AKT SUMOylation, which further promoted AKT phosphorylation and activated the AKT signaling pathway. miR-382-3p inhibition promoted proliferation and inhibited apoptosis in LA cell lines, which was restored by SAE1 knockdown. In conclusion, the present study revealed that downregulation of miR-382-3p contributed to the carcinogenesis of LA via upregulation of SAE1 and promotion of AKT SUMOylation, providing a candidate target for LA treatment.

Circulating miRNAs in Breast Cancer Diagnosis and Prognosis

Great improvement has been made in the diagnosis and therapy of breast cancer patients. However, the identification of biomarkers for early diagnosis, prognosis, therapy assessment and monitoring, including drug resistance and the early detection of micro-metastases, is still lacking. Recently, circulating microRNAs (miRNAs), circulating freely in the blood stream or entrapped in extracellular vesicles (EVs), have been shown to have a potential diagnostic, prognostic or predictive power. In this review, recent findings are summarized, both at a preclinical and clinical level, related to miRNA applicability in the context of breast cancer. Different aspects, including clinical and technical challenges, are discussed, describing the potentialities of miRNA use in breast cancer. Even though more methodological standardized studies conducted in larger and selected patient cohorts are needed to support the effective clinical utility of miRNA as biomarkers, they could represent novel and accessible tools to be transferred into clinical practice.

The potential role of miR-1290 in cancer progression, diagnosis, prognosis, and treatment: An oncomiR or onco-suppressor microRNA?

Cancer is one of the leading causes of death in humans because of the lack of early diagnosis, distant metastases, and the resistance to adjuvant therapies, including chemotherapy and radiotherapy. In addition to playing an essential role in tumor progression and development, microRNAs (miRNAs) can be used as a robust biomarker in the early detection of cancer. MiR-1290 was discovered for the first time in human embryonic stem cells, and under typical physiological situations, plays an essential role in neuronal differentiation and neural stem cell proliferation. Its coding sequence is located at the 1p36.13 regions in the first intron of the aldehyde dehydrogenase 4 gene member A1. miR-1290 is out of control in many cancers such as breast cancer, colorectal cancer, esophageal squamous cell carcinoma, gastric cancer, lung cancer, pancreatic cancer, and plays a vital role in their development. Therefore, it is suggested that miR-1290 can be considered as a potential diagnostic and therapeutic target in many cancers. In addition to the importance of miR-1290 in the noninvasive diagnosis of various cancers, this systematic review study discussed the role of miR-1290 in altering the expression of different genes involved in cancer development and chemo-radiation resistance. Moreover, it considered the regulatory effect of natural products on miR-1290 expression and the interaction of lncRNAs by miR-1290.

Circulating microRNAs as indicators in the prediction of neoadjuvant chemotherapy response in luminal B breast cancer

PURPOSE

Circulating microRNAs (miRNAs) have been indicated as predictive biomarker for the response to neoadjuvant chemotherapy (NAC) and the prognosis of breast cancer (BC); however, to date the conclusions have been controversial. The biological characteristics of BC were affected by molecular subtypes. Hence, we aimed to investigate the predictive effect of miRNAs on NAC response in luminal B BC patients.

METHODS

Thirty-seven luminal B BC patient under NAC were prospectively enrolled in this study. Based on their clinical, pathological, and comprehensive response, the patients were defined as responder or non-responders, respectively. Circulating miRNAs were isolated from blood samples before and at the middle of NAC, and candidate miRNAs (miR-34a-5p, miR-125b-5p, miR-210, miR-222, miR-375, miR-718, miR-4516, and let-7g) were analyzed by quantitative real-time polymerase chain reaction (PCR). In addition, the association between miRNAs and disease-free survival (DFS) was examined.

RESULTS

miR-718, miR-4516, miR-210, and miR-125b-5p were found to be specific miRNAs associated with chemo-sensitivity of luminal B HER2 negative patients (n = 24). In the luminal B HER2 positive cohort (n = 13), dynamics of miR-222 and let-7g correlated with pathological response. Treatment-induced increase in miR-34a-5p in the responders except who reached pathologic complete response (pCR) was consistently identified across all luminal B patients and its two subgroups. Finally, after adjustments for Neo-Bioscore, patients with increased levels of miR-125b-5p during NAC had a worse DFS than those with decreased levels (HR = 5.86, 95% CI = 1.39-24.62, p = 0.016).

CONCLUSION

Specific circulating miRNAs were identified as predictive markers for NAC response and prognosis in luminal B BC. The underlying mechanism needs further studies.

Differences in plasma microRNA content impair microRNA-based signature for breast cancer diagnosis in cohorts recruited from heterogeneous environmental sites

Circulating microRNAs are non-invasive biomarkers that can be used for breast cancer diagnosis. However, differences in cancer tissue microRNA expression are observed in populations with different genetic/environmental backgrounds. This work aims at checking if a previously identified diagnostic circulating microRNA signature is efficient in other genetic and environmental contexts, and if a universal circulating signature might be possible. Two populations are used: women recruited in Belgium and Rwanda. Breast cancer patients and healthy controls were recruited in both populations (Belgium: 143 primary breast cancers and 136 healthy controls; Rwanda: 82 primary breast cancers and 73 healthy controls; Ntot = 434), and cohorts with matched age and cancer subtypes were compared. Plasmatic microRNA profiling was performed by RT-qPCR. Random Forest was used to (1) evaluate the performances of the previously described breast cancer diagnostic tool identified in Belgian-recruited cohorts on Rwandan-recruited cohorts and vice versa; (2) define new diagnostic signatures common to both recruitment sites; (3) define new diagnostic signatures efficient in the Rwandan population. None of the circulating microRNA signatures identified is accurate enough to be used as a diagnostic test in both populations. However, accurate circulating microRNA signatures can be found for each specific population, when taken separately.

MicroRNAs Regulating Tumor and Immune Cell Interactions in the Prediction of Relapse in Early Stage Breast Cancer

MicroRNAs (miRNAs) are involved in the regulation of immune response and hold an important role in tumor immune escape. We investigated the differential expression of the immunomodulatory miR-10b, miR-19a, miR-20a, miR-126, and miR-155 in the plasma of healthy women and patients with early stage breast cancer and interrogated their role in the prediction of patients’ relapse. Blood samples were obtained from healthy women (n = 20) and patients with early stage breast cancer (n = 140) before adjuvant chemotherapy. Plasma miRNA expression levels were assessed by RT-qPCR. Relapse predicting models were developed using binary logistic regression and receiver operating curves (ROC) were constructed to determine miRNA sensitivity and specificity. Only miR-155 expression was lower in patients compared with healthy women (p = 0.023), whereas miR-155 and miR-10b were lower in patients who relapsed compared with healthy women (p = 0.039 and p = 0.002, respectively). MiR-155 expression combined with axillary lymph node infiltration and tumor grade demonstrated increased capability in distinguishing relapsed from non-relapsed patients [(area under the curve, (AUC = 0.861; p < 0.001)]. Combined miR-19a and miR-20a expression had the highest performance in discriminating patients with early relapse (AUC = 0.816; p < 0.001). Finally, miR-10b in combination with lymph node status and grade had the highest accuracy to discriminate patients with late relapse (AUC = 0.971; p < 0.001). The robustness of the relapse predicting models was further confirmed in a 10-fold cross validation. Deregulation of circulating miRNAs involved in tumor-immune interactions may predict relapse in early stage breast cancer. Their successful clinical integration could potentially address the significance challenge of treatment escalation or de-escalation according to the risk of recurrence.

Identification of miR‑25‑3p as a tumor biomarker: Regulation of cellular functions via TOB1 in breast cancer

Breast cancer is the most common cancer in women and is one of the three most common malignancies worldwide. Serum microRNAs (miRNAs/miRs) are ideal biomarkers for tumor diagnosis and prognosis due to their specific biological characteristics. In several different types of cancer, miRNAs are associated with cell migration and invasion. In the present study, miR‑25‑3p expression levels were detected in tissue and serum samples derived from patients with breast cancer, and the diagnostic and prognostic value of miR‑25‑3p in breast cancer was evaluated. Cellular function assays were performed to evaluate the role of miR‑25‑3p in breast cancer. Moreover, dual‑luciferase reporter assays and western blotting were performed to investigate the target of miR‑25‑3p. miR‑25‑3p expression was upregulated in breast cancer tissue and serum samples compared with normal breast tissue and serum samples. Patients with breast cancer with high serum miR‑25‑3p levels were more likely to have lymph node metastasis compared with those with low serum miR‑25‑3p levels. The area under the curve for miR‑25‑3p in the diagnosis of breast cancer was 0.748, with 57.1% sensitivity and 95.0% specificity. Moreover, the Kaplan‑Meier survival curves demonstrated that patients with breast cancer with a low expression of serum miR‑25‑3p had a higher overall survival rate compared with patients with a high serum miR‑25‑3p expression. miR‑25‑3p knockdown suppressed breast cancer cell proliferation and invasion, and transducer of ERBB2, 1 (TOB1) was identified as a potential target gene regulated by miR‑25‑3p. Therefore, the present study suggested that miR‑25‑3p regulated cellular functions via TOB1 in breast cancer; therefore, miR‑25‑3p may serve as a breast cancer biomarker.

miR-19a/b promote EMT and proliferation in glioma cells via SEPT7-AKT-NF-κB pathway

miR-19a/b belong to the miR-17-92 family. We have demonstrated previously that miR-19a/b are overexpressed in glioma and glioma cell lines. However, the role of miR-19a/b in glioma remains unclear. In the present study, we aim to identify the biological function and molecular mechanism of miR-19a/b in glioma cell proliferation and epithelial-mesenchymal transition (EMT). Knocking down miR-19a/b in LN308 glioblastoma (GBM) cells with higher expression of miR-19a/b inhibits cell proliferation and invasion, induces apoptosis, and suppresses EMT by downregulating the expression of Akt, phosphorylated p-Akt, nuclear factor κB (NF-κB), Snail, N-cadherin, and Vimentin and upregulating E-cadherin in vitro and in vivo. Enhanced proliferation and EMT are also observed when miR-19a/b are transfected into SNB19 GBM cells, with lowered expression of miR-19a/b. miR-19a is more effective than miR-19b in the regulation of biological behavior of glioma cells. miR-19a/b modulate molecular events for the promotion of EMT via the Akt-NF-κB pathway. SEPT7 has been confirmed as the target gene of miR-19a/b. The effect of miR-19a/b on proliferation and EMT of glioma cells and the Akt-NF-κB pathway could be reversed by transfection with SEPT7. Our study strongly suggests that miR-19a/b play a significant role in glioma progression and EMT through regulating target gene-SEPT7 and the SEPT7-Akt-NF-κB pathway.

miR-205 in Breast Cancer: State of the Art

Despite its controversial roles in different cancer types, miR-205 has been mainly described as an oncosuppressive microRNA (miRNA), with some contrasting results, in breast cancer. The role of miR-205 in the occurrence or progression of breast cancer has been extensively studied since the first evidence of its aberrant expression in tumor tissues versus normal counterparts. To date, it is known that the expression of miR-205 in the different subtypes of breast cancer is decreasing from the less aggressive subtype, estrogen receptor/progesterone receptor positive breast cancer, to the more aggressive, triple negative breast cancer, influencing metastasis capability, response to therapy and patient survival. In this review, we summarize the most important discoveries that have highlighted the functional role of this miRNA in breast cancer initiation and progression, in stemness maintenance, in the tumor microenvironment, its potential role as a biomarker and its relevance in normal breast physiology—the still open questions. Finally, emerging evidence reveals the role of some lncRNAs in breast cancer progression as sponges of miR-205. Here, we also reviewed the studies in this field.

Targeting MALAT1 induces DNA damage and sensitize non-small cell lung cancer cells to cisplatin by repressing BRCA1

PURPOSE

Metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) is a long non-coding RNA which has been identified to be involved in alternative non-homologous end joining (A-NHEJ) pathways by binding with PARP1 and LIG3 in myeloma cells. This study aims to explore the roles of MALAT1 in DNA repair processes in non-small cell lung cancer (NSCLC).

METHODS

The interactions between MALAT1 and proteins were identified by co-immunoprecipitation and RNA pulldown. The interactions between MALAT1 and microRNAs (miRNA) were predicted by bioinformatics tools and confirmed by luciferase assay and RNA pulldown. The DNA damages were quantified by comet assay. The cell viability was examined by MTT assay and the cell apoptosis was determined by flow cytometry.

RESULTS

MALAT1 is identified to be involved in A-NHEJ pathway in NSCLC cells. However, in LIG3-null cells where A-NHEJ pathway is inactivated, targeting MALAT1 still increases DNA damages, suggesting that MALAT1 participates in other DNA repair pathways. Subsequently, MALAT1 is identified to bind with miR-146a and miR-216b, which directly target the 3'UTR of BRCA1. MALAT1 is confirmed to functions as a competing endogenous RNA (ceRNA) absorbing miR-146a and miR-216b, upregulating BRCA1 expression and protecting Homologous Recombination (HR) pathway in NSCLC cells. Finally, overexpression MALAT1 protects NSCLC cells from the cytotoxic effect of cisplatin. While, targeting MALAT1 in NSCLC cells induces DNA damages by repressing HR pathway and sensitizes NSCLC cells to cisplatin which had the potential for NSCLC treatment.

CONCLUSION

MALAT1 is involved in HR pathway by protecting BRCA1 and targeting MALAT1 induces DNA damages in NSCLC.

Circulating MicroRNAs as Prognostic and Therapeutic Biomarkers in Breast Cancer Molecular Subtypes

Breast cancer (BC) is a common and heterogeneous disease, of which six molecular subtypes, characterized by different biological features and clinical outcomes, were described. The identification of additional biomarkers able to further connote and distinguish the different BC subtypes is essential to improve the diagnostic, prognostic and therapeutic strategies in BC patients. MicroRNAs (miRNAs) are short non-coding RNA involved in several physiological and pathological processes, including cancer development and progression. In particular, circulating miRNAs, which can be found in an adequately stable structure in serum/plasma of cancer patients, are emerging as very promising non-invasive biomarkers. Several studies have analyzed the potential role of circulating miRNAs as prognostic and therapeutic markers in BC. In the present review we describe circulating miRNAs, identified as putative biomarker in BC, with special reference to different BC molecular subtypes.

Prospective Assessment of Systemic MicroRNAs as Markers of Response to Neoadjuvant Chemotherapy in Breast Cancer

Neoadjuvant chemotherapy (NACT) is used in locally advanced breast cancer to reduce tumour burden prior to surgical resection. However, only a subset of NACT treated patients will respond to treatment or achieve a pathologic complete response (pCR). This multicenter, prospective study (CTRIAL-IE (ICORG) 10-11 study) evaluated circulating microRNA as novel non-invasive prognostic biomarkers of NACT response in breast cancer. Selected circulating microRNAs (Let-7a, miR-21, miR-145, miR-155, miR-195) were quantified from patients undergoing standard of care NACT treatment (n = 114) from whole blood at collected at diagnosis, and the association with NACT response and clinicopathological features evaluated. NACT responders had significantly lower levels of miR-21 (p = 0.036) and miR-195 (p = 0.017), compared to non-responders. Evaluating all breast cancer cases miR-21 was found to be an independent predictor of response (OR 0.538, 95% CI 0.308–0.943, p < 0.05). Luminal cancer NACT responders were found to have significantly decreased levels of miR-145 (p = 0.033) and miR-21 (p = 0.048), compared to non-responders. This study demonstrates the prognostic ability of miR-21, miR-195 and miR-145 as circulating biomarkers stratifying breast cancer patients by NACT response, identifying patients that will derive the maximum benefit from chemotherapy.

Effects of CORO2A on Cell Migration and Proliferation and Its Potential Regulatory Network in Breast Cancer

Coronin 2A (CORO2A) is a novel component of the N-CoR (nuclear receptor co-repressor) complex. Abnormal CORO2A expression is associated with carcinogenesis. We used databases from the Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO), and analyzed CORO2A expression and gene regulation networks in breast cancer. Expression was analyzed using GEO and TCGA database and further validated in breast cancer samples collected in our clinic. The prognostic value of CORO2A was explored by using the Kaplan–Meier survival analysis and Cox proportional hazards regression analysis. LinkedOmics was used to identify coexpressed genes associated with CORO2A. After analyzing the intersection of coexpressed genes correlated with CORO2A and differentially expressed genes after CORO2A silencing, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses of the intersecting genes were conducted by using FunRich software. Transwell assays were performed in breast cancer cells to determine the effect of CORO2A on cell migration. MTS, colony formation, and cell cycle distribution assays were performed in breast cancer cells to determine the effect of CORO2A on cell proliferation. Gene enrichment analysis was employed to explore the target networks of transcription factors and miRNAs. We found that CORO2A was upregulated and that the elevated expression of CORO2A was associated with poor overall survival (OS) and relapse-free survival (RFS) in TNBC patients. Further bioinformatics analysis of public sequencing data and our own RNA-Seq data revealed that CORO2A was probably involved in the epithelial-to-mesenchymal transition process and might have a significant effect on the migration of breast cancer cells, which might be mediated via pathways involving several miRNAs and MYC transcription factors. Functionally, the knockdown of CORO2A inhibited cell migration, decreased viability, and colony formation and induced cell cycle arrest in the G0/G1 phase in breast cancer cells. These results demonstrate that bioinformatics-based analysis efficiently reveals information about CORO2A expression and its potential regulatory networks in breast cancer, laying a foundation for further mechanistic research on the role of CORO2A in carcinogenesis. Moreover, CORO2A promotes the migration and proliferation of breast cancer cells and may have an important function in breast cancer progression. CORO2A is a potential prognostic predictor for TNBC patients. Targeting CORO2A may provide promising therapy strategies for breast cancer treatment.

Circulating microRNA as biomarkers of canine mammary carcinoma in dogs

Background

Differentiating benign from canine malignant mammary tumors requires invasive surgical biopsy. Circulating microRNAs (miRNA) may represent promising minimally invasive cancer biomarkers in people and animals.

Objectives

To evaluate the serum mRNA profile between dogs with and without mammary carcinoma, and to determine if any of these markers have prognostic significance.

Animals

Ten healthy client‐owned female dogs (5 intact, 5 spayed) and 10 dogs with histologically confirmed mammary carcinoma were included; 9 were client‐owned, whereas 1 was a research colony dog.

Methods

Retrospective study. Serum miRNA was evaluated by RNA deep‐sequencing (RNAseq) and digital droplet PCR (dPCR).Expression of candidate biomarkers miR‐18a, miR‐19b, miR‐29b, miR‐34c, miR‐122, miR‐125a, and miR‐181a was compared with clinical characteristics, including grade, metastasis, and survival.

Results

452 unique serum miRNAs were detected by RNAseq. Sixty‐five individual miRNAs were differentially expressed (>±1.5‐fold) and statistically significant between groups. Serum miR‐19b (P = .003) and miR‐125a (P < .001) were significantly higher in the mammary carcinoma group by dPCR. Both had high accuracy based on receiver operator characteristic area under the curve (0.930 for miR‐125a; 0.880 for miR‐19b). Circulating miR‐18a by RNAseq was significantly higher in mammary carcinoma dogs with histologic evidence of lymphatic invasion (P = 0.03). There was no significant association with any miRNA and survival or inflammatory status.

Conclusions and Clinical Importance

Circulating miRNAs are differentially expressed in dogs with mammary carcinoma. Serum miR‐19b and miR‐18a represent candidate biomarkers for diagnosis and prognosis, respectively.

MiR-205 Dysregulations in Breast Cancer: The Complexity and Opportunities

MicroRNAs (miRNAs) are endogenous non-coding small RNAs that downregulate target gene expression by imperfect base-pairing with the 3' untranslated regions (3'UTRs) of target gene mRNAs. MiRNAs play important roles in regulating cancer cell proliferation, stemness maintenance, tumorigenesis, cancer metastasis, and cancer therapeutic resistance. While studies have shown that dysregulation of miRNA-205-5p (miR-205) expression is controversial in different types of human cancers, it is generally observed that miR-205-5p expression level is downregulated in breast cancer and that miR-205-5p exhibits a tumor suppressive function in breast cancer. This review focuses on the role of miR-205-5p dysregulation in different subtypes of breast cancer, with discussions on the effects of miR-205-5p on breast cancer cell proliferation, epithelial-mesenchymal transition (EMT), metastasis, stemness and therapy-resistance, as well as genetic and epigenetic mechanisms that regulate miR-205-5p expression in breast cancer. In addition, the potential diagnostic and therapeutic value of miR-205-5p in breast cancer is also discussed. A comprehensive list of validated miR-205-5p direct targets is presented. It is concluded that miR-205-5p is an important tumor suppressive miRNA capable of inhibiting the growth and metastasis of human breast cancer, especially triple negative breast cancer. MiR-205-5p might be both a potential diagnostic biomarker and a therapeutic target for metastatic breast cancer.

Circulating miRNAs as Diagnostic and Prognostic Biomarkers in Common Solid Tumors: Focus on Lung, Breast, Prostate Cancers, and Osteosarcoma

An early cancer diagnosis is essential to treat and manage patients, but it is difficult to achieve this goal due to the still too low specificity and sensitivity of classical methods (imaging, actual biomarkers), together with the high invasiveness of tissue biopsies. The discovery of novel, reliable, and easily collectable cancer markers is a topic of interest, with human biofluids, especially blood, as important sources of minimal invasive biomarkers such as circulating microRNAs (miRNAs), the most promising. MiRNAs are small non-coding RNAs and known epigenetic modulators of gene expression, with specific roles in cancer development/progression, which are next to be implemented in the clinical routine as biomarkers for early diagnosis and the efficient monitoring of tumor progression and treatment response. Unfortunately, several issues regarding their validation process are still to be resolved. In this review, updated findings specifically focused on the clinical relevance of circulating miRNAs as prognostic and diagnostic biomarkers for the most prevalent cancer types (breast, lung, and prostate cancers in adults, and osteosarcoma in children) are described. In addition, deep analysis of pre-analytical, analytical, and post-analytical issues still affecting the circulation of miRNAs' validation process and routine implementation is included.

The NF-κB-modulated miR-19a-3p enhances malignancy of human ovarian cancer cells through inhibition of IGFBP-3 expression

Ovarian cancer is the most lethal gynecologic malignancy due to the lack of symptoms until advanced stages, and new diagnosis and treatment strategy is in urgent need. In this study, we found higher expression of miR-19a-3p in ovarian cancer tissues compared with that in the adjacent normal tissues. By chromatin immunoprecipitation (ChIP) and electrophoretic mobility shift assay (EMSA) analysis, we showed that nuclear factor-kappaB (NF-κB) binds to the promoter of miR-19a-3p, leading to reduced expression in ovarian cancer cells. Further study indicated that miR-19a-3p inhibits the expression of insulin-like growth factor binding protein-3 (IGFBP-3), resulting in enhanced growth and migration of ovarian cancer cells in vitro and tumor growth in vivo. These results showed that miR-19a-3p enhances the oncogenesis of ovarian cancer through inhibition of IGFBP-3 expression, and which can be inhibited by NF-κB, suggesting an NF-κB/miR-19a-3p/IGFBP-3 pathway in the oncogenesis of ovarian cancer, which expands our understanding of ovarian cancer and they may contribute to the development of new diagnosis and treatment of ovarian cancer.

Serum microRNA-21 predicted treatment outcome and survival in HER2-positive breast cancer patients receiving neoadjuvant chemotherapy combined with trastuzumab

PURPOSE

The purpose of this study was to evaluate the expression of ser-miRNAs at different periods during treatment and analyze their relationship with therapeutic response and prognosis in HER2-positive breast cancer patients receiving neoadjuvant chemotherapy combined with trastuzumab (NCCT).

METHODS

Venous blood was drawn from patients at different periods during NCCT. The expression of ser-miRNAs was assessed by qRT-PCR and their relation to treatment response and survival was analyzed.

RESULTS

The results showed the expression of miR-10b, -21, -34a, -125b, -145, -155, and -373 in patients before the start of treatment was significantly higher, ser-miR-210 was lower, and ser-miR-122 was comparable to the levels in healthy controls. Changes in ser-miR-21 levels during NCCT were significantly correlated to clinical response and survival and, however, were not associated with pathology response. The expression levels of ser-miR-21 were decreased from the start of NCCT to the end of the second cycle and from the start to the end of NCCT in clinical responders; however, there was no significant difference in non-responders. The patients with decreased ser-miR-21 expression from the start to the end of the second cycle and from the start to the end of NCCT had better overall survival (OS) and disease-free survival (DFS) than those with elevated ser-miR-21 expression.

CONCLUSION

These results showed that changes in ser-miR-21 levels were significantly related to NCCT clinical response and prognosis. Ser-miR-21 may serve as a non-invasive biomarker to predict NCCT response in HER2-positive breast cancer.

miR-1301/TRIAP1 Axis Participates in Epirubicin-Mediated Anti-Proliferation and Pro-Apoptosis in Osteosarcoma

PURPOSE

Epirubicin is one of the most effective drugs against osteosarcoma. miR-1301 is involved in the occurrence and development of osteosarcoma. Whether miR-1301 is responsible for the chemosensitivity of osteosarcoma cells to epirubicin remains largely unknown.

MATERIALS AND METHODS

U2OS and SAOS-2 cells were treated with various concentrations of epirubicin. Flow cytometry was employed to evaluate cell apoptotic rate. Cell proliferation was measured by Cell Counting Kit-8 assay. Western blot and quantitative real-time polymerase chain reaction were utilized to detect the expressions of B-cell lymphoma-2 (Bcl-2), Bcl-2 assaciated X protein (Bax), cleaved-caspase-3, cleaved-poly (ADP-ribose) polymerases (PARP1), TP53-regulated inhibitor of apoptosis 1 (TRIAP1), and microRNA-1301 (miR-1301). The relationship between miR-1301 and TRIAP1 was determined by luciferase reporter assay.

RESULTS

Epirubicin inhibited proliferation in a dose-dependent manner, induced apoptosis, decreased the expression of Bcl-2, and increased the expressions of Bax, cleaved-caspase-3, and cleaved-PARP1 in osteosarcoma cells. miR-1301 was downregulated in U2OS and SAOS-2 cells. Importantly, epirubicin significantly increased the levels of miR-1301. Overexpression of miR-1301 suppressed proliferation and promoted apoptosis. Interestingly, those effects were enhanced by epirubicin. In contrast, miR-1301 depletion attenuated the epirubicin-mediated anti-osteosarcoma effect. miR-1301 negatively regulated the expression of TRIAP1 in U2OS and SAOS-2 cells. Furthermore, epirubicin inhibited the mRNA and protein levels of TRIAP1 by upregulating miR-1301 levels. Epirubicin suppressed cell proliferation by downregulating TRIAP1.

CONCLUSION

miR-1301 was implicated in the chemosensitivity of osteosarcoma to epirubicin by modulating TRIAP1.

Clinical utility of circulating non-coding RNAs - an update

Over the past decade, the amount of research and the number of publications on associations between circulating small and long non-coding RNAs (ncRNAs) and cancer have grown exponentially. Particular focus has been placed on the development of diagnostic and prognostic biomarkers to enable efficient patient management - from early detection of cancer to monitoring for disease recurrence or progression after treatment. Owing to their high abundance and stability, circulating ncRNAs have potential utility as non-invasive, blood-based biomarkers that can provide information on tumour biology and the effects of treatments, such as targeted therapies and immunotherapies. Increasing evidence highlights the roles of ncRNAs in cell-to-cell communication, with a number of ncRNAs having the capacity to regulate gene expression outside of the cell of origin through extracellular vesicle-mediated transfer to recipient cells, with implications for cancer progression and therapy resistance. Moreover, 'foreign' microRNAs (miRNAs) encoded by non-human genomes (so-called xeno-miRNAs), such as viral miRNAs, have been shown to be present in human body fluids and can be used as biomarkers. Herein, we review the latest developments in the use of circulating ncRNAs as diagnostic and prognostic biomarkers and discuss their roles in cell-to-cell communication in the context of cancer. We provide a compendium of miRNAs and long ncRNAs that have been reported in the literature to be present in human body fluids and that have the potential to be used as diagnostic and prognostic cancer biomarkers.

A new insight on serum microRNA expression as novel biomarkers in breast cancer patients

Breast cancer (BC) is one of the widespread lethal diseases affecting a large number of women worldwide. As such, employing and identifying significant markers for detecting BC in different stages can assist in better diagnosis and management of the disease. Several diverse markers have been introduced for diagnosis, but their limitations, including low specificity and sensitivity, reduce their application. microRNAs (miRNAs), as short noncoding RNAs, have been shown to significantly influence gene expression in different disease pathologies, especially BC. Clearly, among different samples used for detecting miRNA expressions, circulating miRNAs present as promising and useful biomarkers. Among different body fluid samples, serum serves as one of the most reliable samples, thanks to its high stability under various severe conditions and some unique features. Extensive research has suggested that BC-related miRNAs can remain stable in the serum. The objective of this review is to describe different samples used for detecting miRNAs in BC subjects with emphasis on serum miRNAs. So, this study highlights serum miRNAs with the potential of acting as biomarkers for different stages of BC. We reviewed the possible correlation between potential miRNAs and the risk of early breast cancer, metastatic breast cancer, response to chemotherapy, and relapse.

Plasma microRNAs Predict Chemoresistance in Patients With Metastatic Breast Cancer

Background: MicroRNAs contribute to chemotherapy response in different types of cancer. We hypothesized that plasma miRNAs are potentially associated with chemotherapy response in patients with metastatic breast cancer. Patients and Methods: Fourteen candidate microRNAs were chosen from the literature, and their plasma levels were measured by quantitative polymerase chain reaction (PCR). Forty metastatic breast cancer patients were chosen as the training groups. The potential significant microRNAs were validated in another 103 plasma samples. Results: In the training set, we identified 3 microRNAs (miR-200a, miR-210, and miR-451) as significantly dysregulated miRNAs between sensitive group (partial response (and stable disease) and resistant group (progressive disease). Then, in the validation set, miR-200a (area under the curve = 0.881, sensitivity = 94.1%, specificity = 76.7%) and miR-210 (area under the curve = 0.851, sensitivity = 88.2%, specificity = 72.1%) showed high diagnostic accuracy for distinguishing sensitive group from resistant group. Furthermore, the plasma level of miR-200a was significantly associated with the stage in surgery (P = .035), and the high level of miR-210 expression was associated with internal organ metastasis (liver, lung, and brain; P = .024). Conclusions: Plasma miR-200a and miR-210 could be effective biomarkers for the prediction of chemotherapy resistance in metastatic breast cancer patients.

Extracellular vesicle‑delivered miR‑505‑5p, as a diagnostic biomarker of early lung adenocarcinoma, inhibits cell apoptosis by targeting TP53AIP1

Lung adenocarcinoma (LA) is the most commonly occurring histological type of non‑small cell lung cancer. Diagnosis and treatment of LA remain a major clinical challenge. In the present study, to identify early LA biomarkers, extracellular vesicles (EVs) were separated from the plasma samples from 153 patients with LA and 75 healthy controls. microRNA (miRNA) expression profiling was performed at the screening stage (5 patients with LA vs. 5 controls), followed by verification at the validation stage (40 patients with LA vs. 20 controls) using reverse transcription‑quantitative polymerase chain reaction (RT‑qPCR). The four disordered miRNAs (miR‑505‑5p, miR‑486‑3p, miR‑486‑3p and miR‑382‑3p) identified in the plasma EVs were further evaluated at the testing stage (108 patients with LA vs. 50 controls) by RT‑qPCR. It was revealed that miR‑505‑5p was upregulated, whereas miR‑382‑3p was downregulated, in the EVs from patients with LA. Furthermore, miR‑505‑5p was also upregulated in tumor tissues, compared with adjacent non‑tumor control tissues. Subsequently, the direct targets of miR‑505‑5p were predicted using bioinformatics analyses, and verified by luciferase assay and immunoblotting. The present study determined that miR‑505‑5p functions as an oncogene, promoting lung cancer cell proliferation and inhibiting cancer cell apoptosis via the targeting of tumor protein P53‑regulated apoptosis‑inducing protein 1 (TP53AIP1). Finally, it was confirmed that miR‑505‑5p in plasma EVs could be delivered to lung cancer cells, inhibiting cell apoptosis and promoting cell proliferation by targeting TP53AIP1. In conclusion, the present study indicated that miRNA‑505‑5p functions as an oncogene that may be used as a novel biomarker for the diagnosis and treatment of LA.

Role of micro-RNAs in breast cancer surgery

BACKGROUND

The management of breast cancer has changed dramatically in the molecular era. Micro-RNAs can contribute to multiple facets of cancer surgery.

METHODS

This narrative review, based on years of research on the role of micro-RNAs, focused on the potential of these small, robust RNAs to influence all aspects of breast cancer surgery.

RESULTS

Micro-RNAs have a potential role as biomarkers in the diagnosis, prognosis and evaluation of response to therapy in breast cancer. They may also contribute to future therapeutic strategies.

CONCLUSION

The molecular era has changed understanding of cancer. Micro-RNAs have the potential for use in personalized cancer strategies.

Serum miR-4530 sensitizes breast cancer to neoadjuvant chemotherapy by suppressing RUNX2

Purpose

Neoadjuvant chemotherapy (NAC) plays a pivotal role in the treatment of locally advanced breast cancer (LABC); however, breast cancer is a heterogeneous disease, individual responses to chemotherapy are highly variable. Therefore, the purpose of the current research is to identify biomarkers that can predict the chemotherapeutic response.

Patients and methods

We recruited 78 patients with primary breast cancer who underwent taxane- and anthracycline-based NAC; these patients were divided into sensitive and resistant groups according to the Response Evaluation Criteria in Solid Tumors (RECIST) criteria. The microRNA microarray was conducted to explore differentially expressed miRNAs. Quantitative real-time polymerase chain reaction (qRT-PCR) further validated the relationship between miR-4530 and chemosensitivity in breast cancer patients.

Results

No significant differences were observed between the two groups regarding the clinicopathological characteristics. miR-4530 showed the most potential involving breast cancer chemosensitivity. Mechanically, RUNX2 was identified one of the direct targets of miR-4530 and responsible for breast cancer chemosensitivity.

Conclusion

Our results revealed that elevated serum miR-4530 levels may sensitize breast cancer to taxane- and anthracycline-based NAC by suppressing RUNX2; therefore, this miRNA has the potential to be a new biomarker for predicting breast cancer chemosensitivity.

Malignant canine mammary epithelial cells shed exosomes containing differentially expressed microRNA that regulate oncogenic networks

Background

Breast (mammary) cancers in human (BC) and canine (CMT) patients share clinical, pathological, and molecular similarities that suggest dogs may be a useful translational model. Many cancers, including BC, shed exosomes that contain microRNAs (miRs) into the microenvironment and circulation, and these may represent biomarkers of metastasis and tumor phenotype.

Methods

Three normal canine mammary epithelial cell (CMEC) cultures and 5 CMT cell lines were grown in serum-free media. Exosomes were isolated from culture media by ultracentrifugation then profiled by transmission electron microscopy, dynamic light scattering, and Western blot. Exosomal small RNA was deep-sequenced on an Illumina HiSeq2500 sequencer and validated by qRT-PCR. In silico bioinformatic analysis was carried out to determine microRNA gene and pathway targets.

Results

CMEC and CMT cell lines shed round, “cup-shaped” exosomes approximately 150–200 nm, and were immunopositive for exosomal marker CD9. Deep-sequencing averaged ~ 15 million reads/sample. Three hundred thirty-eight unique miRs were detected, with 145 having > ±1.5-fold difference between one or more CMT and CMEC samples. Gene ontology analysis revealed that the upregulated miRs in this exosomal population regulate a number of relevant oncogenic networks. Several miRNAs including miR-18a, miR-19a and miR-181a were predicted in silico to target the canine estrogen receptor (ESR1α).

Conclusions

CMEC and CMT cells shed exosomes in vitro that contain differentially expressed miRs. CMT exosomal RNA expresses a limited number of miRs that are up-regulated relative to CMEC, and these are predicted to target biologically relevant hormone receptors and oncogenic pathways. These results may inform future studies of circulating exosomes and the utility of miRs as biomarkers of breast cancer in women and dogs.

Electronic supplementary material

The online version of this article (10.1186/s12885-018-4750-6) contains supplementary material, which is available to authorized users.

miRNAs and lncRNAs as Predictive Biomarkers of Response to FOLFOX Therapy in Colorectal Cancer

Chemotherapy is one of the options for cancer treatment. FOLFOX is one of the widely used chemotherapeutic regimens used to treat primarily colorectal cancer and other cancers as well. However, the emergence of chemo-resistance clones during cancer treatment has become a critical challenge in the clinical setting. It is crucial to identify the potential biomarkers and therapeutics targets which could lead to an improvement in the success rate of the proposed therapies. Since non-coding RNAs have been known to be important players in the cellular system, the interest in their functional roles has intensified. Non-coding RNAs (ncRNAs) as regulators at the post-transcriptional level could be very promising to provide insights in overcoming chemo-resistance to FOLFOX. Hence, this mini review attempts to summarize the potential of ncRNAs correlating with chemo-sensitivity/resistance to FOLFOX.

The emerging role of miR-19 in glioma

Glioma has been regarded as the most common, highly proliferative and invasive brain tumour. Advances in research of miRNAs in glioma are toward further understanding of the pathogenesis of glioma. MiR‐19, a member of miR‐17~92 cluster, was reported to play an oncogenic role in tumourigenesis. Here we review the identified data about the effect of miR‐19 on proliferation, apoptosis, migration and invasion of glioma cells, the target genes regulated by miR‐19, and correlation of miR‐19 with the sensitivity of glioma cells to chemotherapy and radiotherapy. It is concluded that miR‐19 plays an important role in the pathogenesis of glioma and can be a potential target for gene therapy of glioma.

A six-microRNA panel in plasma was identified as a potential biomarker for lung adenocarcinoma diagnosis

Differently expressed microRNAs (miRNAs) in the plasma of lung adenocarcinoma (LA) patients might serve as biomarkers for LA detection. MiRNA expression profiling was performed using Exiqon panels followed by the verification (30 LA VS. 10 healthy controls (HCs)) with quantitative reverse transcription polymerase chain reaction (qRT-PCR) in the screening phase. Identified miRNAs were confirmed through training (42 LA VS. 32 HCs) and testing stages (66 LA VS. 62 HCs) by using qRT-PCR based absolute quantification methods. A total of six up-regulated plasma miRNAs (miR-19b-3p, miR-21-5p, miR-221-3p, miR-409-3p, miR-425-5p and miR-584-5p) were identified. The six-miRNA panel could discriminate LA patients from HCs with areas under the receiver operating characteristic curve of 0.72, 0.74 and 0.84 for the training, testing and the external validation stage (33 LA VS. 30 HCs), respectively. All the miRNAs identified except miR-584-5p were significantly up-regulated in LA tissues. MiR-19-3p, miR-21-5p, miR-409-3p and miR-425-5p showed high expression in arterial plasma with borderline significance. Additionally, miR-19-3p, miR-21-5p and miR-221-3p were significantly up-regulated in exosomes extracted from LA peripheral plasma samples. In conclusion, we identified a six-miRNA panel in peripheral plasma which might give assistance to the detection of LA at least for Asian population to a certain extent.

Robust expression of tumor suppressor miRNA's let-7 and miR-195 detected in plasma of Saudi female breast cancer patients

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.

Electronic supplementary material

The online version of this article (10.1186/s12885-017-3776-5) contains supplementary material, which is available to authorized users.

Circulating microRNAs in patients with hormone receptor-positive, metastatic breast cancer treated with dovitinib

BACKGROUND

Serial analysis of biomarkers in the circulation of patients undergoing treatment ("liquid biopsies") can provide new insights into drug effects. In particular the analysis of cell-free, circulating nucleic acids such as microRNAs (miRs) can reveal altered expression patterns indicative of mechanism of drug action, cancer growth, and tumor-stroma interactions.

RESULTS

Here we analyzed plasma miRs in patients with hormone receptor positive, metastatic breast cancer with prior disease progression during aromatase inhibitor therapy (n = 8) in a phase I/II trial with the multiple tyrosine kinase inhibitor dovitinib (TKI258). Plasma miR levels were measured by quantitative RT-qPCR before and after treatment with dovitinib. A candidate miR signature of drug response was established from a 379 miR screen for detectable plasma miRs as well as from the published literature. Changes in miR expression patterns and tumor sizes were compared. In this analysis we identified miR-21-5p, miR-100-5p, miR-125b-5p, miR-126-3p, miR-375 and miR-424-5p as potential indicators of a response to dovitinib. The altered expression patterns observed for the six circulating miRs separated patients with resistant disease from those with drug responsive disease. There was no relationship between adverse effects of dovitinib treatment and identifiable changes in miR patterns.

CONCLUSION

We conclude that changes in the expression patterns of circulating miRs can be indicators of drug responses that merit prospective studies for validation.

Micro-RNAs as Potential Predictors of Response to Breast Cancer Systemic Therapy: Future Clinical Implications

Despite advances in diagnosis and new treatments such as targeted therapies, breast cancer (BC) is still the most prevalent tumor in women worldwide and the leading cause of death. The principal obstacle for successful BC treatment is the acquired or de novo resistance of the tumors to the systemic therapy (chemotherapy, endocrine, and targeted therapies) that patients receive. In the era of personalized treatment, several studies have focused on the search for biomarkers capable of predicting the response to this therapy; microRNAs (miRNAs) stand out among these markers due to their broad spectrum or potential clinical applications. miRNAs are conserved small non-coding RNAs that act as negative regulators of gene expression playing an important role in several cellular processes, such as cell proliferation, autophagy, genomic stability, and apoptosis. We reviewed recent data that describe the role of miRNAs as potential predictors of response to systemic treatments in BC. Furthermore, upon analyzing the collected published information, we noticed that the overexpression of miR-155, miR-222, miR-125b, and miR-21 predicts the resistance to the most common systemic treatments; nonetheless, the function of these particular miRNAs must be carefully studied and further analyses are still necessary to increase knowledge about their role and future potential clinical uses in BC.

Serum miR-21 and miR-125b as markers predicting neoadjuvant chemotherapy response and prognosis in stage II/III breast cancer

The predictive value of serum miRNAs (ser-miRNA) for the response to neoadjuvant chemotherapy (NCT) and the prognosis of breast cancer patients were investigated in the current study. The study included 118 stage II/III breast cancer patients and 30 healthy adult women. Peripheral blood was drawn from participants before the start (baseline [BL]), at the end of the second cycle (first evaluation during NCT [FEN]), and at the end of NCT (second evaluation during NCT [SEN]). The expression of ser-miRNAs was examined by quantitative reverse-transcription polymerase chain reaction (qRT-PCR), and their association with chemotherapy response and prognosis was analyzed. MiR-19a, miR-21, miR-125b, miR-155, miR-205, and miR-373 were significantly up-regulated in the serum of breast cancer patients at BL, miR-451 was significantly down-regulated, and miR-122 was unchanged compared with the levels in healthy women. The expression of ser-miR-125b and the changes of ser-miR-21 expression during NCT were associated with chemotherapy response and disease-free survival (DFS). In chemotherapy responders, ser-miR-125b expression was lower than that of non-responders at BL, FEN, and SEN, and ser-miR-21 levels decreased from BL to FEN and from BL to SEN. Survival analysis showed that patients with lower ser-miR-125b expression at BL, FEN, and SEN had favorable DFS, and those with decreased ser-miR-21 expression from BL to FEN and from BL to SEN had better DFS. In conclusion, ser-miR-21 and ser-miR-125b were identified as novel, noninvasive predictive markers for NCT response and prognosis in breast cancer.

MicroRNAs mediate therapeutic and preventive effects of natural agents in breast cancer

MicroRNAs (miRNAs) are a set of non-coding small RNA molecules that play a critical role in regulation of protein coding genes in cells. MiRNAs have been extensively studied as novel biomarkers, therapeutic targets, and new drugs in various human diseases. Breast cancer is a one of the leading tumor types significantly affecting women health worldwide. Over the past decade, a number of natural agents, such as paclitaxel and curcumin, have been applied for treatment and prevention of breast cancer due to their relatively low toxicity. However, the mechanisms of action have not been completely understood. Investigation on miRNAs is able to potentially provide a novel insight into better understanding the anticancer activities of these natural products. Given that a single miRNA can target multiple genes, theoretically, those genes involved in a certain phenotype can be clustered with one or a few miRNAs. Therefore, pleiotropic activities of natural agents should be interpreted by interactions between selected miRNAs and their targets. In this review, we summarize the latest publications related to the alterations of miRNAs by two natural agents (paclitaxel and curcumin) that are currently used in intervention of breast cancer, and conclude that the mechanism involving the regulation of miRNA expression is one of the keys to understand pleiotropic activities of natural agents.

How interacting pathways are regulated by miRNAs in breast cancer subtypes

BACKGROUND

An important challenge in cancer biology is to understand the complex aspects of the disease. It is increasingly evident that genes are not isolated from each other and the comprehension of how different genes are related to each other could explain biological mechanisms causing diseases. Biological pathways are important tools to reveal gene interaction and reduce the large number of genes to be studied by partitioning it into smaller paths. Furthermore, recent scientific evidence has proven that a combination of pathways, instead than a single element of the pathway or a single pathway, could be responsible for pathological changes in a cell.

RESULTS

In this paper we develop a new method that can reveal miRNAs able to regulate, in a coordinated way, networks of gene pathways. We applied the method to subtypes of breast cancer. The basic idea is the identification of pathways significantly enriched with differentially expressed genes among the different breast cancer subtypes and normal tissue. Looking at the pairs of pathways that were found to be functionally related, we created a network of dependent pathways and we focused on identifying miRNAs that could act as miRNA drivers in a coordinated regulation process.

CONCLUSIONS

Our approach enables miRNAs identification that could have an important role in the development of breast cancer.

Abnormal serum microRNA profiles in tuberous sclerosis are normalized during treatment with everolimus: possible clinical implications

Background

Tuberous sclerosis (TSC) is a monogenic disease resulting from defects of the TSC1 or TSC2 genes, which encode the proteins forming hamartin-tuberin tumor suppressor complex, the mammalian target of rapamycin complex (mTOR). The mTOR pathway is constitutively activated in response to tuberin or hamartin defects. The mTOR pathway is also regulated by a multitude of epigenetic mechanisms, one of which is regulation by microRNA (miRNA) inhibition. This leads us to hypothesize that organ-level abnormalities of miRNA expression patterns are widespread in TSC. The aim of the study was to evaluate the serum profiles of miRNAs in patients with TSC and subependymal giant cell astrocytoma (SEGA) treated with mTOR inhibitor (everolimus).

Methods

Serum microRNA profiling was performed in 10 TSC-patients before and three months after everolimus treatment, as well as in 10 sex- and age-matched healthy controls. MicroRNAs were profiled using qPCR panels (Exiqon).

Results

Of 752 tested miRNAs, 11 showed statistically significant dysregulation in patients with TSC in comparison to controls. The following miRNAs were downregulated in TSC: miR-142-3p, miR-199a-5p, miR-142-5p and miR-136-5p; while miR-130a-3p, miR-378a-3p, miR-130b-3p, miR-192-5p, miR-25-3p, miR-215-5p and miR-222-3p were upregulated in TSC in comparison to the control group. After three months of everolimus treatment, mean dose 5.1 (2.6-9.7) mg/m², seven miRNAs reached expression levels similar to healthy controls, with miR-142-3p and miR-136 showed significant increase over baseline levels in TSC patients. Moreover, miR-222-3p normalization due to treatment differed between patients with mutation in TSC1 and TSC2 gene.

Conclusions

Activation of the mTOR pathway in TSC patients alters serum miRNA levels, which may be partially reversed by an mTOR inhibitor. This indicates the involvement of miRNA dysregulation in the pathogenesis of TSC, linking miRNA profiles with treatment efficiency.

Electronic supplementary material

The online version of this article (doi:10.1186/s13023-016-0512-1) contains supplementary material, which is available to authorized users.

Current state of phenolic and terpenoidal dietary factors and natural products as non-coding RNA/microRNA modulators for improved cancer therapy and prevention

The epigenetic regulation of cancer cells by small non-coding RNA molecules, the microRNAs (miRNAs), has raised particular interest in the field of oncology. These miRNAs play crucial roles concerning pathogenic properties of cancer cells and the sensitivity of cancer cells towards anticancer drugs. Certain miRNAs are responsible for an enhanced activity of drugs, while others lead to the formation of tumor resistance. In addition, miRNAs regulate survival and proliferation of cancer cells, in particular of cancer stem-like cells (CSCs), that are especially drug-resistant and, thus, cause tumor relapse in many cases. Various small molecule compounds were discovered that target miRNAs that are known to modulate tumor aggressiveness and drug resistance. This review comprises the effects of naturally occurring small molecules (phenolic compounds and terpenoids) on miRNAs involved in cancer diseases.

The potential of miRNAs for diagnosis, treatment and monitoring of breast cancer

Dysregulation of microRNAs (miRNAs) has a fundamental role in the initiation, development and progression of several human cancers, including breast cancer (BC), since strong evidence has shown that miRNAs can regulate the expression of oncogenes or tumor suppressor genes. A possible role of miRNAs in the diagnosis in BC has been demonstrated. As miRNAs has been found stable in biofluids, extracellular multiple miRNA profiles have been proposed as diagnostic tools, showing better diagnostic performance than individual miRNAs in BC. In this paper, based on the current literature, we present the role of microRNAs in the diagnosis and therapy monitoring of BC. Furthermore, we report new miRNA-based drugs that could be turned into promising therapy for BC, alone or in combination with conventional therapy. We also discuss how extracellular miRNAs could become new, easily accessible, affordable, non-invasive tools for BC patients.

MiR-19a promotes cell proliferation and invasion by targeting RhoB in human glioma cells

MicroRNA-19a (miR-19a) is upregulated in different types of cancers, including gliomas, but its specific role and function in gliomas have yet to be fully elucidated. In this study, we found that miR-19a was significantly upregulated in human glioma tissues and cell lines. Overexpression of miR-19a by a miR-19a mimic promoted glioma cell proliferation and invasion. In contrast, miR-19a inhibitor suppressed cell proliferation and invasion. Furthermore, by a dual-luciferase reporter assay and expression analysis, we determined that Ras homolog family member B was a direct target of miR-19a. Knockdown of Ras homolog family member B could block cell proliferation and invasion induced by the miR-19a mimic. In conclusion, our study demonstrated that miR-19a upregulation is common in gliomas and that suppression of miR-19a expression inhibits cell proliferation and invasion, which indicates that miR-19a may act as an oncogene in gliomas.

New Concepts in Cancer Biomarkers: Circulating miRNAs in Liquid Biopsies

The effective and efficient management of cancer patients relies upon early diagnosis and/or the monitoring of treatment, something that is often difficult to achieve using standard tissue biopsy techniques. Biological fluids such as blood hold great possibilities as a source of non-invasive cancer biomarkers that can act as surrogate markers to biopsy-based sampling. The non-invasive nature of these “liquid biopsies” ultimately means that cancer detection may be earlier and that the ability to monitor disease progression and/or treatment response represents a paradigm shift in the treatment of cancer patients. Below, we review one of the most promising classes of circulating cancer biomarkers: microRNAs (miRNAs). In particular, we will consider their history, the controversy surrounding their origin and biology, and, most importantly, the hurdles that remain to be overcome if they are really to become part of future clinical practice.

Metastatic breast cancer: the potential of miRNA for diagnosis and treatment monitoring

Breast cancer affects approximately 12 % women worldwide and results in 14 % of all cancer-related fatalities. Breast cancer is commonly categorized into one of four main subtypes (luminal A, luminal B, human epidermal growth factor receptor 2 (HER2) positive and basal), indicating molecular characteristics and informing treatment regimes. The most severe form of breast cancer is metastasis, when the tumour spreads from the breast tissue to other parts of the body. Significantly, the primary tumour subtype affects rates and sites of metastasis. Currently, up to 5 % of patients present with incurable metastasis, with an additional 10–15 % of patients going on to develop metastasis within 3 years of diagnosis. MicroRNAs (miRNAs) are short 21–25 long nucleotides that have been shown to significantly affect gene expression. Currently, >2000 miRNAs have been identified and significantly, specific miRNAs have been found associated with diseases states. Importantly, miRNAs are found circulating in the blood, presenting an opportunity to use these circulating disease-related miRNAs as biomarkers. Clearly, the identification of circulating miRNA specific to metastatic breast cancer presents a unique opportunity for early disease identification and for monitoring disease burden. Currently however, few groups have identified miRNA associated with metastatic breast cancer. Here, we review the literature surrounding the identification of metastatic miRNA in breast cancer patients, highlighting key areas where miRNA biomarker discovery could be beneficial, identifying key concepts, recognizing critical areas requiring further research and discussing potential problems.