MiRNA-101 inhibits breast cancer growth and metastasis by targeting CX chemokine receptor 7

Enhancing Therapeutic Efficacy in Cancer Treatment: Integrating Nanomedicine with Autophagy Inhibition Strategies

The complicated stepwise lysosomal degradation process known as autophagy is in charge of destroying and eliminating damaged organelles and defective cytoplasmic components. This mechanism promotes metabolic adaptability and nutrition recycling. Autophagy functions as a quality control mechanism in cells that support homeostasis and redox balance under normal circumstances. However, the role of autophagy in cancer is controversial because, mostly depending on the stage of the tumor, it may either suppress or support the disease. While autophagy delays the onset of tumors and slows the dissemination of cancer in the early stages of tumorigenesis, numerous studies demonstrate that autophagy promotes the development and spread of tumors as well as the evolution and development of resistance to several anticancer drugs in advanced cancer stages. In this Review, we primarily emphasize the therapeutic role of autophagy inhibition in improving the treatment of multiple cancers and give a broad overview of how its inhibition modulates cancer responses. There have been various attempts to inhibit autophagy, including the use of autophagy inhibitor drugs, gene silencing therapy (RNA interference), and nanoparticles. In this Review, all these topics are thoroughly covered and illustrated by recent studies and field investigations.

New insights of miRNA molecular mechanisms in breast cancer brain metastasis and therapeutic targets

Brain metastases in breast cancer (BC) patients are often associated with a poor prognosis. Recent studies have uncovered the critical roles of miRNAs in the initiation and progression of BC brain metastasis, highlighting the disease's underlying molecular pathways. miRNA-181c, miRNA-10b, and miRNA-21, for example, are all overexpressed in BC patients. It has been shown that these three miRNAs help tumors grow and metastasize by targeting genes that control how cells work. On the other hand, miRNA-26b5p, miRNA-7, and miRNA-1013p are all downregulated in BC brain metastasis patients. They act as tumor suppressors by controlling the expression of genes related to cell adhesion, angiogenesis, and invasion. Therapeutic miRNA targeting has considerable promise in treating BC brain metastases. Several strategies have been proposed to modulate miRNA expression, including miRNA-Mimics, antagomirs, and small molecule inhibitors of miRNA biogenesis. This review discusses the aberrant expression of miRNAs and metastatic pathways that lead to the spread of BC cells to the brain. It also explores miRNA therapeutic target molecular mechanisms and BC brain metastasis challenges with advanced strategies. The targeting of certain miRNAs opens a new door for the development of novel therapeutic approaches for this devastating disease.

Circulating miRNAs signature on breast cancer: the MCC-Spain project

PURPOSE

To build models combining circulating microRNAs (miRNAs) able to identify women with breast cancer as well as different types of breast cancer, when comparing with controls without breast cancer.

METHOD

miRNAs analysis was performed in two phases: screening phase, with a total n = 40 (10 controls and 30 BC cases) analyzed by Next Generation Sequencing, and validation phase, which included 131 controls and 269 cases. For this second phase, the miRNAs were selected combining the screening phase results and a revision of the literature. They were quantified using RT-PCR. Models were built using logistic regression with LASSO penalization.

RESULTS

The model for all cases included seven miRNAs (miR-423-3p, miR-139-5p, miR-324-5p, miR-1299, miR-101-3p, miR-186-5p and miR-29a-3p); which had an area under the ROC curve of 0.73. The model for cases diagnosed via screening only took in one miRNA (miR-101-3p); the area under the ROC curve was 0.63. The model for disease-free cases in the follow-up had five miRNAs (miR-101-3p, miR-186-5p, miR-423-3p, miR-142-3p and miR-1299) and the area under the ROC curve was 0.73. Finally, the model for cases with active disease in the follow-up contained six miRNAs (miR-101-3p, miR-423-3p, miR-139-5p, miR-1307-3p, miR-331-3p and miR-21-3p) and its area under the ROC curve was 0.82.

CONCLUSION

We present four models involving eleven miRNAs to differentiate healthy controls from different types of BC cases. Our models scarcely overlap with those previously reported.

MiR-297 inhibits tumour progression of liver cancer by targeting PTBP3

Whereas increasing evidences demonstrate that miR-297 contributes to the tumour development and progression, the role of miR-297 and its underlying molecular mechanisms in hepatocellular carcinoma (HCC) was still unclear. Here, we reported that the expression of miR-297 increased significantly in hepG2 cells after the treatment of the conditioned medium of human amniotic epithelial cells(hAECs) which can inhibit the proliferation and migration of hepG2. And the overexpression of miR-297 inhibits the cell proliferation, migration and invasion of HCC cell lines in vitro and suppressed the tumorigenesis of HCC in vivo. Polypyrimidine tract-binding protein 3 (PTBP3) was identified as a direct target gene of miR-297 in HCC cell lines, and mediated the function of miR-297 in HCC cells. In clinical samples, miR-297 levels have a tendency to decrease, but there are no statistically significant differences. Furthermore, in vitro cell experiments confirmed that overexpression of miR-297 could inhibit the PI3K/AKT signaling pathway by down-regulating PTBP3 expression, thereby inhibiting the proliferation, migration and invasion of HCC cells. In conclusion, our results revealed that miR-297 could down-regulate the expression of PTBP3 and inhibit the activation of PI3K/AKT signaling pathway, thereby preventing HCC growth, migration and invasion.

miRNAs role in glioblastoma pathogenesis and targeted therapy: Signaling pathways interplay

High mortality and morbidity rates and variable clinical behavior are hallmarks of glioblastoma (GBM), the most common and aggressive primary malignant brain tumor. Patients with GBM often have a dismal outlook, even after undergoing surgery, postoperative radiation, and chemotherapy, which has fueled the search for specific targets to provide new insights into the development of contemporary therapies. The ability of microRNAs (miRNAs/miRs) to posttranscriptionally regulate the expression of various genes and silence many target genes involved in cell proliferation, cell cycle, apoptosis, invasion, angiogenesis, stem cell behavior and chemo- and radiotherapy resistance makes them promising candidates as prognostic biomarkers and therapeutic targets or factors to advance GBM therapeutics. Hence, this review is like a crash course in GBM and how miRNAs related to GBM. Here, we will outline the miRNAs whose role in the development of GBM has been established by recent in vitro or in vivo research. Moreover, we will provide a summary of the state of knowledge regarding oncomiRs and tumor suppressor (TS) miRNAs in relation to GBM with an emphasis on their potential applications as prognostic biomarkers and therapeutic targets.

Selective Elimination of Senescent Fibroblasts by Targeting the Cell Surface Protein ACKR3

The accumulation of senescent cells in aging tissues is associated with age-related diseases and functional decline. Thus, senolysis, a therapy aimed at rejuvenation by removing senescent cells from the body, is being developed. However, this therapy requires the identification of membrane surface antigens that are specifically expressed on senescent cells for their selective elimination. We showed that atypical chemokine receptor 3 (ACKR3), a receptor of the CXC motif chemokine 12 (CXCL12) implicated in cancer, inflammation, and cardiovascular disorders, is selectively expressed on the surface of senescent human fibroblasts but not on proliferating cells. Importantly, the differential presence of ACKR3 enabled the isolation of senescent cells by flow cytometry using anti-ACKR3 antibodies. Furthermore, antibody-dependent cellular cytotoxicity assays revealed that cell surface ACKR3 preferentially sensitizes senescent but not dividing fibroblasts to cell injury by natural killer cells. Conclusively, the selective expression of ACKR3 on the surface of senescent cells allows the preferential elimination of senescent cells. These results might contribute to the future development of novel senolysis approaches.

Blood Circulating Non-Coding RNAs for the Clinical Management of Triple-Negative Breast Cancer

Triple negative breast cancer (TNBC) represents the most aggressive subtype of breast cancer, and is related to unfavorable prognosis and limited treatment strategies. Currently, there is a lack of reliable biomarkers allowing for the clinical management of TNBC. This is probably caused by a complex molecular background, leading to the development and establishment of a unique tumor phenotype. Recent studies have reported non-coding RNAs (ncRNAs) not only as the most promising class of molecular agents with a high applicability to manage human cancers, including TNBC, but also as robust and non-invasive biomarkers that are able to be monitored in blood circulation, with the application of liquid biopsy. There is a lack of papers discussing the role of blood-circulating ncRNAs as diagnostic, predictive, and prognostic biomarkers for TNBC. In this paper, we summarized the available literature reports on the utility of blood-circulating ncRNAs for TNBC management. Additionally, we supplemented this review by bioinformatics analysis, for better understanding of the role of ncRNAs' machinery in the development of a unique TNBC phenotype.

Effects of SDF-1/CXCR7 on the Migration, Invasion and Epithelial-Mesenchymal Transition of Gastric Cancer Cells

We found that SDF-1/CXCR7 axis played an important role in the growth and proliferation of gastric cancer in the previous studies. The objectives of this study were to explore the effects of SDF-1/CXCR7 on the metastatic ability of gastric cancer cells and the possible mechanisms. CXCR7 expression in SGC-7901 gastric cancer cells was stably knocked down via lentiviral vectors. The cell migration and invasion abilities were detected by transwell migration and invasion assays. The expressions of matrix metalloproteinase 2 (MMP-2), MMP-9, vascular endothelial growth factor (VEGF), epithelial-mesenchymal transition (EMT) markers and Akt phosphorylation were detected with real-time PCR and/or western blot. We found that SDF-1 markedly enhanced the migration and invasion abilities of SGC-7901 gastric cancer cells; CXCR7 knockdown inhibited these effects. SDF-1/CXCR7 increased the expressions of MMP-2, MMP-9 and VEGF. SDF-1/CXCR7 also downregulated E-cadherin expression but upregulated N-cadherin, vimentin and Snail expressions, suggesting that SDF-1/CXCR7 could promote the development of EMT in gastric cancer cells. Furthermore, SDF-1/CXCR7 could promote Akt phosphorylation. Our results indicated that SDF-1/CXCR7 enhanced the migration, invasion and EMT of gastric cancer cells and thus CXCR7 supression may be a strategy for inhibiting gastric cancer metastasis.

Preclinical Imaging Evaluation of miRNAs' Delivery and Effects in Breast Cancer Mouse Models: A Systematic Review

BACKGROUND

We have conducted a systematic review focusing on the advancements in preclinical molecular imaging to study the delivery and therapeutic efficacy of miRNAs in mouse models of breast cancer.

METHODS

A systematic review of English articles published in peer-reviewed journals using PubMed, EMBASE, BIOSIS™ and Scopus was performed. Search terms included breast cancer, mouse, mice, microRNA(s) and miRNA(s).

RESULTS

From a total of 2073 records, our final data extraction was from 114 manuscripts. The most frequently used murine genetic background was Balb/C (46.7%). The most frequently used model was the IV metastatic model (46.8%), which was obtained via intravenous injection (68.9%) in the tail vein. Bioluminescence was the most used frequently used tool (64%), and was used as a surrogate for tumor growth for efficacy treatment or for the evaluation of tumorigenicity in miRNA-transfected cells (29.9%); for tracking, evaluation of engraftment and for response to therapy in metastatic models (50.6%).

CONCLUSIONS

This review provides a systematic and focused analysis of all the information available and related to the imaging protocols with which to test miRNA therapy in an in vivo mice model of breast cancer, and has the purpose of providing an important tool to suggest the best preclinical imaging protocol based on available evidence.

Is the regulation by miRNAs of NTPDase1 and ecto-5'-nucleotidase genes involved with the different profiles of breast cancer subtypes?

Breast cancer (BC) is a public health problem worldwide, causing suffering and premature death among women. As a heterogeneous disease, BC-specific diagnosis and treatment are challenging. Ectonucleotidases are related to tumor development and their expression may vary among BC. miRNAs may participate in epigenetic events and may regulate ectonucleotidases in BC. This study aimed to evaluate the expression of ectonucleotidases according to BC subtypes and to predict if there is post-transcriptional regulation of them by miRNAs. MCF 10A (non-tumorigenic), MCF7 (luminal BC), and MDA-MB-231 (triple-negative BC - TNBC) breast cell lines were used and ENTPD1 (the gene encoding for NTPDase1) and NT5E (the gene encoding for ecto-5'-nucleotidase) gene expression was determined. Interestingly, the expression of ENTPD1 was only observed in MCF7 and NT5E was lower in MCF7 compared to MDA-MB-231 cell line. ATP, ADP, and AMP hydrolysis were observed on the surface of all cell lines, being higher in MDA-MB-231. Like qPCR, the activity of AMP hydrolysis was also lower in the MCF7 cells, which may represent a striking feature of this BC subtype. In silico analyses confirmed that the miRNAs miR-101-3p, miR-141-3p, and miR-340-5p were higher expressed in MCF7 cells and targeted NT5E mRNA. Altogether, data suggest that the regulation of NT5E by miRNAs in MCF7 lineage may direct the molecular profile of luminal BC. Thus, we suggest that the roles of ecto-5'-nucleotidase and the aforementioned miRNAs must be unraveled in TNBC to be possibly defined as diagnostic and therapeutic targets.

Let-7a-5p, miR-100-5p, miR-101-3p, and miR-199a-3p Hyperexpression as Potential Predictive Biomarkers in Early Breast Cancer Patients

BACKGROUND

The aim of this study is to identify miRNAs able to predict the outcomes in breast cancer patients after neoadjuvant chemotherapy (NAC).

PATIENTS AND METHODS

We retrospectively analyzed 24 patients receiving NAC and not reaching pathologic complete response (pCR). miRNAs were analyzed using an Illumina Next-Generation-Sequencing (NGS) system.

RESULTS

Event-free survival (EFS) and overall survival (OS) were significantly higher in patients with up-regulation of let-7a-5p (EFS p = 0.006; OS p = 0.0001), mirR-100-5p (EFS s p = 0.01; OS p = 0.03), miR-101-3p (EFS p = 0.05; OS p = 0.01), and miR-199a-3p (EFS p = 0.02; OS p = 0.01) in post-NAC samples, independently from breast cancer subtypes. At multivariate analysis, only let-7a-5p was significantly associated with EFS (p = 0.009) and OS (p = 0.0008).

CONCLUSION

Up-regulation of the above miRNAs could represent biomarkers in breast cancer.

MicroRNA and cyclooxygenase-2 in breast cancer

Cancer remains a major public health problem worldwide and the latest statistics show that breast cancer (BC) is among the most frequent in women. MicroRNAs (miRNAs; miRs) and cyclooxygenase-2 (COX-2) are new diagnostic and therapeutic biomarkers for monitoring BC. COX-2 is a prominent tumor-associated inflammatory factor highly expressed in human tumor cells, including BC. Expression of COX-2 contributes to tumor growth, metastasis and recurrence. MiRs are a group of short (~22 nucleotides), noncoding regulatory RNAs that downregulate gene expression post-transcriptionally and play vital roles in regulating cancer development and progression. Interestingly, there are a group of miRNAs differentially expressed in breast tumor tissue. Understanding the pathway linking miRNAs to COX-2 can provide novel insight for suppressing COX-2 expression via gene silencing thereby leading to the development of selective miRNA inhibitors. Further research can also reveal key intermediate players and their potential as therapeutic targets. Given the association between different miRNAs and COX-2 expression in BC, this review presents a comprehensive overview of the current literature concerning how miRNAs and COX-2 signaling interact in BC progression.

Single nucleotide polymorphisms in microRNAs action as biomarkers for breast cancer

MicroRNAs (miRNAs) have been recently described as small noncoding RNAs that are involved in numerous crucial physiological processes, such as cell cycles, differentiation, development, and metabolism. Thus, dysregulation of these molecules could lead to several severe disorders, including breast cancer (BC). Ongoing investigations in malignant growth diagnostics have distinguished miRNAs as promising disease biomarkers. As with any other mRNAs, single nucleotide polymorphisms (SNPs) in DNA sequence encoding for miRNA (miR-SNPs) indeed lead to potential changes in the function of miRNA. In this study, miR-SNPs located in different miRNA sequence regions, which have been associated with BC in different ways, and the potential mechanisms of how these miR-SNPs develop the risk of the disease were discussed.

Loss of miR-101-3p Promotes Transmigration of Metastatic Breast Cancer Cells through the Brain Endothelium by Inducing COX-2/MMP1 Signaling

Brain metastases represent one of the incurable end stages in breast cancer (BC). Developing effective or preventive treatments is hampered by a lack of knowledge on the molecular mechanisms driving brain metastasis. Transmigration of BC cells through the brain endothelium is a key event in the pathogenesis of brain metastasis. In this study, we identified miR-101-3p as a critical micro-RNA able to reduce transmigration of BC cells through the brain endothelium. Our results revealed that miR-101-3p expression is downregulated in brain metastatic BC cells compared to less invasive variants, and varies inversely compared to the brain metastatic propensity of BC cells. Using a loss-and-gain of function approach, we found that miR-101-3p downregulation increased transmigration of BC cells through the brain endothelium in vitro by inducing COX-2 expression in cancer cells, whereas ectopic restoration of miR-101-3p exerted a metastasis-reducing effect. In regulatory experiments, we found that miR-101-3p mediated its effect by modulating COX-2-MMP1 signaling capable of degrading the inter-endothelial junctions (claudin-5 and VE-cadherin), key components of the brain endothelium. These findings suggest that miR-101-3p plays a critical role in the transmigration of breast cancer cells through the brain endothelium by modulating the COX-2-MMP1 signaling and thus may serve as a therapeutic target that can be exploited to prevent or suppress brain metastasis in human breast cancer.

Chemokines and chemokine receptors: A new strategy for breast cancer therapy

Chemokines and chemokine receptors not only participate in the development of tissue differentiation, hematopoiesis, inflammation, and immune regulation but also play an important role in the process of tumor development. The role of chemokines and chemokine receptors in tumors has been emphasized in recent years. More and more studies have shown that chemokines and chemokine receptors are closely related to the occurrence, angiogenesis, metastasis, drug resistance, and immunity of breast cancer. Here, we review recent progression on the roles of chemokines and chemokine receptors in breast cancer, and discuss the possible mechanism in breast cancer that might facilitate the development of new therapies by targeting chemokines as well as chemokine receptors. Chemokines and chemokine receptors play an important role in the occurrence and development of breast cancer. In-depth study of chemokines and chemokine receptors can provide intervention targets for breast cancer biotherapy. The regulation of chemokines and chemokine receptors may become a new strategy for breast cancer therapy.

The diverse and complex roles of atypical chemokine receptors in cancer: From molecular biology to clinical relevance and therapy

Chemokines regulate directed cell migration, proliferation and survival and are key components in cancer biology. They exert their functions by interacting with seven-transmembrane domain receptors that signal through G proteins (GPCRs). A subgroup of four chemokine receptors known as the atypical chemokine receptors (ACKRs) has emerged as essential regulators of the chemokine functions. ACKRs play diverse and complex roles in tumor biology from tumor initiation to metastasis, including cancer cell proliferation, adherence to endothelium, epithelial-mesenchymal transition (EMT), extravasation from blood vessels, tumor-associated angiogenesis or protection from immunological responses. This chapter gives an overview on the established and emerging roles that the atypical chemokine receptors ACKR1, ACKR2, ACKR3 and ACKR4 play in the different phases of cancer development and dissemination, their clinical relevance, as well as on the hurdles to overcome in ACKRs targeting as cancer therapy.

MiR-9 functions as a tumor suppressor in acute myeloid leukemia by targeting CX chemokine receptor 4

MicroRNAs (miRNAs) play key roles in the pathogenesis of many cancers, including acute myeloid leukemia (AML). Although miRNA-9 (miR-9) is involved in the leukemogenesis of AML, the underlying mechanisms remain to be elucidated. In this study, we found that miR-9 and C-X-C chemokine receptor 4 (CXCR4) were differentially expressed in myeloid leukemia, particularly in AML. The inverse correlation between miR-9 and CXCR4 was identified in AML samples and cell lines. The AML patients simultaneously with high levels of CXCR4 and low expression of miR-9 possessed poor prognosis. In vitro, miR-9 inhibited the proliferation, apoptosis resistance, migration, and invasion of AML cells. Dual luciferase assays verified CXCR4 as a direct target of miR-9. The suppressive effects of miR-9 on AML cells were counteracted or mimicked by CXCR4 overexpression or depletion, respectively. Overall, this study reveals that miR-9 retards the aggressive behaviors of AML cells by repressing CXCR4. Thus, miR-9/CXCR4 axis may represent a potential therapeutic target for AML.

miR-101 Represses T-Cell Acute Lymphoblastic Leukemia by Targeting CXCR7/STAT3 Axis

Although miR-101 is involved in the development and progression of T-cell acute lymphoblastic leukemia (T-ALL), the underlying molecular mechanisms remain unclear. In this article, we report that miR-101 expression was inversely correlated with CX chemokine receptor 7 (CXCR7) level in T-ALL. Introducing miR-101 inhibited T-ALL cell proliferation and invasion in vitro and suppressed tumor growth and lung metastasis in vivo. CXCR7 was identified as a direct target of miR-101. The inhibitory effects of miR-101 were mimicked and counteracted by CXCR7 depletion and overexpression, respectively. Mechanistically, miR-101 targets CXCR7/STAT3 axis to reduce T-ALL growth and metastasis. Overall, these findings implied the potential application of miR-101 and CXCR7 in T-ALL treatment.

MicroRNA-101 Targets CXCL12-Mediated Akt and Snail Signaling Pathways to Inhibit Cellular Proliferation and Invasion in Papillary Thyroid Carcinoma

Escalating evidence suggests that microRNA-101 (miR-101) is implicated in the development and progression of various cancers, including papillary thyroid carcinoma (PTC). However, the biological function and molecular mechanisms of miR-101 in PTC are still unclear. In this study, we demonstrated that miR-101 expression was significantly decreased in PTC tissues and cell lines. Clinically, a low level of miR-101 was positively associated with advanced histological stages and lymph node and distant metastases. The expression of CXCL12 was negatively correlated with miR-101 level in PTC. CXCL12 was validated as a direct target of miR-101 in PTC cells. Functional experiments proved that miR-101 markedly reduced the proliferation, apoptosis escape, migration, and invasion of PTC cells. Moreover, CXCL12 restoration rescued the suppressive effects of miR-101 on PTC cells by activating Akt- and EMT-associated signaling pathways. Overall, miR-101 exerts oncostatic effects on PTC by downregulating CXCL12 and repressing its downstream Akt and Snail signaling pathways, suggesting that miR-101/CXCL12/Akt or Snail axis may serve as a potential therapeutic target for PTC.

The Role of ACKR3 in Breast, Lung, and Brain Cancer

Recent reports regarding the significance of chemokine receptors in disease have put a spotlight on atypical chemokine receptor 3 (ACKR3). This atypical chemokine receptor is overexpressed in numerous cancer types and has been involved in the modulation of tumor cell proliferation and migration, tumor angiogenesis, or resistance to drugs, thus contributing to cancer progression and metastasis occurrence. Here, we focus on the clinical significance and potential mechanisms underlying the pathologic role of ACKR3 in breast, lung, and brain cancer and discuss its possible relevance as a prognostic factor and potential therapeutic target in these contexts.

The proliferation and invasion of osteosarcoma are inhibited by miR-101 via targetting ZEB2

Having a better grasp of the molecular mechanisms underlying carcinogenesis and progression in osteosarcoma would be helpful to find novel therapeutic targets. Different types of cancers have presented abnormal expression of miRNA-101 (miR-101). Nevertheless, we still could not figure out what expression of miR-101 in human osteosarcoma is and its biological function. Thus, we conducted the present study to identify its expression, function, and molecular mechanism in osteosarcoma. We detected the expression of miR-101 in osteosarcoma samples and cell lines. The effects of miR-101 on osteosarcoma cells’ proliferation and invasion were evaluated. Luciferase reporter assay was applied to identify the direct target of miR-101. Compared with adjacent normal specimens and normal bone cell line by using qPCR, the expression levels of miR-101 in osteosarcoma specimens and human osteosarcoma cell lines distinctly decreased. According to function assays, we found that overexpression of miR-101 significantly inhibited the cell proliferation and invasion in osteosarcoma cells. Moreover, we confirmed that zinc finger E-box binding homeobox 2 (ZEB2) was a direct target of miR-101. In addition, overexpression of ZEB2 could rescue the inhibition effect of proliferation and invasion induced by miR-101 in osteosarcoma cells. MiR-101 has been proved to be down-regulated in osteosarcoma and has the ability to suppress osteosarcoma cell proliferation and invasion by directly targetting ZEB2.

The Role of the CXCL12/CXCR4/ACKR3 Axis in Autoimmune Diseases

Chemokine receptors are members of the G protein-coupled receptor superfamily. These receptors are intimately involved in cell movement, and thus play a critical role in several physiological and pathological situations that require the precise regulation of cell positioning. CXCR4 is one of the most studied chemokine receptors and is involved in many functions beyond leukocyte recruitment. During embryogenesis, it plays essential roles in vascular development, hematopoiesis, cardiogenesis, and nervous system organization. It has been also implicated in tumor progression and autoimmune diseases and, together with CD4, is one of the co-receptors used by the HIV-1 virus to infect immune cells. In contrast to other chemokine receptors that are characterized by ligand promiscuity, CXCR4 has a unique ligand-stromal cell-derived factor-1 (SDF1, CXCL12). However, this ligand also binds ACKR3, an atypical chemokine receptor that modulates CXCR4 functions and is overexpressed in multiple cancer types. The CXCL12/CXCR4/ACKR3 axis constitutes a potential therapeutic target for a wide variety of inflammatory diseases, not only by interfering with cell migration but also by modulating immune responses. Thus far, only one antagonist directed against the ligand-binding site of CXCR4, AMD3100, has demonstrated clinical relevance. Here, we review the role of this ligand and its receptors in different autoimmune diseases.

Prognostic implications of decreased microRNA-101-3p expression in patients with non-small cell lung cancer

To investigate the expression level of microRNA-101-3p (miR-101-3p) and its possible association with progression, prognosis and chemotherapy in patients with non-small cell lung cancer (NSCLC), the Gene Expression Omnibus (GEO) database was used. Quantitative polymerase chain reaction was used to verify the expression in 327 NSCLC and 42 adjacent normal lung tissues, of which 42 viable tissues were paired with nearby normal lung tissues. Based on the Cox regression model, univariate and multivariate analyses were used to address the factors that had effects on overall survival (OS) and disease-free survival (DFS) rate. Data from the GEO database demonstrated that the miR-101-3p expression in NSCLC was downregulated, compared with normal lung cancer. Survival analysis through univariate and multivariate models indicated that the miR-101-3p expression level was a crucial risk factor for OS and DFS in patients with NSCLC. A number of clinical parameters were determined to be associated with miR-101-3p expression, including tumor diameter, lymph node metastasis and tumor-node-metastasis stage. Adjuvant chemotherapy with high expression of miR-101-3p was determined to increase OS and DFS in patients with NSCLC, compared with patients with de novo or low expression of miR-101-3p. The present results demonstrated that miR-101-3p expression levels were associated with NSCLC progression and prognosis, which indicated that miR-101-3p may serve as a biomarker for patients with NSCLC who have received adjuvant chemotherapy.

Diagnostic and prognostic implications of serum miR-101 in osteosarcoma

Blood-circulating microRNAs (miRNAs) have been reported to be used as potential biomarkers in various cancers. MiR-101 has been found to act as a tumor suppressor in many tumor types, but little is known for osteosarcoma. The purpose of this study was to investigate miR-101 expression in osteosarcoma patients and assess its correlation with clinical features and prognosis. Serum samples from 152 osteosarcoma patients and 70 healthy controls were detected using quantitative reverse-transcription polymerase chain reaction (qRT-PCR). The data showed that miR-101 expression levels were remarkably underexpressed in serum samples from osteosarcoma patients compared to controls, and the post-treatment serum miR-101 expression was significantly higher than that in the pre-treatment expression. Low serum miR-101 expression was positively associated with advanced clinical stage and distant metastasis. Receiver operating characteristic (ROC) curve analysis showed that serum miR-101 could serve as a useful marker for osteosarcoma diagnosis, with a high sensitivity and specificity. Moreover, patients with high miR-101 expression had longer overall survival and recurrence free survival than those with low miR-101 expression. In addition, both univariate and multivariate analyses showed that serum miR-101 downregulation was associated with shorter overall survival and recurrence free survival. Our present results implicated serum miR-101 might be a useful biomarker for the clinical diagnosis and prognosis of osteosarcoma.

Cationic graphene oxide nanoplatform mediates miR-101 delivery to promote apoptosis by regulating autophagy and stress

Introduction

MicroRNA-101 (miR-101) is an intense cancer suppressor with special algorithm to target a wide range of pathways and genes which indicates the ability to regulate apoptosis, cellular stress, metastasis, autophagy, and tumor growth. Silencing of some genes such as Stathmin1 with miR-101 can be interpreted as apoptotic accelerator and autophagy suppressor. It is hypothesized that hybrid microRNA (miRNA) delivery structures based on cationized graphene oxide (GO) could take superiority of targeting and photothermal therapy to suppress the cancer cells.

Materials and methods

In this study, GO nanoplatforms were covalently decorated with polyethylene glycol (PEG) and poly-l-arginine (P-l-Arg) that reduced the surface of GO and increased the near infrared absorption ~7.5-fold higher than nonreduced GO.

Results

The prepared nanoplatform [GO-PEG-(P-l-Arg)] showed higher miRNA payload and greater internalization and facilitated endosomal scape into the cytoplasm in comparison with GO-PEG. Furthermore, applying P-l-Arg, as a targeting agent, greatly improved the selective transfection of nanoplatform in cancer cells (MCF7, MDA-MB-231) in comparison with immortalized breast cells and fibroblast primary cells. Treating cancer cells with GO-PEG-(P-l-Arg)/miR-101 and incorporating near infrared laser irradiation induced 68% apoptosis and suppressed Stathmin1 protein.

Conclusion

The obtained results indicated that GO-PEG-(P-l-Arg) would be a suitable targeted delivery system of miR-101 transfection that could downregulate autophagy and conduct thermal stress to activate apoptotic cascades when combined with photothermal therapy.

Multifunctional core-shell nanoplatforms (gold@graphene oxide) with mediated NIR thermal therapy to promote miRNA delivery

Recent insights into the nanomedicine have revealed that nanoplatforms enhance the efficacy of carrier in therapeutic applications. Here, multifunctional nanoplatforms were utilized in miRNA-101 delivery and NIR thermal therapy to induce apoptosis in breast cancer cells. Au nanorods (NRs) or nanospheres (NSs) covered with graphene oxide (GO) were prepared and functionalized with polyethylene glycol as a stabilizer and poly-L-arginine (P-L-Arg) as a targeting agent. In nanoplatforms, coupling Au@GO prepared stable structures with higher NIR reactivity. P-L-Arg substantially enhanced the cellular uptake and gene retardation of stuffs coated by them. However, rod-shape nanoplatforms indicated better performance in cellular uptake and gene transfection than spherical ones. NIR thermal therapy was implemented to improve gene release and in synergy with miRNA-101 activated the apoptotic pathway and decreased the viability of breast cancer cell (<20%). Briefly, presented delivery systems are potentially efficient in distinguishing cancer cells, miRNA internalization and controlling apoptosis of cancer cells.

MiR-101 inhibits the proliferation and metastasis of lung cancer by targeting zinc finger E-box binding homeobox 1

MicroRNAs (miRNAs) are involved in the development and progression of lung cancer. MicroRNA-101 (miR-101) displays crucial properties in non-small cell lung cancer (NSCLC) by negatively regulating cell proliferation and invasion, but the underlying molecular mechanisms remain largely unknown. In this study, we found that miR-101 was underexpressed while zinc finger E-box binding homeobox 1 (ZEB1) was highly upregulated in NSCLC tissues and cells. The downregulation of miR-101 was positively associated with lymph node metastasis and poor prognosis of NSCLC patients. Dual-luciferase reporter assay showed that miR-101 directly targeted ZEB1 in NSCLC cells. Enforced expression of miR-101 significantly inhibited NSCLC cell proliferation, apoptosis resistance, migration, and invasion in vitro, which were attenuated by ZEB1 overexpression and phenocopied by ZEB1 knockdown, respectively. Consistently, miR-101 retarded NSCLC growth and metastasis in vivo. The findings indicated that miR-101 suppressed NSCLC growth and metastasis by targeting ZEB1, thereby providing new evidence of miR-101 as a potential therapeutic target for NSCLC patients.

Interplay between long noncoding RNA ZEB1-AS1 and miR-101/ZEB1 axis regulates proliferation and migration of colorectal cancer cells

Long noncoding RNAs (lncRNAs) are dysregulated in many diseases. MicroRNA-101 (miR-101) functions as a tumor suppressor by directly targeting ZEB1 in various cancers. However, the potential mechanism of lncRNA ZEB1-AS1 and miR-101/ZEB1 axis in CRC remains unknown. In this study, we further investigated the potential interplay between miR-101/ZEB1 axis and lncRNA ZEB1-AS1 in colorectal cancer (CRC). Results showed that ZEB1-AS1 was upregulated in CRC tissues and cells. MiR-101 was downregulated in CRC tissues and negatively correlated with ZEB1-AS1 and ZEB1 expression levels in CRC. Functional experiments showed that, consistent with ZEB1-AS1 depletion, miR-101 overexpression and ZEB1 depletion inhibited the proliferation and migration of CRC cells. Overexpression of miR-101 partially abolished the effects of ZEB1-AS1 on the proliferation and migration of these cells. Moreover, combined ZEB1-AS1 depletion and miR-101 overexpression significantly inhibited cell proliferation and migration of the CRC cells. Hence, ZEB1-AS1 functioned as a molecular sponge for miR-101 and relieved the inhibition of ZEB1 caused by miR-101. This study revealed a novel regulatory mechanism between ZEB1-AS1 and miR-101/ZEB1 axis. The interplay between ZEB1-AS1 and miR-101/ZEB1 axis contributed to the proliferation and migration of CRC cells, and targeting this interplay could be a promising strategy for CRC treatment.

The microRNA signature of patients with sunitinib failure: regulation of UHRF1 pathways by microRNA-101 in renal cell carcinoma

Molecular targeted therapy is a standard treatment for patients with advanced renal cell carcinoma (RCC). Sunitinib is one of the most common molecular-targeted drugs for metastatic RCC. Molecular mechanisms of sunitinib resistance in RCC cells is still ambiguous. The microRNA (miRNA) expression signature of patients with sunitinib failure in RCC was constructed using a polymerase chain reaction (PCR)-based array. Several miRNAs that were aberrantly expressed in RCC tissues from patients treated with sunitinib were identified in this analysis. MicroRNA-101 (miR- 101) was markedly suppressed in sunitinib treated RCC tissues. Restoration of miR-101 significantly inhibited cell migration and invasion in Caki-1 and 786-O cells. Ubiquitin-like with PHD and ring finger domains 1 (UHRF1) was directly suppressed by miR-101 in RCC cells, and overexpression of UHRF1 was confirmed in sunitinib-treated RCC tissues. The pathways of nucleotide excision repair and mismatch repair were significantly suppressed by knockdown of UHRF1. Our findings showed that antitumor miR-101- mediated UHRF1 pathways may be suppressed by sunitinib treatment.

Retracted Article: SNHG3 promotes proliferation and invasion by regulating the miR-101/ZEB1 axis in breast cancer

Background: Dysregulated lncRNA expression contributes to the pathogenesis of human tumors via the lncRNAs functioning as oncogenes or tumor suppressors. Small nucleolar RNA host gene 3 (SNHG3) was demonstrated to be upregulated in breast cancer cells. However, the detailed roles and molecular mechanism of SNHG3 in breast cancer are largely unknown. Methods: The expression of SNHG3, miR-101, and zinc finger E-box-binding protein 1 (ZEB1) in breast cancer tissues and cells was detected using qRT-PCR. The effects of SNHG3 on cell proliferation and invasion were evaluated using MTT, EdU, and cell invasion assays. The protein levels of Ki-67, proliferating cell nuclear antigen (PCNA), matrix metalloproteinase MMP-2, and MMP-9 were analyzed using western blot analysis. A luciferase reporter assay and RNA immunoprecipitation (RIP) were performed to explore the interaction between SNHG3, ZEB1 and miR-101. A subcellular fractionation assay was used to detect the subcellular location of SNHG3. Xenograft tumor experiments were conducted to verify the role and mechanism of SNHG3 in breast cancer in vivo. Results: SNHG3 expression was upregulated in breast cancer tissues and correlated with poor prognosis. SNHG3 knockdown suppressed breast cancer cell proliferation and invasion, which was further demonstrated by high levels of proliferation marker proteins Ki-67/PCNA and metastasis-related proteins MMP-2/MMP-9. Additionally, SNHG3 was located in the cytoplasm of breast cancer cells. SNHG3 functioned as a molecular sponge for miR-101 in breast cancer cells. miR-101 was downregulated in breast cancer tissues and negatively correlated with SNHG3 expression. Moreover, ZEB1, a target of miR-101, was positively regulated by SNHG3 in breast cancer cells. ZEB1 mRNA expression was upregulated in breast cancer tissues and positively correlated with SNHG3 expression. Mechanistically, SNHG3 knockdown suppressed cell proliferation and invasion by upregulation of miR-101 and downregulation of ZEB1 expression in breast cancer cells in vitro and in vivo. Conclusion: SNHG3 promoted proliferation and invasion by regulating the miR-101/ZEB1 axis in breast cancer.

In the present study, we investigated the expression and functional roles of SNHG3 in breast cancer cells, as well as the underlying mechanism of SNHG3 involved in the progression of breast cancer in vitro and in vivo.

MicroRNA-101 inhibits proliferation, migration and invasion of human glioblastoma by targeting SOX9

Glioblastoma multiforme (GBM) is the most common primary malignant tumors originating in the brain parenchyma. At present, GBM patients have a poor prognosis despite the continuous progress in therapeutic technologies including surgery, radiotherapy, photodynamic therapy, and chemotherapy. Recent studies revealed that miR-101 was remarkably down-regulated in kinds of human cancers and was associated with aggressive tumor cell proliferation and stem cell self-renewal. Data also showed that miR-101 was down-regulated in primary glioma samples and cell lines, but the underlying molecular mechanism of the deregulation of miR-101 in glioma remained largely unknown. In this study, we found that miR-101 could inhibit the proliferation and invasion of glioma cells both in vitro and in vivo by directly targeting SOX9 [sex-determining region Y (SRY)-box9 protein]. Silencing of SOX9 exerted similar effects with miR-101 overexpression on glioma cells proliferation and invasion. Quantitative reverse transcription PCR and Western blotting analysis revealed a negative relationship between miR-101 and SOX9 in human glioma U251MG and U87MG cells, and the luciferase assay indicated that miR-101 altered SOX9 expression by directly targeting on 3'UTR. Taken together, our findings suggest that miR-101 regulates glioma proliferation, migration and invasion via directly down-regulating SOX9 both in vitro and in vivo, and miR-101 may be a potential therapeutic target for future glioma treatment.

miR-139 acts as a tumor suppressor in T-cell acute lymphoblastic leukemia by targeting CX chemokine receptor 4

MicroRNAs (miRNAs) act as tumor regulators in T-cell acute lymphoblastic leukemia (T-ALL). However, the molecular mechanisms by which miRNA-139 (miR-139) regulates T-ALL remain unclear. In this study, we found that miR-139 was lowly expressed whereas C-X-C chemokine receptor type 4 (CXCR4) was highly expressed in T-ALL cell lines and patient samples. The T-ALL patients simultaneously with high levels of CXCR4 and low expression of miR-139 possessed poor prognosis. Moreover, the introduction of miR-139 inhibited T-ALL cell proliferation and invasion in vitro and suppressed tumor growth and lung metastasis in vivo. CXCR4 was identified as a direct target of miR-139. The suppressive effects of miR-139 were mimicked and counteracted by CXCR4 depletion and overexpression, respectively. Overall, the miR-139/CXCR4 axis plays an important role in T-ALL carcinogenesis.

The relationship between microRNAs and the STAT3-related signaling pathway in cancer

MicroRNAs are non-coding RNAs that regulate gene expression by targeting messenger RNA molecules in 3' untranslated region. Mounting evidence indicates that microRNAs regulate several factors to influence various biological activities that are related to carcinogenesis, including signal transducer and activator of transcription 3, which is a transcription factor that also acts as an oncogene. MicroRNAs influence signal transducer and activator of transcription 3 either by directly targeting or via other pathway components upstream or downstream of signal transducer and activator of transcription 3 such as Janus kinases, members of the suppressor of cytokine signaling family, and other genes that regulate cell proliferation, apoptosis, migration, invasion, and epithelial-mesenchymal transition. However, signal transducer and activator of transcription 3 activation changes the pattern of expression of microRNAs and mediates tumorigenesis. Moreover, the relationship between signal transducer and activator of transcription 3 and microRNAs varies among different kinds of cancers. A specific microRNA may act as an oncogene or tumor suppressor in different cancers, and microRNAs also directly or indirectly regulate signal transducer and activator of transcription 3 via pathways in the same cancers. In this review, we focus on the reciprocal regulation and roles of microRNAs and signal transducer and activator of transcription 3 in cancer, as well as describe current research progress on this relationship. A better understanding of this relationship may facilitate in the identification of targets for clinical therapeutics.

Prognostic significance of microRNA-101 in solid tumor: A meta-analysis

MicroRNA-101 has been reported as an important factor in carcinogenesis of several malignant tumors. However, its actual role in prognosis among solid malignancies remains unclear. Accordingly, we performed this meta-analysis aiming to identify prognostic significance of miR-101 in solid tumor. Pooled hazard ratios (HRs) with 95% confidence intervals (CIs) for overall survival (OS) or disease-free survival (DFS)/metastasis-free survival (MFS)/progression-free survival (PFS)/relapse-free survival (RFS)/time-to progression (TTP) were estimated with random effects or fixed effects models on the basis of heterogeneity. Subgroup analysis, sensitive analysis and meta-regression analysis were also conducted to clarify the possible confounding factors and investigate the source of heterogeneity. Publication bias was evaluated by using Begg’s and Egger’s tests. A total of 21 studies containing 3753 cases were selected into our quantitative analysis via electronic database search. A lower expression of miR-101 was significantly associated with worse OS (HR = 0.66, 95%CI [0.52–0.85], P = 0.001) and PFS (HR = 0.70, 95%CI [0.51–0.95], P = 0.023) in patients with solid tumor. The under-expression of miRNA-101 is a credible indicator of poorer prognosis in several of solid malignancies.

The prognostic value of decreased miR-101 in various cancers: a meta-analysis of 12 studies

BACKGROUND

A consensus regarding the prognostic value of decreased miR-101 in human cancers has not been reached. This study aimed to comprehensively investigate the internal associations between loss of miR-101 expression and prognostic implications in patients with cancer.

MATERIALS AND METHODS

All relevant literature in electronic databases, including PubMed, ISI Web of Science, and Embase, up to March 1, 2017 were searched. Correlations between decreased miR-101 and clinicopathological parameters were defined by odds ratios (ORs). The degree of association between reduced miR-101 and survival outcome was evaluated by pooled hazard ratios (HRs) and relevant 95% CIs.

RESULTS

Twelve eligible studies with 2,088 patients were included in this meta-analysis. Decreased miR-101 expression was closely connected with poor overall survival, with a pooled HR of 2.15 (95% CI 1.71-2.7, P<0.001). This correlation was also revealed when stratified analysis was conducted with respect to ethnicity, cancer type, sample size, specimen source, and analysis model. However, decreased miR-101 was not associated with disease-free survival, recurrence-free survival, or progression-free survival, with a pooled HR of 1.59 (95% CI 0.83-3.03, P=0.128), despite a positive trend. In addition, reduced miR-101 was intimately related to poorer tumor differentiation (OR 2.17, 95% CI 1.14-4.13; P=0.019), advanced tumor classification (OR 5.25, 95% CI 3.39-8.12; P<0.001), and higher TNM stage (OR 6.18, 95% CI 3.79-10.09; P<0.001).

CONCLUSION

Our findings suggest that loss of miR-101 expression is correlated with worse overall survival in a variety of cancers, and could serve as a predictive indicator for clinicopathological features. Furthermore, miR-101 may become a feasible therapeutic target in most human cancers.

miR-19b promotes breast cancer metastasis through targeting MYLIP and its related cell adhesion molecules

miR-19b is a key molecule for cancer development, however its crucial roles in breast cancer metastasis are rarely studied right now. In this study, using several bioinformatics databases to predict the downstream targets for miR-19b, we verified that a novel target gene, myosin regulatory light chain interacting protein (MYLIP), could be directly down-regulated by miR-19b through its 3′-UTR region. MYLIP belongs to the cytoskeletal protein clusters and is involved in the regulation of cell movement and migration. We further explored that miR-19b was highly expressed and negatively correlated with MYLIP expression in breast cancer patient samples from the TCGA database. And the over-expression of miR-19b or inhibition of MYLIP facilitated the migration and metastasis of breast cancer cells, through conducting the wound healing assay and transwell invasion assay. Additionally, miR-19b could obviously promote breast tumor growth in mouse models and affect the expressions of cell adhesion molecules (including E-Cadherin, ICAM-1 and Integrin β1) by down-regulating E-Cadherin expression and up-regulating ICAM-1 and Integrin β1 expressions in vitro and in vivo. Meanwhile, miR-19b effectively activated the Integrin β downstream signaling pathways (such as the Ras-MAPK pathway and the PI3K-AKT pathway) and elevated the expression levels of essential genes in these two pathways. Taken together, these findings comprehensively illustrate the regulatory mechanisms ofmiR-19b in breast cancer metastasis, and provide us new insights for exploring MYLIP and its related cell adhesion molecules as promising therapeutic targets to interfere breast cancer development.

CXCR7 maintains osteosarcoma invasion after CXCR4 suppression in bone marrow microenvironment

The major cause of death in osteosarcoma is the invasion and metastasis. Better understanding of the molecular mechanism of osteosarcoma invasion is essential in developing effective tumor-suppressive therapies. Interaction between chemokine receptors plays a crucial role in regulating osteosarcoma invasion. Here, we investigated the relationship between CXCR7 and CXCR4 in osteosarcoma invasion induced by bone marrow microenvironment. Human bone marrow mesenchymal stem cells were co-cultured with osteosarcoma cells to mimic actual bone marrow microenvironment. Osteosarcoma cell invasion and CXCL12/CXCR4 activation were observed within this co-culture model. Interestingly, in this co-culture model, osteosarcoma cell invasion was not inhibited by suppressing CXCR4 expression with neutralizing antibody or specific inhibitor AMD3100. Downstream signaling extracellular signal-regulated kinase and signal transducer and activator of transcription 3 were not significantly affected by CXCR4 inhibition. However, suppressing CXCR4 led to CXCR7 upregulation. Constitutive expression of CXCR7 could maintain osteosarcoma cell invasion when CXCR4 was suppressed. Simultaneously, inhibiting CXCR4 and CXCR7 compromised osteosarcoma invasion in co-culture system and suppressed extracellular signal-regulated kinase and signal transducer and activator of transcription 3 signals. Moreover, bone marrow microenvironment, not CXCL12 alone, is required for CXCR7 activation after CXCR4 suppression. Taken together, suppressing CXCR4 is not enough to impede osteosarcoma invasion in bone marrow microenvironment since CXCR7 is activated to sustain invasion. Therefore, inhibiting both CXCR4 and CXCR7 could be a promising strategy in controlling osteosarcoma invasion.

Identification of miR-101-3p targets and functional features based on bioinformatics, meta-analysis and experimental verification in hepatocellular carcinoma

BACKGROUND

MiR-101-3p has been reported to suppress invasion and metastasis in hepatocellular carcinoma (HCC) cells. However, the relevant mechanisms are still unclear. The research seeks to determine systematic value of miR-101-3p in HCC, and comprehensively summarize the predicted target genes as well as their potential function, pathways and networks in HCC.

METHODS

The miR-101-1 profiles in 353 HCC patients from The Cancer Genome Atlas (TCGA) were analyzed. Meta-analysis was performed to estimate relationship of miR-101 (including precursor and mature miR-101) with clinical features and prognosis in HCC. Further, the promising targets of miR-101-3p were predicted and followed with Gene Ontology (GO), pathway and network analysis. In addition, the functional impact of miR-101-3p was confirmed with in vitro experiments in HCC cells.

RESULTS

In TCGA data, low-expression of miR-101-1 might be a diagnostic (AUC: 0.924, 95% CI: 0.894-0.953) and prognostic (HR=1.55) marker for HCC. Down-regulated miR-101-1 also correlated with poor differentiation, advanced TNM stage, lymph node metastasis and high AFP level of HCC. Meta-analysis revealed that miR-101 down-regulation were associated with poor prognosis, high AFP level and advanced TNM stage of HCC. Moreover, 343 hub genes were filtered and miR-101-3p may be involved in intracellular signaling cascade, transcription, metabolism and cell proliferation. Focal adhesion and pathways in cancer were also significantly enriched. In vitro experiments demonstrated that miR-101-3p inhibited proliferation and promoted apoptosis in HCC cells.

CONCLUSIONS

MiR-101-1 may be a prospective biomarker for diagnosis and prognosis of HCC. Potential targets of miR-101-3p could regulate genesis and development of HCC. The data offers insights into biological significances and promising targets of miR-101-3p for further investigation and potential therapies in HCC.

Clinical Value of miR-101-3p and Biological Analysis of its Prospective Targets in Breast Cancer: A Study Based on The Cancer Genome Atlas (TCGA) and Bioinformatics

Background

MiR-101-3p can promote apoptosis and inhibit proliferation, invasion, and metastasis in breast cancer (BC) cells. However, its mechanisms in BC are not fully understood. Therefore, a comprehensive analysis of the target genes, pathways, and networks of miR-101-3p in BC is necessary.

Material/Methods

The miR-101 profiles for 781 patients with BC from The Cancer Genome Atlas (TCGA) were analyzed. Gene expression profiling of GSE31397 with miR-101-3p transfected MCF-7 cells and scramble control cells was downloaded from Gene Expression Omnibus (GEO), and the differentially expressed genes (DEGs) were identified. The potential genes targeted by miR-101-3p were also predicted. Gene Ontology (GO) and pathway and network analyses were constructed for the DEGs and predicted genes.

Results

In the TCGA data, a low level of miR-101-2 expression might represent a diagnostic (AUC: 0.63) marker, and the miR-101-1 was a prognostic (HR=1.79) marker. MiR-101-1 was linked to the estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2), and miR-101-2 was associated with the tumor (T), lymph node (N), and metastasis (M) stages of BC. Moreover, 427 genes were selected from the 921 DEGs in GEO and the 7924 potential target genes from the prediction databases. These genes were related to transcription, metabolism, biosynthesis, and proliferation. The results were also significantly enriched in the VEGF, mTOR, focal adhesion, Wnt, and chemokine signaling pathways.

Conclusions

MiR-101-1 and miR-101-2 may be prospective biomarkers for the prognosis and diagnosis of BC, respectively, and are associated with diverse clinical parameters. The target genes of miR-101-3p regulate the development and progression of BC. These results provide insight into the pathogenic mechanism and potential therapies for BC.

ERK2-ZEB1-miR-101-1 axis contributes to epithelial-mesenchymal transition and cell migration in cancer

Regulation of metastasis continues to remain enigmatic despite our improved understanding of cancer. Identification of microRNAs associated with metastasis in the recent past has provided a new hope. Here, we show how microRNA-101 (miR-101) regulates two independent processes of cellular metastasis by targeting pro-metastatic upstream regulatory transcription factors, ZEB1 and ZEB2, and downstream effector-actin modulators, RHOA and RAC1, providing a single target for therapeutic intervention. Further, we depict how down-regulation of miR-101 by extracellular signal-regulated kinase-2 (ERK2) is vital for MAP kinase pathway induced cellular migration and mesenchymal transition. Importantly, EKR2 induced expression of ZEB1 seems essential for down-regulation of miR-101-1 and induction of EMT. Given the role of EMT in metastasis, we also observe a significant correlation between miR-101 expression and lymph node metastasis; and identify the ERK2-ZEB1-miR-101-1 pathway active in breast cancer tissues, with an apparent clinicopathological implication.

Cancer and the metastatic substrate

Seventy percent of cancer patients have detectable metastases when they receive a diagnosis and 90% of cancer deaths result from metastases. These two facts emphasise the urgency for research to study the mechanisms and processes that enable metastasis. We need to develop a greater understanding of the cellular and molecular mechanisms that cause metastasis and also we need to do more. We must also consider the micro- and macro-environmental factors that influence this disease. Studying this environmental context has led us to update the ‘seed and soil’ hypothesis which dates back to the 19th century. This theory describes cancerous cells as seeds and the substrate as the soil in target organs though this may seem antiquated. Nonetheless, the tissue specificity that researchers have recently observed in metastatic colonisation supports the validity of the seed and soil theory. We now know that the metastatic potential of a tumour cell depends on multiple, reciprocal interactions between the primary tumour and distant sites. These interactions determine tumour progression. Studies of metastasis have allowed us to develop treatments that focus on therapeutic effectiveness. These new treatments account for the frequent metastasis of some tumours to target organs such as bones, lungs, brain, and liver. The purpose of this review is first to describe interactions between the cellular and molecular entities and the target organ tumour environment that enables metastasis. A second aim is to describe the complex mechanisms that mediate these interactions.

miRNA-101 acts as a tumor suppressor in oral squamous cell carcinoma by targeting CX chemokine receptor 7

miR-101 is significantly downregulated in various human cancers, including oral squamous cell carcinoma (OSCC). However, the role of miR-101 in OSCC has not been elucidated. In this study, miR-101 lowly expressed in OSCC tissues and cell lines compared with that in adjacent normal tissues and human normal oral keratinocyte cells. Bioinformatics analysis predicted that miR-101 could potentially target CX chemokine receptor 7 (CXCR7), a promoter of tumor development, to attenuate OSCC progression. Restoring miR-101 expression in OSCC cells suppressed cell proliferation, invasion, and migration. The ectopic expression of CXCR7 in OSCC cells overexpressing miR-101 restored the proliferation and motility capabilities abolished by miR-101. The inhibitory effects of miR-101 on OSCC growth and metastasis were mimicked by CXCR7 knockdown in vivo. CXCR7 expression was upregulated in OSCC tissues. The high expression level of CXCR7 was negatively correlated with miR-101 level and poor prognosis of patients with OSCC. Overall, miR-101 exerts tumor-suppressive functions by targeting CXCR7, leading to inhibition of OSCC cell growth, invasion, and migration. Hence, miR-101 may be a potential target for OSCC diagnosis and therapeutic applications.

MiR-101 targets USP22 to inhibit the tumorigenesis of papillary thyroid carcinoma

Increasing evidence suggests that microRNA-101 (miR-101) is involved in the progression of various human cancers, including papillary thyroid carcinoma (PTC). However, the biological functions of miR-101 and underlying molecular mechanisms in PTC remain largely unknown. In this study, we demonstrated that miR-101 underexpression in PTC tissue was associated with lymph node metastasis and poor prognosis of PTC patients. MiR-101 reduced PTC cell proliferation, apoptosis resistance, and invasion. Ubiquitin-specific protease 22 (USP22) was confirmed as a direct target of miR-101. USP22 restoration attenuated the inhibitory effects of miR-101 on PTC malignant traits in vitro. In vivo, miR-101 overexpression or USP22 depletion reduced the tumorigenesis of PTC. Overall, our findings provide new insight into the mechanism of PTC inhibition by miR-101, suggesting the potential of miR-101 as a therapeutic target in PTC patients.

Involvement of microRNAs in HER2 signaling and trastuzumab treatment

The prognostic value of HER2 has been demonstrated in many human cancer types such us breast cancer, gastric cancer and ovarian cancer. Trastuzumab is the first anti-HER2 monoclonal antibody that has remarkably improved outcomes of patients with HER2-positive breast cancer. For HER2-positive metastatic gastric cancers, the addition of trastuzumab to traditional chemotherapy also significantly prolonged overall survival. However, intrinsic and acquired resistance to trastuzumab is common and results in disease progression. HER2 signaling network and mechanisms underlying the resistance have been broadly investigated in order to develop strategy to overcome the dilemma. Increasing evidence indicates that microRNAs (miRNA), a group of small non-coding RNAs, are involved in HER2 signaling and trastuzumab treatment. This review summarizes all the miRNAs that target HER2 and describes their activity on biological processes. Moreover, miRNAs that regulate trastuzumab resistance and relevant molecular mechanisms are highlighted. MiRNA signatures associated with HER2, miRNAs that mediate trastuzumab activity, and potential miRNA biomarkers of trastuzumab sensitivity are also discussed.

MicroRNA-101 regulates T-cell acute lymphoblastic leukemia progression and chemotherapeutic sensitivity by targeting Notch1

The present study aimed to investigate the role of microRNA (miR)-101 in acute lymphoblastic leukemia progression and chemoresistance. Furthermore, a novel target gene of miR-101 was identified. Here, we confirmed that miR-101 was significantly downregulated in the blood samples of patients with T-cell acute lymphoblastic leukemia (T-ALL) compared with the healthy controls, as determined by reverse transcription quantitative polymerase chain reaction (RTqPCR) analysis. The in vitro experiments demonstrated that miR-101 significantly repressed the proliferation and invasion, and induced potent apoptosis in Jurkat cells, as determined by CCK-8, flow cytometer and cell invasion assays. Luciferase assay confirmed that Notch1 was a target gene of miR-101, and western blotting showed that miR-101 suppressed the expression of Notch1 at the protein level. Moreover, functional restoration assays revealed that Notch1 mediates the effects of miR-101 on Jurkat cell proliferation, apoptosis and invasion. miR-101 enhanced the sensitivity of Jurkat cells to the chemotherapeutic agent adriamycin. Taken together, our results show for the first time that miR-101 acts as a tumor suppressor in T-cell acute lymphoblastic leukaemia and it could enhance chemotherapeutic sensitivity. Furthermore, Notch1 was identified to be a novel target of miR-101. This study indicates that miR-101 may represent a potential therapeutic target for T-cell acute lymphoblastic leukemia intervention.

MiRNA-101 inhibits oral squamous-cell carcinoma growth and metastasis by targeting zinc finger E-box binding homeobox 1

MicroRNAs (miRNAs) are implicated in the pathogenesis of oral squamous-cell carcinoma (OSCC). miR-101 is involved in the development and progression of OSCC, but the biological functions and underlying molecular mechanisms of this miRNA remain largely unknown. In this study, we showed that miR-101 was underexpressed in OSCC tissues and cell lines. miR-101 downregulation was inversely correlated with zinc finger E-box binding homeobox 1 (ZEB1) expression, lymph-node metastasis, and poor prognosis in OSCC patients. Enhanced expression of miR-101 significantly inhibited OSCC cell proliferation, apoptosis resistance, migration and invasion in vitro, and suppressed tumor growth and lung metastasis in vivo. Bioinformatics analyses showed that miR-101 directly targeted ZEB1, as confirmed by a dual-luciferase reporter assay. The inhibitory effects of miR-101 on OSCC growth and metastasis were attenuated and phenocopied by ZEB1 overexpression and knockdown, respectively. Overall, our findings indicated that miRNA-101 reduced OSCC growth and metastasis by targeting ZEB1 and provided new evidence of miR-101 as a potential therapeutic target for OSCC patients.

miR-27a-3p suppresses tumor metastasis and VM by down-regulating VE-cadherin expression and inhibiting EMT: an essential role for Twist-1 in HCC

Twist-1 and miRNAs have been reported to be associated with tumor metastasis and angiogenesis. However, the relationship between Twist-1 and miRNAs and the function of miRNAs remain largely undefined. We aimed to reveal the Twist-1-related miRNA expression profile and to determine whether Twist-1 functions in tumor metastasis and vasculogenic mimicry (VM) by regulating miRNA expression in hepatocellular carcinoma (HCC). Results showed that the expression of miR-27a-3p was consistently down-regulated in HCC cell lines and tissue samples displaying high expression of Twist-1. Both loss- and gain-of-function assays revealed suppressive effects of miR-27a-3p. Low miR-27a-3p expression was significantly associated with early metastasis in HCC. Subsequent investigations revealed that miR-27a-3p mediated the inhibition of epithelial–mesenchymal transition (EMT). Additional experiments showed that VE-cadherin is a direct target of miR-27a-3p and further demonstrated the critical role of miR-27a-3p in suppressing tumor metastasis and VM. Conclusions: Twist-1 up-regulation in HepG2 cells resulted in the differential expression of 18 miRNAs. Among them, miR-27a-3p deregulation contributed to VM and metastasis. The miR-27a-3p-mediated down-regulation of VE-cadherin and inhibition of EMT may be essential for Twist-1 to induce tumor metastasis and VM. Our findings highlight the importance of miR-27a-3p and suggest a promising new strategy for anti-HCC therapy.