Migration And Invasion Enhancer 1 Research Articles

Abstract LB034: First-in-class compounds targeting the MIEN1 signaling pathway: A breakthrough approach for breast and prostate cancer therapy

Abstract We report the identification and complete characterization of first-in-class molecules targeting the MIEN1 signaling pathway in cancer. Migration and invasion enhancer 1 (MIEN1) overexpression characterizes several cancers and facilitates cancer cell migration and invasion. Leveraging conserved ITAM and prenylation motifs within MIEN1, we identified potent anti-cancer peptides. Among them, bioactive peptides LA3IK and RP-7 induced pronounced transcriptomic and protein expression changes at sub-IC50 concentrations. The peptides effectively inhibited genes and proteins driving cancer cell migration, invasion, and EMT pathways, concurrently suppressing EGF-induced NF-kB nuclear translocation in metastatic breast cancer cells. Specifically, peptides targeted the same signal transduction pathway initiated by MIEN1. Molecular docking and circular dichroism spectroscopy indicated the formation of MIEN1-peptide complexes. The third-positioned isoleucine in LA3IK and CVIL motif in RP-7 were crucial for inhibiting breast cancer cell migration. This is evident from the limited migration inhibition observed when MDA-MB-231 cells were treated with scrambled peptides LA3IK-SCR and RP-7-SCR. Additionally, LA3IK and RP-7 effectively suppressed tumor growth in an orthotopic breast cancer model. Notably, mice tolerated high peptide doses of up to 90 mg/Kg well, surpassing significantly lower doses of 5 mg/Kg intravenously (iv) and 30 mg/Kg intraperitoneally (ip) used in both in vivo pharmacokinetic studies and orthotopic mouse model assays. D-isomers of LA3IK and RP-7 showed enhanced anti-cancer activity compared to their L-isomers. D-LA3IK remained stable in mouse plasma for 24 h with 75% remaining, exhibiting superior pharmacokinetic properties over D/L-RP-7. In summary, our findings mark the first report of short peptides based on MIEN1 protein sequence capable of inhibiting cancer signaling pathways, effectively impeding cancer progression both in vitro and in vivo. Citation Format: Amit Kumar Tripathi, Jamboor K. Vishwanatha. First-in-class compounds targeting the MIEN1 signaling pathway: A breakthrough approach for breast and prostate cancer therapy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 2 (Late-Breaking, Clinical Trial, and Invited Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(7_Suppl):Abstract nr LB034.

Short peptides based on the conserved regions of MIEN1 protein exhibit anticancer activity by targeting the MIEN1 signaling pathway

Migration and invasion enhancer 1 (MIEN1) overexpression characterizes several cancers and facilitates cancer cell migration and invasion. Leveraging conserved ITAM and prenylation motifs within MIEN1, we identified potent anti-cancer peptides. Among them, bioactive peptides LA3IK and RP-7 induced pronounced transcriptomic and protein expression changes at sub-IC50 concentrations. The peptides effectively inhibited genes and proteins driving cancer cell migration, invasion, and EMT pathways, concurrently suppressing EGF-induced NF-κB nuclear translocation in metastatic breast cancer cells. Specifically, peptides targeted the same signal transduction pathway initiated by MIEN1. Molecular docking and circular dichroism spectroscopy indicated the formation of MIEN1-peptide complexes. The third-positioned isoleucine in LA3IK and CVIL motif in RP-7 were crucial for inhibiting breast cancer cell migration. This is evident from the limited migration inhibition observed when MDA-MB-231 cells were treated with scrambled peptides LA3IK SCR and RP-7 SCR. Additionally, LA3IK and RP-7 effectively suppressed tumor growth in an orthotopic breast cancer model. Notably, mice tolerated high peptide doses of up to 90 mg/Kg well, surpassing significantly lower doses of 5 mg/Kg intravenously (iv) and 30 mg/Kg intraperitoneally (ip) used in both in vivo pharmacokinetic studies and orthotopic mouse model assays. D-isomers of LA3IK and RP-7 showed enhanced anti-cancer activity compared to their L-isomers. D-LA3IK remained stable in mouse plasma for 24 h with 75% remaining, exhibiting superior pharmacokinetic properties over D/L-RP-7. In summary, our findings mark the first report of short peptides based on MIEN1 protein sequence capable of inhibiting cancer signaling pathways, effectively impeding cancer progression both in vitro and in vivo.

Hemodynamic force dictates endothelial angiogenesis through MIEN1-ERK/MAPK-signaling axis.

It is well-recognized that blood flow at branches and bends of arteries generates disturbed shear stress, which plays a crucial in driving atherosclerosis. Flow-generated fluid shear stress (FSS), as one of the key hemodynamic factors, is appreciated for its critical involvement in regulating angiogenesis to facilitate wound healing and tissue repair. Endothelial cells can directly sense FSS but the mechanobiological mechanism by which they decode different patterns of FSS to trigger angiogenesis remains unclear. In the current study, laminar shear stress (LSS, 15 dyn/cm2) was employed to mimic physiological blood flow, while disturbed shear stress (DSS, ranging from 0.5 ± 4 dyn/cm2) was applied to simulate pathological conditions. The aim was to investigate how these distinct types of blood flow regulated endothelial angiogenesis. Initially, we observed that DSS impaired angiogenesis and downregulated endogenous vascular endothelial growth factor B (VEGFB) expression compared to LSS. We further found that the changes in membrane protein, migration and invasion enhancer 1 (MIEN1) play a role in regulating ERK/MAPK signaling, thereby contributing to endothelial angiogenesis in response to FSS. We also showed the involvement of MIEN1-directed cytoskeleton organization. These findings suggest the significance of shear stress in endothelial angiogenesis, thereby enhancing our understanding of the alterations in angiogenesis that occur during the transition from physiological to pathological blood flow.

HRD1 promotes non-small cell lung carcinoma metastasis by blocking autophagy-mediated MIEN1 degradation

Dysregulation of autophagy has been implicated in the development of many diseases, including cancer. Here, we revealed a novel function of the E3 ubiquitin ligase HRD1 in non-small cell lung carcinoma (NSCLC) metastasis by regulating autophagy. Mechanistically, HRD1 inhibits autophagy by promoting ATG3 ubiquitination and degradation. Additionally, a pro-migratory and invasive factor, MIEN1 (migration and invasion enhancer 1), was found to be autophagically degraded upon HRD1 deficiency. Importantly, expression of both HRD1 and MIEN1 are upregulated and positively correlated in lung tumors. Based on these results, we proposed a novel mechanism of HRD1 function that the degradation of ATG3 protein by HRD1 leads to autophagy inhibition and MIEN1 release, thus promoting NSCLC metastasis. Therefore, our findings provided new insights into the role of HRD1 in NSCLC metastasis and new therapeutic targets for lung cancer treatment.

The circular RNA circ_0030018/miR-136/migration and invasion enhancer 1 (MIEN1) axis promotes the progression of polycystic ovary syndrome

ABSTRACT The abnormal expression of circular RNAs (circRNAs) is associated with the progression of polycystic ovary syndrome (PCOS), which commonly causes infertility in women. In this study, we identified the role of circ_0030018 in PCOS. Quantitative polymerase chain reaction (qPCR) was used to detect the expression levels of circ_0030018, microRNA (miR)-136, and migration and invasion enhancer 1 (MIEN1). Cell counting kit-8 and 5-ethynyl-2’-deoxyuridine assays were performed to analyze the proliferation of KGN cells. Apoptosis was analyzed using fluorescence-activated cell sorting. Transwell assays were performed to measure the migration and invasion abilities of cells. qPCR and Western blotting were used to measure the levels of E-cadherin, N-cadherin, Snail, and vimentin. The correlation of circ_0030018 or MIEN1 expression with miR-136 expression was confirmed via luciferase reporter and RNA pull-down assays. Results showed that circ_0030018 expression was upregulated in patients with PCOS and KGN cells. Knockdown of circ_0030018 suppressed the proliferation, migration, and invasion of cells, while promoting their apoptosis. circ_0030018 sponged miR-136, which targeted MIEN1. Moreover, downregulation of miR-136 abrogated the effects of circ_0030018 silencing, while the overexpression of MIEN1 reversed the miR-136-induced effect on KGN cells. In summary, loss of circ_0030018 delayed the progression of PCOS via the miR-136/MIEN1 axis.

Propofol Ameliorates the Proliferation and Epithelial-Mesenchymal Transition of Hepatoma Carcinoma Cells via Non-Coding RNA Activated by DNA Damage (NORAD)/microRNA (miR)-556-3p/Migration and Invasion Enhancer 1 (MIEN1) Axis.

Propofol has been previously demonstrated to relieve hepatocellular carcinoma (HCC). However, the specific molecular mechanisms mediated by propofol remain to be explored. mRNA or miRNA expression was detected by real-time quantitative polymerase chain reaction (RT-qPCR). Protein expression was determined by Western blot. The interaction between microRNA (miR)-556-3p and long coding RNA non-coding RNA activated by DNA damage (NORAD) or migration and invasion enhancer 1 (MIEN1) was verified by luciferase reporter gene and RNA pull-down assays. Cellular functions were determined using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetra-zolium bromide (MTT), 5-ethynyl-2'-deoxyuridine (EdU), and Transwell assays. Propofol notably suppressed the proliferation and EMT of Hep3B and SNU449 cell lines. NORAD was overexpressed in the HCC tissues and cells, while propofol decreased NORAD levels in the HCC cells. Conversely, overexpression of NORAD partially restored malignant behaviors of the HCC cells and abolished the effects of propofol. Additionally, NORAD sponged miR-556-3p to upregulate MIEN1. However, the knockdown of MIEN1 suppressed the proliferation and EMT of HCC cells. Propofol inhibited HCC cell proliferation and EMT progress via NORAD/miR-556-3p/MIEN1 axis. These data provided a potent prognosis and diagnostic marker for HCC and supplemented the underlying mechanism of propofol-induced anti-tumor effects.

MiR-124-5p Inhibits the Progression of Gastric Cancer by Targeting MIEN1.

Objective:To observe the effect of miR-124-5p on progression of gastric cancer (GC) and explore the targeting mechanism.Methods:After collecting the specimens, we used real-time fluorescence quantitative PCR to detect the miR-124-5p level of GC tissue and corresponding adjacent tissue. Then MTT test and scratch wound-healing assay were hired to evaluate the influence of miR-124-5p in GC cell (SGC-803 and SGC7901) migration and proliferation ability. The binding of miR-124-5p to migration and invasion enhancer 1 (MIEN1) was detected through dual luciferase reporter gene experiment and western blot was utilized to assay the protein level of MIEN1.Results:Compared with adjacent tissues, miR-124-5p level in GC tissues was lower significantly. MiR-124-5p mimic inhibited the metastasis and proliferation ability of SGC7901 cells and miR-124-5p inhibitor promoted the migration and proliferation ability of SGC803 cells. In addition, miR-124-5p targeted MIEN1 and negatively modulated the MIEN1 expression in SGC-803 and SGC7901 cells. Silencing MIEN1 negatively regulated the metastasis and proliferation ability of SGC7901 cells.Conclusion:MiR-124-5p inhibited the GC cell proliferation and metastasis phenotypes through MIEN1, which probably becomes a novel molecular target for clinical GC treatment.

Migration and Invasion Enhancer 1 Is an NF-ĸB-Inducing Gene Enhancing the Cell Proliferation and Invasion Ability of Human Prostate Carcinoma Cells In Vitro and In Vivo.

Migration and invasion enhancer 1 (MIEN1) is a membrane-anchored protein and exists in various cancerous tissues. However, the roles of MIEN1 in prostate cancer have not yet been clearly addressed. We determined the expression, biological functions, and regulatory mechanisms of MIEN1 in the prostate. The results of immunohistochemical analysis indicated that MIEN1 was expressed specifically in epithelial cells and significantly higher in adenocarcinoma as compared to in normal tissues. MIEN1 enhanced in vitro cell proliferation, invasion, and in vivo tumorigenesis. Meanwhile, MIEN1 attenuated cisplatin-induced apoptosis in PC-3 cells. Overexpression of NF-ĸB-inducing kinase (NIK) enhanced MIEN1 expression, while overexpression of NF-ĸB inhibitor α (IĸBα) blocked MIEN1 expression in PC-3 cells. In prostate carcinoma cells, MIEN1 provoked Akt phosphorylation; moreover, MIEN1 downregulated N-myc downstream regulated 1 (NDRG1) but upregulated interleukin-6 (IL-6) gene expression. MK2206, an Akt inhibitor, impeded the modulation of MIEN1 on NDRG1 and IL-6 expressions. Our studies suggest that MIEN1 is an NF-ĸB downstream oncogene in the human prostate. Accordingly, the modulation of Akt signaling in the gene expressions of NDRG1 and IL-6 may account for the functions of MIEN1 in cell proliferation, invasion, and tumorigenesis in prostate carcinoma cells.

Emerging Role of Migration and Invasion Enhancer 1 (MIEN1) in Cancer Progression and Metastasis.

Tumor metastasis is a sequential event accounting for numerous cancer-related fatalities worldwide. The process of metastasis serially involves invasion, intravasation, extravasation, and tumor growth at the secondary site. Migration and invasion enhancer 1 (MIEN1) is a membrane associated protein overexpressed in various human cancers. Biological activity of MIEN1 is driven by geranylgeranyltransferase-I mediated prenylation at CAAX motif and methylation of the prenylated protein that anchors MIEN1 into the cellular membrane. Post-translationally modified MIEN1 interacts with Syk kinase and Annexin A2 protein; polymerizes G-actin and stabilizes F-actin filament; induces focal adhesion kinase phosphorylation and decrease cofilin phosphorylation implicated in both invasion and metastasis of different cancer types. In the present review, we discuss the structure, function, and involvement of MIEN1 in cancer progression. We also highlight the future prospects of MIEN1 as an emerging molecule and novel target in cancer cell invasion and metastasis.

Downregulation of miR‑136 promotes the progression of osteosarcoma and is associated with the prognosis of patients with osteosarcoma

Osteosarcoma (OS) is the most common bone tumor in children and young adults, and is an aggressive tumor with poor prognosis. MicroRNAs (miRNAs) are aberrantly expressed in various types of cancer, and contribute to cancer tumorigenesis and progression. In the present study, the potential prognostic value and biological function of miRNA-136 (miR-136) in OS was investigated. Reverse transcription-quantitative polymerase chain reaction analysis was used to evaluate the expression of miR-136 in OS tissues and cell lines. Kaplan-Meier survival analysis and Cox regression analysis were conducted to investigate the prognostic significance of miR-136. Various in vitro cell based assays were used to evaluate the effects of miR-136 on the biological behavior of OS cells. A luciferase assay was performed to determine the key miR-136 targets associated with OS. The expression of miR-136 was significantly downregulated in osteosarcoma tissues and cells compared with the normal controls (all P<0.05). Decreased miR-136 expression was significantly associated with Enneking staging (P=0.030) and distant metastasis (P=0.016). Decreased miR-136 expression in patients was associated with shorter overall survival compared with patients with increased expression levels (log-rank test; P<0.05). The expression of miR-136 was indicated as an independent prognostic factor for the patients (hazard ratio=0.496; 95% confidence interval=0.250-0.987; P=0.046). MTT, transwell and Matrigel assays demonstrated that upregulation of miR-136 decreased proliferation, migration and invasion of OS cells. Bioinformatics and luciferase assays demonstrated that migration and invasion enhancer 1 (MIEN1) is a direct target of miR-136. Together, the results suggested that miR-136 functions as a tumor suppressor gene to regulate proliferation, migration and invasion of OS cells. MIEN1 was a potential target of miR-136. Additionally, miR-136 may serve as a prognostic biomarker for OS.

Abstract 5812: MIEN1 promotes breast cancer cell migration and invasion by regulating cytoskeletal dynamics via focal adhesion kinase and N-WASP

Abstract Short Description: Migration and invasion enhancer 1 (MIEN1) is an important regulator of cell migration and invasion. MIEN1 overexpression represents an oncogenic event that promotes tumor cell dissemination and metastasis. The underlying mechanism by which MIEN1 regulates migration and invasion has yet to be deciphered. Methods: Immunofluorescence, actin polymerization, Immunoprecipitation, migration, invasion, and adhesion assays were performed using breast cancer cell lines, MDA-MB-231 and MCF10CA1a to investigate the mechanisms by which MIEN1 potentiates cell motility. Results: Our results show that MIEN1 acts as a cytoskeletal-signaling adapter protein to drive breast cancer cell migration. Knockdown of MIEN1 led to the loss of actin-protrusive structures whereas the overexpression of MIEN1 resulted in rich and thick membrane extensions. Knockdown of MIEN1 also decreased the cell-substratum adhesion, suggesting a role for MIEN1 in actin cytoskeletal dynamics. Our results show that MIEN1 supports the transition of G-actin to F-actin polymerization and stabilizes F-actin polymers. Additionally, MIEN1 promotes cellular adhesion and actin dynamics by inducing phosphorylation of FAK at Tyr-925 and reducing phosphorylation of cofilin at Ser-3, which results in breast cancer cell migration. Furthermore, we found that MIEN1 associates with cytoskeletal proteins involved in motility processes. Conclusion: Our results show that MIEN1 plays an essential role in maintaining the plasticity of the dynamic membrane-associated actin cytoskeleton, which leads to an increase in cell motility. Hence, targeting MIEN1 might represent a promising means to prevent breast tumor metastasis. Note: This abstract was not presented at the meeting. Citation Format: Pankaj Chaudhary, Marilyne Kpetemey, Timothy Van Treuren, Jamboor K. Vishwanatha. MIEN1 promotes breast cancer cell migration and invasion by regulating cytoskeletal dynamics via focal adhesion kinase and N-WASP [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 5812. doi:10.1158/1538-7445.AM2017-5812

Migration and invasion enhancer 1 (MIEN1) is overexpressed in breast cancer and is a potential new therapeutic molecular target.

Migration and invasion enhancer 1 (MIEN1) is a membrane-anchored protein that is highly expressed in various types of cancer, and is correlated with the PI3K/AKT pathway. The aim of this study was to investigate the expression of MIEN1 and its clinical pathological significance in breast cancer. We used immunohistochemical staining to examine the expression of MIEN1 in 40 samples of human breast cancer tissue and 10 samples taken from regions adjacent to normal breast tissue. The rate of detection of MIEN1 protein was 67.5%, which was significantly higher than that in adjacent non-cancerous breast tissue (0%, P < 0.05). The expression of MIEN1 correlated with age, World Health Organization grade, and lymph node metastasis, but not with tumor size or family history of cancer. Kaplan-Meier survival analysis showed that patients with positive MIEN1 protein expression had a lower overall survival rate than patients who did not express MIEN1. Downregulation of MIEN1 suppressed the expression of matrix metallopeptidase 9 by downregulating the expression of protein kinase B (also known as AKT) in breast cancer cells. Our results indicate that MIEN1 overexpression may facilitate migration and invasion in breast cancer, and MIEN1 is a potential molecular target for cancer chemotherapy.

MIEN1 is tightly regulated by SINE Alu methylation in its promoter.

Migration and invasion enhancer 1 (MIEN1) is a novel gene involved in prostate cancer progression by enhancing prostate cancer cell migration and invasion. DNA methylation, an important epigenetic regulation, is one of the most widely altered mechanisms in prostate cancer. This phenomenon frames the basis to study the DNA methylation patterns in the promoter region of MIEN1. Bisulfite pyrosequencing demonstrates the MIEN1 promoter contains a short interspersed nuclear Alu element (SINE Alu) repeat sequence. Validation of methylation inhibition on MIEN1 was performed using nucleoside analogs and non-nucleoside inhibitors and resulted in an increase in both MIEN1 RNA and protein in normal cells. MIEN1 mRNA and protein increases upon inhibition of individual DNA methyltransferases using RNA interference technologies. Furthermore, dual luciferase reporter assays, in silico analysis, and chromatin immunoprecipitation assays identified a sequence upstream of the transcription start site that has a site for binding of the USF transcription factors. These results suggest the MIEN1 promoter has a SINE Alu region that is hypermethylated in normal cells leading to repression of the gene. In cancer, the hypomethylation of a part of this repeat, in addition to the binding of USF, results in MIEN1 expression.

MIEN1 drives breast tumor cell migration by regulating cytoskeletal-focal adhesion dynamics.

Migration and invasion enhancer 1 (MIEN1) is an important regulator of cell migration and invasion. MIEN1 overexpression represents an oncogenic event that promotes tumor cell dissemination and metastasis. The underlying mechanism by which MIEN1 regulates migration and invasion has yet to be deciphered. Here, we demonstrate that MIEN1 acts as a cytoskeletal-signaling adapter protein to drive breast cancer cell migration. MIEN1 localization is concentrated underneath the actin-enriched protrusive structures of the migrating breast cancer cells. Depletion of MIEN1 led to the loss of actin-protrusive structures whereas the over-expression of MIEN1 resulted in rich and thick membrane extensions. Knockdown of MIEN1 also decreased the cell-substratum adhesion, suggesting a role for MIEN1 in actin cytoskeletal dynamics. Our results show that MIEN1 supports the transition of G-actin to F-actin polymerization and stabilizes F-actin polymers. Additionally, MIEN1 promotes cellular adhesion and actin dynamics by inducing phosphorylation of FAK at Tyr-925 and reducing phosphorylation of cofilin at Ser-3, which results in breast cancer cell migration. Collectively, our data show that MIEN1 plays an essential role in maintaining the plasticity of the dynamic membrane-associated actin cytoskeleton, which leads to an increase in cell motility. Hence, targeting MIEN1 might represent a promising means to prevent breast tumor metastasis.

MicroRNA-26b suppresses the metastasis of non-small cell lung cancer by targeting MIEN1 via NF-κB/MMP-9/VEGF pathways

MicroRNAs (miRNAs) are involved in tumor initiation and progression. MiR-26b was reported to be significantly downregulated in non-small cell lung cancer (NSCLC). However, the underlying mechanisms of miR-26b involvement in the development and progression of NSCLC remains poorly understood. In the present study, we report that miR-26b suppresses cell metastasis in NSCLC through targeting migration and invasion enhancer 1 (MIEN1). We found that miR-26b was significantly downregulated and MIEN1 was significantly upregulated in both NSCLC tissues and cells lines. The expression levels of miR-26b were negatively related to those of MIEN1 mRNA in clinical NSCLC tissues. Furthermore, MIEN1 was confirmed to be a direct target of miR-26b by dual-luciferase reporter assay and MIEN1 expression was downregulated by miR-26b in NSCLC cells. In terms of function, transwell and wound healing assays demonstrated that the miR-26b remarkably inhibited invasion and migration of NSCLC cells, which was simulated by siRNA knockdown of MIEN1 and reversed by pcDNA/MIEN1 overexpression of MIEN1. Finally, we found that miR-26b could regulate NF-κB/MMP-9/VEGF pathway in NSCLC cells. In conclusion, this study revealed that miR-26b suppresses NSCLC metastasis by targeting MIEN1 via NF-κB/MMP-9/VEGF pathways, implicating a potential prognostic biomarker and therapeutic target for NSCLC treatment.

Abstract 520: MIEN1 drives breast cancer invasion by regulating cytoskeletal dynamics

Abstract Introduction: The emergence of metastases remains the primary cause of cancer mortality and morbidity. Active migration of tumour cells is a prerequisite for tumor-cell invasion and metastasis. We identified Migration and Invasion Enhancer 1(MIEN1) as a novel promoter of cell migration/invasion. Previously known as C35, C17orf37, RDX12 and MGC14832, MIEN1 is a novel gene located in the chromosomal region 17q12-21. While absent or low in normal tissues, MIEN1 is abundantly expressed in multiple cancers including breast carcinomas. A membrane-bound signaling adaptor, MIEN1 localizes to the leading edge of migrating cells and promotes migration and invasion by increasing filopodium formation. While MIEN1 is shown to promote motility through filopodia formation, little is known on the mechanisms by which MIEN1 influence the actin cytoskeleton. Exploring underlying mechanisms, we show that MIEN1 associates with the actin cytokeleton during motility and directly influence actin polymerization. Methods: We performed immunofluorescence, migration and invasion assays using breast cancer cell lines, MDA-MB 231 and MCF10CA1a to investigate the mechanisms by which MIEN1 potentiates cell motility. Results: Ablation of MIEN1 inhibited cell migration, cell adhesion and altered the phosphorylation status of motility markers. Immunofluorescence staining with FITC- conjugated-phalladoin confirmed that alteration of MIEN1 expression leads to reconfiguration of the actin cytoskeleton in breast cancer cells. Furthermore we found that MIEN1 associates with cytoskeletal proteins involved in motility processes. Conclusion: Our results show that MIEN1 is a critical regulator of cell migration and invasion. The importance of MIEN1 in tumor cell dissemination is well established; understanding the molecular mechanisms aiding the processes involved will enable the design of novel and effective treatments for metastatic tumors. Citation Format: Marilyne Kpetemey, Jamboor Vishwanatha. MIEN1 drives breast cancer invasion by regulating cytoskeletal dynamics. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 520. doi:10.1158/1538-7445.AM2015-520

MIEN1 promotes oral cancer progression and implicates poor overall survival

Oral squamous cell carcinoma is a highly malignant tumor with the potential to invade local and distant sites and promote lymph node metastasis. Major players underlying the molecular mechanisms behind tumor progression are yet to be fully explored. Migration and invasion enhancer 1 (MIEN1), a novel protein overexpressed in various cancers, facilitates cell migration and invasion. In the present study we investigated the expression and role of MIEN1 in oral cancer progression using an in vitro model, patient derived oral tissues and existing TCGA data. Expression analysis using immortalized normal and cancer cells demonstrated increased expression of MIEN1 in cancer. Assays performed after MIEN1 knockdown in OSC-2 cells showed decreased migration, invasion and filopodia formation; while MIEN1 overexpression in DOK cells increased these characteristics and also up-regulated some Akt/NF-κB effectors, thereby suggesting an important role for MIEN1 in oral cancer progression. Immunohistochemical staining and analyses of oral tissue specimens, collected from patients over multiple visits, revealed significantly more staining in severe dysplasia and squamous cell carcinoma compared to mildly dysplastic or hyperplastic tissues. Finally, this was corroborated with the TCGA dataset, where MIEN1 expression was not only higher in intermediate and high grade cancer with significantly lower survival but also correlated with smoking. In summary, we demonstrate that MIEN1 expression not only positively correlates with oral cancer progression but also seems to be a critical molecular determinant in migration and invasion of oral cancer cells, thereby, playing a possible role in their metastatic dissemination.

MicroRNA-940 suppresses prostate cancer migration and invasion by regulating MIEN1.

BackgroundMicroRNAs (miRNAs) are crucial molecules that regulate gene expression and hence pathways that are key to prostate cancer progression. These non-coding RNAs are highly deregulated in prostate cancer thus facilitating progression of the disease. Among the many genes that have gained importance in this disease, Migration and invasion enhancer 1 (MIEN1), a novel gene located next to HER2/neu in the 17q12 amplicon of the human chromosome, has been shown to enhance prostate cancer cell migration and invasion, two key processes in cancer progression. MIEN1 is differentially expressed between normal and cancer cells and tissues. Understanding the regulation of MIEN1 by microRNA may enable development of better targeting strategies.MethodsThe miRNAs that could target MIEN1 were predicted by in silico algorithms and microarray analysis. The validation for miRNA expression was performed by qPCR and northern blotting in cells and by in situ hybridization in tissues. MIEN1 and levels of other molecules upon miRNA regulation was determined by Western blotting, qPCR, and immunofluorescence. The functional effects of miRNA on cells were determined by wound healing cell migration, Boyden chamber cell invasion, clonal and colony formation assays. For knockdown or overexpression of the miRNA or overexpression of MIEN1 3′UTR, cells were transfected with the oligomiRs and plasmids, respectively.ResultsA novel miRNA, hsa-miR-940 (miR-940), identified and validated to be highly expressed in immortalized normal cells compared to cancer cells, is a regulator of MIEN1. Analysis of human prostate tumors and their matched normal tissues confirmed that miR-940 is highly expressed in the normal tissues compared to its low to negligible expression in the tumors. While MIEN1 is a direct target of miR-940, miR-940 alters MIEN1 RNA, in a quantity as well as cell dependent context, along with altering its downstream effectors. The miR-940 inhibited migratory and invasive potential of cells, attenuated their anchorage-independent growth ability, and increased E-cadherin expression, implicating its role in mesenchymal-to-epithelial transition (MET).ConclusionsThese results, for the first time, implicate miR-940, a regulator of MIEN1, as a promising novel diagnostic and prognostic tool for prostate cancer.Electronic supplementary materialThe online version of this article (doi:10.1186/1476-4598-13-250) contains supplementary material, which is available to authorized users.

MIEN1 (migration and invasion enhancer 1)

Review on MIEN1 (migration and invasion enhancer 1), with data on DNA, on the protein encoded, and where the gene is implicated.