Low expression of microRNA-30c promotes invasion by inducing epithelial mesenchymal transition in non-small cell lung cancer

Targeting vimentin: a multifaceted approach to combatting cancer metastasis and drug resistance

This comprehensive review explores vimentin as a pivotal therapeutic target in cancer treatment, with a primary focus on mitigating metastasis and overcoming drug resistance. Vimentin, a key player in cancer progression, is intricately involved in processes such as epithelial-to-mesenchymal transition (EMT) and resistance mechanisms to standard cancer therapies. The review delves into diverse vimentin inhibition strategies. Precision tools, including antibodies and nanobodies, selectively neutralize vimentin's pro-tumorigenic effects. DNA and RNA aptamers disrupt vimentin-associated signaling pathways through their adaptable binding properties. Innovative approaches, such as vimentin-targeted vaccines and microRNAs (miRNAs), harness the immune system and post-transcriptional regulation to combat vimentin-expressing cancer cells. By dissecting vimentin inhibition strategies across these categories, this review provides a comprehensive overview of anti-vimentin therapeutics in cancer treatment. It underscores the growing recognition of vimentin as a pivotal therapeutic target in cancer and presents a diverse array of inhibitors, including antibodies, nanobodies, DNA and RNA aptamers, vaccines, and miRNAs. These multifaceted approaches hold substantial promise for tackling metastasis and overcoming drug resistance, collectively presenting new avenues for enhanced cancer therapy.

Sex differences in the tumor promoting effects of tobacco smoke in a cRaf transgenic lung cancer disease model

Tobacco smoke (TS) is the leading cause for lung cancer (LC), and female smokers are at a greater risk for LC. Yet, the underlying causes are unknown. We performed whole genome scans in TS exposed wild type and histologically characterized tumor lesions of cRaf transgenic mice. We constructed miRNA-gene and transcription factor-miRNA/gene regulatory networks and determined sex-specific gene regulations by evaluating hormone receptor activities. We validated the findings from TS exposed cRaf mice in a large cohort of smoking and never-smoking LC patients. When compared to males, TS prompted a sevenfold increase in tumor multiplicity in cRaf females. Genome-wide scans of tumor lesions identified 161 and 53 genes and miRNAs, which code for EGFR/MAPK signaling, cell proliferation, oncomirs and oncogenes, and 50% of DEGs code for immune response and tumor evasion. Outstandingly, in transgenic males, TS elicited upregulation of 20 tumor suppressors, some of which are the targets of the androgen and estrogen receptor. Conversely, in females, 18 tumor suppressors were downregulated, and five were specifically repressed by the estrogen receptor. We found TS to perturb the circadian clock in a sex-specific manner and identified a female-specific regulatory loop that consisted of the estrogen receptor, miR-22-3p and circadian genes to support LC growth. Finally, we confirmed sex-dependent tumor promoting effects of TS in a large cohort of LC patients. Our study highlights the sex-dependent genomic responses to TS and the interplay of circadian clock genes and hormone receptors in the regulation of oncogenes and oncomirs in LC growth.

Identification of miR-30c-5p microRNA in Serum as a Candidate Biomarker to Diagnose Endometriosis

The diagnosis of endometriosis by laparoscopy is delayed until advanced stages. In recent years, microRNAs have emerged as novel biomarkers for different diseases. These molecules are small non-coding RNA sequences involved in the regulation of gene expression and can be detected in peripheral blood. Our aim was to identify candidate serum microRNAs associated with endometriosis and their role as minimally invasive biomarkers. Serum samples were obtained from 159 women, of whom 77 were diagnosed with endometriosis by laparoscopy and 82 were healthy women. First, a preliminary study identified 29 differentially expressed microRNAs between the two study groups. Next, nine of the differentially expressed microRNAs in the preliminary analysis were evaluated in a new cohort of 67 women with endometriosis and 72 healthy women. Upon validation by quantitative real-time PCR technique, the circulating level of miR-30c-5p was significantly higher in the endometriosis group compared with the healthy women group. The area under the curve value of miR-30c-5p was 0.8437, demonstrating its diagnostic potential even when serum samples registered an acceptable limit of hemolysis. Dysregulation of this microRNA was associated with molecular pathways related to cancer and neuronal processes. We concluded that miR-30c-5p is a potential minimally invasive biomarker of endometriosis, with higher expression in the group of women with endometriosis diagnosed by laparoscopy.

Sex disparities in non-small cell lung cancer: mechanistic insights from a cRaf transgenic disease model

BACKGROUND

Women are at greater risk of developing non-small cell lung cancer (NSCLC), yet the underlying causes remain unclear.

METHODS

We performed whole genome scans in lung tumours of cRaf transgenic mice and identified miRNA, transcription factor and hormone receptor dependent gene regulations. We confirmed hormone receptors by immunohistochemistry and constructed regulatory gene networks by considering experimentally validated miRNA-gene and transcription factor-miRNA/gene targets. Bioinformatics, genomic foot-printing and gene enrichment analysis established sex-specific circuits of lung tumour growth. Translational research involved a large cohort of NSCLC patients. We evaluated commonalities in sex-specific NSCLC gene regulations between mice and humans and determined their prognostic value in Kaplan-Meier survival statistics and COX proportional hazard regression analysis.

FINDINGS

Overexpression of the cRaf kinase elicited an extraordinary 8-fold increase in tumour growth among females, and nearly 70% of the 112 differentially expressed genes (DEGs) were female specific. We identified oncogenes, oncomirs, tumour suppressors, cell cycle regulators and MAPK/EGFR signalling molecules, which prompted sex-based differences in NSCLC, and we deciphered a regulatory gene-network, which protected males from accelerated tumour growth. Strikingly, 41% of DEGs are targets of hormone receptors, and the majority (85%) are oestrogen receptor (ER) dependent. We confirmed the role of ER in a large cohort of NSCLC patients and validated 40% of DEGs induced by cRaf in clinical tumour samples.

INTERPRETATION

We report the molecular wiring that prompted sex disparities in tumour growth. This allowed us to propose the development of molecular targeted therapies by jointly blocking ER, CDK1 and arginase 2 in NSCLC.

FUNDING

We gratefully acknowledge the financial support of the Lower Saxony Ministry of Culture and Sciences and Volkswagen Foundation, Germany to JB (25A.5-7251-99-3/00) and of the Chinese Scholarship Council to SZ (202008080022). This publication is funded by the Deutsche Forschungsgemeinschaft (DFG) as part of the "Open Access Publikationskosten" program.

HCV Proteins Modulate the Host Cell miRNA Expression Contributing to Hepatitis C Pathogenesis and Hepatocellular Carcinoma Development

Simple Summary

According to the last estimate by the World Health Organization (WHO), more than 71 million individuals have chronic hepatitis C worldwide. The persistence of HCV infection leads to chronic hepatitis, which can evolve into liver cirrhosis and ultimately into hepatocellular carcinoma (HCC). Although the pathogenic mechanisms are not fully understood, it is well established that an interplay between host cell factors, including microRNAs (miRNA), and viral components exist in all the phases of the viral infection and replication. Those interactions establish a complex equilibrium between host cells and HCV and participate in multiple mechanisms characterizing hepatitis C pathogenesis. The present review aims to describe the role of HCV structural and non-structural proteins in the modulation of cellular miRNA during HCV infection and pathogenesis.

Abstract

Hepatitis C virus (HCV) genome encodes for one long polyprotein that is processed by cellular and viral proteases to generate 10 polypeptides. The viral structural proteins include the core protein, and the envelope glycoproteins E1 and E2, present at the surface of HCV particles. Non-structural (NS) proteins consist of NS1, NS2, NS3, NS4A, NS4B, NS5a, and NS5b and have a variable function in HCV RNA replication and particle assembly. Recent findings evidenced the capacity of HCV virus to modulate host cell factors to create a favorable environment for replication. Indeed, increasing evidence has indicated that the presence of HCV is significantly associated with aberrant miRNA expression in host cells, and HCV structural and non-structural proteins may be responsible for these alterations. In this review, we summarize the recent findings on the role of HCV structural and non-structural proteins in the modulation of host cell miRNAs, with a focus on the molecular mechanisms responsible for the cell re-programming involved in viral replication, immune system escape, as well as the oncogenic process. In this regard, structural and non-structural proteins have been shown to modulate the expression of several onco-miRNAs or tumor suppressor miRNAs.

Association of miRNA 30c, miRNA 181a and miRNA 570 SNPs with Bladder Cancer Risk in North Indian Population: A Pilot Study

miRNA play role in post transcriptional regulation of genes and serves a range of biological functions such as initiation, development, metastasis etc. which are also hallmarks of cancer. Hence, we evaluated miRNA 181a, miRNA 30c and miRNA 570 in bladder cancer risk association among North Indians. miRNA 570 C/G (rs4143815), miRNA 30c A/G (rs928508) and miRNA 181a C/T (rs12537) single nucleotide polymorphisms (SNPs) were genotyped by allelic discrimination TaqMan assay in 100 bladder cancer (BC) patients and 100 healthy controls. No significant difference was found in the genotype frequencies of the candidate SNPs among cases and controls. However, combined effect of miRNA 570-miRNA 30c (CG + AA) p = 0.005, OR = 0.223, 95% CI and miRNA 570-miRNA 181a (CG + CC) p = 0.003, OR = 0.169, 95% CI conferred association with no risk of BC. miRNA 181a C/T (rs12537), miRNA 30c A/G (rs928508) and miRNA 570 C/G (rs4143815) should be further validated in large sample size to be used as a risk predictor for bladder cancer among North Indians.

Autophagy-mediating microRNAs in cancer chemoresistance

Chemoresistance is a complex phenomenon responsible for failure in response to chemotherapy agents and more than 90% of deaths in cancer patients. MicroRNAs (miRNAs), as a subgroup of non-coding RNAs with lengths between 21 and 25 nucleotides, are involved in various cancer processes like chemoresistance via interacting with their target mRNAs and suppressing their expression. Autophagy is a greatly conserved procedure involving the lysosomal degradation of cytoplasmic contents and organelles to deal with environmental stresses like hypoxia and starvation. Autophagy contributes to response to chemotherapy agents: autophagy can act as a protective mechanism for mediating the resistance in response to chemotherapy or can induce autophagic cell death and mediate the sensitivity to chemotherapy. On the other hand, one of the processes targeted by microRNAs in the regulation of chemoresistance is autophagy. Hence, we studied the literatures on chemoresistance mechanisms, the miRNAs' role in cancer, and the miRNAs' role in chemoresistance by modulating autophagy. Graphical Abstract.

Members of the miR-30 family inhibit the epithelial-to-mesenchymal transition of non-small-cell lung cancer cells by suppressing XB130 expression levels

MicroRNAs (miRs) are associated with cancer metastasis. Aberrant expression levels of members of the miR-30 family have been observed in non-small-cell lung cancer (NSCLC). However, the effects of miR-30 family members on the epithelial-to-mesenchymal transition (EMT) of NSCLC cells and the underlying molecular mechanisms have not yet been fully elucidated. The present study investigated the effects of miR-30 family members on EMT, migration and invasion of NSCLC cells and found that overexpression of these miRs inhibited EMT via decreasing the expression levels of N-cadherin, β-catenin and SNAI1, along with weakened migration and invasion abilities. Then, XB130 was identified as a downstream target of the miR-30 family members. XB130-knockdown also inhibited EMT of NSCLC cells, whereas ectopic overexpression of XB130 partly rescued the suppressive effects of miR-30c and miR-30d on EMT. In conclusion, miR-30 family members inhibited EMT of NSCLC cells, partially via suppressing XB130 expression levels.

MiR-30a-5p promotes cholangiocarcinoma cell proliferation through targeting SOCS3

Background: MicroRNAs (miRNAs) play important roles in the occurrence and development of cancers. In this project, we aimed to explore the role and molecular mechanism of mir-30a-5p in cholangiocarcinoma (CCA).

Materials and Methods: The expression profile and clinical significance of miR-30a-5p in CCA patients were investigated in 31 ICC and 52 ECC patients respectively. The role and mechanism of miR-30a-5p in CCA cells were investigated by up-regulating and inhibiting miR-30a-5p expression in vitro functional study.

Results: The expression of miR-30a-5p was increased in both CCA tissues and cells. The inhibition of miR-30a-5p decreased cell proliferation and induced cell apoptosis while overexpression of miR-30a-5p achieved the opposite effect. Furthermore, SOCS3 was down-regulated in ICC and ECC tissues and negatively regulated by miR-30a-5p. Dual-luciferase reporter assay revealed that co-transfection of miR-30a-5p significantly inhibited the activity of firefly luciferase reporter carrying the wild-type 3′UTR of SOCS3. The inhibition of SOCS3 could largely rescue the inhibitory effect of miR-30a-5p inhibition on CCA cells proliferation. In clinical, up-regulated miR-30a-5p expression was correlated with large tumor size in both ICC and ECC cohorts.

Conclusions: miR-30a-5p promoted CCA cells proliferation through targeting SOCS3. These findings suggested that miR-30a-5p could be a potential therapeutic target.

Mir-30b-3p affects the migration and invasion function of ovarian cancer cells by targeting the CTHRC1 gene

BACKGROUND

The aim of this study was to investigate the effect role and mechanism of miR-30b-3p on ovarian cancer cells biological function.

METHODS

The expression of miR-30b-3p was detected in ovarian cancer cell lines and normal ovarian epithelial cell line by qRT-PCR. Mir-30b-3p mimic was transfected into OVCAR3 cells. Cell-counting kit-8 (CCK-8) assay was conducted to explore the effect of mir-30b-3p on the OVCAR3 cells' proliferation. Cell cycle and apoptosis were detected by Flow cytometry. Cell invasion ability was detected by Transwell test. The regulation of putative target of miR-30b-3p was verified by double luciferase reporter assays and Western blot.

RESULT

We found that miR-30b-3p was downregulated in OVCAR3 cells. Overexpression of miR-30b-3p suppressed proliferation, promoted apoptosis, slowed cell cycle and inhibited migration and invasion of OVCAR3 cells. Bioinformatics analysis identified 3'-untranslated region (3'UTR) of Collagen triple helix repeat-containing 1 (CTHRC1) as the presumed binding site for miR-30b-3p. Detection of double luciferase reporter and Western-Blot result confirmed that CTHRC1 was the target gene of miR-30b-3p. Furthermore, E-cadherin, β-cadherin and Vimentin protein expression level were changed after transfection of miR-30b-3p.

CONCLUSION

miR-30b-3p function as an anti-cancer gene. Overexpression of miR-30b-3p can inhibit the biological function of ovarian cancer cells. MiR-30b-3p targets CTHRC1 gene plays an important role in epithelial-mesenchymal transformation (EMT), and supports miR-30b-3p as a potential biological indicator for ovarian cancer in the future.

Intrinsic adriamycin resistance in p53-mutated breast cancer is related to the miR-30c/FANCF/REV1-mediated DNA damage response

Adriamycin(ADR) is still considered to be one of the most effective agents in the treatment of breast cancer (BrCa), its efficacy is compromised by intrinsic resistance or acquire characteristics of multidrug resistance. At present, there are few genetic alterations that can be exploited as biomarkers to guide targeted use of ADR in clinical. Therefore, exploring the determinants of ADR sensitivity is pertinent for their optimal clinical application. TP53 is the most frequently mutated gene in human BrCa, p53 mutation has been reported to be closely related to ADR resistance, whereas the underlying mechanisms that cause endogenous ADR resistance in p53-mutant BrCa cells are not completely understood. The aim of the present study was to investigate the potential roles of miRNA in the response to ADR in p53-mutated breast cancer. Here, we report that BrCa cells expressing mutp53 are more resistant to ADR than cells with wild-type p53 (wtp53). The DNA repair protein- Fanconi anemia complementation group F protein (FANCF) and the translesion synthesis DNA polymerase REV1 protein is frequently abundant in the context of mutant p53 of BrCa. By targeting two key factors, miR-30c increases the sensitivity of BrCa cells to ADR. Furthermore, p53 directly activates the transcription of miR-30c by binding to its promoter. Subsequent analyses revealed that p53 regulates REV1 and FANCF by modulating miR-30c expression. Mutation of the p53 abolished this response. Consistently, reduced miR-30c expression is highly correlated with human BrCa with p53 mutational status and is associated with poor survival. We propose that one of the pathways affected by mutant p53 to increase intrinsic resistance to ADR involves miR-30c downregulation and the consequent upregulation of FANCF and REV1. The novel miRNA-mediated pathway that regulates chemoresistance in breast cancer will facilitate the development of novel therapeutic strategies.

MiR-30a-5p frequently downregulated in prostate cancer inhibits cell proliferation via targeting PCLAF

MicroRNAs (miRNAs) have vastly expanded our view of RNA world in intracellular signal regulating networks. Here, we functionally characterized a normally highly expressed miRNA, miR-30a-5p (MIMAT0000087), which exhibits downregulated expression profiles in prostate cancer samples. MiR-30a-5p knockdown and overexpression in PC-3 cell line alters cell proliferation supporting a tumour suppressor role. We also discovered that PCLAF is the direct target of miR-30a-5p. Notably, PC-3 cell proliferation is inhibited by miR-30a-5p/PCLAF axis. miR-30a-5p represents a novel molecule of functionally important miRNAs which may shed light on the novel therapeutic targets for prostate cancer.

Semaphorin 3A Contributes to Secondary Blood-Brain Barrier Damage After Traumatic Brain Injury

Semaphorin 3A (SEMA3A) is a member of the Semaphorins family, a class of membrane-associated protein that participates in the construction of nerve networks. SEMA3A has been reported to affect vascular permeability previously, but its influence in traumatic brain injury (TBI) is still unknown. To investigate the effects of SEMA3A, we used a mouse TBI model with a controlled cortical impact (CCI) device and a blood–brain barrier (BBB) injury model in vitro with oxygen-glucose deprivation (OGD). We tested post-TBI changes in SEMA3A, and its related receptors (Nrp-1 and plexin-A1) expression and distribution through western blotting and double-immunofluorescence staining, respectively. Neurological outcomes were evaluated by modified neurological severity scores (mNSSs) and beam-walking test. We examined BBB damage through Evans Blue dye extravasation, brain water content, and western blotting for VE-cadherin and p-VE-cadherin in vivo, and we examined the endothelial cell barrier through hopping probe ion conductance microscopy (HPICM), transwell leakage, and western blotting for VE-cadherin and p-VE-cadherin in vitro. Changes in miR-30b-5p were assessed by RT-PCR. Finally, the neuroprotective function of miR-30b-5p is measured by brain water content, mNSSs and beam-walking test. SEMA3A expression varied following TBI and peaked on the third day which expressed approximate fourfold increase compared with sham group, with the protein concentrated at the lesion boundary. SEMA3A contributed to neurological function deficits and secondary BBB damage in vivo. Our results demonstrated that SEMA3A level following OGD injury almost doubled than control group, and the negative effects of OGD injury can be improved by blocking SEMA3A expression. Furthermore, the expression of miR-30b-5p decreased approximate 40% at the third day and 60% at the seventh day post-CCI. OGD injury also exhibited an effect to approximately decrease 50% of miR-30b-5p expression. Additionally, the expression of SEMA3A post-TBI is regulated by miR-30b-5p, and miR-30b-5p could improve neurological outcomes post-TBI efficiently. Our results demonstrate that SEMA3A is a significant factor in secondary BBB damage after TBI and can be abolished by miR-30b-5p, which represents a potential therapeutic target.

Large-scale validation of miRNAs by disease association, evolutionary conservation and pathway activity

The validation of microRNAs (miRNAs) identified by next generation sequencing involves amplification-free and hybridization-based detection of transcripts as criteria for confirming valid miRNAs. Since respective validation is frequently not performed, miRNA repositories likely still contain a substantial fraction of false positive candidates while true miRNAs are not stored in the repositories yet. Especially if downstream analyses are performed with these candidates (e.g. target or pathway prediction), the results may be misleading. In the present study, we evaluated 558 mature miRNAs from miRBase and 1,709 miRNA candidates from next generation sequencing experiments by amplification-free hybridization and investigated their distributions in patients with various disease conditions. Notably, the most significant miRNAs in diseases are often not contained in the miRBase. However, these candidates are evolutionary highly conserved. From the expression patterns, target gene and pathway analyses and evolutionary conservation analyses, we were able to shed light on the complexity of miRNAs in humans. Our data also highlight that a more thorough validation of miRNAs identified by next generation sequencing is required. The results are available in miRCarta ( https://mircarta.cs.uni-saarland.de ).

miR-30 Family Reduction Maintains Self-Renewal and Promotes Tumorigenesis in NSCLC-Initiating Cells by Targeting Oncogene TM4SF1

Increasing evidence indicates that tumor-initiating cells (TICs) are responsible for the occurrence, development, recurrence, and development of the drug resistance of cancer. MicroRNA (miRNA) plays a significant functional role by directly regulating targets of TIC-triggered non-small-cell lung cancer (NSCLC), but little is known about the function of the miR-30 family in TICs. In this study, we found the miR-30 family to be downregulated during the spheroid formation of NSCLC cells, and patients with lower miR-30a/c expression had shorter overall survival (OS) and progression-free survival (PFS). Moreover, transmembrane 4 super family member 1 (TM4SF1) was confirmed to be a direct target of miR-30a/c. Concomitant low expression of miR-30a/c and high expression of TM4SF1 correlated with a shorter median OS and PFS in NSCLC patients. miR-30a/c significantly inhibited stem-like characteristics in vitro and in vivo via suppression of its target gene TM4SF1, and then it inhibited the activity of the mTOR/AKT-signaling pathway. Thus, our data provide the first evidence that TM4SF1 is a direct target of miR-30a/c and miR-30a/c inhibits the stemness and proliferation of NSCLC cells by targeting TM4SF1, suggesting that miR-30a/c and TM4SF1 may be useful as tumor biomarkers for the diagnosis and treatment of NSCLC patients.

MiR-876-5p suppresses epithelial-mesenchymal transition of lung cancer by directly down-regulating bone morphogenetic protein 4

Lung cancer is the leading cause of cancer-related death throughout the world. We aimed to investigate the role of a novel microRNA-876-5p and its potential molecular target bone morphogenetic protein 4 (BMP-4), in the epithelial-mesenchymal transition (EMT) of lung cancer. Expressions of microRNA-876-5p and its potential target BMP-4 were analysed in lung cancer cells and patient tissues. Luciferase activity assay was conducted to verify direct targeting of microRNA- 876-5p to the 3'-UTR of BMP-4 mRNA. Migration, invasion capacities of lung cancer cells expressing microRNA-876-5p were analysed, and characteristics of lung cancer EMT protein markers were also evaluated. A xenograft tumour mouse model was established to address the roles of microRNA-876-5p and BMP-4 in lung cancer EMT in vivo. MicroRNA-876- 5p was decreased while BMP-4 was increased in lung cancer cells and tissues. MicroRNA-876-5p directly targeted 3'-UTR of BMP-4 mRNA to inhibit its expression. MicroRNA-876-5p expression significantly inhibited the migration, invasion and EMT of lung cancer cells in vitro, as well as metastasis in vivo, which required BMP-4 expression. MicroRNA-876-5p suppresses EMT of lung cancer by directly down-regulating BMP-4, both of which could serve as potential therapeutic targets in the treatment of lung cancer.

Expression of miR-30c and BCL-9 in gastric carcinoma tissues and their function in the development of gastric cancer

microRNA-30c (miR-30c) is a member of the miR-30s family, which is known to serve important roles in the occurrence and development of numerous tumor types. Our previous microarray analysis of extracted RNA from tissue samples was conducted to examine the expression of miR-30c and predict miR-30c target genes. In the present study, it was determined that the expression of miR-30c was differentially expressed in 82 paired gastric cancer (GC) and paracancerous tissues. Cellular expression of miR-30c in two GC cell lines MKN-45, MKN-74 and one non-cancer cell line GES-1 was modified using the miR-30c-mimic and miR-30c-inhibitor reagents, in a series of transfection experiments. Following transfection of cancer and non-cancer cell lines with the miR-30c-mimic, cell proliferation and apoptosis rates were increased. Compared with the NC group, MKN-74 cell proliferation was significantly inhibited (P<0.05) following transfection with the miR-30c-mimic at 48 and 24 h, GES-1 was significantly inhibited (P<0.05) at 24 and 48 h, and apoptosis was significantly reduced in transfected MKN-74 cells (P<0.05). The clinicopathological data and the expression of BCL-9 and miR-30c in patients with GC were used to identify associations. The expression levels of miR-30c were associated with age. Western blot analysis demonstrated that the BCL-9 expression levels in MKN-74 cells were higher following transfection with the miR-30c-mimic, and were lower following transfection with the miR-30c-inhibitor, both compared with the negative control group. It was concluded that compared with the negative control group, the expression of miR-30c was low in GC tissues and may be involved in GC development via regulation of proliferation, apoptosis and the cell cycle.

Functional miRNA variants affect lung cancer susceptibility and platinum-based chemotherapy response

Background

Platinum-based chemotherapy is widely used as the first-line treatment of lung cancer. MicroRNAs have an important role in lung carcinogenesis and progression. Single-nucleotide polymorphisms (SNPs) in miRNA involved in miRNA biogenesis and structural alteration may affect miRNA expression. In this study, we aimed to investigate the association of functional miRNA variants with the lung cancer susceptibility and platinum-based chemotherapy response.

Methods

Nine genetic polymorphisms in miR-605, 146a, 149, 196a-2, 27a, 499, 30c-1, 5197 and let-7a-2 were selected with comprehensive collection strategy and genotyped by MALDI-TOF mass spectrometry in a total of 215 health control and 507 lung cancer patients (386 patients received at least two consecutive cycles of platinum-based chemotherapy).

Results

We found that an allele carriers of miR-146a rs2910164 (P=0.022, OR=1.315) and C allele carriers of miR-149 rs71428439 (P=0.042, OR=1.372) performance a high risk of lung cancer. Mir-30c-1 rs928508 (P=0.005, in recessive model) and let-7a-2 rs629367 (P=0.030 and P=0.021, in additive and dominant models, respectively) showed strong relationship with lung cancer risk in age under 57 years. The rs11614913 (miR-196a-2) C allele or rs9280508 (miR-30c-1) G allele carriers shown more sensitive to platinum both in additive (P=0.010, P=0.022, respectively) and dominant models (P=0.001, P=0.018, respectively).

Conclusions

These findings suggested that SNPs rs71428439 (miR-149), rs2910164 (miR-146a), rs928508 (mir-30c-1) and rs629367 (let-7a-2) were associated with the lung cancer prevalence, polymorphisms of rs11614913 (miR-196a-2) and rs9280508 (miR-30c-1) significantly influenced the patients' response to platinum-based chemotherapy, which may serve as potential clinical biomarkers to predict lung cancer risk and platinum-based chemotherapy response.

miR-30 Family: A Promising Regulator in Development and Disease

MicroRNAs (miRNAs) are small noncoding RNAs that negatively regulate posttranscriptional expression of target genes. Accumulating evidences have demonstrated that the miR-30 family, as a member of microRNAs, played a crucial regulating role in the development of tissues and organs and the pathogenesis of clinical diseases, which indicated that it may be a promising regulator in development and disease. This review aims to clarify the current progress on the regulating role of miR-30 family in tissues and organs development and related disease and highlight their research prospective in the future.

MicroRNA-30b targets Snail to impede epithelial-mesenchymal transition in pancreatic cancer stem cells

Snail-mediated epithelial-mesenchymal transition (EMT) process plays a fundamental role in facilitating pancreatic ductal adenocarcinoma (PDAC) stemness and metastasis. In the present study, we revealed that microRNA-30 (miR-30) members, especially miR-30b, were remarkably downregulated in triple-positive (CD24⁺, CD44⁺, EpCAM⁺) pancreatic cancer stem cells (PCSCs). In addition, we revealed that miR-30b suppressed EMT process in PCSCs. Overexpression of miR-30b led to reduced expression of mesenchymal marker N-cadherin and the upregulation of epithelial marker E-cadherin. Moreover, both of TargetScan and PicTar algorithms predicted that miR-30b directly targeted Snail 3'UTR. Luciferase reporter assay showed that miR-30b could specifically reduce the translational activity of Snail wild-type 3'UTR, but not its mutant form. In line with these results, transwell assay demonstrated that overexpression of miR-30b mimic impaired migratory and invasive capacities of PCSCs. Furthermore, miR-30b overexpression suppresses in vivo tumorigenic potential of PDACs. Finally, a negative correlation between the expression of miR-30b and Snail was uncovered. Low level of miR-30b and high Snail expression both predict dismal prognosis in PDAC patients. Taken together, these findings implicate that miR-30b may suppress PCSC phenotype and PDAC metastasis through posttranscriptionally suppressing Snail expression, highlighting that miR-30b may serve as a therapeutic agent in the treatment of PDAC.

Absent expression of miR-30a promotes the growth of lung cancer cells by targeting MEF2D

The microRNA (miR)-30 family has been reported to be aberrantly expressed in several types of cancer. However, its contributions to lung cancer remain to be fully elucidated. Myocyte enhancer factor 2D (MEF2D), an oncogene in liver cancer, has been shown to be aberrantly expressed in lung cancer. In the present study, it was found that MEF2D and miR-30a were inversely correlated in lung cancer samples. Using an online database, it was predicted that miR-30a targeted the 3' untranslated region (UTR) of MEF2D mRNA. The activity of luciferase with MEF2D 3'UTR was suppressed by transfecting cells with miR-30a mimics. The results of western blot analysis showed that the miR-30a mimics also suppressed the MEF2D protein. The miR-30a mimics were able to reduce the growth and colonies of lung cancer cells by suppressing MEF2D. The results of FACS and western blot assays showed that the apoptotic rate was reduced by transfection with the miR-30a mimics. Collectively, the aberrant expression of miR-30a in lung cancer promoted the expression of MEF2D protein. miR-30a inhibited the growth and colony formation of the lung cancer cells by promoting apoptosis.

Extracellular vesicle-encapsulated miR-30e suppresses cholangiocarcinoma cell invasion and migration via inhibiting epithelial-mesenchymal transition

Early-staged cholangiocarcinoma (CCA) is difficult to diagnose due to its high potential for invasion and metastasis. Epithelial-mesenchymal transition (EMT) is induced by transforming growth factor-β (TGF-β) in a process thought to be important for invasion and metastasis in several cancers, including CCA. Although microRNAs (miRNAs) have been implicated in the pathogenesis of several malignancies, their roles to CCA are not clearly understood. Some miRNAs were reported to be included in extracellular vesicles (EVs) and transferred from their donor cells to other cells, modulating recipient cell behaviors. In this study, the involvement and functional roles of EV-contained miRNAs during EMT in human CCA were determined. Expression profiling identified a subset of miRNAs that were reduced by TGF-β in CCA cells. Among these, miR-30e was highly downregulated by TGF-β and predicted to target Snail, which is an EMT-inducible transcription factor. MiR-30e overexpression suppressed cell invasion and migration via inhibiting EMT, whereas miR-30e inhibition promoted EMT, cell invasion and migration. Moreover, miR-30e was enriched in EVs derived from CCA cells after miR-30e overexpression, and miR-30e intercellular transfer through EVs suppressed EMT, cell invasion and migration in recipient CCA cells. Together, our results suggest that EV-mediated miR-30e transfer could inhibit EMT via directly targeting Snail, which subsequently suppresses CCA cell invasion and migration. These findings provide several new insights into regulatory mechanisms of tumor invasion and metastasis in human CCA.

Non-coding RNAs as emerging regulators of epithelial to mesenchymal transition in non-small cell lung cancer

Non-small cell lung cancer (NSCLC) remains a major health problem that patients suffer from around the world. The epithelial to mesenchymal transition (EMT) has attractive roles in increasing malignant potential and reducing sensitivity to conventional therapeutics in NSCLC cells. Meanwhile, it is now evident that non-coding RNAs (ncRNAs), primarily microRNAs and long non-coding RNAs contribute to tumorigenesis partially via regulating EMT. This article briefly summarizes current researches about EMT-related ncRNAs in NSCLC and discusses their crucial roles in the complex regulatory network. Also, the authors will show the evidence that ncRNAs not only contribute to cancer cells migration and invasion, but also take charge of the resistance of chemotherapy, radiotherapy and EGFR-TIKs. Then, we will further discuss the potential of inhibition of EMT via manipulating relevant ncRNAs to change our current treatment of NSCLC patients.

miR-30c Impedes Glioblastoma Cell Proliferation and Migration by Targeting SOX9

miR-30c has been acknowledged as a tumor suppressor in various human cancers, such as ovarian cancer, gastric cancer, and prostate cancer. However, the role of miR-30c in glioblastoma (GBM) needs to be investigated. In our study, we found that the expression of miR-30c was significantly downregulated in GBM tissues and cell lines. We found that overexpression of miR-30c inhibited cellular proliferation of GBM cells in vitro and in vivo. More GBM cells were arrested in the G₀ phase after miR-30c overexpression. Moreover, we showed that miR-30c overexpression suppressed the migration and invasion of GBM cells. Mechanistically, we found that SOX9 was a direct target of miR-30c in GBM cells. Overexpression of miR-30c inhibited the mRNA and protein levels of SOX9 in GBM cells. Moreover, there was a negative correlation between the expression of miR-30c and SOX9 in GBM tissues. Finally, we showed that restoration of SOX9 in GBM cells reversed the proliferation, migration, and invasion of GBM cells transfected with miR-30c mimic. Collectively, our results demonstrated that miR-30c suppressed the proliferation, migration, and invasion of GBM cells via targeting SOX9.

MicroRNA-30c functions as a tumor suppressor via targeting SNAI1 in esophageal squamous cell carcinoma

BACKGROUND

Aberrant expression of miRNAs was involved in tumor initiation, progression and metastasis in multiple cancers. Many kinds of microRNAs in esophageal squamous cell carcinoma (ESCC) have been researched, whereas miR-30c has not been included.

METHODS

Firstly, we explored the expression of miR-30c in ESCC tissue and serum samples and its relations to the survival. To further investigate its effects on ESCC cells, we completed a series of experiments. We detected the effects of ectopic miR-30c expression on the proliferation, migration and invasion of ESCC cells in vitro. We identified the target role of SNAI1 in ESCC using Dual-luciferase reporter assay and western blot assay.

RESULTS

The results showed miR-30c was significant down-regulated in ESCC tissues and cell lines. Clinically, we found lower miR-30c expression was significantly correlated with worse ESCC progression and survival. Also we clarified that miR-30c suppressed cell proliferation, invasion and epithelial to mesenchymal transition (EMT) of ESCC cell lines. What's more, we figured out that miR-30c inhibits ESCC biological behaviors and EMT progress by directly binding to the 3'-UTR of SNAI1.

CONCLUSION

This study provides new insight into the mechanism responsible for the development of human ESCC. Therefore, miR-30c could be a promising biomarker and a therapeutic target for ESCC in the future.

MiR-30c-5p suppresses migration, invasion and epithelial to mesenchymal transition of gastric cancer via targeting MTA1

BACKGROUND

In China, gastric cancer (GC) is an ordinary malignant tumor. Recent literatures have shown that microRNA is critical during tumorigenesis. This study focuses on the influence of miR-30c-5p on the metastasis of GC and further explores its underlying mechanism.

METHODS

Before the study, expression level of miR-30c-5p and targeted protein was detected in 40 GC tissue samples and 5 GC cells by RT-qPCR. Meanwhile, correlation analysis was conducted between miR-30c-5p expression level and clinicopathological features. In addition, wound healing assay and cell invasion assay were utilized to identify whether miR-30c-5p could affect the migrated and invaded ability of GC cells. Western blotting assay and luciferase assay were used to explore the potential mechanism.

RESULTS

In GC tissues, miR-30c-5p expression level was significantly lower and was remarkably related with clinical features such as tumor node metastasis(TNM) stage and lymphatic metastasis. Moreover, the migrated and invaded ability of GC cells was enhanced through knockdown of miR-30c-5p, while overexpression of miR-30c-5p presented with reversed effect. Further study showed that miR-30c-5p inhibited the expression of its target spot, metastasis-associated protein 1(MTA1), and then suppressed the process of epithelial to mesenchymal transition(EMT) which was important in the metastasis of GC.

CONCLUSION

The results indicate that miR-30c-5p, a novel suppressor in tumorigenesis, could inhibit the metastasis and EMT via MTA1, which may offer a possible therapeutic target in GC.

Epithelial-to-Mesenchymal Transition and MicroRNAs in Lung Cancer

Despite major advances, non-small cell lung cancer (NSCLC) remains the major cause of cancer-related death in developed countries. Metastasis and drug resistance are the main factors contributing to relapse and death. Epithelial-to-mesenchymal transition (EMT) is a complex molecular and cellular process involved in tissue remodelling that was extensively studied as an actor of tumour progression, metastasis and drug resistance in many cancer types and in lung cancers. Here we described with an emphasis on NSCLC how the changes in signalling pathways, transcription factors expression or microRNAs that occur in cancer promote EMT. Understanding the biology of EMT will help to define reversing process and treatment strategies. We will see that this complex mechanism is related to inflammation, cell mobility and stem cell features and that it is a dynamic process. The existence of intermediate phenotypes and tumour heterogeneity may be debated in the literature concerning EMT markers, EMT signatures and clinical consequences in NSCLC. However, given the role of EMT in metastasis and in drug resistance the development of EMT inhibitors is an interesting approach to counteract tumour progression and drug resistance. This review describes EMT involvement in cancer with an emphasis on NSCLC and microRNA regulation.

STIM1 silencing inhibits the migration and invasion of A549 cells

The present study aimed to explore the effects of stromal interaction molecule 1 (STIM1) knockdown on the migration, invasion and metastasis of A549 cells in vitro and in vivo. Western blotting and immunohistochemistry were used to detect protein expression levels. Wound healing and Transwell invasion assays were used to assess the migratory and invasive abilities of A549 cells transfected with STIM1-specific short hairpin (sh)RNA (shSTIM1). In addition, a tail vein metastatic assay was performed. The results demonstrated that the frequency of STIM1 high-expression was significantly increased in metastatic lung cancer tissues (72.2%) compared with in non-metastatic lung cancer tissues (33.0%). STIM1 knockdown inhibited A549 cell migration and invasion in vitro and tumor metastasis in vivo. The protein expression levels of Snail1, Vimentin, matrix metalloproteinase (MMP) 2 and MMP9 were markedly decreased in A549-shSTIM1 compared with in A549 cells transfected with control shRNA (shcon). In addition, the protein expression levels of E-cadherin were markedly increased in A549-shSTIM1 cells compared with in A549-shcon cells. These results suggested that STIM1 knockdown may inhibit the migration and invasion of A549 cells in vitro, and metastasis in vivo.

Low expression of microRNA-30c promotes prostate cancer cells invasion involved in downregulation of KRAS protein

Aberrant microRNA expression is associated with tumor development. The present study aimed to elucidate the role of miR-30c in the development of prostate cancer. Quantitative polymerase chain reaction was performed to compare miR-30c expression in LNCaP, DU145, PC-3 and RWPE-1 cell lines. Lentivirus expressing miR-30c was used to create stable overexpression cell lines to investigate the effects of miR-30c overexpression on cell proliferation, migration and invasion, which were determined in the prostate cancer cell line PC-3 by MTT, colony formation, wound healing and Transwell assays. Effects of miR-30c on KRAS were examined by western blot analysis. miR-30c expression was significantly lower (P<0.05) in the PC-3 cell line compared with LNCaP, DU145 and RWPE-1 cell lines. miR-30c overexpression in PC-3 inhibited tumor cell proliferation, migration and invasion in vitro. Furthermore, KRAS protein expression was downregulated in miR-30c overexpression cell lines compared with the negative control (NC) group (P<0.05). The present results demonstrated that overexpression of miR-30c inhibits prostate cancer cell line proliferation, migration and invasion, which was possibly caused by downregulation of KRAS protein by miR-30c. The data implicate miR-30c in the prognosis and treatment of prostate cancer.

MiR-30c protects diabetic nephropathy by suppressing epithelial-to-mesenchymal transition in db/db mice

Epithelial‐to‐mesenchymal transition (EMT) plays a significant role in tubulointerstitial fibrosis, which is a hallmark of diabetic nephropathy. Thus, identifying the mechanisms of EMT activation could be meaningful. In this study, loss of miR‐30c accompanied with increased EMT was observed in renal tubules of db/db mice and cultured HK2 cells exposed to high glucose. To further explore the roles of miR‐30c in EMT and tubulointerstitial fibrosis, recombinant adeno‐associated viral vector was applied to manipulate the expression of miR‐30c. In vivo study showed that overexpression of miR‐30c suppressed EMT, attenuated renal tubulointerstitial fibrosis and reduced proteinuria, serum creatinine, and BUN levels. In addition, Snail1 was identified as a direct target of miR‐30c by Ago2 co‐immunoprecipitation, luciferase reporter, and Western blot assays. Downregulating Snail1 by siRNA reduced high glucose‐induced EMT in HK2 cells, and miR‐30c mimicked the effects. Moreover, miR‐30c inhibited Snail1‐TGF‐β1 axis in tubular epithelial cells undergoing EMT and thereby impeded the release of TGF‐β1; oppositely, knockdown of miR‐30c enhanced the secretion of TGF‐β1 from epitheliums and significantly promoted proliferation of fibroblasts and fibrogenesis of myofibroblasts, aggravated tubulointerstitial fibrosis, and dysfunction of diabetic nephropathy. These results suggest a protective role of miR‐30c against diabetic nephropathy by suppressing EMT via inhibiting Snail1‐TGF‐β1 pathway.

The miR-30 family: Versatile players in breast cancer

The microRNA family, miR-30, plays diverse roles in regulating key aspects of neoplastic transformation, metastasis, and clinical outcomes in different types of tumors. Accumulating evidence proves that miR-30 family is pivotal in the breast cancer development by controlling critical signaling pathways and relevant oncogenes. Here, we review the roles of miR-30 family members in the tumorigenesis, metastasis, and drug resistance of breast cancer, and their application to predict the prognosis of breast cancer patients. We think miR-30 family members would be promising biomarkers for breast cancer and may bring a novel insight in molecular targeted therapy of breast cancer.

MicroRNA-29a functions as a potential tumor suppressor through directly targeting CDC42 in non-small cell lung cancer

The expression and function of microRNA-29a (miR-29a) have been investigated in various types of cancer. In the present study, the expression, function and underlying molecular mechanism of miR-29a were investigated in non-small cell lung cancer (NSCLC). The expression level of miR-29a in NSCLC was determined using reverse transcription-quantitative polymerase chain reaction (RT-qPCR). Cell proliferation, migration and invasion ability were determined using Cell Counting Kit-8, cell migration and invasion assays, respectively. Bioinformatics analysis and dual-luciferase reporter assays were performed to determine whether cell division cycle 42 (CDC42) is a direct target gene of miR-29a. To assess CDC42 mRNA and protein expression following transfection with miR-29a, RT-qPCR and western blotting were performed. Following knockdown of CDC42, functional assays were performed to investigate the roles of CDC42 in NSCLC. The results demonstrated that miR-29a was downregulated in NSCLC and the decreased expression level of miR-29a was significantly associated with advanced tumor-node-metastasis classification and metastasis. In addition, upregulation of miR-29a inhibited cell proliferation, migration and invasion in NSCLC, whereas downregulation of miR-29a had the opposite effects. Furthermore, CDC42 was identified as a direct target gene of miR-29a in vitro. miR-29a was demonstrated to function as a tumor suppressor in NSCLC by directly targeting CDC42 and may be investigated further as a target therapy for NSCLC.

MiR-30c-2* negative regulated MTA-1 expression involved in metastasis and drug resistance of HPV-infected non-small cell lung cancer

BACKGROUND

MiR-30c-2* is considered to be a tumor suppressor microRNA in various cancers and is associated with gemcitabine sensitivity of lung cancer cells. Downregulation of miR-30c-2* promotes tumor invasion via increased expression of metastasis-associated protein-1. We hypothesized that downregulated expression of miR-30c-2* was involved in human papillomavirus-associated lung tumorigenesis and drug resistance.

METHODS

We examined whether expression of human papillomavirus 16/18 oncoprotein and miR-30c-2*-associated genes could be linked to patient outcome by collecting 319 lung tumors from patients with non-small cell lung cancer to determine expression of human papillomavirus 16/18 E6 protein, miR-30c-2*, and miR-30c-2* downstream metastasis-associated protein-1 mRNA by immunohistochemical and real-time polymerase chain reaction analysis.

RESULTS

Our results showed that miR-30C-2* levels were increased 45-fold in the E6-knockdown TL-1 cells when compared with levels in the parental cells. More interestingly, metastasis-associated protein-1 expression correlated negatively with miR-30C-2* and positively with human papillomavirus 16 E6 protein expression in lung tumors from lung cancer patients. Metastasis-associated protein-1 expression levels in the tumor tissues correlated positively with tumor stage and nodal metastasis. Patients with high metastasis-associated protein-1 expression, and especially patients infected with human papillomavirus, experienced a poor clinical outcome, tumor recurrence, and a poor therapeutic response compared with those with low metastasis-associated protein-1 expression.

CONCLUSION

These results showed that miR-30C-2* and levels of downstream metastasis-associated protein-1 gene expression in the tumor tissues of patients could be useful in predicting clinical outcome and therapeutic response and in selecting useful therapeutic drugs for lung cancer patients, especially patients with human papillomavirus infection.

Extracellular vesicles as a source for non-invasive biomarkers in bladder cancer progression

Bladder cancer is the second most frequent malignancy of the urinary tract after prostate cancer. Current diagnostic techniques, such as cystoscopy and biopsies are highly invasive and accompanied of undesirable side effects. Moreover, there are no suitable biomarkers for relapse or progression prognosis. We analysed whether the specific composition of microRNAs (miRNAs) and proteins of extracellular vesicles (EVs) that urothelial tumour cells of bladder mucosa release into the urine, could reflect their pathologic condition. For this purpose, urinary EVs were isolated and their protein and miRNA composition evaluated in healthy donors and low or high-grade bladder cancer patients. Using a microarray platform containing probes for 851 human miRNAs we found 26 deregulated miRNAs in high-grade bladder cancer urine EVs, from which 23 were downregulated and 3 upregulated. Real-time PCR analysis pointed to miR-375 as a biomarker for high-grade bladder cancer while miR-146a could identify low-grade patients. Finally, several protein markers were also deregulated in EVs from tumour patients. Our data suggest that the presence of ApoB in the 100,000 pellet is a clear marker for malignancy.

[Advanced Research on MicroRNAs and EGFR-TKIs Secondary Resistance]

肺癌是癌症致死率最高的疾病，关于这个疾病的发生机制已得到部分阐明，其中表皮生长因子受体（epidermal growth factor receptor, EGFR）信号通路研究最为深入，在肺癌的发生中起着至关重要的作用。而有效地抑制EGFR信号通路的药物已用于非小细胞肺癌（non-small cell lung cancer, NSCLC）的靶向治疗中，伴有EGFR基因突变的患者使用EGFR酪氨酸激酶抑制剂（EGFR-tyrosine kinase inhibitors, EGFR-TKIs）治疗后获得不错的临床收益，但大部分患者在使用该药治疗10个月后出现耐药现象。MiRNAs（microRNAs）是一种非编码蛋白的RNA，参与转录后水平基因的表达调控。越来越多的研究发现miRNAs与EGFR-TKIs继发性耐药有关，miRNAs可作为逆转EGFR-TKIs耐药及评估EGFR-TKIs有效性的生物指标。本文就NSCLC中miRNAs与EGFR-TKIs继发性耐药机制之间的相关性研究进展做简要的综述。

Prognostic Values of Vimentin Expression and Its Clinicopathological Significance in Non-Small Cell Lung Cancer: A Meta-Analysis of Observational Studies with 4118 Cases

BACKGROUND

Vimentin is a member of the intermediate filament proteins and a canonical marker of the epithelial-mesenchymal transition (EMT), which is pivotal in tumorigenesis, metastasis and invasion in non-small cell lung cancer (NSCLC). The current meta-analysis aimed to investigate the associations between vimentin and prognosis and progression in NSCLC.

METHODS

Databases with literature published in English, including PubMed, Web of Science, Embase, Science Direct, Wiley Online Library, Ovid, Cochrane Central Register of Controlled Trials, LILACS and Google Scholar, and the CNKI, VIP, CBM and WanFang databases in Chinese were used for the literature search. The key terms included (1) 'vimentin' OR 'vim' OR 'vmt' OR 'vm' OR 'hel113' OR 'ctrct30' and (2) 'pulmon*' OR 'lung' OR 'alveolar' and (3) 'cancer' OR 'carcinoma' OR 'tumor' OR 'adenocarcinoma' OR 'squamous' OR 'neoplas*' OR 'malignan*'. The data were combined by random effect model and the H value and I2 were used to assess the heterogeneity. All the meta-analysis was conducted using Stata 12.0.

RESULTS

Thirty-two qualified studies (4118 cases) were included in the current meta-analysis. Twelve studies with 1750 patients were included to assess the significance of vimentin in the overall survival (OS) of NSCLC; the pooled hazard ratio (HR) was 1.831 (confidence interval (CI): 1.315-2.550, P<0.001) in the univariate analysis and 1.266 (CI: 0.906-1.768, P = 0.167) in the multivariate analysis. Four studies with 988 cases were applicable to determine the significance of vimentin in the disease-free survival (DFS) of NSCLC; the pooled HR of the DFS was 1.224 (CI: 0.921-1.628, P = 0.164) in the univariate analysis and 1.254 (CI: 0.985-1.956, P = 0.067) in the multivariate analysis. Regarding the relationships between vimentin and clinicopathological factors, the pooled odds ratio (OR) with 3406 NSCLCs indicated that up-regulated vimentin was associated with smoking (OR = 1.359, CI: 1.098-1.683, P = 0.004), poor differentiation (OR = 2.133, CI: 1.664-2.735, P<0.001), an advanced TNM stage (OR = 3.275, CI: 1.987-5.397, P<0.001), vascular invasion (OR = 3.492, CI: 1.063-11.472, P = 0.039), lymph node metastasis (OR = 2.628, CI: 1.857-3.718, P<0.001), recurrence (OR = 1.631, CI: 1.052-2.528, P = 0.029) and pleural invasion (OR = 2.346, CI: 1.397-3.941, P = 0.001). There was no significant correlation between vimentin and age, gender, diameter, T stage, distant metastasis, or marginal invasion (P>0.05).

CONCLUSION

An overexpression of vimentin may predict the progression and an unfavorable survival of NSCLC. Vimentin may represent a helpful biomarker and a potential target for the treatment strategies of NSCLC. Additional, prospective studies with large samples are necessary to confirm the significance of vimentin in NSCLC.

Expression of microRNA-133 inhibits epithelial-mesenchymal transition in lung cancer cells by directly targeting FOXQ1

INTRODUCTION

MicroRNA (miR) was implicated in the tumorigenesis of many types of cancer, but no study was conducted on the exact role of miR-133 in lung cancer.

METHODS

We have identified miR-133 as a putative regulator of FOXQ1 expression, and investigated the potential involvement of miR-133 in the migration and invasion of lung cancer cells, as well as the underlying molecular mechanism.

RESULTS

MiR-133 directly targeted and down-regulated FOXQ1 expression, which in turn reduced TGF-β level. MiR-133 was down-regulated in lung cancer cell lines A549 and HCC827, and its re-expression significantly inhibited the migration and invasion of the lung cancer cells. Further investigation revealed that this inhibition was caused by reversing the epithelial-mesenchymal transition, evidenced by miR-133 induced elevation of epithelial marker E-cadherin, and reduction of mesenchymal marker Vimentin.

CONCLUSIONS

Our study is the first to identify miR-133 as a biomarker for lung cancer. It functions to down-regulate FOXQ1, and inhibit epithelial-mesenchymal transition, which antagonizes lung cancer tumorigenesis. Therefore our data support the role of miR-133 as a potential molecular therapeutic tool in treating lung cancer.

BCL9, a coactivator for Wnt/β-catenin transcription, is targeted by miR-30c and is associated with prostate cancer progression

B-cell lymphoma 9 (BCL9), a component of aberrantly activated Wnt signaling, is an important contributing factor to tumor progression. Our previous data indicated that downregulation of the tumor suppressor microRNA-30c (miR-30c) was a frequent pathogenetic event in prostate cancer (PCa). However, a functional link between miR-30c and BCL9/Wnt signaling, and their clinical and pathological significance in PCa, have not been well established. The present study demonstrated that miR-30c serves as a key negative regulator targeting BCL9 transcription in PCa cells. Ectopic expression of miR-30c was associated with reduced expression of Wnt pathway downstream targets, including c-Myc, cluster of differentiation 44 and sex determining region Y-box 9 in DU145 human PCa cells. Examination of clinical prostate specimens revealed higher levels of BCL9 expression in PCa compared with that in benign prostate tissues. After substantiating this finding by patient sample analysis, BCL9 expression or activity was observed to be closely correlated with PCa biochemical recurrence (BCR) and disease progression, whereas it was inversely associated with miR-30c. Furthermore, overexpression of BCL9 in PCa acted cooperatively with miR-30c low expression to predict earlier BCR in PCa. These findings indicate that inhibition of BCL9/Wnt signaling by miR-30c is important in the progression of PCa. Furthermore, the combined analysis of miR-30c and BCL9 may be valuable tool for prediction of BCR in PCa patients following radical prostatectomy.

Differential expression of circulating microRNAs according to severity of colorectal neoplasia

There is a need to develop a colorectal cancer (CRC) screening test that is noninvasive, cost effective, and sensitive enough to detect preneoplastic lesions. This case-control study examined the feasibility of using circulating extracellular microRNAs (miRNAs) to differentiate a spectrum of colorectal neoplasia of various severity and hence for early detection of colorectal neoplasia. Archived serum samples of 10 normal controls and 31 cases, including 10 with nonadvanced adenoma, 10 with advanced adenoma, and 11 with CRC, were profiled for circulating miRNAs using next-generation sequencing. Multiple linear regression, adjusting for age, gender, and smoking status, compared controls and the 3 case groups for levels of 175 miRNAs that met stringent criteria for miRNA sequencing analysis. Of the 175 miRNAs, 106 miRNAs were downregulated according to severity of neoplasia and showed a relative decrease in the expression from controls to nonadvanced adenoma to advanced adenoma to CRC (Ptrend < 0.05). Pairwise group comparisons showed that 39 and 80 miRNAs were differentially expressed in the advanced adenoma and CRC groups compared with the controls, respectively. Differences in miRNA levels between the nonadvanced adenoma group and controls were modest. Our study found that expression of many miRNAs in serum was inversely correlated with the severity of colorectal neoplasia, and differential miRNA profiles were apparent in preneoplastic cases with advanced lesions, suggesting circulating miRNAs could serve as potential biomarkers for CRC screening.

Enhanced protein production by microRNA-30 family in CHO cells is mediated by the modulation of the ubiquitin pathway

Functional genomics represent a valuable approach to improve culture performance of Chinese hamster ovary (CHO) cell lines for biopharmaceutical manufacturing. Recent advances in applied microRNA (miRNAs) research suggest that these small non-coding RNAs are critical for the regulation of cell phenotypes in CHO cells. However, the notion that individual miRNAs usually control the expression of hundreds of different genes makes miRNA target identification highly complex. We have recently reported that the entire miR-30 family enhances recombinant protein production in CHO cells. To better understand the pro-productive effects of this miRNA family, we set out to identify their downstream target genes in CHO cells. Computational target prediction combined with a comprehensive functional validation enabled the discovery of a set of twenty putative target genes for all productivity enhancing miR-30 family members. We demonstrate that all miR-30 isoforms contribute to the regulation of the ubiquitin pathway in CHO cells by directly targeting the ubiquitin E3 ligase S-phase kinase-associated protein 2 (Skp2). Finally, we provide several lines of evidence that miR-30-mediated modulation of the ubiquitin pathway may enhance recombinant protein expression in CHO cells. In summary, this study supports the importance of non-coding RNAs, especially of miRNAs, in the context of cell line engineering.

Downregulation of miRNA-30c and miR-203a is associated with hepatitis C virus core protein-induced epithelial-mesenchymal transition in normal hepatocytes and hepatocellular carcinoma cells

Hepatitis C virus (HCV) Core protein has been demonstrated to induce epithelial-mesenchymal transition (EMT) and is associated with cancer progression of hepatocellular carcinoma (HCC). However, how the Core protein regulates EMT is still unclear. In this study, HCV Core protein was overexpressed by an adenovirus. The protein levels of EMT markers were measured by Western blot. The xenograft animal model was established by inoculation of HepG2 cells. Results showed that ectopic expression of HCV core protein induced EMT in L02 hepatocytes and HepG2 tumor cells by upregulating vimentin, Sanl1, and Snal2 expression and downregulating E-cadherin expression. Moreover, Core protein downregulated miR-30c and miR-203a levels in L02 and HepG2 cells, but artificial expression of miR-30c and miR-203a reversed Core protein-induced EMT. Further analysis showed that ectopic expression of HCV core protein stimulated cell proliferation, inhibited apoptosis, and increased cell migration, whereas artificial expression of miR-30c and miR-203a significantly reversed the role of Core protein in these cell functions in L02 and HepG2 cells. In the HepG2 xenograft tumor models, artificial expression of miR-30c and miR-203a inhibited EMT and tumor growth. Moreover, L02 cells overexpressing Core protein can form tumors in nude mice. In HCC patients, HCV infection significantly shortened patients' survival time, and loss of miR-30c and miR-203 expression correlated with poor survival. In conclusion, HCV core protein downregulates miR-30c and miR-203a expression, which results in activation of EMT in normal hepatocytes and HCC tumor cells. The Core protein-activated-EMT is involved in the carcinogenesis and progression of HCC. Loss of miR-30c and miR-203a expression is a marker for the poor prognosis of HCC.

miR-15b regulates cisplatin resistance and metastasis by targeting PEBP4 in human lung adenocarcinoma cells

MicroRNAs (miRNAs) have been identified as important posttranscriptional regulators involved in various biological and pathological processes of cells, but their association with tumor chemoresistance has not been fully understood. We detected miR-15b expression in two lung adenocarcinoma cell lines, A549 and A549/CDDP, and then investigated the effects of miR-15b on the metastasis and the chemosensitivity of cancer cells, using both gain- and loss-of-function studies. The correlation between miR-15b level and chemoresistance was further investigated in clinical lung adenocarcinoma specimens. miR-15b was significantly upregulated in cisplatin-resistant lung adenocarcinoma A549/CDDP cells compared with parental A549 cells. miR-15b regulates epithelial-mesenchymal transition (EMT) and cisplatin resistance in vitro and modulates response of lung adenocarcinoma cells to cisplatin in vivo. Further studies identified phosphatidylethanolamine-binding protein 4 (PEBP4) as a direct and functional target of miR-15b. Small-interfering RNA-mediated PEBP4 knockdown revealed similar effects as that of ectopic miR-15b expression, whereas overexpression of PEBP4 attenuated the function of miR-15b in lung adenocarcinoma cells. Increased miR-15b expression was also detected in tumor tissues sampled from lung adenocarcinoma patients treated with cisplatin-based chemotherapy and was proved to be correlated with low expression of PEBP4, decreased sensitivity to cisplatin and poor prognosis. Our results suggest that upregulation of miR-15b could suppress PEBP4 expression and in turn contribute to chemoresistance of lung adenocarcinoma cells to cisplatin.

Targeting microRNAs in epithelial-to-mesenchymal transition-induced cancer stem cells: therapeutic approaches in cancer

INTRODUCTION

Epithelial-to-mesenchymal transition (EMT) is a pathological phenomenon of cancer that confers tumor cells with increased cell motility, invasive and metastatic abilities with the acquisition of 'cancer stem-like cell' (CSC) phenotype. EMT endows tumor cells with intrinsic/acquired resistant phenotype at achievable doses of anticancer drugs and leads to tumor recurrence and progression. Besides the complex network of signaling pathways, microRNAs (miRNAs) are being evolved as a new player in the induction and regulation of EMT.

AREAS COVERED

In this review article, the author has searched the PubMed and Google Scholar electronic databases for original research and review articles to gather current information on the association of EMT-induced CSCs with therapeutic resistance, tumor growth and metastasis, which are believed to be regulated by certain miRNAs.

EXPERT OPINION

This review outlines not only the perspective on selective targeting of EMT-induced CSCs through altered expression of novel miRNAs and/or the use of conventional drugs that affect the levels of critical miRNAs but also the strategies on overcoming the drug resistance by interfering with EMT and modulating its associated pathways in CSCs that can be considered as potential therapeutic approaches toward eradicating the tumor recurrence and metastasis.