Circulating plasma microRNAs as potential markers to identify EGFR mutation status and to monitor epidermal growth factor receptor-tyrosine kinase inhibitor treatment in patients with advanced non-small cell lung cancer

MicroRNA-107 inhibits proliferation and invasion of laryngeal squamous cell carcinoma cells by targeting CACNA2D1 in vitro

Our previous studies have confirmed that α2δ1 has the potential to function as a cancer stem cell marker, and CACNA2D1 is the coding gene of α2δ1. But it is unclear how microRNAs regulate the expression of the CACNA2D1 gene in laryngeal cancer cells. We detected the expressions of α2δ1 protein, microRNA-107, and CACNA2D1 in 40 pairs of laryngeal cancer tissues and adjacent normal tissues. Laryngeal squamous cell carcinoma cells, TU212 and TU686, were cultured and transfected in the blank control group, the agomiR negative control group, the agomiR-107 group, the antagomiR negative control group, or the antagomiR-107 group, and the dual-luciferase reporter assay was employed to assess the regulatory effect of microRNA-107 on CACNA2D1. Then, the effects of microRNA-107 on the biological function of laryngeal squamous cell carcinoma cells were detected by qRT-PCR, Western blot, MTT, cell migration/invasion assay, and cell colony-formation assay. Our data suggested that the protein level of α2δ1, encoded by CACNA2D1, in laryngeal carcinoma tissues was higher than that in adjacent normal tissues, while the expression of microRNA-107 was significantly decreased in laryngeal carcinoma tissues. The dual-luciferase reporter gene assay confirmed that microRNA-107 bound to the 3′-UTR two positions (202-209, 902-908) of CACNA2D1 mRNA. Moreover, the expression of CACNA2D1 and α2δ1 protein were significantly decreased in TU212 and TU686 cells transfected with microRNA-107 expression vectors (P < 0.05), and proliferation, clone formation, migration, and invasion of these cells were also reduced. Furthermore, after knocking down microRNA-107, exactly opposite results were obtained. Overexpression of microRNA-107 can inhibit the proliferation and invasion of laryngeal carcinoma cells in vitro.

Novel Liquid Biomarker Panels for A Very Early Response Capturing of NSCLC Therapies in Advanced Stages

Computed tomography (CT) scans are the gold standard to measure treatment success of non-small cell lung cancer (NSCLC) therapies. Here, we investigated the very early tumor response of patients receiving chemotherapy or targeted therapies using a panel of already established and explorative liquid biomarkers. Blood samples from 50 patients were taken at baseline and at three early time points after therapy initiation. DNA mutations, a panel of 17 microRNAs, glycodelin, glutathione disulfide, glutathione, soluble caspase-cleaved cytokeratin 18 (M30 antigen), and soluble cytokeratin 18 (M65 antigen) were measured in serum and plasma samples. Baseline and first follow-up CT scans were evaluated and correlated with biomarker data. The detection rate of the individual biomarkers was between 56% and 100%. While only keratin 18 correlated with the tumor load at baseline, we found several individual markers correlating with the tumor response to treatment for each of the three time points of blood draws. A combination of the five best markers at each time point resulted in highly significant marker panels indicating therapeutic response (R² = 0.78, R² = 0.71, and R² = 0.71). Our study demonstrates that an early measurement of biomarkers immediately after therapy start can assess tumor response to treatment and might support an adaptation of treatment to improve patients’ outcome.

Noncoding RNAs and Liquid Biopsy in Lung Cancer: A Literature Review

Lung cancer represents a genetically heterogeneous disease with low survival rates. Recent data have evidenced key roles of noncoding RNAs in lung cancer initiation and progression. These functional RNA molecules that can act as both oncogenes and tumor suppressors may become future biomarkers and more efficient therapeutic targets. In the precision medicine era, circulating nucleic acids have the potential to reshape the management and prognosis of cancer patients. Detecting genomic alterations and level variations of circulating nucleic acids in liquid biopsy samples represents a noninvasive method for portraying tumor burden. Research is currently trying to validate the potential role of liquid biopsy in lung cancer screening, prognosis, monitoring of disease progression, and treatment response. However, this method requires complex detection assays, and implementation of plasma genotyping in clinical practice continues to be hindered by discrepancies that arise when compared to tissue genotyping. Understanding the genomic landscape of lung cancer is essential in order to provide useful and innovative research in the age of patient-tailored therapy. In this landscape, the noncoding RNAs play a crucial role due to their target genes that dramatically influence the tumor microenvironment and the response to therapy. This article addresses present and future possible roles of liquid biopsy in lung cancer. It also discusses how the complex role of noncoding RNAs in lung tumorigenesis could influence the management of this pathology.

A five-miRNA panel in plasma was identified for breast cancer diagnosis

Breast cancer (BC) is one of the most common cancers in females. Since early detection can bring prognosis benefit, discovery of novel noninvasive biomarkers for BC diagnosis is in urgent need. In this four‐phase study, we profiled miRNA expression in plasma samples from a total of 257 BC patients and 257 normal controls (NCs). Exiqon miRNA qPCR panel was used to select candidate miRNAs in the screening phase which were further analyzed using qRT‐PCR in the following training, testing and external validation phases. Finally, we identified five plasma miRNAs (let‐7b‐5p, miR‐122‐5p, miR‐146b‐5p, miR‐210‐3p and miR‐215‐5p) whose expression levels were significantly different between BC patients and NCs. A 5‐miRNA panel in plasma with high sensitivity and specificity was then constructed to detect BC. The areas under the receiver‐operating characteristic curves (AUCs) of the panel were 0.683, 0.966, 0.978 for the training, testing and external validation sets, respectively. Expression of the identified miRNAs was further analyzed among 32 pairs of BC tissue and the adjacent normal tissue samples as well as plasma‐derived exosome samples from 32 BC patients vs 32 NCs. Let‐7b‐5p was contrarily down‐regulated in BC tissue. In exosomes samples, only miR‐122‐5p was significantly up‐regulated as in plasma for BC patients. In conclusion, we identified a 5‐miRNA plasma panel (let‐7b‐5p, miR‐122‐5p, miR‐146b‐5p, miR‐210‐3p and miR‐215‐5p) that could serve as a promising biomarker for BC detection.

Long non-coding RNA LINC00485 acts as a microRNA-195 sponge to regulate the chemotherapy sensitivity of lung adenocarcinoma cells to cisplatin by regulating CHEK1

Background

Long non-coding RNAs (lncRNAs) are a family of non-protein-coding RNAs, which have the ability to influence the chemo-resistance of lung adenocarcinoma (LAC). In this study, we explored the mechanism by which LINC00485 competitively binds to microRNA-195 (miR-195) in the regulation of the chemotherapy sensitivity in LAC by regulating checkpoint kinase 1 (CHEK1).

Methods

Microarray analysis was used to screen out LAC related genes, and interaction between CHEK1 and miR-195, as well as that between miR-195 and LINC00485, was further confirmed by RNA-pull down and RIP. LINC00485 expression in LAC cells (A549 and H1299) was determined. The cells were then introduced with miR-195, anta-miR-195, LINC00485 or si-LINC00485 to identify the role of miR-195 and LINC00485 in LAC through evaluating the expression of CHEK1, CHEK1, Bax, Bcl-2, VEGF and HIF-1α in LAC cells by either RT-qPCR or Western blot analysis. After being treated with different concentration of cisplatin, cell proliferation, colony formation and apoptosis were assessed.

Results

LINC00485 acted as a competitive endogenous RNA against miR-195, and miR-195 directly targeted CHEK1. The expression of LINC00485 was higher in LAC cells. The down-regulation of LINC00485 or the up-regulation of miR-195 decreased the expression of CHEK1, Bcl-2, VEGF and HIF-1α, while also increasing the expression of Bax. Moreover, the over-expression of miR-195, or the silencing of LINC00485 enhanced the sensitivity of LAC cells to cisplatin, thereby promoting the apoptosis of LAC cells while suppressing the proliferation.

Conclusion

LINC00485 competitively binds to miR-195 to elevate CHEK1 expression in LAC cells, suggesting that LINC00485 is a novel direction for therapeutic strategies of LAC.

Plasma Level of MicroRNAs, MiR-107, MiR-194 and MiR-210 as Potential Biomarkers for Diagnosis Intestinal-Type Gastric Cancer in Human

Background:

Timely and sensitive diagnosis of gastric cancer is crucial for efficient treatment and survival of the patients. microRNAs have been considered as diagnostic biomarkers in different type of cancers including gastric cancer. In the present study, the expression profile of four microRNAs, miR-103, miR-107, miR-194 and miR-210 were evaluated in patients with intestinal-type of gastric cancer (IGC) in order to assess their diagnosis utility as noninvasive biomarkers.

Methods:

A total number of 100 plasma samples from patients with gastric cancer and healthy controls were obtained and total RNA was extracted using a commercial monophasic solution of phenol and guanidium thiocyanate. Reverse transcription (RT) reactions were performed by specific stem-loop RT primers and M-MuLV RT-enzyme. The expression patterns of microRNAs were assessed using reverse transcription quantitative real-time PCR (RT-qPCR) method and the expression of SNORD47 RNA was used as the reference for normalization.

Results:

The results indicate that the plasma levels of miR-107, miR-194, and miR-210 were significantly lower in patients. Receiver operating characteristic (ROC) curve analysis showed that the patients could be distinguished from healthy individuals at the cutoff levels of 0.504, 0.266, and 0.394 of miR-107, miR-194, and miR-210, respectively. On the other hand, the expression levels of these miRNAs were not significantly different in different clinicopathological stages of the disease.

Conclusion:

These findings suggest that the plasma levels of miR-107, miR-194 and miR-210 were downregulated in patients with ICG and propose these molecules as potential non-invasive biomarkers for detection of IGC.

MicroRNAs as a drug resistance mechanism to targeted therapies in EGFR-mutated NSCLC: Current implications and future directions

The introduction of EGFR-tyrosine kinase inhibitors (TKIs) has revolutionized the treatment and prognosis of non-small cell lung cancer (NSCLC) patients harboring epidermal growth factor receptor (EGFR) mutations. However, these patients display disease progression driven by the onset of acquired mechanisms of drug resistance that limit the efficacy of EGFR-TKI to no longer than one year. Moreover, a small fraction of EGFR-mutated NSCLC patients does not benefit from this targeted treatment due to primary (i.e. intrinsic) mechanisms of resistance that preexist prior to TKI drug treatment. Research efforts are focusing on deciphering the distinct molecular mechanisms underlying drug resistance, which should prompt the development of novel antitumor agents that surmount such chemoresistance modalities. The capability of microRNAs (miRNAs) to regulate the expression of many oncogenic pathways and their central role in lung cancer progression, provided new directions for research on prognostic biomarkers, as well as innovative tools for predicting patients' response to systemic therapies. Recent evidence suggests that modulation of key miRNAs may also reverse oncogenic signaling pathways, and potentiate the cytotoxic effect of anti-cancer therapies. In this review, we focus on the putative emerging role of miRNAs in modulating drug resistance to EGFR-TKI treatment in EGFR-mutated NSCLC. Moreover, we discuss the current implications of miRNAs analyses in the clinical setting, using both tissue and liquid biopsies, as well as the future potential use of miRNA-based therapies in overcoming resistance to targeted agents like TKIs.

Profiling of 179 miRNA Expression in Blood Plasma of Lung Cancer Patients and Cancer-Free Individuals

Lung cancer is one of major cancers, and survival of lung cancer patients is dictated by the timely detection and diagnosis. Cell-free circulating miRNAs were proposed as candidate biomarkers for lung cancer. These RNAs are frequently deregulated in lung cancer and can persist in bodily fluids for extended periods of time, shielded from degradation by membrane vesicles and biopolymer complexes. To date, several groups reported the presence of lung tumour-specific subsets of miRNAs in blood. Here we describe the profiling of blood plasma miRNAs in lung cancer patients, healthy individuals and endobronchitis patients using miRCURY LNA miRNA qPCR Serum/Plasma Panel (Exiqon). From 241 ratios differently expressed between cancer patients and healthy individuals 19 miRNAs were selected for verification using the same platform. LASSO-penalized logistic regression model, including 10 miRNA ratios comprised of 14 individual miRNAs discriminated lung cancer patients from both control groups with AUC of 0.979.

Unique circulating microRNAs in relation to EGFR mutation status in Japanese smoker male with lung adenocarcinoma

The incidence of lung adenocarcinoma has been increasing recently in smokers. The molecular target therapy has been developed for lung adenocarcinoma patients harboring EGFR gene mutation. However, the treatment modalities for patients without mutation are currently limited. Thus, analysis of EGFR gene mutation status at early stage is important strategy to classify the patients for improving treatments and prognosis efficiently. This study aimed to identify microRNA (miRNA) signature in relation to mutation status in EGFR gene in early stage of lung adenocarcinoma male patients with smoking history. MiRNA profiles were assessed by microarray in paired plasma and tissue pooled from 10 EGFR wild type (EGFR-wt) and 10 EGFR mutated (EGFR-mut) patients. Expressions of selected miRNAs were verified further by real-time qRT-PCR in 83 plasma samples consisting of 55 EGFR-wt patients and 28 EGFR-mut patients and their correlation with clinicopathological parameters and EGFR gene mutation status were evaluated. We found that seven miRNAs (miR-16-5p, miR-23a-3p, miR-103a-3p, miR122-5p, miR-223-3p, miR-346 and miR-451a) were differentially expressed in stage I and stage I+II. Especially, miR-23a-3p was only miRNA shown higher expression in EGFR-wt patients than EGFR-mut patients. Thus, our findings could be useful non-invasive biomarkers to differentiate mutation status in EGFR gene in smoker lung adenocarcinoma male patients.