MiR-507 inhibits the migration and invasion of human breastcancer cells through Flt-1 suppression

Circ_0007386 Promotes the Progression of Hepatocellular Carcinoma Through the miR-507/ CCNT2 Axis

Background

Circular RNAs (circRNAs) have been shown to play a crucial role in the initiation and development of Hepatocellular carcinoma (HCC). However, the mechanism and function of circ_0007386 in HCC are still unknown.

Methods

Circ_0007386 expression level in HCC tissues, and HCC cell lines was further analyzed by qRT-PCR. Agarose gel electrophoresis and Sanger sequencing were used to figure out the structure of circ_0007386. The involvement of circ_0007386 in HCC development was evaluated by experimental investigations conducted in both laboratory settings (in vitro) and living organisms (in vivo). RNA immunoprecipitation, Western blotting, luciferase reporter assay and fluorescence in situ hybridization (FISH) were applied for finding out the interaction among circ_0007386, miR-507 and CCNT2. To assess the connection between circ_0007386 and lenvatinib resistance, lenvatinib-resistant HCC cell lines were employed.

Results

The expression of circ_0007386 was found to increase in HCC tissues, and it was observed to be associated with a worse prognosis. Overexpression of circ_0007386 stimulated HCC cells proliferation, invasion, migration and the epithelial-mesenchymal transition (EMT) while silencing of circ_0007386 resulted in the opposite effect. Mechanistic investigations revealed that circ_0007386 acted as a competing endogenous RNA of miR-507 to prevent CCNT2 downregulation. Downregulating miR-507 or overexpressing CCNT2 could reverse phenotypic alterations that originated from inhibiting of circ_0007386. Importantly, circ_0007386 determines the resistance of hepatoma cells to lenvatinib treatment.

Conclusion

Circ_0007386 advanced HCC progression and lenvatinib resistance through the miR-507/ CCNT2 axis. Meanwhile, circ_0007386 served as a potential biomarker and therapeutic target in HCC patients.

Knockdown of circADAM9 inhibits cell progression and glycolysis by targeting the miR-1236-3p/FGF7 axis in breast cancer

BACKGROUND

Circular RNAs (circRNAs) are closely associated with the development of breast cancer (BC). In this study, we aimed to clarify how differentially expressed circRNAs affect the development of BC.

METHODS

Quantitative real-time polymerase chain reaction (qRT-PCR) was used to detect the expression of circADAM9, miR-1236-3p and fibroblast growth factor 7 (FGF7). Colony formation, 5-ethynyl-2'-deoxyuridine (EdU), wound healing, transwell, and flow cytometry were used to assess cell proliferation, migration, invasion, and apoptosis. Glucose consumption, lactic acid production and ATP levels were assessed using glycolysis metabolism analysis. Dual-luciferase reporter assay and RNA immunoprecipitation (RIP) assay were carried out to verify the relationship between miR-1236-3p and circADAM9 or FGF7. The roles of cirADAM9 on tumor growth were analyzed using a xenograft tumor model. Ki-67 and FGF7 expression was measured via immunohistochemistry (IHC) assay. Apoptosis-related proteins and exosome markers were detected by western blot.

RESULTS

CircADAM9 was highly expressed in BC cells, and circADAM9 silencing inhibited BC cell proliferation, migration, invasion, and glycolysis, and promoted cell apoptosis. Furthermore, miR-1236-3p inhibition could overturn circADAM9 knockdown-mediated BC inhibition. Moreover, the negative influences of miR-1236-3p overexpression on BC progression were restrained via FGF7 overexpression. CircADAM9 silence also inhibited BC tumor growth in vivo.

CONCLUSION

CircADAM9 promoted BC development partly by the miR-1236-3p/FGF7 axis, highlighting a potential prognostic biomarker and therapeutic target for BC patients.

Crosstalk between long noncoding RNA and microRNA in Cancer

miRNAs and lncRNAs play a central role in cancer-associated gene regulations. The dysregulated expression of lncRNAs has been reported as a hallmark of cancer progression, acting as an independent prediction marker for an individual cancer patient. The interplay of miRNA and lncRNA decides the variation of tumorigenesis that could be mediated by acting as sponges for endogenous RNAs, regulating miRNA decay, mediating intra-chromosomal interactions, and modulating epigenetic components. This paper focuses on the influence of crosstalk between lncRNA and miRNA on cancer hallmarks such as epithelial-mesenchymal transition, hijacking cell death, metastasis, and invasion. Other cellular roles of crosstalks, such as neovascularization, vascular mimicry, and angiogenesis were also discussed. Additionally, we reviewed crosstalk mechanism with specific host immune responses and targeting interplay (between lncRNA and miRNA) in cancer diagnosis and management.

Comprehensive analysis identifies as a critical prognostic prediction gene in breast cancer

BACKGROUND

Aurora kinases (AURKs) family plays a vital role not only in cell division but also in tumorigenesis. However, there are still rare systematic analyses of the diverse expression patterns and prognostic value of the AURKs family in breast cancer (BC). Systematic bioinformatics analysis was conducted to explore the biological role, prognostic value, and immunologic function of AURKs family in BC.

METHODS

The expression, prognostic value, and clinical functions of AURKs family in BC were evaluated with several bioinformatics web portals: ONCOMINE Gene Expression Profiling Interactive Analysis, Kaplan-Meier plotter, cBioPortal, Metascape, GeneMANIA, and LinkedOmics; and the result was verified using human tissues.

RESULTS

The expression of AURKA and AURKB were upregulated in BC in subgroup analyses based on tumor stage (all P   <  0.05). BC patients with high AURKA and AURKB expression had a worse overall survival, relapse-free survival, and distant metastasis-free survival (all P   <  0.05). Verification experiment revealed that AURKA and AURKB were upregulated in BC ( P  < 0.05). AURKA and AURKB were specifically associated with several tumor-associated kinases (polo-like kinase 1 and cyclin-dependent kinase 1), miRNAs (miR-507 and miR-381), and E2F transcription factor 1. Moreover, AURKA and AURKB were correlated with immune cell infiltration. Functional enrichment analysis revealed that AURKA and AURKB were involved in the cell cycle signaling pathway, platinum drug resistance signaling pathway, ErbB signaling pathway, Hippo signaling pathway, and nucleotide-binding and oligomerization domain-like receptor signaling pathway.

CONCLUSIONS

Aurora kinases AURKA and AURKB could be employed as novel prognostic biomarkers or promising therapeutic targets for BC.

Circ_0089823 reinforces malignant behaviors of non-small cell lung cancer by acting as a sponge for microRNAs targeting SOX4. Neoplasia 2021;23:887-897. [PMID: 34311177 PMCID: PMC8326602 DOI: 10.1016/j.neo.2021.06.011]

In recent years, increasing evidence indicates the significant roles of circRNAs in carcinogenesis. However, their roles in lung cancer remain largely unclear. We profiled the circRNA expression in 10 paired non-small cell lung cancer (NSCLC) and adjacent non-cancer tissues using high-throughput sequencing. A total of 183 up-regulated and 428 down-regulated circRNAs were identified in the NSCLC tissues (fold change ≥ 2, P < 0.05). Circ_0089823, an up-regulated circRNA (5.4-fold, P = 0.0017), was further investigated through loss-of-function and gain-of-function. The circ_0089823 level in NSCLC samples was related to the gender, tumor size, pathological type, TNM stage and smoking history. Knockdown of circ_0089823 suppressed cell proliferation, induced cell cycle arrest and apoptosis of NSCLC cells in vitro. Additionally, circ_0089823-silenced xenografts grew much slowly. On the contrary, its over-expression promoted the malignant behaviors of NSCLC cells. Furthermore, SOX4, a tumor-promoting transcription factor, was highly expressed in NSCLC tissues and positively regulated by circ_0089823. Bioinformatic analysis revealed several potential binding sites for miR-507, miR-557, miR-579-3p and miR-1287-5p in circ_0089823 and SOX4 3'-untranslated region, which was later confirmed by luciferase reporter assay. Interestingly, silencing SOX4 countervailed the effects of circ_0089823 over-expression on NSCLC cells. Here, we revealed that circ_0089823 might act as a sponge of microRNAs targeting SOX4, thus increasing the expression of SOX4, thereby reinforcing the malignant behaviors of NSCLC cells. This study indicates that circ_0089823 has the potential to become a candidate target for NSCLC treatment.

In vivo and in vitro impact of miRNA-153 on the suppression of cell growth apoptosis through mTORC2 signaling pathway in breast cancer

PURPOSE

To investigate the effects and mechanism of miRNA-153 on breast cancer cells in vitro and in vivo.

MATERIAL AND METHODS

The cells and mice were divided into five groups: miRNA-153 mimic, miRNA-153 NC, miRNA-153 inhibitor, miRNA-153 inhibitor-NC, and blank control groups. The real-time PCR and western blot were used to detect the rictor expression regulated by miRNA-153. The western blot was used to explore the expression levels of p-Akt Ser473, p-SGK1 Ser422, and p-FOXO1 Thr24 regulated by miRNA-153. The H&E stain was used to detect the morphology and vitality of tumor cells. Flow cytometry analysis or TUNEL detection was used to evaluate the apoptosis of tumor cells.

RESULTS

MiRNA-153 was significantly reduced in breast cancer cell lines. The real-time PCR and western blot assay suggested that the miRNA-153 downregulation of rictor expression, which was correlated with the antitumor effects both in vitro and in vivo. The western blot assay also showed that the expression levels of p-Akt Ser473, p-SGK1 Ser422, and p-FOXO1 Thr24 were largely reduced in miRNA-153 treated group, which indicated that miRNA-153 inhibited breast cancer growth by regulation of mTORC2 signaling pathway. The H&E stain demonstrated that the morphology and vitality of tumor cells in tumor tissues were influenced in miRNA-153 mimic treated group. The TUNEL detection also showed a great quantity of apoptotic cells in the miRNA-153 mimic group.

CONCLUSIONS

All these results uncovering that the miRNA-153 inhibited breast cancer growth via regulation of mTORC2 signaling pathway, which provided breast cancer treatment a novel direction.

Silencing hsa_circ_0007841 Inhibits Cell Proliferation and Promotes Cell Apoptosis via Regulating miR-507 in Multiple Myeloma Cells

Recently study has indicated that hsa_circ_0007841 is up-regulated in patients with multiple myeloma and may act as an important biomarker in Multiple myeloma. However, the mechanisms and effects of hsa_circ_0007841 remain unclear and were firstly investigated herein. The gene expression level was detected via PCR assay. The CCK-8 assay was performed to measure the cell viability. The cell proliferation capacity was evaluated via colony formation assay. The protein express level was detected by western blot and cell apoptosis via flow cytometry. The target of hsa_circ_0007841 was predicted via CircInteractome online tool and validated by luciferase reporter assay. Hsa_circ_0007841 was overexpressed and miR-507 was poorly expressed in multiple myeloma cells. Silencing hsa_circ_0007841 has anti-proliferation and pro-apoptosis effects in multiple myeloma cells. MiR-507 was found to be the target of hsa_circ_0007841. Inhibition of miR-507 relieved the effects of silencing hsa_circ_0007841 in myeloma cells. Silencing hsa_circ_0007841 suppressed cellular proliferative ability and enhanced cell apoptosis rate via targeting and up-regulating miRNA-507 in multiple myeloma cells.

ChrXq27.3 miRNA cluster functions in cancer development

MicroRNAs (miRNAs) regulate the expression of their target genes post-transcriptionally; thus, they are deeply involved in fundamental biological processes. miRNA clusters contain two or more miRNA-encoding genes, and these miRNAs are usually coexpressed due to common expression mechanisms. Therefore, miRNA clusters are effective modulators of biological pathways by the members coordinately regulating their multiple target genes, and an miRNA cluster located on the X chromosome q27.3 region has received much attention in cancer research recently. In this review, we discuss the novel findings of the chrXq27.3 miRNA cluster in various types of cancer.

The chrXq27.3 miRNA cluster contains 30 mature miRNAs synthesized from 22 miRNA-encoding genes in an ~ 1.3-Mb region. The expressions of these miRNAs are usually negligible in many normal tissues, with the male reproductive system being an exception. In cancer tissues, each miRNA is dysregulated, compared with in adjacent normal tissues. The miRNA-encoding genes are not uniformly distributed in the region, and they are further divided into two groups (the miR-506-514 and miR-888-892 groups) according to their location on the genome. Most of the miRNAs in the former group are tumor-suppressive miRNAs that are further downregulated in various cancers compared with normal tissues. miR-506-3p in particular is the most well-known miRNA in this cluster, and it has various tumor-suppressive functions associated with the epithelial–mesenchymal transition, proliferation, and drug resistance. Moreover, other miRNAs, such as miR-508-3p and miR-509-3p, have similar tumor-suppressive effects. Hence, the expression of these miRNAs is clinically favorable as prognostic factors in various cancers. However, the functions of the latter group are less understood. In the latter group, miR-888-5p displays oncogenic functions, whereas miR-892b is tumor suppressive. Therefore, the functions of the miR-888–892 group are considered to be cell type- or tissue-specific.

In conclusion, the chrXq27.3 miRNA cluster is a critical regulator of cancer progression, and the miRNAs themselves, their regulatory mechanisms, and their target genes might be promising therapeutic targets.

A novel lncRNA-miRNA-mRNA competitive endogenous RNA network for uveal melanoma prognosis constructed by weighted gene co-expression network analysis

AIMS

Uveal melanoma (UM) is the most common and aggressive intraocular tumor in adults, and long-term survival of UM patients remains poor. Abnormal competitive endogenous RNA (ceRNA) networks promote the initiation and progression of many tumors and may thus serve as useful prognostic indicators. Here, we do a comprehensive analysis of long non-coding RNA (lncRNA)-microRNA (miRNA)-mRNA ceRNA networks as prognostic markers for UM.

MATERIALS AND METHODS

The Cancer Genome Atlas UM dataset was used to identify survival-related mRNA and lncRNA modules through weighted gene co-expression network analysis (WGCNA). Prognostic miRNAs were identified using univariate Cox proportional hazard regression. We then used Cox and least absolute shrinkage and selection operator regression to screen for prognostic hub mRNAs and establish a hub ceRNA network. A nomogram of five hub mRNAs was constructed and Kaplan-Meier survival analysis performed.

KEY FINDINGS

Six mRNA modules were constructed, two of which involved 1490 mRNAs that significantly correlated with survival. Among the three lncRNA modules constructed, one involved 199 survival-related lncRNAs. Five hub prognostic mRNAs were identified and a hub ceRNA network constructed, consisting of six lncRNAs, four miRNAs, and five mRNAs, with high prognostic value.

SIGNIFICANCE

We describe a hub ceRNA network of survival-associated lncRNAs, miRNAs, and mRNA that may underlie a critical post-translational regulatory mechanism determining UM aggression. These hub RNAs may be valuable prognostic markers and therapeutic targets in UM.

A Novel Circular RNA, circ_0005394, Predicts Unfavorable Prognosis and Contributes to Hepatocellular Carcinoma Progression by Regulating miR-507/E2F3 and miR-515-5p/CXCL6 Signaling Pathways

Objective

Circular RNAs (circRNAs) play a key role in cancer development and progression. Previously, circ_0005394 was found to be highly expressed in hepatocellular carcinoma (HCC) screened by circRNA microarray. However, the research with regard to the functions and mechanisms of circ_0005394 in HCC remains unknown.

Materials and Methods

The expression of circ_0005394 in HCC was measured by qRT-PCR. The clinical relevance was evaluated by Fisher's exact test, Kaplan-Meier curves, and Cox regression model. Gain/loss-of function assays were performed to elucidate the functions of circ_0005394 in Huh-7 and HepG2 cells. Dual-luciferase reporter assay was applied to reveal the mechanism of circ_0005394.

Results

circ_0005394 expression was higher in HCC tissues and cells than noncancerous samples and normal cell line, respectively. High expression of circ_0005394 was associated with larger tumor size, more advanced TNM stages, and poorer overall survival for the patients with HCC. Gain/loss-of function assays demonstrated its oncogenic role in cell growth, apoptosis, migration, and invasion. Mechanistically, miR-507 and miR-515-5p could be sponged by circ_0005394. Furthermore, E2F Transcription Factor 3 (E2F3) and C-X-C motif chemokine ligand 6 (CXCL6) were confirmed as the target of miR-507 and miR-515-5p, respectively. Rescue assay indicated that circ_0005394 facilitated HCC growth and invasion by regulating miR-507/E2F3 and miR-515-5p/CXCL6 signaling pathways.

Conclusion

This study uncovered an important role of circ_0005394 in regulating HCC progression, providing a novel perspective for clarifying its pathogenesis.

MicroRNAs in cancer therapy: Their involvement in oxaliplatin sensitivity/resistance of cancer cells with a focus on colorectal cancer

The resistance of cancer cells into chemotherapy has restricted the efficiency of anti-tumor drugs. Oxaliplatin (OX) being an anti-tumor agent/drug is extensively used in the treatment of various cancer diseases. However, its frequent application has led to chemoresistance. As a consequence, studies have focused in finding underlying molecular pathways involved in OX resistance. MicroRNAs (miRs) are short endogenous non-coding RNAs that are able to regulate vital biological mechanisms such as cell proliferation and cell growth. The abnormal expression of miRs occurs in pathological events, particularly cancer. In the present review, we describe the involvement of miRs in OX resistance and sensitivity. The miRs are able to induce the oncogene factors and mechanisms, resulting in stimulation OX chemoresistance. Also, onco-suppressor miRs can enhance the sensitivity of cancer cells into OX chemotherapy and trigger apoptosis and cell cycle arrest, leading to reduced viability and progression of cancer cells. MiRs can also enhance the efficacy of OX chemotherapy. It is worth mentioning that miRs affect various down-stream targets in OX resistance/sensitivity such as STAT3, TGF-β, ATG4B, FOXO1, LATS2, NF-κB and so on. By identification of these miRs and their upstream and down-stream mediators, further studies can focus on targeting them to sensitize cancer cells into OX chemotherapy and induce apoptotic cell death.

Uncovering Prognosis-Related Genes and Pathways by Multi-Omics Analysis in Lung Cancer

Lung cancer is one of the leading causes of death worldwide. Therefore, understanding the factors linked to patient survival is essential. Recently, multi-omics analysis has emerged, allowing for patient groups to be classified according to prognosis and at a more individual level, to support the use of precision medicine. Here, we combined RNA expression and miRNA expression with clinical information, to conduct a multi-omics analysis, using publicly available datasets (the cancer genome atlas (TCGA) focusing on lung adenocarcinoma (LUAD)). We were able to successfully subclass patients according to survival. The classifiers we developed, using inferred labels obtained from patient subtypes showed that a support vector machine (SVM), gave the best classification results, with an accuracy of 0.82 with the test dataset. Using these subtypes, we ranked genes based on RNA expression levels. The top 25 genes were investigated, to elucidate the mechanisms that underlie patient prognosis. Bioinformatics analyses showed that the expression levels of six out of 25 genes (ERO1B, DPY19L1, NCAM1, RET, MARCH1, and SLC7A8) were associated with LUAD patient survival (p < 0.05), and pathway analyses indicated that major cancer signaling was altered in the subtypes.

MicroRNA-150-5p promotes cell motility by inhibiting c-Myb-mediated Slug suppression and is a prognostic biomarker for recurrent ovarian cancer

Treatment of ovarian cancer (OvCa) remains challenging owing to its high recurrence rates. Detachment of cancer cells into the peritoneal fluid plays a key role in OvCa relapse, but how this occurs remains incompletely understood. Here we examined global miRNA expression profiles of paired primary/recurrent OvCa specimens and identified a novel biomarker, microRNA-150-5p (miR-150-5p), that was significantly upregulated in 16 recurrent OvCa tissues compared with their matched primary specimens. Analyses of cohorts from two other groups confirmed that expression of miR-150-5p was associated with early relapse and poor survival of OvCa patients. Inhibition of miR-150-5p significantly inhibited the migration and invasion of OvCa cells and induced a mesenchymal-epithelial transition (MET) phenotype. We demonstrated that the proto-oncogene, MYB, is an miR-150-5p target in OvCa cells and that the miR-150-5p/c-Myb/Slug axis plays important roles in regulating epithelial-mesenchymal transition (EMT) in OvCa cells. Expression of MYB was significantly correlated with good clinical outcome in OvCa and was negatively correlated with Slug expression in late-stage clinical specimens. These results suggest that miR-150-5p upregulation mediates the progression of recurrent OvCa by targeting the c-Myb/Slug pathway. Inhibition of miR-150-5p may serve as a new therapeutic strategy for preventing recurrence of OvCa.

Long Non-Coding RNA LINC00525 Promotes the Stemness and Chemoresistance of Colorectal Cancer by Targeting miR-507/ELK3 Axis

Background and Objectives

This study aims to explore the effects of a long non-coding RNA, LINC00525, on colorectal cancer (CRC) and its underlying molecular mechanisms.

Methods

The qPCR, MTT, colony formation, Western blotting, Luciferase reporter and biotin pull-down, shRNA knockdown and DNA fragmentation assays were performed in this study.

Results

High expressions of LINC00525 were associated with poor prognosis of CRC patients. LINC00525 knockdown decreased stemness properties and increased sensitivities to oxaliplatin. MiR-507 was a direct target of LINC00525 and overexpression of miR-507 significantly decreased abilities of tumorsphere formation and cell growth. Overexpression of miR-507 resulted in a decrease of expression of cancer stem cell markers and the increase of apoptosis rates. MiR-507 regulated the expression of ELK3. In addition, LINC00525 knockdown decreased the expression of ELK3. Restoration of ELK3 expression abrogated the effects of LINC00525 knockdown. LINC00525 could be served as prognostic marker of CRC.

Conclusions

LINC00525 enhanced stemness properties and increased sensitivities of CRC cells to oxaliplatin by targeting miR-507/ELK3 axis.

Crosstalk between the lncRNA UCA1 and microRNAs in cancer

Long non-coding RNAs (lncRNAs) are a major subset of highly conserved non-coding RNAs (ncRNAs) that consist of at least 200 nucleotides and have limited protein-coding potential. Cumulative data have shown that lncRNAs are deregulated in many types of cancer and may control pathophysiological processes of cancer at various levels, including transcription, post-transcription and translation. Recently, lncRNAs have been demonstrated to interact with microRNAs (miRNAs), another major subset of ncRNAs, which regulate physiological and pathological processes by inhibiting target mRNA translation or promoting mRNA degradation. The lncRNA urothelial carcinoma-associated 1 (UCA1) has recently gained much attention as it is overexpressed in many types of cancer and is involved in carcinogenesis. Here, we review the crosstalk between UCA1 and miRNAs during the pathogenesis of cancer, with a focus on cancer-cell proliferation, invasion, drug resistance, and metabolism.

HNRNPA2/B1 is upregulated in endocrine-resistant LCC9 breast cancer cells and alters the miRNA transcriptome when overexpressed in MCF-7 cells

MicroRNAs are dysregulated in breast cancer. Heterogeneous Nuclear Ribonucleoprotein A2/B1 (HNRNPA2/B1) is a reader of the N(6)-methyladenosine (m6A) mark in primary-miRNAs (pri-miRNAs) and promotes DROSHA processing to precursor-miRNAs (pre-miRNAs). We examined the expression of writers, readers, and erasers of m6A and report that HNRNPA2/B1 expression is higher in tamoxifen-resistant LCC9 breast cancer cells as compared to parental, tamoxifen-sensitive MCF-7 cells. To examine how increased expression of HNRNPA2/B1 affects miRNA expression, HNRNPA2/B1 was transiently overexpressed (~5.4-fold) in MCF-7 cells for whole genome miRNA profiling (miRNA-seq). 148 and 88 miRNAs were up- and down-regulated, respectively, 48 h after transfection and 177 and 172 up- and down-regulated, respectively, 72 h after transfection. MetaCore Enrichment analysis identified progesterone receptor action and transforming growth factor β (TGFβ) signaling via miRNA in breast cancer as pathways downstream of the upregulated miRNAs and TGFβ signaling via SMADs and Notch signaling as pathways of the downregulated miRNAs. GO biological processes for mRNA targets of HNRNPA2/B1-regulated miRNAs included response to estradiol and cell-substrate adhesion. qPCR confirmed HNRNPA2B1 downregulation of miR-29a-3p, miR-29b-3p, and miR-222 and upregulation of miR-1266-5p, miR-1268a, miR-671-3p. Transient overexpression of HNRNPA2/B1 reduced MCF-7 sensitivity to 4-hydroxytamoxifen and fulvestrant, suggesting a role for HNRNPA2/B1 in endocrine-resistance.

Multifaceted Role of the Placental Growth Factor (PlGF) in the Antitumor Immune Response and Cancer Progression

The sharing of molecules function that affects both tumor growth and neoangiogenesis with cells of the immune system creates a mutual interplay that impairs the host’s immune response against tumor progression. Increasing evidence shows that tumors are able to create an immunosuppressive microenvironment by recruiting specific immune cells. Moreover, molecules produced by tumor and inflammatory cells in the tumor microenvironment create an immunosuppressive milieu able to inhibit the development of an efficient immune response against cancer cells and thus fostering tumor growth and progression. In addition, the immunoediting could select cancer cells that are less immunogenic or more resistant to lysis. In this review, we summarize recent findings regarding the immunomodulatory effects and cancer progression of the angiogenic growth factor namely placental growth factor (PlGF) and address the biological complex effects of this cytokine. Different pathways of the innate and adaptive immune response in which, directly or indirectly, PlGF is involved in promoting tumor immune escape and metastasis will be described. PlGF is important for building up vascular structures and functions. Although PlGF effects on vascular and tumor growth have been widely summarized, its functions in modulating the immune intra-tumoral microenvironment have been less highlighted. In agreement with PlGF functions, different antitumor strategies can be envisioned.

Long non-coding RNA ZEB2-AS1 promotes the proliferation, metastasis and epithelial mesenchymal transition in triple-negative breast cancer by epigenetically activating ZEB2

The triple‐negative breast cancer is the most malignant type of breast cancer. Its pathogenesis and prognosis remain poor despite the significant advances in breast cancer diagnosis and therapy. Meanwhile, long noncoding RNAs (LncRNAs) play a pivotal role in the progression of malignant tumors. In this study, we found that LncRNA‐ZEB2‐AS1 was dramatically up‐regulated in our breast cancer specimens and cells (MDA231), especially in metastatic tumor specimens and highly invasive cells, and high lncRNA‐ZEB2‐AS1 expression is associated with clinicopathologic features and short survival of breast cancer patients. LncRNA‐ZEB2‐AS1 promotes the proliferation and metastasis of MDA231 cells in SCID mice. Thus, it is regarded as an oncogene in triple‐negative breast cancer. It is mainly endo‐nuclear and situated near ZEB2, positively regulating ZEB2 expression and activating the epithelial mesenchymal transition via the PI3K/Akt/GSK3β/Zeb2 signaling pathway. Meanwhile, EGF‐induced F‐actin polymerization in MDA231 cells can be suppressed by reducing lncRNA‐ZEB2‐AS1 expression. The migration and invasion of triple‐negative breast cancer can be altered through cytoskeleton rearrangement. In summary, we demonstrated that lncRNA‐ZEB2‐AS1 is an important factor affecting the development of triple‐negative breast cancer and thus a potential oncogene target.

SNMDA: A novel method for predicting microRNA-disease associations based on sparse neighbourhood

miRNAs are a class of small noncoding RNAs that are associated with a variety of complex biological processes. Increasing studies have shown that miRNAs have close relationships with many human diseases. The prediction of the associations between miRNAs and diseases has thus become a hot topic. Although traditional experimental methods are reliable, they could only identify a limited number of associations as they are time‐consuming and expensive. Consequently, great efforts have been made to effectively predict reliable disease‐related miRNAs based on computational methods. In this study, we present a novel approach to predict the potential microRNA‐disease associations based on sparse neighbourhood. Specifically, our method takes advantage of the sparsity of the miRNA‐disease association network and integrates the sparse information into the current similarity matrices for both miRNAs and diseases. To demonstrate the utility of our method, we applied global LOOCV, local LOOCV and five‐fold cross‐validation to evaluate our method, respectively. The corresponding AUCs are 0.936, 0.882 and 0.934. Three types of case studies on five common diseases further confirm the performance of our method in predicting unknown miRNA‐disease associations. Overall, results show that SNMDA can predict the potential associations between miRNAs and diseases effectively.

Novel RNA biomarkers of prostate cancer revealed by RNA-seq analysis of formalin-fixed samples obtained from Russian patients

Due to heterogeneous multifocal nature of prostate cancer (PCa), there is currently a lack of biomarkers that stably distinguish it from benign prostatic hyperplasia (BPH), predict clinical outcome and guide the choice of optimal treatment. In this study RNA-seq analysis was applied to formalin-fixed paraffin-embedded (FFPE) tumor and matched normal tissue samples collected from Russian patients with PCa and BPH. We identified 3384 genes differentially expressed (DE) (FDR < 0.05) between tumor tissue of PCa patients and adjacent normal tissue as well as both tissue types from BPH patients. Overexpression of four of the discovered genes (ANKRD34B, NEK5, KCNG3, and PTPRT) was validated by RT-qPCR. Furthermore, the enrichment analysis of overrepresented microRNA and transcription factor (TF) recognition sites within DE genes revealed common regulatory elements of which 13 microRNAs and 53 TFs were thus linked to PCa for the first time. Moreover, 8 of these TFs (FOXJ2, GATA6, NFE2L1, NFIL3, PRRX2, TEF, EBF2 and ZBTB18) were found to be differentially expressed in this study making them not only candidate biomarkers of prostate cancer but also potential therapeutic targets.