miR‑27a promotes proliferation, migration, and invasion of colorectal cancer by targeting FAM172A and acts as a diagnostic and prognostic biomarker

Long-term severe hypoxia adaptation induces non-canonical EMT and a novel Wilms Tumor 1 (WT1) isoform

The majority of cancer deaths are caused by solid tumors, where the four most prevalent cancers (breast, lung, colorectal and prostate) account for more than 60% of all cases (1). Tumor cell heterogeneity driven by variable cancer microenvironments, such as hypoxia, is a key determinant of therapeutic outcome. We developed a novel culture protocol, termed the Long-Term Hypoxia (LTHY) time course, to recapitulate the gradual development of severe hypoxia seen in vivo to mimic conditions observed in primary tumors. Cells subjected to LTHY underwent a non-canonical epithelial to mesenchymal transition (EMT) based on miRNA and mRNA signatures as well as displayed EMT-like morphological changes. Concomitant to this, we report production of a novel truncated isoform of WT1 transcription factor (tWt1), a non-canonical EMT driver, with expression driven by a yet undescribed intronic promoter through hypoxia-responsive elements (HREs). We further demonstrated that tWt1 initiates translation from an intron-derived start codon, retains proper subcellular localization and DNA binding. A similar tWt1 is also expressed in LTHY-cultured human cancer cell lines as well as primary cancers and predicts long-term patient survival. Our study not only demonstrates the importance of culture conditions that better mimic those observed in primary cancers, especially with regards to hypoxia, but also identifies a novel isoform of WT1 which correlates with poor long-term survival in ovarian cancer.

Loss of FAM172A gene prompts cell proliferation in liver regeneration

The present study was designed to explore the function of FAM172A in liver regeneration and HCC. Mice were sacrificed after 70% partial hepatectomy (PH). RNA sequencing was performed on primary hepatocytes of WT and FAM172A-/- mice. We used HepG2 cells to construct cell lines with stably knockdown and overexpression of FAM172A. The expression of FAM172A in liver tissues was investigated by immunohistochemical staining, and we also used public database to perform survival analysis and prognostic model in HCC. Compared with WT mice after PH, normalized liver weight/body weight (LW/BW) ratio and the proliferating cell nuclear antigen (PCNA) protein level of FAM172A-/- mice elevated. The DEGs were mainly enriched in inflammatory response, tumor necrosis factor production, and wound healing. FAM172A knockdown enhanced the NFκB-TNFα and pERK-YAP1-Cyclin D1 axis. FAM172A peptide inhibited proliferation of primary hepatocytes. Moreover, the low expression of FAM172A in human HCC tissues implies a lower likelihood of survival and a valid diagnostic marker for HCC. Loss of FAM172A gene promotes cell proliferation by pERK-YAP1-Cyclin D1 and pNFκB-TNFα pathways during liver regeneration after PH. FAM172A may be a favorable diagnosis marker of HCC.

Association of lncRNA MEG3 rs941576 polymorphism, expression profile, and its related targets with the risk of obesity-related colorectal cancer: potential clinical insights

The identification of novel screening tools is imperative to empower the early detection of colorectal cancer (CRC). The influence of the long non-coding RNA maternally expressed gene 3 (MEG3) rs941576 single nucleotide polymorphism on CRC susceptibility remains uninvestigated. This research appraised MEG3 rs941576 association with the risk and clinical features of CRC and obesity-related CRC and its impact on serum MEG3 expression and its targets miR-27a/insulin-like growth factor 1 (IGF1)/IGF binding protein 3 (IGFBP3) and miR-181a/sirtuin 1 (SIRT1), along with the potential of these markers in obesity-related CRC diagnosis. 130 CRC patients (60 non-obese and 70 obese) and 120 cancer-free controls (64 non-obese and 56 obese) were enrolled. MEG3 targets were selected using bioinformatics analysis. MEG3 rs941576 was associated with magnified CRC risk in overall (OR (95% CI) 4.69(1.51-14.57), P = 0.0018) and stratified age and gender groups, but not with obesity-related CRC risk or MEG3/downstream targets' expression. Escalated miR-27a and IGFBP3 and reduced IGF1 serum levels were concomitant with MEG3 downregulation in overall CRC patients versus controls and obese versus non-obese CRC patients. Serum miR-181a and SIRT1 were upregulated in CRC patients versus controls but weren't altered in the obese versus non-obese comparison. Serum miR-181a and miR-27a were superior in overall and obesity-related CRC diagnosis, respectively; meanwhile, IGF1 was superior in distinguishing obese from non-obese CRC patients. Only serum miR-27a was associated with obesity-related CRC risk in multivariate logistic analysis. Among overall CRC patients, MEG3 rs941576 was associated with lymph node (LN) metastasis and tumor stage, serum MEG3 was negatively correlated with tumor stage, while SIRT1 was correlated with the anatomical site. Significant correlations were recorded between MEG3 and anatomical site, SIRT1 and tumor stage, and miR-27a/IGFBP3 and LN metastasis among obese CRC patients, while IGF1 was correlated with tumor stage and LN metastasis among non-obese CRC patients. Conclusively, this study advocates MEG3 rs941576 as a novel genetic marker of CRC susceptibility and prognosis. Our findings accentuate circulating MEG3/miR-27a/IGF1/IGFBP3, especially miR-27a as valuable markers for the early detection of obesity-related CRC. This axis along with SIRT1 could benefit obesity-related CRC prognosis.

Construction of an immune predictive model and identification of TRIP6 as a prognostic marker and therapeutic target of CRC by integration of single-cell and bulk RNA-seq data

BACKGROUND

Investigations elucidating the complex immunological mechanisms involved in colorectal cancer (CRC) and accurately predicting patient outcomes via bulk RNA-Seq analysis have been notably limited. This study aimed to identify the immune status of CRC patients, construct a prognostic model, and identify prognostic signatures via bulk RNA sequencing (RNA-seq) and single-cell RNA-seq (scRNA-seq).

METHODS

The scRNA-seq data of CRC were downloaded from Gene Expression Omnibus (GEO). The UCSC Xena database was used to obtain bulk RNA-seq data. Differentially expressed gene (DEG), functional enrichment, and random forest analyses were conducted in order to identify core genes associated with colorectal cancer (CRC) that were relevant to prognosis. A molecular immune prediction model was developed using logistic regression after screening features using the least absolute shrinkage and selection operator (LASSO). The differences in immune cell infiltration, mutation, chemotherapeutic drug sensitivity, cellular senescence, and communication between patients who were at high and low risk of CRC according to the predictive model were investigated. The prognostic genes that were closely associated with CRC were identified by random survival forest (RSF) analysis. The expression levels and clinical significance of the hub genes were analyzed in vitro. The LoVo cell line was employed to ascertain the biological role of thyroid hormone receptor-interacting protein 6 (TRIP6).

RESULTS

A total of seven main cell subtypes were identified by scRNA-seq analysis. A molecular immune predictive model was constructed based on the risk scores. The risk score was significantly associated with OS, stage, mutation burden, immune cell infiltration, response to immunotherapy, key pathways, and cell-cell communication. The functions of the six hub genes were determined and further utilized to establish a regulatory network. Our findings unequivocally confirmed that TRIP6 upregulation was verified in the CRC samples. After knocking down TRIP6, cell proliferation, migration, and invasion of LoVo cells were inhibited, and apoptosis was promoted.

CONCLUSIONS

The molecular predictive model reliably distinguished the immune status of CRC patients. We further revealed that TRIP6 may act as an oncogene in CRC, making it a promising candidate for targeted therapy and as a prognostic marker for CRC.

m6A‑mediated LINC02038 inhibits colorectal cancer progression via regulation of the FAM172A/PI3K/AKT pathway via competitive binding with miR‑552‑5p

Long noncoding RNAs (lncRNAs) are a type of regulatory molecule with potential roles in the development of several different malignancies. However, the underlying mechanisms of lncRNAs in colorectal cancer (CRC) are incompletely understood. The present study investigated the molecular mechanism of LINC02038 in CRC. LINC02038 expression was decreased in CRC tissues compared to the para‑cancerous tissues and LINC02038 overexpression markedly reduced the proliferation, vitality, migration and invasive ability and greatly accelerated apoptosis of colorectal cancer cells. Bioinformatics examination indicated that LINC02038 may have targeted microRNA (miR)‑552‑5p. RNA immunoprecipitation and luciferase reporter assays showed that LINC02038 served as a sponge for miR‑552‑5p, hindering target gene FAM172A of miR‑552‑5p degradation. Moreover, methylated RNA immunoprecipitation (MeRIP)‑qualitative PCR assays revealed that YTHDF2 could identify and regulate the METTL3‑mediated LINC02038 N6‑methyladenosine (m6A) modification and increase its degradation, thereby promoting CRC progression via the PI3K/AKT pathway. Based on the CRC clinical specimens, it was shown that LINC02038 was negatively associated with lymphatic metastasis and distant metastasis. These results revealed that m6A/LINC02038/miR‑552‑5p/FAM172A may be a novel anti‑tumor axis and LINC02038 may serve as a biomarker and treatment option for colorectal cancer.

M6A Promotes Colorectal Cancer Progression via Regulating the miR-27a-3p/BTG2 Pathway

Long noncoding (lnc) RNAs regulate cancer progression. However, the importance of lncRNAs and how they are regulated in colorectal cancer (CRC) are unclear. We aim to evaluate the function of lncRNA ADAMTS9-AS2 in CRC and its fundamental mechanism. Levels of ADAMTS9-AS2, miR-27a-3p, and B-cell translocation gene 2 (BTG2) were measured by qPCR. Cell viability was analyzed by CCK-8 and colony formation. Migration and invasion were tested by transwell assay. The interactions among ADAMTS9-AS2, miR-27a-3p, BTG2, and YTHDF2 were analyzed by luciferase test, immunoblotting, RNA pull-down, or RNA immunoprecipitation (RIP). An animal model was adopted to assess ADAMTS9-AS2's function. Overexpressing ADAMTS9-AS2 inhibited cell migration, invasion, colony formation capacity, and proliferation in vitro. The direct targeting of miR-27a-3p by ADAMTS9-AS2 abrogated the latter's effect in CRC cells. BTG2 was identified a target of miR-27a-3p, and silencing BTG2 weakened miR-27a-3p's effect. Knocking down ADAMTS9-AS2 abolished sh-YTHDF2's inhibitory effect on cell proliferation and invasion. Finally, overexpressing ADAMTS9-AS2 restrained xenograft growth. M6A reader YTHDF2-mediated degradation of ADAMTS9-AS2 promotes colon carcinogenesis via miR-27a-3p/BTG2 axis.

Association of Androgenic Regulation and MicroRNAs in Acinar Adenocarcinoma of Prostate

Background: Prostate cancer represents 3.8% of cancer deaths worldwide. For most prostate cancer cells to grow, androgens need to bind to a cellular protein called the androgen receptor (AR). This study aims to demonstrate the expression of five microRNAs (miRs) and its influence on the AR formation in patients from the northern region of Brazil. Material and Methods: Eighty-four tissue samples were investigated, including nodular prostatic hyperplasia (NPH) and acinar prostatic adenocarcinoma (CaP). Five miRs (27a-3p, 124, 130a, 488-3p, and 506) were quantified using the TaqMan^® Real Time PCR method and AR was measured using Western blotting. Results: Levels of miRs 124, 130a, 488-3p, and 506 were higher in NPH samples. Conversely, in the CaP cases, higher levels of miR 27a-3p and AR were observed. Conclusion: In the future, these microRNAs may be tested as markers of CaP at the serum level. The relative expression of AR was 20% higher in patients with prostate cancer, which suggests its potential as a biomarker for prostate malignancy.

microRNAs: Small molecules with a large impact on colorectal cancer

Colorectal cancer (CRC) accounts for one of the main cancer-related mortality and morbidity worldwide. The molecular mechanisms of CRC development have been broadly investigated and, over the last decade, it has become evident that aberrant transcription of microRNAs (miRNAs), a class of small, noncoding RNA molecules, has a significant role in the inception and promotion of CRC. In the involved tissues of CRC, the transcription profile of miRNAs is modulated, and their expression templates are related with prognosis, diagnosis, and treatment outcomes. Here, in the current review, we attempted to discuss the latest information regarding the aberrantly expressed miRNAs in CRC and the advantages of utilizing miRNAs as biomarkers for early diagnosis and prognosis of CRC as well as potential therapeutic application. The effect of miRNAs involved in various signaling pathways, primarily p53, EGFR, Wnt, and TGF-β pathways, was clarified.

FAM172A Deletion May Enhance Hepatic Steatosis by Promoting ER Stress

BACKGROUND

Endoplasmic reticulum (ER) stress is one of the major causes to the pathogenesis of nonalcoholic fatty liver disease (NAFLD). Our previous study showed that maintains the homeostasis of ER could effectively alleviate NAFLD. In this study, we found that the loss of FAM172A increased ER stress.

AIMS

The aims of this study were to explore whether FAM172A could improve NAFLD by inhibiting ER stress.

METHODS

The expression levels of FAM172A and ER stress were detected by western blot. The method of immunofluorescence was used to determine FAM172A location. The interacted proteins of FAM172A were identified by immunocoprecipitation. The methods of MTS and caspase-3/7 activity were taken to confirm the effect of FAM172A on cell viability and proliferation. The expression levels of inflammation were detected by qPCR.

RESULTS

We confirmed that FAM172A might alleviate NAFLD through inhibiting ER stress. Loss of FAM172A increased the expressions of ATF6, peIF2α, but decreased the expression of IRE1α. Then, it was shown that FAM172A located in ER and FAM172A directly interacted with ATF6 and peIF2α and IRE1α. More importantly, the binding of FAM172A and eIF2a in tunicamycin-treated group increased significantly compared with the control group. However, the binding of FAM172A and ATF6 or IRE1α did not change. Next, we found that the lack of FAM172A could produce more apoptosis and inflammation.

CONCLUSIONS

Our results suggest that FAM172A improve steatosis by alleviating ER stress.

Deletion of Fam172a accelerates advanced atherosclerosis and induces plaque instability

BACKGROUND AND AIMS

Vascular smooth muscle cells (VSMCs) play a critical role in atherosclerosis. The family with sequence similarity 172, member A (FAM172A) is a novel protein and its role in atherosclerosis has not been explored so far. Therefore, our aim is to investigate whether FAM172A affects atheroprogression through VSMCs and its possible mechanism.

METHODS

Fam172a^-/- mice were generated using CRISPR/Cas9 technology. Fam172a^-/- and Apoe^-/- double knockout (Fam172a^-/-/Apoe^-/-) mice and their littermates (Fam172a^+/+/Apoe^-/-) were fed with a Western diet for 18 weeks to induce advanced atherosclerotic lesions. The role and mechanism of Fam172a in phenotypic switching, proliferation and migration of VSMCs were investigated through in vivo and in vitro experiments.

RESULTS

Compared with Fam172a^+/+/Apoe^-/- mice, Fam172a^-/-/Apoe^-/- mice showed increased atherosclerotic lesion size and plaque instability such as increased necrotic core area and decreased fiber deposition. Additionally, knockout of Fam172a promoted expression of CD68 and KLF4 and decreased expression of α-SMA and SM22α in atherosclerotic lesions. Furthermore, overexpression of Fam172a promoted Movas cells proliferation and migration, increased expression of α-SMA and SM22α and decreased expression of KLF4. Meanwhile, knockdown of Fam172a in Movas cells and deletion of Fam172a in VSMCs from Fam172a^-/-/Apoe^-/- mice showed opposite phenotypes. Similar phenotypes were also observed in human aortic smooth muscle cells.

CONCLUSIONS

Our results provide the first direct evidence that Fam172a has a protective role in advanced atherosclerosis by increasing atherosclerotic plaque stability and inhibiting transition of VSMCs from contractile to synthetic phenotype, which may be through KLF4-dependent pathway.

miRNA Clusters with Up-Regulated Expression in Colorectal Cancer

Simple Summary

As miRNAs show the capacity to be used as CRC biomarkers, we analysed experimentally validated data about frequently up-regulated miRNA clusters in CRC tissue. We identified 15 clusters that showed increased expression in CRC: miR-106a/363, miR-106b/93/25, miR-17/92a-1, miR-181a-1/181b-1, miR-181a-2/181b-2, miR-181c/181d, miR-183/96/182, miR-191/425, miR-200c/141, miR-203a/203b, miR-222/221, mir-23a/27a/24-2, mir-29b-1/29a, mir-301b/130b and mir-452/224. Cluster positions in the genome are intronic or intergenic. Most clusters are regulated by several transcription factors, and by long non-coding RNAs. In some cases, co-expression of miRNA with other cluster members or host gene has been proven. miRNA expression patterns in cancer tissue, blood and faeces were compared. The members of the selected clusters target 181 genes. Their functions and corresponding pathways were revealed with the use of Panther analysis. Clusters miR-17/92a-1, miR-106a/363, miR-106b/93/25 and miR-183/96/182 showed the strongest association with metastasis occurrence and poor patient survival, implicating them as the most promising targets of translational research.

Abstract

Colorectal cancer (CRC) is one of the most common malignancies in Europe and North America. Early diagnosis is a key feature of efficient CRC treatment. As miRNAs can be used as CRC biomarkers, the aim of the present study was to analyse experimentally validated data on frequently up-regulated miRNA clusters in CRC tissue and investigate their members with respect to clinicopathological characteristics of patients. Based on available data, 15 up-regulated clusters, miR-106a/363, miR-106b/93/25, miR-17/92a-1, miR-181a-1/181b-1, miR-181a-2/181b-2, miR-181c/181d, miR-183/96/182, miR-191/425, miR-200c/141, miR-203a/203b, miR-222/221, mir-23a/27a/24-2, mir-29b-1/29a, mir-301b/130b and mir-452/224, were selected. The positions of such clusters in the genome can be intronic or intergenic. Most clusters are regulated by several transcription factors, and miRNAs are also sponged by specific long non-coding RNAs. In some cases, co-expression of miRNA with other cluster members or host gene has been proven. miRNA expression patterns in cancer tissue, blood and faeces were compared. Based on experimental evidence, 181 target genes of selected clusters were identified. Panther analysis was used to reveal the functions of the target genes and their corresponding pathways. Clusters miR-17/92a-1, miR-106a/363, miR-106b/93/25 and miR-183/96/182 showed the strongest association with metastasis occurrence and poor patient survival, implicating them as the most promising targets of translational research.

Plasma Extracellular Vesicle miRNAs Can Identify Lung Cancer, Current Smoking Status, and Stable COPD

Lung cancer remains the leading cause of cancer related mortality worldwide. We aimed to test whether a simple blood biomarker (extracellular vesicle miRNAs) can discriminate between cases with and without lung cancer.

METHODS

plasma extracellular vesicles (EVs) were isolated from four cohorts (n = 20 in each): healthy non-smokers, healthy smokers, lung cancer, and stable COPD participants. EV miRNA expression was evaluated using the miRCURY LNA miRNA Serum/Plasma assay for 179 specific targets. Significantly dysregulated miRNAs were assessed for discriminatory power using ROC curve analysis.

RESULTS

15 miRNAs were differentially expressed between lung cancer and healthy non-smoking participants, with the greatest single miRNA being miR-205-5p (AUC 0.850), improving to AUC 0.993 in combination with miR-199a-5p. Moreover, 26 miRNAs were significantly dysregulated between lung cancer and healthy smoking participants, with the greatest single miRNA being miR-497-5p (AUC 0.873), improving to AUC 0.953 in combination with miR-22-5p; 14 miRNAs were significantly dysregulated between lung cancer and stable COPD participants, with the greatest single miRNA being miR-27a-3p (AUC 0.803), with two other miRNAs (miR-106b-3p and miR-361-5p) further improving discriminatory power (AUC 0.870).

CONCLUSION

this case control study suggests miRNAs in EVs from plasma holds key biological information specific for lung cancer and warrants further prospective assessment.

Exosomal microRNAs and other non-coding RNAs as colorectal cancer biomarkers: a review

The circulating human transcriptome, which includes both coding and non-coding RNA (ncRNA) molecules, represents a rich source of potential biomarkers for colorectal cancer (CRC) that has only recently been explored. In particular, the release of RNA-containing extracellular vesicles (EVs), in a multitude of different in vitro cell systems and in a variety of body fluids, has attracted wide interest. The role of RNA species in EVs is still not fully understood, but their capacity to act as a form of distant communication between cells and their higher abundance in association with cancer demonstrated their relevance. In this review, we report the evidence from both in vitro and human studies on microRNAs (miRNAs) and other ncRNA profiles analysed in EVs in relation to CRC as diagnostic, prognostic and predictive markers. The studies so far highlighted that, in exosomes, the most studied category of EVs, several miRNAs are able to accurately discriminate CRC cases from controls as well as to describe the progression of the disease and its prognosis. Most of the time, the in vitro findings support the miRNA profiles detected in human exosomes. The expression profiles measured in exosomes and other EVs differ and, interestingly, there is a variability of expression also among different subsets of exosomes according to their proteic profile. On the other hand, evidence is still limited for what concerns exosome miRNAs as early diagnostic and predictive markers of treatment. Several other ncRNAs that are carried by exosomes, mostly long ncRNAs and circular RNAs, seem also to be dysregulated in CRC. Besides various technical challenges, such as the standardisation of EVs isolation methods and the optimisation of methodologies to characterise the whole spectrum of RNA molecules in exosomes, further studies are needed in order to elucidate their relevance as CRC markers.

Differential Expression of miR-21, miR-23a, and miR-27a, and Their Diagnostic Significance in Egyptian Colorectal Cancer Patients

Background: Colorectal cancer (CRC) rates are affected by genetics, ethnicity, and environmental factors; it is considered one of the most aggressive human malignancies with high mortality and morbidity rates worldwide due, in part, to its asymptomatic nature during the early stages of disease. Objective: Owing to the impact of microRNA (miRNA) dysregulation on CRC development and progression, this study was conducted to explore the expression levels of mir-21, -23a, and -27a in the sera and tissues of Egyptian CRC patients and to evaluate their diagnostic efficacy based on circulating levels. Methods: In the test phase, the relative expression levels of the studied miRNAs were evaluated in the sera of 70 participants (35 CRC patients and 35 healthy controls) using quantitative real-time-polymerase chain reaction and to verify their diagnostic value. The exploratory phase was designed to validate the tumor-derived trait by comparing the miRNA levels in the cancerous and adjacent noncancerous tissues. Results: The relative expression levels of the studied miRNAs were significantly upregulated in both serum and tumor tissues of the patients compared to their corresponding controls. In addition, significant positive correlations were found between the relative expression levels of the studied miRNAs in serum samples and their levels in the matched CRC tissues. The serum expression levels of mir-21 and -23a were more predictive of CRC than mir-27a. Conclusion: Circulating mir-21, -23a, and -27a expression levels appear to be valuable diagnostic biomarkers for CRC, especially when combined.

The association of miR-27a rs895819 polymorphism with colorectal cancer risk in Chinese population

Background

Besides environment and living habits, such as a sedentary lifestyle, smoking and drinking, genetic variation also plays an important role in the development of colorectal cancer (CRC). This study was aimed to investigate the role of miR‑27a rs895819 polymorphism on CRC risk in Chinese population.

Methods

In a case‐control study including 208 CRC and 312 age‐ and gender‐matched healthy control subjects, the rs895819 polymorphism was genotyped using the TaqMan allelic discrimination assay. Furthermore, a pooled analysis based on eligible studies was performed by using the STATA software.

Results

Logistic regression analysis showed that the rs895819 polymorphism was not associated with CRC risk. However, a pooled analysis based on five studies from Chinese population showed a statistically significant association between the rs895819 polymorphism and CRC risk (GG vs AA: OR = 1.56, 95% CI = 1.27‐1.92, Pz < .01; (AG + GG) vs AA: OR = 1.14, 95% CI = 1.01‐1.30, Pz = .04; GG vs (AG + AA): OR = 1.54, 95% CI = 1.27‐1.88, Pz < .01; G vs A: OR = 1.20, 95% CI = 1.09‐1.33, Pz < .01).

Conclusion

Our study suggests that miR‑27a rs895819 polymorphism plays an important role in CRC risk in Chinese population and may serve as a valuable biomarker for predicting an individual's susceptibility to CRC.

3D Cell Culture-Based Global miRNA Expression Analysis Reveals miR-142-5p as a Theranostic Biomarker of Rectal Cancer Following Neoadjuvant Long-Course Treatment

Altered expression of miRNAs in tumor tissue encourages the translation of this specific molecular pattern into clinical practice. However, the establishment of a selective biomarker signature for many tumor types remains an inextricable challenge. For this purpose, a preclinical experimental design, which could maintain a fast and sensitive discovery of potential biomarkers, is in demand. The present study suggests that the approach of 3D cell cultures as a preclinical cancer model that is characterized to mimic a natural tumor environment maintained in solid tumors could successfully be employed for the biomarker discovery and validation. Subsequently, in this study, we investigated an environment-dependent miRNA expression changes in colorectal adenocarcinoma DLD1 and HT29 cell lines using next-generation sequencing (NGS) technology. We detected a subset of 16 miRNAs differentially expressed in both cell lines cultivated in multicellular spheroids compared to expression levels in cells grown in 2D. Furthermore, results of in silico miRNA target analysis showed that miRNAs, which were differentially expressed in both cell lines grown in MCS, are involved in the regulation of molecular mechanisms implicated in cell adhesion, cell-ECM interaction, and gap junction pathways. In addition, integrins and platelet-derived growth factor receptors were determined to be the most significant target genes of deregulated miRNAs, which was concordant with the environment-dependent gene expression changes validated by RT-qPCR. Our results revealed that 3D microenvironment-dependent deregulation of miRNA expression in CRC cells potentially triggers essential molecular mechanisms predominantly including the regulation of cell adhesion, cell-cell, and cell-ECM interactions important in CRC initiation and development. Finally, we demonstrated increased levels of selected miR-142-5p in rectum tumor tissue samples after neoadjuvant long course treatment compared to miR-142-5p expression levels in tumor biopsy samples collected before the therapy. Remarkably, the elevation of miR-142-5p expression remained in tumor samples compared to adjacent normal rectum tissue as well. Therefore, the current study provides valuable insights into the molecular miRNA machinery of CRC and proposes a potential miRNA signature for the assessment of CRC in further clinical research.

FAM172A inhibits EMT in pancreatic cancer via ERK-MAPK signaling

FAM172A, as a newly discovered gene, is little known in cancer development, especially in pancreatic cancer (PC). We investigated the potential role and molecular mechanism of FAM172A in epithelial to mesenchymal transition (EMT) in both human clinical samples and PC cells. FAM172A was downregulated in human PC tissues compared with that in non-cancerous pancreas cells by immunohistochemistry and qRT-PCR. FAM172A expression was negatively associated with tumor size (P=0.015), T stage (P=0.006), lymph node metastasis (P=0.028) and the worst prognosis of PC patients (P=0.004). Meanwhile, a positive relationship between FAM172A and E-cadherin (E-cad) (r=0.381, P=0.002) was observed in clinical samples, which contributed to the better prognosis of PC patients (P=0.014). FAM172A silencing induced EMT in both AsPC-1 and BxPC-3 cells, including inducing the increase of Vimentin, MMP9 and pERK and the decrease of E-cad and β-catenin expression, stimulating EMT-like cell morphology and enhancing cell invasion and migration in PC cells. However, MEK1 inhibitor PD98059 reversed FAM172A silencing-enhanced EMT in PC cells. We conclude that FAM172A inhibits EMT of PC cells via ERK-MAPK signaling.

Interactions among lncRNAs, miRNAs and mRNA in colorectal cancer

Long non-coding RNAs (lncRNAs) are longer than 200 nts non-coding transcripts and have recently emerged as one of the largest and significantly diverse RNA families whereas microRNAs (miRNAs) are highly conserved short single-stranded ncRNAs (∼18-22 nucleotides). As families of small and long evolutionarily conserved ncRNAs, lncRNAs activate and repress genes via a variety of mechanisms at both transcriptional and translational levels, while miRNAs regulate protein-coding gene expression mainly through mRNA degradation or silencing, These ncRNAs have been proved to be involved in multiple biological functions, such as proliferation, differentiation, migration, angiogenesis and apoptosis. Today, while majority of studies have focused on defining the regulatory functions of lncRNAs and miRNAs, limited information have now available for the mutual regulations of lncRNAs, miRNAs and mRNA. Thus, the underlying molecular mechanisms, in particularly the interactions among lncRNAs, miRNAs and mRNA in development, growth, metastasis and therapeutic potential of cancer still remain obscure. Colorectal cancer (CRC) is known as the third most common and fourth leading cancer death worldwide. Increasing evidence showed the close correlations among aberrant expressions of lncRNAs, miRNAs and the occurrence, development of CRC. This review summarize the potential links among these RNAs in following three areas: 1, The biogenesis and roles of miRNAs in CRC; 2, The biogenesis and functions of lncRNAs in CRC; 3, The interactions among lncRNAs, miRNAs and mRNA in tumorigensis, growth, progression, EMT formation, chemoradiotherapy resistance, and therapeutic potential in CRC. We believe that identifying diverging lncRNAs, miRNAs and relevant genes, their interactions and complex molecular regulatory networks will provide important clues for understanding the mechanism and developing novel diagnostic and therapeutic strategies for CRC. Further efforts are warranted to bring the promise of regulating their activities into clinical utilities.

miR‑27a promotes human breast cancer cell migration by inducing EMT in a FBXW7‑dependent manner

Increasingly, evidence has revealed that aberrant microRNA (miRNA) expression is involved in breast cancer carcinogenesis and further progression, including metastasis. miRNA (miR)‑27a was previously identified to be abnormally expressed and to serve pro‑oncogenic functions in multiple human cancer types, including breast cancer. However, its functions and underlying mechanisms in breast cancer remain poorly understood. In the present study, it was demonstrated that miR‑27a was significantly upregulated in breast cancer tissues and cell lines compared with their normal counterparts. Overexpression of miR‑27a resulted in enhanced cell migration by inducing epithelial‑to‑mesenchymal transition, while its knockdown effectively reversed these cellular events. The present study additionally confirmed for the first time, to the best of our knowledge, that F‑box and WD repeat domain containing 7 (FBXW7) is a downstream target gene of miR‑27a in human breast cancer cells. FBXW7 is underexpressed in breast cancer tissues and cell lines, and is an independent positive factor for the overall survival rate of patients with breast cancer. Notably, the ectopic expression of FBXW7 may effectively suppress the epithelial‑to‑mesenchymal transition and migratory activity of breast cancer cells, in addition to reversing the cell migration mediated by miR‑27a. Altogether, the results of the present study indicated the important function of miR‑27a in regulating the metastasis of breast cancer in a FBXW7‑dependent manner, and provide evidence for the potential application of miR‑27a in breast cancer therapy.

Circulating Exosomal miR-27a and miR-130a Act as Novel Diagnostic and Prognostic Biomarkers of Colorectal Cancer

Background: Colorectal cancer is one of the most common cancers worldwide usually is associated with poor prognosis due to the advanced stage when diagnosed. This study aimed to investigate whether specific circulating exosomal miRNAs could act as biomarkers for early diagnosis of colorectal cancer.Methods: A total of 369 peripheral blood samples were included in this study. In the discovery phase, circulating exosomal miR-27a and miR-130a were selected after synthetical analysis of two GEO datasets and TCGA database. The differential expression and diagnostic utility of miR-27a and miR-130a panel were validated using qRT-PCR and ROC curve analysis in subsequent training phase, validation phase, and external validation phase. The prognosis of circulating exosomal miR-27a and miR-130a were investigated using the Kaplan-Meier method.Results: The expression of exosomal miR-27a and miR-130a in plasma significantly increased in colorectal cancer. The area under ROC curves (AUC) of miR-27a (miR-130a) were 0.773 (0.742) in the training phase, 0.82 (0.787) in the validation phase, and 0.746 (0.697) in the external validation phase. The combination of two miRNAs presented higher diagnostic utility for colorectal cancer (AUCs = 0.846, 0.898, and 0.801 for the training, validation, and external validation phases, respectively). Patients with colorectal cancer with high expression of circulating exosomal miR-27a or miR-130a underwent poorer prognosis.Conclusions: We identified a circulating exosomal miRNAs panel for the detection of colorectal cancer.Impact: The exosomal miR-27a and miR-130a panel in plasma may act as a noninvasive biomarker for early detection and predicting prognosis of colorectal cancer. Cancer Epidemiol Biomarkers Prev; 27(7); 746-54. ©2018 AACR.

Comparative miRNA Expression Profile Analysis of Squamous Cell Carcinoma and Peritumoral Mucosa from the Meso- and Hypopharynx

BACKGROUND/AIM

The role of microRNAs (miRNA) in carcinogenesis is related to their genome-regulatory function. The aim of the present study was to identify and compare miRNA expression signatures of meso- and hypopharynx squamous cell cancers in consideration of the cancer field hypothesis.

PATIENTS AND METHODS

Thirteen snap-frozen biopsy series of tumors and peritumoral tissues from the meso- and hypopharynx were analyzed regarding their miRNA expression with quantitative real-time polymerase chain reaction (qRT-PCR).

RESULTS

Significant miRNA expression changes of miR-21, -27a, -34a, -143 and -146a were found in peritumoral tissues that were dependent from the tumor location and the distance from the primary tumor site.

CONCLUSION

miRNA expression analysis was found to be appropriate for molecular segregation of tumor location and peritumoral tissue segments, and appears to be a promising marker for cancer field characterization.