Expression levels of miR-143-3p and -424-5p in colorectal cancer and their clinical significance

CCDC144NL-AS1/hsa-miR-143-3p/HMGA2 interaction: In-silico and clinically implicated in CRC progression, correlated to tumor stage and size in case-controlled study; step toward ncRNA precision

Unravel the regulatory mechanism of lncRNA CCDC144NL-AS1 in CRC hsa-miR-143-3p, downstream protein HMGA2 interaction arm, association with clinicopathological characteristics. Using peripheral blood as liquid biopsy from 60 CRC patients and 30 controls. The expression levels of CCDC144NL-AS1 and hsa-miR-143-3p detected by qRT-PCR. CCDC144NL-AS1 expression was significantly upregulated in CRC patients' sera, associated with worse CRC clinicopathological features regarding the depth of tumor invasion and highly significant difference between tumor stages 3 and 4 and tumor stages 2 and 4. While, hsa-miR-143-3p expression was downregulated in CRC patients by 4.5-fold change when compared to the control subjects (p < 0.0001) and HMGA2 increased in CRC patients than controls 19.59 ng/μL and 5.377 ng/μL, respectively (p < 0.0001) with significant difference between tumor stages 3 and 4 as well as tumor stages 2 and 4. CRC patients with large tumor size showed upregulation in CCDC144NL-AS1 expression and HMGA2 levels compared to those with small tumor size (p-value = 0.0365 and 0.013, respectively). CCDC144NL-AS1 and HMGA2 were positively correlated, whereas lncRNA CCDC144NL-AS1 and hsa-miR-143-3p were negatively correlated. Conclusion: As an interaction arm CCDC144NL-AS1/hsa-miR-143-3p/HMGA2 were correlated to CRC stages 2-4. Therefore, this interaction arm expression clinically and in silico approved, would direct treatment precision in the near future.

Targeting of AKT1 by miR-143-3p Suppresses Epithelial-to-Mesenchymal Transition in Prostate Cancer

An altered expression of miR-143-3p has been previously reported in prostate cancer where it is purported to play a tumor suppressor role. Evidence from other cancers suggests miR-143-3p acts as an inhibitor of epithelial-to-mesenchymal transition (EMT), a key biological process required for metastasis. However, in prostate cancer the interaction between miR-143-3p and EMT-associated mechanisms remains unclear. Therefore, this paper investigated the link between miR-143-3p and EMT in prostate cancer using in vitro and in silico analyses. PCR detected that miR-143-3p expression was significantly decreased in prostate cancer cell lines compared to normal prostate cells. Bioinformatic analysis of The Cancer Genome Atlas Prostate Adenocarcinoma (TCGA PRAD) data showed a significant downregulation of miR-143-3p in prostate cancer, correlating with pathological markers of advanced disease. Functional enrichment analysis confirmed the significant association of miR-143-3p and its target genes with EMT. The EMT-linked gene AKT1 was subsequently shown to be a novel target of miR-143-3p in prostate cancer cells. The in vitro manipulation of miR-143-3p levels significantly altered the cell proliferation, clonogenicity, migration and expression of EMT-associated markers. Further TCGA PRAD analysis suggested miR-143-3p tumor expression may be a useful predictor of disease recurrence. In summary, this is the first study to report that miR-143-3p overexpression in prostate cancer may inhibit EMT by targeting AKT1. The findings suggest miR-143-3p could be a useful diagnostic and prognostic biomarker for prostate cancer.

Baseline Expression of Exosomal miR-92a-3p and miR-221-3p Could Predict the Response to First-Line Chemotherapy and Survival in Metastatic Colorectal Cancer

The status of predictive biomarkers in metastatic colorectal cancer is currently underdeveloped. Our study aimed to investigate the predictive value of six circulating exosomal miRNAs derived from plasma (miR-92a-3p, miR-143-3p, miR-146a-5p, miR-221-3p, miR-484, and miR-486-5p) for chemosensitivity, resistance patterns, and survival. Thirty-one metastatic colorectal cancer patients were selected before receiving first-line irinotecan- or oxaliplatin-based chemotherapy. Blood samples were harvested at baseline and 4-6 months after the initiation of chemotherapy. The levels of exosomal expression for each miRNA were analyzed by qPCR. Our results for patients receiving first-line FOLFOX showed significantly higher baseline levels of miR-92a-3p (p = 0.007 **), miR-146a-5p (p = 0.036 *), miR-221-3p (p = 0.047 *), and miR-484 (p = 0.009 **) in non-responders (NR) vs. responders (R). Of these, miR-92a-3p (AUC = 0.735), miR-221-3p (AUC = 0.774), and miR-484 (AUC = 0.725) demonstrated a predictive ability to discriminate responses from non-responses, regardless of the therapy used. Moreover, Cox regression analysis indicated that higher expression levels of miR-92a-3p (p = 0.008 **), miR-143-3p (p = 0.009 **), miR-221-3p (p = 0.016 *), and miR-486-5p (p = 0.019 *) at baseline were associated with worse overall survival, while patients expressing higher baseline miR-92a-3p (p = 0.003 **) and miR-486-5p (p = 0.003 **) had lower rates of progression-free survival. No predictive values for candidate microRNAs were found for the post-chemotherapy period. In line with these findings, we conclude that the increased baseline exosomal expression of miR-92a-3p and miR-221-3p seems to predict a lack of response to chemotherapy and lower OS. However, further prospective studies on more patients are needed before drawing practice-changing conclusions.

miR-143-3p shuttled by M2 macrophage-derived extracellular vesicles induces progression of colorectal cancer through a ZC3H12A/C/EBPβ axis-dependent mechanism

Extracellular vesicles (EVs) exhibit pivotal functions in cancer via intercellular communication through shuttling microRNA (miRNA) and protein. Therefore, we aim to elucidate the function of EVs containing miR-143-3p derived from M2 macrophages in colorectal cancer (CRC). EVs derived from M2 macrophages were isolated and characterized. Expression changes in miR-143-3p were calculated in the EVs. The effects of M2 macrophage-derived EV carrying miR-143-3p on cell biological processes and in vivo tumorigenic ability concerning ZC3H12A were examined. EVs derived from M2 macrophages could stimulate the aggressive tumor biology of CRC cells. Meanwhile, in vivo results showed that M2 macrophage-derived EVs facilitated tumor growth and epithelial-mesenchymal transition. M2 macrophage-secreted EVs could transfer miR-143-3p to CRC cells, in which miR-143-3p bound to the 3'UTR of ZC3H12A and inhibited its expression, leading to elevation of the expression of transcription factor C/EBPβ. Overall, M2 macrophage-derived EV miR-143-3p inhibits ZC3H12A gene and increases C/EBPβ expression to facilitate the development of CRC, which provides novel targets for the molecular treatment of CRC.

Fusobacterium nucleatum induces excess METTL3-mediated miR-4717-3p maturation to promote colorectal cancer cell proliferation

Fusobacterium nucleatum (F. nucleatum) infection plays vital roles in colorectal cancer (CRC) progression. Over-expression of miR-4717-3p (miR-4717) has been previously up-regulated in F. nucleatum positive CRC tissues, however, the underlying mechanism is unknown. In this study, we found that miR-4717 promoted CRC cell proliferation in vitro and growth of CRC in vivo upon F. nucleatum infection. MiR-4717 suppressed the expression of mitogen-activated protein kinase kinase 4 (MAP2K4), a tumor suppressor, by directly targeting its 3'UTR. Furthermore, we confirmed that methyltransferase-like 3 (METTL3) -dependent m⁶ A methylation could methylate pri-miR-4717, which further promoted the maturation of pri-miR-4717, and METTL3 positively regulated CRC cell proliferation through miR-4717/MAP2K4 pathways. In conclusion, F. nucleatum-induced miR-4717 excessive maturation via METTL3-dependent m⁶ A modification promotes CRC cell proliferation, which provides a potential therapeutic target and diagnostic biomarker for CRC.

The Role and Interactions of Programmed Cell Death 4 and its Regulation by microRNA in Transformed Cells of the Gastrointestinal Tract

Data from GLOBOCAN 2020 estimates that there were 19.3 million new cases of cancer and 10.0 million cancer-related deaths in 2020 and that this is predicted to increase by 47% in 2040. The combined burden of cancers of the gastrointestinal (GI) tract, including oesophageal-, gastric- and colorectal cancers, resulted in 22.6% of the cancer-related deaths in 2020 and 18.7% of new diagnosed cases. Understanding the aetiology of GI tract cancers should have a major impact on future therapies and lessen this substantial burden of disease. Many cancers of the GI tract have suppression of the tumour suppressor Programmed Cell Death 4 (PDCD4) and this has been linked to the expression of microRNAs which bind to the untranslated region of PDCD4 mRNA and either inhibit translation or target the mRNA for degradation. This review highlights the properties of PDCD4 and documents the evidence for the regulation of PDCD4 expression by microRNAs in cancers of the GI tract.

Long Non-coding RNA LINC01426 Contributes to the Malignant Behaviors of NSCLC Via Acting As a Sponge for miR-143-3p

Recently, long non-coding RNA (lncRNA) is proved to play critical roles in non-small cell lung cancer (NSCLC) progression. However, the detailed effects of LINC01426 in NSCLC and its functional mechanism remain unknown. The expression of LINC01426, microRNA-143-3p (miR-143-3p), and Ubiquitin-specific peptidase 28 (USP28) was assessed by quantitative real-time polymerase chain reaction (RT-qPCR). The colony-forming ability was determined by colony-forming assay. 5-ethynyl-2'-deoxyuridine (EdU) staining assay was performed to evaluate cell proliferation. The migrated and invaded abilities of cells were measured by transwell assays. Flow cytometry was used to examine cell apoptosis. The protein expression was analyzed by Western blot analysis. The glycolysis ability was analyzed by commercial kits. Dual-luciferase reporter assay, RNA immunoprecipitation (RIP) assay, and RNA pull-down assay were used to confirm relationship among LINC01426, miR-143-3p, and USP28. A xenograft experiment was conducted to explore the effects of LINC01426 inhibition in vivo. Our results confirmed that LINC01426 and USP28 expression were increased, while miR-143-3p expression was decreased in NSCLC tissues and cells. Further functional experiments demonstrated that LINC01426 inhibition markedly impaired cell proliferation, migration, invasion, autophagy, and glycolysis while induced apoptosis in NSCLC cells, and LINC01426 derived malignant behaviors of NSCLC cells by sponging miR-143-3p. Additionally, LINC01426 regulated USP28 expression by sponging miR-143-3p. USP28 overexpression partly overturned the inhibitory effect of miR-143-3p on NSCLC progression. Consistently, silencing of LINC01426 significantly inhibited the growth of NSCLC tumor in vivo. LINC01426 accelerated the malignant progression of NSCLC. Mechanistically, LINC01426 acted as a competing endogenous RNA (ceRNA) for miR-143-3p to upregulate USP28 expression.

Sequence Requirements for miR-424-5p Regulating and Function in Cancers

MiRNAs (microRNAs) are the most abundant family of small noncoding RNAs in mammalian cells. Increasing evidence shows that miRNAs are crucial regulators of individual development and cell homeostasis by controlling various biological processes. Therefore, miRNA dysfunction can lead to human diseases, especially in cancers with high morbidity and mortality worldwide. MiRNAs play different roles in these processes. In recent years, studies have found that miR-424-5p is closely related to the occurrence, development, prognosis and treatment of tumors. This review discusses how miR-424-5p plays a role in different kinds of cancers from different stages of tumors, including its roles in (i) promoting or inhibiting tumorigenesis, (ii) regulating tumor development in the tumor microenvironment and (iii) participating in cancer chemotherapy. This review provides a deep discussion of the latest findings on miR-424-5p and its importance in cancer, as well as a mechanistic analysis of the role of miR-424-5p in various tissues through target gene verification and pathway analysis.

Identifying Diagnostic MicroRNAs and Investigating Their Biological Implications in Rectal Cancer

IMPORTANCE

Accurate clinical staging is important in rectal cancer because it determines the appropriate treatment and prognosis. Despite the use of multiple diagnostic imaging tools, it is sometimes difficult to clinically distinguish stage I tumors from stage II or III locally advanced disease. Identification of differentiating microRNAs (miRNAs) between these 2 groups may improve the clinical diagnostic power and provide insight into the biology of tumor progression.

OBJECTIVES

To investigate differences in the expression of miRNAs in stage I vs stage II or III rectal cancers and integrate matched mRNA profiling data to identify possible functional roles of these miRNAs.

DESIGN, SETTING, AND PARTICIPANTS

The primary tumor specimens from patients who were enrolled in 2 prospective clinical trials between March 24, 2004, and November 16, 2012 (American College of Surgeons Oncology Group [ACOSOG] Z6041 and Timing of Rectal Cancer Response to Chemoradiation [TIMING]) were sequenced to arrive at a set of 127 cases (41 stage I and 86 stage II or III tumors) with matched miRNA and messenger RNA (mRNA) profiling data. These findings were also evaluated in an independent cohort of 127 patient specimens (29 stage I and 98 stage II or III tumors) from The Cancer Genome Atlas Rectum Adenocarcinoma (TCGA-READ) that also had matched miRNA and mRNA data. Data analysis was performed from September 1, 2019, to September 1, 2020.

MAIN OUTCOMES AND MEASURES

Alterations in miRNA expression between stage I and stage II or III tumors and their potential gene targets.

RESULTS

A total of 254 pretreatment rectal adenocarcinoma specimens were analyzed in this study as 2 distinct cohorts: 127 samples in the ACOSOG/TIMING (stage I group: 27 [66%] male; mean [SD] age, 64.4 [10.8] years; stage II or III group: 47 [55%] male; mean [SD] age, 57.0 [11.4] years), and another 127 samples from TCGA-READ (stage I group: 17 [59%] male; mean [SD] age, 63.6 [12.0] years; stage II or III group: 48 [49%] male; mean [SD] age, 64.5 [11.4] years). A total of 19 miRNAs were overexpressed in stage II or III vs stage I tumors in both cohorts. This miRNA signature had an excellent discriminative value for distinguishing stage II or III from stage I rectal tumors (area under the curve, 0.88; 95% CI, 0.83-0.94 in ACOSOG/TIMING cohort and area under the curve, 0.84; 95% CI, 0.77-0.91 in the TCGA-READ cohort). Integrative analysis revealed 3 miRNA-mRNA pairs that exhibited significant correlations in both cohorts: miR-31-5p-SATB2, miR-143-3p-KLF5, and miR-204-5p-EZR.

CONCLUSIONS AND RELEVANCE

This diagnostic study found that many of the dysregulated miRNAs in stage II or III vs stage I rectal cancers have biological implications for tumor progression. The results of this study suggest that these miRNAs could assist as diagnostic biomarkers to better identify patients with locally advanced rectal cancer.

lncRNA TINCR attenuates the proliferation and invasion, and enhances the apoptosis of cutaneous malignant melanoma cells by regulating the miR‑424‑5p/LATS1 axis

Cutaneous malignant melanoma (CMM) is responsible for ≥1/2 of skin cancer‑related mortalities. The aberrant expression of long non‑coding RNAs (lncRNAs) has been associated with the development of CMM. However, to the best of our knowledge, the role of the lncRNA TINCR ubiquitin domain containing (TINCR) in CMM has not been previously investigated, and thus, the current study aimed to evaluate this in vitro and in vivo. Reverse transcription‑quantitative PCR (RT‑qPCR) was used to analyze microRNA (miR)‑424‑5p expression, and RT‑qPCR and western blotting were used to measure TINCR, large tumor suppressor kinase 1 (LATS1), cellular communication network factor 2 (CTGF), cellular communication network factor 1 (CCN1) and AXL receptor tyrosine kinase (AXL) mRNA and protein expression levels, respectively. Cell Counting Kit‑8, flow cytometry and Transwell assays were used to detect the proliferation, apoptosis and invasion of CMM cell lines, respectively. The binding sites between TINCR and miR‑424‑5p were predicted using the miRDB database. A dual luciferase reporter assay and RT‑qPCR were used to identify the relationship between TINCR and miR‑424‑5p in CMM cell lines. The bioinformatics analysis revealed that TINCR was one of the most significantly downregulated lncRNAs in CMM, and advanced stage CMM tissues showed the greatest decrease in TINCR expression. Moreover, in the collected CMM tissues and tested cell lines of the current study, TINCR expression was found to be downregulated compared with the respective controls. Notably, TINCR overexpression inhibited the expression levels of CTGF, CCN1 and AXL, decreased the proliferation and invasion, and induced the apoptosis of CMM cell lines. In addition, a mutual binding association was identified between miR‑424‑5p and TINCR in CMM cells. LATS1, a target of miR‑424‑5p, was found to be positively regulated by TINCR. TINCR activated Hippo signaling and repressed the activity of Yes 1 associated transcriptional regulator by regulating LATS1 expression, while LATS1 knockdown reversed the effect of TINCR overexpression on CMM cells. Collectively, the findings of the present study suggested that TINCR may attenuate the progression of CMM by regulating the miR‑424‑5p/LATS1 signaling axis. These results indicated that TINCR may play a tumor suppressive role in CMM.

Faecal miRNA profiles associated with age, sex, BMI, and lifestyle habits in healthy individuals

For their stability and detectability faecal microRNAs represent promising molecules with potential clinical interest as non-invasive diagnostic and prognostic biomarkers. However, there is no evidence on how stool miRNA profiles change according to an individual’s age, sex, and body mass index (BMI) or how lifestyle habits influence the expression levels of these molecules. We explored the relationship between the stool miRNA levels and common traits (sex, age, BMI, and menopausal status) or lifestyle habits (physical activity, smoking status, coffee, and alcohol consumption) as derived by a self-reported questionnaire, using small RNA-sequencing data of samples from 335 healthy subjects. We detected 151 differentially expressed miRNAs associated with one variable and 52 associated with at least two. Differences in miR-638 levels were associated with age, sex, BMI, and smoking status. The highest number of differentially expressed miRNAs was associated with BMI (n = 92) and smoking status (n = 84), with several miRNAs shared between them. Functional enrichment analyses revealed the involvement of the miRNA target genes in pathways coherent with the analysed variables. Our findings suggest that miRNA profiles in stool may reflect common traits and lifestyle habits and should be considered in relation to disease and association studies based on faecal miRNA expression.

The Clinical Significance and Functional Role of miR-466 in Gastric Cancer Peritoneal Metastasis

The prognosis of metastasis gastric cancer patients remains poor and the identification of novel molecular markers will improve the management of gastric cancer patients. The present study aimed to investigate the clinical significance and functional role of miR-466 in gastric cancer peritoneal metastasis. miR-466 expression was confirmed by RT-qPCR. The biological functions were examined by MTT assay, Transwell migration, and invasion assays. The Kaplan-Meier survival curve and multivariate Cox regression analysis were used to investigate the clinical role of miR-466. The logistic regression analysis was performed to reveal the risk factors associated with peritoneal metastasis. miR-466 expression was downregulated in gastric cancer cell lines, tumor tissues, and peritoneal metastasis tissues compared with respective controls. Increased miR-466 expression inhibited proliferation, migration, and invasion of gastric cancer cells. Besides, the lower expression of miR-466 in gastric cancer patients was associated with peritoneal dissemination. Furthermore, multivariate Cox proportional hazard regression analyses demonstrated miR-466 expression level as an independent predictor of prognosis of gastric cancer. The present study provides novel evidence for the clinical and biological significance of miR-466 expression as a possible biomarker for the prognosis and identifying patients with peritoneal metastasis, as well as a potential therapeutic target in patients with gastric cancer.

Long noncoding RNA AC092155 facilitates osteogenic differentiation of adipose-derived stem cells through the miR-143-3p/STMN1 axis

BACKGROUND

Numerous studies have demonstrated that long noncoding RNAs (lncRNAs) induce osteogenesis in adipose-derived stem cells (ADSCs). This study aimed to explore the role of lncRNAs AC092155 in promoting osteogenic differentiation of ADSCs.

METHODS

MicroRNA (miRNA) and lncRNA sequencing were performed in ADSCs that underwent normal or osteogenic induction. Differentially expressed miRNAs and lncRNAs were identified using R software. The relative expression levels of lncRNA AC092155, miR-143-3p, and STMN1 during the process of osteogenic induction were determined by real-time polymerase chain reaction (RT-PCR). ADSCs were then transfected with agomiR-143-3p and pcDNA3.1-sh-lncRNA AC092155. Alkaline phosphatase (ALP) and alizarin red staining (ARS) were used to confirm the regulatory function of the lncRNA AC092155/miR-143-3p/STMN1 axis in osteogenic differentiation of ADSCs.

RESULTS

lncRNA AC092155 was significantly upregulated in ADSCs following induction in the osteogenic medium. lncRNA AC092155 and STMN1 mimics increase the markers of osteogenic differentiation in the early and late phases, which was reflected in increased ALP activity as well as the higher deposition of calcium nodules. An miR-143-3p mimic showed the opposite effect. Luciferase reporter gene analysis demonstrated that lncRNA AC092155 directly targets miR-143-3p. Moreover, the lncRNA AC092155/miR-143-3p/STMN1 regulatory axis was found to activate the Wnt/β-catenin signaling pathway.

CONCLUSIONS

lncRNA AC092155 contributes to the osteogenic differentiation of ADSCs. The lncRNA AC092155/miR-143-3p/STMN1 axis may be a new therapeutic target for bone-related diseases.

Assessment of circulating microRNA specific for patients with familial adenomatous polyposis

Circulating microRNAs (miRNAs) are considered promising biomarkers for diagnosis, prognosis, and treatment efficacy of diseases. However, usefulness of circulating miRNAs as biomarkers for hereditary gastrointestinal diseases have not been confirmed yet. We explored circulating miRNAs specific for patients with familial adenomatous polyposis (FAP) as a representative hereditary gastrointestinal disease. Next-generation sequencing (NGS) indicated that plasma miR-143-3p, miR-183-5p, and miR-885-5p were candidate biomarkers for five FAP patients compared to three healthy donors due to moderate copy number and significant difference. MiR-16-5p was considered as an internal control due to minimum difference in expression across FAP patients and healthy donors. Validation studies by real-time PCR showed that mean ratios of maximum expression and minimum expression were 2.2 for miR-143-3p/miR-16-5p, 3.4 for miR-143-3p/miR-103a-3p, 5.1 for miR-183-5p/miR-16-5p, and 4.9 for miR-885-5p/miR-16-5p by using the samples collected at different time points of eight FAP patients. MiR-143-3p/16-5p was further assessed using specimens from 16 FAP patients and 7 healthy donors. MiR-143-3p was upregulated in FAP patients compared to healthy donors (P = 0.04), but not significantly influenced by clinicopathological features. However, miR-143-3p expression in colonic tumors was rare for upregulation, although there was a significant difference by existence of desmoid tumors. MiR-143-3p transfection significantly inhibited colorectal cancer cell proliferation compared to control microRNA transfection. Our data suggested regulation of miR-143-3p expression differed by samples (plasma or colonic tumors) in most FAP patients. Upregulation of plasma miR-143-3p expression may be helpful for diagnosis of FAP, although suppressive effect on tumorigenesis seemed insufficient in FAP patients.

miR-424-5p reduces 5-fluorouracil resistance possibly by inhibiting Src/focal adhesion kinase signalling-mediated epithelial-mesenchymal transition in colon cancer cells

OBJECTIVES

miR-424-5p negatively regulates various malignant biological behaviours in tumour cells. We explored the relationship between miR-424-5p and 5-fluorouracil resistance in colon cancer cells.

METHODS

We developed 5-fluorouracil-resistant HT-29 cells and detected miR-424-5p expression using real-time fluorescence quantitative PCR. Cell viability was assessed using Cell Counting Kit-8 (CCK-8) assay. Immunofluorescence and western blotting were performed to determine protein levels. Apoptosis was detected by Annexin V-FITC/PI staining.

KEY FINDINGS

miR-424-5p was downregulated in 5-fluorouracil-resistant HT-29 cells. A miR-424-5p mimic enhanced the sensitivity of the resistant cells to 5-fluorouracil, whereas a miR-424-5p inhibitor promoted 5-fluorouracil resistance in HT-29 cells. Furthermore, the miR-424-5p mimic downregulated vimentin and upregulated E-cadherin in 5-fluorouracil-resistant HT-29 cells, whereas the miR-424-5p inhibitor exhibited opposite effects. The miR-424-5p inhibitor significantly inhibited 5-fluorouracil-induced HT-29 cell apoptosis and Src and focal adhesion kinase phosphorylation, whereas the miR-424-5p mimic showed opposite effects. Pretreatment with Src inhibitor 1 or focal adhesion kinase inhibitor 2 blocked the increase in Src and focal adhesion kinase phosphorylation and vimentin expression level and the decrease in E-cadherin expression level in miR-424-5p inhibitor-exposed HT-29 cells.

CONCLUSIONS

miR-424-5p suppressed epithelial-mesenchymal transition by inhibiting the Src/focal adhesion kinase signalling pathway to reduce 5-fluorouracil resistance in colon cancer cells.

MicroRNAs as potential investigative and predictive biomarkers in colorectal cancer

Colorectal cancer (CRC) is a noticeable reason of cancer-associated deaths with a high incidence and mortality rate. Countless effort have been put into the improving clinical management of CRC patients including more effective tools and a wide variety of biomarkers for diagnostic, prognostic or predictive purposes. In recent years, dysregulated miRNAs have been emerged as highly sensitive and specific markers to manage CRC in an effective way. They can play key roles in carcinogenesis as potential oncogenes, tumor suppressors or regulators of cancer network. Therefore, miRNAs may serve as molecular tools that can be quantified and used in diagnostic and prognostic approaches. Growing evidence also suggests that forced expression of tumor suppressor miRNAs or inhibiting the oncogene ones, can be used as a novel treatment strategy. In this review, we focus on the clinical applications of miRNAs as promising biomarkers of early cancer detection, prognosis and treatment.

LncRNA MAFG-AS1 Promotes the Progression of Bladder Cancer by Targeting the miR-143-3p/COX-2 Axis

<b><i>Background:</i></b> Long noncoding RNAs (lncRNAs) are potential biomarkers that are very important for the development of cancer. Studies show that lncRNAs are significantly correlated with the carcinogenesis and progression of bladder cancer (BLCA). In this research, we aimed at probing into the role of lncRNA MAFG-AS1 in the tumorigenesis of BLCA. <b><i>Methods:</i></b> RT-qPCR was employed to detect MAFG-AS1 expression in BLCA tissues and cells. MAFG-AS1 siRNA and overexpression plasmid were transfected into 5637 and T24 BLCA cell lines to inhibit or upregulate MAFG-AS1 expression, respectively, and then the regulatory functions of MAFG-AS1 on BLCA cell proliferation, migration, and invasion were assessed using cell counting kit-8 (CCK-8) assay, EdU method, and Transwell experiments, respectively. Dual-luciferase reporter assay and RNA immunoprecipitation were conducted to validate the targeting relationships between MAFG-AS1 and miR-143-3p, and miR-143-3p and COX-2. In addition, miR-143-3p was repressed in MAFG-AS1-silenced 5637 and T24 cell lines, and the function of MAFG-AS1/miR-143-3p axis in BLCA cells was further evaluated. The regulatory effects of MAFG-AS1 and miR-143-3p on the expression of COX-2 protein were detected by Western blot. <b><i>Results:</i></b> MAFG-AS1 was remarkably upregulated in BLCA patient tissues and cell lines, and its high expression was closely related to histological grade, tumor size, and lymph node metastasis. Silencing of MAFG-AS1 inhibited BLCA cell proliferation, metastasis, and invasion, while overexpression of MAFG-AS1 in BLCA cells had opposite biological effects. MAFG-AS1 was proved to target miR-143-3p to repress its expression. Moreover, it was confirmed that MAFG-AS1 and miR-143-3p could modulate COX-2 expression. <b><i>Conclusion:</i></b> The MAFG-AS1/miR-143-3p/COX-2 axis contributes to BLCA progression.

MicroRNA-623 inhibits tumor progression and is a predictor of poor prognosis of breast cancer

Dysregulated microRNAs (miRNAs) serve vital roles in the progression and prognosis of breast cancer. miR-623 has been reported to influence the progression of numerous other cancers, such as lung adenocarcinoma and hepatocellular carcinoma, however, its role in breast cancer remains unclear. In the present study, the mRNA expression of miR-623 was studied in 121 pairs of breast cancer and adjacent normal tissues and cultured cell lines by reverse-transcription quantitative PCR. The association between miR-623 expression and clinical characteristics or the overall survival rate of patients was investigated by the χ² test or Cox regression analysis, respectively. The role of miR-623 in cell proliferation, migration and invasion of breast cancer cells was evaluated by cell transfection to regulate miR-623 expression and the CCK8 and Transwell assays, respectively. miR-623 was downregulated in breast cancer tissues and cell lines compared with normal tissues and breast epithelial cell lines. The χ² test demonstrated that the downregulation of miR-623 was associated with the tumor node metastasis (TNM) stage of patients with breast cancer. miR-623 and TNM stage were considered as two independent prognostic factors for breast cancer. Additionally, cell proliferation, migration, and invasion of breast cancer cells were promoted by the downregulation of miR-623, while upregulation of miR-623 led to inhibition of the aforementioned processes. Downregulation of miR-623 in breast cancer is associated with the development of breast cancer and indicates a poor prognosis of patients. The downregulation of miR-623 promotes cell proliferation, migration and invasion of breast cancer. The findings of the present study indicate that miR-623 functions as a prognosis biomarker and a tumor suppressor in breast cancer, which provides a potential therapeutic target for patients with breast cancer.

MiR-143-3p targets ATG2B to inhibit autophagy and promote endothelial progenitor cells tube formation in deep vein thrombosis

Deep vein thrombosis (DVT) is a common disease in vascular surgery. In recent study, microRNA (miRNA) plays a regulatory role in function of Endothelial progenitor cells (EPCs), which showed promising therapeutic choice for DVT. However, the function of miR-143-3p in EPCs remains incomplete. Flow cytometry was used to identify EPCs surface markers. Cell viability, migration, invasion and tube formation of EPCs were detected by 3-[4,5-dimethylthylthiazol-2-yl]-2,5 diphenyltetrazolium broide (MTT), wound healing, transwell and tube formation assay, respectively. TargetScan was used to predict miR-143-3p targeting genes. Dual-luciferase report assay was used to verify the interactions between miR-143-3p and autophagy-related 2B (ATG2B). Quantitative reverse transcription polymerase chain reaction (qRT-PCR) was used to examine the mRNA expression levels of ATG2B and miR-143-3p. Western blot was used to examine the protein expression levels of ATG2B, LC3 and p62. The cultured EPCs showed cobblestone morphology and were identified by cell surface markers. Overexpression of miR-143-3p enhanced the viability, migration, invasion and tube formation of EPCs, but low expression of miR-143-3p obtained the reverse results. ATG2B directly bound to miR-143-3p. Overexpression of miR-143-3p reduced the expression of ATG2B, but low expression of miR-143-3p increased. Overexpression of miR-143-3p decreased the expression of LC3I/II, but increased the expression of p62. Overexpression of ATG2B reversed the above-mentioned effects of EPCs which regulated by overexpression of miR-143-3p. MiR-143-3p targets ATG2B to modulate the function of EPCs and recanalization and resolution of DVT.

MiR-874 Inhibits Cell Proliferation, Migration, and Invasion of Glioma Cells and Correlates with Prognosis of Glioma Patients

Previous studies showed that miR-874 expression was abnormally expressed in many tumors. However, the potential role of miR-874 in glioma remains a mystery. This study aimed to investigate its expression, clinical significance, and cellular function in glioma. A total of 105 glioma patients were enrolled in the present study. The RT-qPCR analysis was used to detect the expression of miR-874 in glioma tissues and cells. The χ² test was used to analyze the association between miR-874 expression and clinical characteristics of patients. Kaplan-Meier method and multivariate Cox regression assays were used to analyze the prognostic value of miR-874 in glioma. Cell counting kit-8 and Transwell assays were used to explore the alterations in a series of cancer-related phenotypes affected by miR-874, including cell proliferation, migration, and invasion capacities. The expression of miR-874 was significantly downregulated in human glioma tissue specimens and cell lines. Furthermore, the expression of miR-874 was associated with tumor size, KPS, and WHO grade. The decreased expression of miR-874 was associated with shorter overall survival. Then functional assays indicated that upregulation of miR-874 suppressed proliferation, migration, and invasion of glioma cells in vitro. The present study indicated that miR-874 inhibited cell proliferation, migration, and invasion of glioma cells and might be a novel prognostic biomarker and potential therapeutic target for glioma.

MiR-424-5p Inhibits Proliferation, Invasion and Promotes Apoptosis and Predicts Good Prognosis in Glioma by Directly Targeting BFAR

The biological function of miRNA (miR)-424-5p in glioma has not been clarified. This study was to explore the roles of miR-424-5p/Bifunctional apoptosis regulator (BFAR) axis in glioma. Ninety-six pairs of human glioma tissues and their adjacent non-cancer tissues were collected. The levels of BFAR and miR-424-5p were detected by quantitative polymerase chain reaction (qPCR) in glioma tissues and cell lines. Moreover, the biological roles of miR-424-5p and BFAR in glioma cells were assessed. We found a miR-424-5p binding site in the 3'UTR of BFAR by using TargetScan 7.2 online database. The miR-424-5p level was dramatically decreased in glioma tissues and cell lines, and the BFAR expression was significantly increased. The BFAR expression was negatively related to the miR-424-5p level in glioma tissues. Compared to patients with high miR-424-5p levels in glioma tissues, patients with low miR-424-5p levels had significantly lower survival rate (χ² = 13.728 and P < 0.001). Compared to patients with high BFAR levels in glioma tissues, patients with low BFAR levels had significantly higher survival rate (χ² = 5.516 and P = 0.027). Furthermore, up-regulation of miR-424-5p obviously restrained glioma cells proliferation and invasion, and promoted apoptosis. Besides, knockdown of BFAR also could markedly inhibit the proliferation and invasion, and promote apoptosis. Finally, overexpression of BFAR in glioma cells partially reversed the inhibited effects of miR-424-5p mimic. Knockdown of miR-424-5p restrained glioma cell apoptosis and promoted invasion and proliferation via regulation of BFAR.

lncRNA OIP5-AS1 targets ROCK1 to promote cell proliferation and inhibit cell apoptosis through a mechanism involving miR-143-3p in cervical cancer

Opa-interacting protein 5 antisense transcript 1 (OIP5-AS1) is one kind of cytoplasmic long non-coding RNA (lncRNA), which has been demonstrated to play a critical function in multiple cancers. However, the detailed mechanism of OIP5-AS1 in the regulation of cervical cancer progression is still obscure. Here, we demonstrated that lncRNA OIP5-AS1 was upregulated in cervical cancer and was correlated with poor prognosis by bioinformatics studies. OIP5-AS1 depletion inhibited cell proliferation and promoted cell apoptosis in cervical cancer cells. Furthermore, we clarified that ROCK1 was the downstream effector of OIP5-AS1 and OIP5-AS1 acted as a molecular sponge of miR-143-3p. Finally, we verified that OIP5-AS1 exerted its function in the regulation of cervical cancer progression via interacting with miR-143-3p to regulate ROCK1 expression. Our study revealed novel mechanisms about how lncRNA OIP5-AS1 executed its function in cervical cancer and thus provided potential therapeutic targets for the disease.

miR-424-5p promotes the proliferation and metastasis of colorectal cancer by directly targeting SCN4B

BACKGROUND

Colorectal cancer (CRC) is one of the most common malignancies worldwide usually diagnosed at advanced stages which causes poor prognosis of patients. Therefore, novel diagnostic biomarkers and therapeutic targets are urgently needed.

MATERIALS AND METHODS

miR-424-5p was identified through integrated analysis of three public databases. Loss-of-function experiments in HT29 and SW480 cells and mouse xenograft models were performed to explore the regulatory role of miR-424-5p in CRC. Bioinformatics analysis was used for predicting targets of miR-424-5p and its functional and pathway enrichment analysis.

RESULTS

miR-424-5p expression was significantly upregulated in CRC tissues and cell lines and associated with prognosis of CRC patients. Experiments in vitro and in vivo showed miR-424-5p promotes CRC cell proliferation and metastasis by directly inhibiting SCN4B. Besides, CRC cells secret miR-424-5p into peripheral blood through exosomes and circulating exosomal miR-424-5p could discriminate CRC patients with early stage from healthy people with AUC value of 0.82.

CONCLUSIONS

miR-424-5p serves as an oncogene in CRC and circulating exosomal miR-424-5p is a novel potential diagnostic biomarker of CRC patients.

Direct S-Poly(T) Plus assay in quantification of microRNAs without RNA extraction and its implications in colorectal cancer biomarker studies

BACKGROUND

Advances in microRNAs (miRNAs) biomarkers have generated disease markers with potential clinical values. However, none of these published results have been applied in clinic until today. The main reason could be the lack of simple but robust miRNA measurements.

METHODS

We built up a simple but ultrasensitive RT-qPCR protocol, Direct S-Poly(T) Plus assay, for detecting miRNAs without RNA purification. In this study, the method was optimized and compared with other RNA purification-based miRNA assays, and the sensitivity was tested. Using Direct S-Poly(T) Plus method, seven potential miRNA biomarkers of colorectal cancer were validated.

RESULTS

It is possible to detect approximately 100 miRNAs with minimal plasma inputs (20 μl) and time (~ 140 min) with this approach. The sensitivity of this method was 2.7-343-fold higher than that of the stem-loop method, and comparable with S-Poly(T) plus method. 7 validated miRNA biomarkers of colorectal cancer by Direct S-Poly(T) plus assay could discriminate colorectal cancer stage I from healthy individuals, and promised satisfactory discrimination with the area under receiver operating characteristic (ROC) curve ranging from 0.79 to 0.94 (p value < 0.001).

CONCLUSIONS

This simple and robust protocol may have strong impact on the development of specific miRNAs as biomarkers in clinic.