MiR-133a acts as an anti-oncogene in Hepatocellular carcinoma by inhibiting FOSL2 through TGF-β/Smad3 signaling pathway

Salivary exosomal microRNA profile as biomonitoring tool for diagnosis and prognosis of patients with head and neck squamous cell carcinoma: a systematic review

OBJECTIVE

Exosomes are extracellular vesicles found in saliva and other body fluids. These vesicles range in size from 30 to 150 nm and play a crucial role in intercellular communication, transporting different biomolecules, actively targeting cells. These vesicles regulate both physiological and pathological processes within recipient cells. MicroRNAs (miRs) are transported within exosomes and are delivered to target cells where they influence signaling pathways, taking on a crucial regulatory role in oncogenesis; for example, they are implicated in progression and infiltration of various cancers, such as head and neck squamous cell carcinoma (HNSCC).

MATERIAL AND METHODS

A systematic literature search based on specific keywords, according to the PRISMA guidelines, was carried out on PubMed, Web of Science, Scopus, and Google Scholar. Only original articles were selected during this review. The risk of bias was assessed by QUADAS-2.

RESULTS

At the end of the selection process 9 articles were included. In these studies, 41 miRs showed differential expression between healthy subjects and patient with HNSCC. The techniques varied among studies for the extraction and analysis of exosomal miRs. We presented also salivary exosomal miRs pathways, to give insights about pathogenetic mechanisms.

CONCLUSIONS

Exosomal microRNA are promising biomarkers for HNSCC detection. MiR-10b-5p, miR-486-5p, miR-24-3p, miR-412-3p, and miR-512-3p are the most promising markers applicable to diagnostics, while miR-1307-5p and miR-519c-3p resulted overexpressed and correlated to worse survival outcomes.

Role of Fra-2 in cancer

Fos-related antigen-2 (Fra-2) is the most recently discovered member of the Fos family and, by dimerizing with Jun proteins, forms the activator protein 1 (AP-1) transcription factor. By inducing or repressing the transcription of several target genes, Fra-2 is critically involved in the modulation of cell response to a variety of extracellular stimuli, stressors and intracellular changes. In physiological conditions, Fra-2 has been found to be ubiquitously expressed in human cells, regulating differentiation and homeostasis of bone, muscle, nervous, lymphoid and other tissues. While other AP-1 members, like Jun and Fos, are well characterized, studies of Fra-2 functions in cancer are still at an early stage. Due to the lack of a trans-activating domain, which is present in other Fos proteins, it has been suggested that Fra-2 might inhibit cell transformation, eventually exerting an anti-tumor effect. In human malignancies, however, Fra-2 activity is enhanced (or induced) by dysregulation of microRNAs, oncogenes and extracellular signaling, suggesting a multifaceted role. Therefore, Fra-2 can promote or prevent transformation, proliferation, migration, epithelial-mesenchymal transition, drug resistance and metastasis formation in a tumor- and context-dependent manner. Intriguingly, recent data reports that Fra-2 is also expressed in cancer associated cells, contributing to the intricate crosstalk between neoplastic and non-neoplastic cells, that leads to the evolution and remodeling of the tumor microenvironment. In this review we summarize three decades of research on Fra-2, focusing on its oncogenic and anti-oncogenic effects in tumor progression and dissemination.

LncRNA LINC00847 Accelerates Melanoma Progression by Regulating MiR-133a-3p/TGFBR1 Axis

AIMS

Growing evidence has suggested that lncRNAs play a regulatory role in tumorigenesis. Dysregulation of a newly identified lncRNA (LINC00847) has been involved in several tumors. Nevertheless, the expression and roles of lncRNAs in skin melanoma remain unclear. Therefore, we attempted to investigate the expressions and roles of lncRNAs in this study.

MATERIALS AND METHODS

Expression levels of LINC00847 were quantified in tissue samples from the TCGA database and clinically recruited participants. LINC00847 was inhibited in cells by transfecting with si-LINC00847 or si-NC. Expressions of LINC00847 and miR-133a-3p were determined using RT-qPCR, and the TGFBR1 level was determined using Western blotting. Targeting sites of LINC00847 with miR-133a-3p and miR-133a-3p with TGFBR1 were predicted by bioinformatic tools and proved by dual-luciferase reporter system and RNA immunoprecipitation. Cell proliferation, invasion, and migration abilities were assessed using CCK8, cell colony formation, cell wound scratch, and transwell assay, respectively.

RESULTS

In both TCGA and clinical cohorts, the expression of LINC00847 was abnormally upregulated in skin melanoma tissues than that of benign nevus. Besides, LINC00847 expression increased more markedly in A375 and SK-MEL-28 cells than in normal epidermal melanocytes (HEMa-LP cells). LINC00847 knockdown remarkably restrained skin melanoma cell proliferation, metastasis, and wound healing rate. Furthermore, miR-133a-3p/TGFBR1 was the downstream target for LINC00847. LINC00847 negatively regulated miR-133a-3p expression in skin melanoma cells. Both miR-133a-3p inhibitors and TGFBR1 vector transfection reversed the effect of LINC00847 silence in skin melanoma cells.

CONCLUSION

LINC00847 was highly expressed in skin melanoma, and its overexpression accelerated the malignant tumor behavior of skin melanoma cells. The miR-133a-3p /TGFBR1 axis was involved in the roles of LINC00847 in skin melanoma.

The Role of the Transforming Growth Factor-β Signaling Pathway in Gastrointestinal Cancers

Transforming growth factor-β (TGF-β) has attracted attention as a tumor suppressor because of its potent growth-suppressive effect on epithelial cells. Dysregulation of the TGF-β signaling pathway is considered to be one of the key factors in carcinogenesis, and genetic alterations affecting TGF-β signaling are extraordinarily common in cancers of the gastrointestinal system, such as hereditary nonpolyposis colon cancer and pancreatic cancer. Accumulating evidence suggests that TGF-β is produced from various types of cells in the tumor microenvironment and mediates extracellular matrix deposition, tumor angiogenesis, the formation of CAFs, and suppression of the anti-tumor immune reaction. It is also being considered as a factor that promotes the malignant transformation of cancer, particularly the invasion and metastasis of cancer cells, including epithelial-mesenchymal transition. Therefore, elucidating the role of TGF-β signaling in carcinogenesis, cancer invasion, and metastasis will provide novel basic insight for diagnosis and prognosis and the development of new molecularly targeted therapies for gastrointestinal cancers. In this review, we outline an overview of the complex mechanisms and functions of TGF-β signaling. Furthermore, we discuss the therapeutic potentials of targeting the TGF-β signaling pathway for gastrointestinal cancer treatment and discuss the remaining challenges and future perspectives on targeting this pathway.

Molecular biology of microRNA-342 during tumor progression and invasion

Cancer is considered as one of the main causes of human deaths and health challenges in the world. Various factors are involved in the high death rate of cancer patients, including late diagnosis and drug resistance that result in treatment failure and tumor recurrence. Invasive diagnostic methods are one of the main reasons of late tumor detection in cancer patients. Therefore, it is necessary to investigate the molecular tumor biology to introduce efficient non-invasive markers. MicroRNAs (miRNAs) are involved in regulation of the cellular mechanisms such as cell proliferation, apoptosis, and migration. MiRNAs deregulations have been also frequently shown in different tumor types. Here, we discussed the molecular mechanisms of miR-342 during tumor growth. MiR-342 mainly functions as a tumor suppressor by the regulation of transcription factors and signaling pathways such as WNT, PI3K/AKT, NF-kB, and MAPK. Therefore, miR-342 mimics can be used as a reliable therapeutic strategy to inhibit the tumor cells growth. The present review can also pave the way to introduce the miR-342 as a non-invasive diagnostic/prognostic marker in cancer patients.

Chromatin accessibility uncovers KRAS-driven FOSL2 promoting pancreatic ductal adenocarcinoma progression through up-regulation of CCL28

BACKGROUND

The epigenetic mechanisms involved in the progression of pancreatic ductal adenocarcinoma (PDAC) remain largely unexplored. This study aimed to identify key transcription factors (TFs) through multiomics sequencing to investigate the molecular mechanisms of TFs that play critical roles in PDAC.

METHODS

To characterise the epigenetic landscape of genetically engineered mouse models (GEMMs) of PDAC with or without KRAS and/or TP53 mutations, we employed ATAC-seq, H3K27ac ChIP-seq, and RNA-seq. The effect of Fos-like antigen 2 (FOSL2) on survival was assessed using the Kaplan-Meier method and multivariate Cox regression analysis for PDAC patients. To study the potential targets of FOSL2, we performed Cleavage Under Targets and Tagmentation (CUT&Tag). To explore the functions and underlying mechanisms of FOSL2 in PDAC progression, we employed several assays, including CCK8, transwell migration and invasion, RT-qPCR, Western blotting analysis, IHC, ChIP-qPCR, dual-luciferase reporter, and xenograft models.

RESULTS

Our findings indicated that epigenetic changes played a role in immunosuppressed signalling during PDAC progression. Moreover, we identified FOSL2 as a critical regulator that was up-regulated in PDAC and associated with poor prognosis in patients. FOSL2 promoted cell proliferation, migration, and invasion. Importantly, our research revealed that FOSL2 acted as a downstream target of the KRAS/MAPK pathway and recruited regulatory T (Treg) cells by transcriptionally activating C-C motif chemokine ligand 28 (CCL28). This discovery highlighted the role of an immunosuppressed regulatory axis involving KRAS/MAPK-FOSL2-CCL28-Treg cells in the development of PDAC.

CONCLUSION

Our study uncovered that KRAS-driven FOSL2 promoted PDAC progression by transcriptionally activating CCL28, revealing an immunosuppressive role for FOSL2 in PDAC.

Circular RNAs in hepatocellular carcinoma: biogenesis, function, and pathology

Hepatocellular carcinoma (HCC) is one of the most common causes of cancer-related death worldwide. Both genetic and environmental factors through a multitude of underlying molecular mechanisms participate in the pathogenesis of HCC. Recently, numerous studies have shown that circular RNAs (circRNAs), an emerging class of non-coding RNAs characterized by the presence of covalent bonds linking 3' and 5' ends, play an important role in the initiation and progression of cancers, including HCC. In this review, we outline the current status of the field of circRNAs, with an emphasis on the functions and mechanisms of circRNAs in HCC and its microenvironment. We also summarize and discuss recent advances of circRNAs as biomarkers and therapeutic targets. These efforts are anticipated to throw new insights into future perspectives about circRNAs in basic, translational and clinical research, eventually advancing the diagnosis, prevention and treatment of HCC.

MiR-133a/CD47 axis is a novel prognostic biomarker to promote triple negative breast cancer progression

Cluster of differentiation 47 (CD47) acts as an anti-engulfment signal on tumor cells, and its overexpression is correlated with poor prognosis of various malignant tumors. However, the role and mechanism of CD47 in tumor cell proliferation, migration and apoptosis remain unclarified. Emerging evidence indicates that microRNAs (miRNAs) are potential regulators to mediate CD47 generation. In this study, we found that CD47 was up-regulated while miR-133a was down-regulated in triple-negative breast cancer (TNBC) in vitro and in vivo. Moreover, we demonstrated for the first time that CD47 was a direct target of miR-133a in TNBC cells, and provided direct evidence of the inverse correlation between miR-133a and CD47 expression in TNBC. Besides, miR-133a functioned as a tumor suppressor to inhibit proliferation and migration, and promote apoptosis of TNBC cells by targeting CD47. Furthermore, overexpression of miR-133a inhibited the tumor growth of TNBC in an in vivo xenograft animal model by targeting CD47. Thus, miR-133a/CD47 axis provides new insight into the mechanism of TNBC progression and could be a promising candidate in the diagnosis and treatment of TNBC.

The role of miRNAs in liver diseases: Potential therapeutic and clinical applications

MicroRNAs (miRNAs) are a class of short, non-coding RNAs that function post-transcriptionally to regulate gene expression by binding to particular mRNA targets and causing destruction of the mRNA or translational inhibition of the mRNA. The miRNAs control the range of liver activities, from the healthy to the unhealthy. Considering that miRNA dysregulation is linked to liver damage, fibrosis, and tumorigenesis, miRNAs are a promising therapeutic strategy for the evaluation and treatment of liver illnesses. Recent findings on the regulation and function of miRNAs in liver diseases are discussed, with an emphasis on miRNAs that are highly expressed or enriched in hepatocytes. Alcohol-related liver illness, acute liver toxicity, viral hepatitis, hepatocellular carcinoma, liver fibrosis, liver cirrhosis, and exosomes in chronic liver disease all emphasize the roles and target genes of these miRNAs. We briefly discuss the function of miRNAs in the etiology of liver diseases, namely in the transfer of information between hepatocytes and other cell types via extracellular vesicles. Here we offer some background on the use of miRNAs as biomarkers for the early prognosis, diagnosis, and assessment of liver diseases. The identification of biomarkers and therapeutic targets for liver disorders will be made possible by future research into miRNAs in the liver, which will also help us better understand the pathogeneses of liver diseases.

Small Extracellular Vesicles and Their Involvement in Cancer Resistance: An Up-to-Date Review

In recent years, tremendous progress has been made in understanding the roles of extracellular vesicles (EVs) in cancer. Thanks to advancements in molecular biology, it has been found that the fraction of EVs called exosomes or small EVs (sEVs) modulates the sensitivity of cancer cells to chemotherapeutic agents by delivering molecularly active non-coding RNAs (ncRNAs). An in-depth analysis shows that two main molecular mechanisms are involved in exosomal modified chemoresistance: (1) translational repression of anti-oncogenes by exosomal microRNAs (miRs) and (2) lack of translational repression of oncogenes by sponging of miRs through long non-coding RNAs (lncRNAs) and circular RNAs (circRNAs). At the cellular level, these processes increase the proliferation and survival of cancer cells and improve their ability to metastasize and resist apoptosis. In addition, studies in animal models have shown enhancing tumor size under the influence of exosomal ncRNAs. Ultimately, exosomal ncRNAs are responsible for clinically significant chemotherapy failures in patients with different types of cancer. Preliminary data have also revealed that exosomal ncRNAs can overcome chemotherapeutic agent resistance, but the results are thoroughly fragmented. This review presents how exosomes modulate the response of cancer cells to chemotherapeutic agents. Understanding how exosomes interfere with chemoresistance may become a milestone in developing new therapeutic options, but more data are still required.

miR-130b suppresses the invasion and migration of prostate cancer via inhibiting DLL1 and regulating the PI3K/Akt pathways

Prostate cancer occurs in the prostatic epithelium and poses a threat to the health of middle-aged and older males. The objective of the present study was to explore the roles of microRNA (miRNA/miR)-130b in prostate cancer and potential molecular mechanisms in order to control the migration and invasion of prostate cancer. For this purpose, reverse transcription-PCR was performed to evaluate the mRNA levels of DLL1, phosphoinositide-3 kinase (PI3K), protein kinase B (Akt) and matrix metalloproteinase (MMP)9, and western blot analysis was carried out to detect the protein expression levels of DLL1, phosphorylated (p)-PI3K, p-Akt and MMP9. A Transwell assay was conducted to examine the invasion rate of prostate cancer cells. Furthermore, a scratch wound assay was performed to examine the migration rate of prostate cancer cells. A luciferase assay was performed to examine the interaction between miRNA and its target mRNA. The results revealed that miR-130b had abnormal (low) expression in tumor tissues compared with that in the adjacent normal tissue. An miR-130b mimic suppressed the expression of DLL1. The expression of p-PI3K, p-Akt and MMP9 in prostate cancer cells transfected with the miR-130b mimic was decreased in comparison to the negative control and control groups. Furthermore, migration and invasion were significantly suppressed in the miR-130b mimic group. In conclusion, a novel pathway interlinking miR-130b and MMP9, p-Akt and p-PI3K, which regulates the migration and invasion of prostate cancer cells, was identified. These findings provide an intriguing biomarker and treatment strategy for patients with prostate cancer.

The miR-133a, TPM4 and TAp63γ Role in Myocyte Differentiation Microfilament Remodelling and Colon Cancer Progression

MicroRNAs (miRNAs) play an essential role in the regulation of a number of physiological functions. miR-133a and other muscular miRs (myomiRs) play a key role in muscle cell growth and in some type of cancers. Here, we show that miR133a is upregulated in individuals that undertake physical exercise. We used a skeletal muscle differentiation model to dissect miR-133a's role and to identify new targets, identifying Tropomyosin-4 (TPM4). This protein is expressed during muscle differentiation, but importantly it is an essential component of microfilament cytoskeleton and stress fibres formation. The microfilament scaffold remodelling is an essential step in cell transformation and tumour progression. Using the muscle system, we obtained valuable information about the microfilament proteins, and the knowledge on these molecular players can be transferred to the cytoskeleton rearrangement observed in cancer cells. Further investigations showed a role of TPM4 in cancer physiology, specifically, we found that miR-133a downregulation leads to TPM4 upregulation in colon carcinoma (CRC), and this correlates with a lower patient survival. At molecular level, we demonstrated in myocyte differentiation that TPM4 is positively regulated by the TA isoform of the p63 transcription factor. In muscles, miR-133a generates a myogenic stimulus, reducing the differentiation by downregulating TPM4. In this system, miR-133a counteracts the differentiative TAp63 activity. Interestingly, in CRC cell lines and in patient biopsies, miR-133a is able to regulate TPM4 activity, while TAp63 is not active. The downregulation of the miR leads to TPM4 overexpression, this modifies the architecture of the cell cytoskeleton contributing to increase the invasiveness of the tumour and associating with a poor prognosis. These results add data to the interesting question about the link between physical activity, muscle physiology and protection against colorectal cancer. The two phenomena have in common the cytoskeleton remodelling, due to the TPM4 activity, that is involved in stress fibres formation.

Circ_0091581 Promotes the Progression of Hepatocellular Carcinoma Through Targeting miR-591/FOSL2 Axis

BACKGROUND

Circular RNAs (circRNAs) have shown crucial regulatory roles in cancer biology. We aimed to uncover the role and underlying mechanism of circ_0091581 in hepatocellular carcinoma (HCC) progression.

METHODS

The abundance of circ_0091581, microRNA-591 (miR-591) and FOS like 2, AP-1 transcription factor subunit (FOSL2) was measured by quantitative real-time polymerase chain reaction. Cell viability, colony formation ability, and invasion ability were assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, colony formation assay, and transwell invasion assay. The migration ability was analyzed by transwell migration assay and wound healing assay. Flow cytometry was used to evaluate the cell cycle and apoptosis of HCC cells. The interaction between miR-591 and circ_0091581 or FOSL2 was predicted by Circular RNA Interactome database or TargetScan database and confirmed by dual-luciferase reporter assay and RNA immune co-precipitation assay. FOSL2 protein expression was measured by Western blot assay. Xenograft tumor assay was conducted to analyze the role of circ_0091581 in HCC tumor growth in vivo.

RESULTS

Circ_0091581 was highly expressed in HCC tissue samples and cell lines in contrast to that in adjacent normal tissue samples and THLE-2 cell line. Circ_0091581 accelerated the viability, colony formation, metastasis, and cell cycle, while it impeded the apoptosis of HCC cells. MiR-591 bound to circ_0091581, and circ_0091581 knockdown-mediated effects in HCC cells were largely overturned by miR-591 silencing. FOSL2 was a target of miR-591, and FOSL2 overexpression largely reversed miR-591 accumulation-induced influences in HCC cells. FOSL2 protein expression was down-regulated by circ_0091581 silencing, and the addition of miR-591 inhibitor partly recovered the expression of FOSL2 in HCC cells. Circ_0091581 interference notably suppressed HCC tumor growth in vivo.

CONCLUSION

Circ_0091581 acted as an oncogene to enhance the viability, colony formation, metastasis and cell cycle and inhibit the apoptosis of HCC cells through targeting miR-591/FOSL2 axis.

Mechanism of TCONS_00147848 regulating apoptosis of nasal mucosa cells and alleviating allergic rhinitis through FOSL2-mediated JAK/STAT3 signaling pathway

This study was conducted to explore the roles and related mechanisms of lncRNA-TCONS_00147848 (TCONS_00147848) in nasal mucosa cell apoptosis and allergic rhinitis (AR). AR mice were sensitized with ovalbumin (OVA), with the TCONS_00147848 interference lentiviral vector (TCONS_00147848 shRNA) and FOSL2 overexpressing lentiviral vectors (pCDH-FOSL2) constructed respectively. NC shRNA, TCONS_00147848 shRNA and TCONS_00147848 shRNA + pCDH-FOSL2 were transfected into AR mice and mice with TNF-α induced nasal mucosa cells. The allergic reaction symptoms were evaluated by scoring. And in this study, we used Hematoxylin–Eosin (HE) staining and Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) to detect the histological changes of nasal mucosa and apoptosis of nasal mucosa epithelial cells in mice, cell counting kit-8 (CCK-8) assay, Transwell and annexin V/PI to detect proliferation, migration and apoptosis of nasal mucosa cells of mice, respectively, enzyme-linked immunosorbent assay (ELISA) to detect the expression of inflammatory factors, qRT-PCR to detect TCONS_00147848 expression, Western blot assay to detect the expressions of FOSL2, JAK-2, STAT3, p-STAT3, BAX and BCL-2, RNA-binding protein immunoprecipitation (RIP) assay, RNA pull down assay and Co-immunoprecipitation (CoIP) assay to identify TCONS_00147848 targeting FOSL2. All these findings above reveal that knocking down TCONS_00147848 can reduce the allergic reaction symptom score of AR mice and the inflammatory reaction. The expression of IgE, IL-4, IL-5, IL-10, IL-9, IFN-γ and TNF-α in serum decreased. The expression of FOSL2, JAK-2, p-STAT3 and BAX in nasal mucosa and nasal mucosa cells of mice decreased as well, but BCL-2 expression increased. In addition, koncking down TCONS_00147848 can also inhibit the apoptosis of TNF-α induced nasal mucosa cells in mice and promote cell proliferation and migration. However, FOSL2 overexpression neutralized the effect of TCONS_00147848 shRNA. In nasal mucosa cells of mice, TCONS_00147848 can target FOSL2, interacting with STAT3. Inhibition of TCONS_00147848 can regulate JAK/STAT3 signaling pathway and reduce inflammatory response in AR mice.

EphA2 super-enhancer promotes tumor progression by recruiting FOSL2 and TCF7L2 to activate the target gene EphA2

Super-enhancers or stretch enhancers (SEs) consist of large clusters of active transcription enhancers which promote the expression of critical genes that define cell identity during development and disease. However, the role of many super-enhancers in tumor cells remains unclear. This study aims to explore the function and mechanism of a new super-enhancer in various tumor cells. A new super-enhancer that exists in a variety of tumors named EphA2-Super-enhancer (EphA2-SE) was found using multiple databases and further identified. CRISPR/Cas9-mediated deletion of EphA2-SE results in the significant downregulation of its target gene EphA2. Mechanistically, we revealed that the core active region of EphA2-SE comprises E1 component enhancer, which recruits TCF7L2 and FOSL2 transcription factors to drive the expression of EphA2, induce cell proliferation and metastasis. Bioinformatics analysis of RNA-seq data and functional experiments in vitro illustrated that EphA2-SE deletion inhibited cell growth and metastasis by blocking PI3K/AKT and Wnt/β-catenin pathway in HeLa, HCT-116 and MCF-7 cells. Overexpression of EphA2 in EphA2-SE-/- clones rescued the effect of EphA2-SE deletion on proliferation and metastasis. Subsequent xenograft animal model revealed that EphA2-SE deletion suppressed tumor proliferation and survival in vivo. Taken together, these findings demonstrate that EphA2-SE plays an oncogenic role and promotes tumor progression in various tumors by recruiting FOSL2 and TCF7L2 to drive the expression of oncogene EphA2.

FOSL2 promotes VEGF-independent angiogenesis by transcriptionnally activating Wnt5a in breast cancer-associated fibroblasts

Cancer-associated fibroblasts (CAFs), a predominant component of the tumor microenvironment, contribute to aggressive angiogenesis progression. In clinical practice, traditional anti-angiogenic therapy, mainly anti-VEGF, provides extremely limited beneficial effects to breast cancer. Here, we reveal that FOS-like 2 (FOSL2), a transcription factor in breast CAFs, plays a critical role in VEGF-independent angiogenesis in stromal fibroblasts.

Methods: FOSL2 and Wnt5a expression was assessed by qRT-PCR, western blotting and immunohistochemistry in primary and immortalized CAFs and clinical samples. FOSL2- or Wnt5a-silenced CAFs and FOSL2-overexpressing NFs were established to explore their proangiogenic effects. Invasion, tubule formation, three-dimensional sprouting assays, and orthotopic xenografts were conducted as angiogenesis experiments. FZD5/NF-κB/ERK signaling activation was evaluated by western blotting after blocking VEGF/VEGFR with an anti-VEGF antibody and axitinib. Dual luciferase reporter assays and chromatin immunoprecipitation were performed to test the role of FOSL2 in regulating Wnt5a expression, and Wnt5a in the serum of the patients was measured to assess its clinical diagnostic value for breast cancer patients.

Results: Enhanced FOSL2 in breast CAFs was significantly associated with angiogenesis and clinical progression in patients. The supernatant from CAFs highly expressing FOSL2 strongly promoted tube formation and sprouting of human umbilical vein endothelial cells (HUVECs) in a VEGF-independent manner and angiogenesis as well as tumor growth in vivo. Mechanistically, the enhanced FOSL2 in CAFs was regulated by estrogen/cAMP/PKA signaling. Wnt5a, a direct target of FOSL2, specifically activated FZD5/NF-κB/ERK signaling in HUVECs to promote VEGF-independent angiogenesis. In addition, a high level of Wnt5a was commonly detected in the serum of breast cancer patients and closely correlated with microvessel density in breast tumor tissues, suggesting a promising clinical value of Wnt5a for breast cancer diagnostics.

Conclusion: FOSL2/Wnt5a signaling plays an essential role in breast cancer angiogenesis in a VEGF-independent manner, and targeting the FOSL2/Wnt5a signaling axis in CAFs may offer a potential option for antiangiogenesis therapy.

Emerging roles of MiR-133a in human cancers

MicroRNAs (miRNAs) can post-transcriptionally regulate the expression of cancer-relevant genes via binding to the 3'-untranslated region (3'-UTR) of the target mRNAs. MiR-133a, as a miRNA, participate in tumorigenesis, progression, autophagy and drug-resistance in various malignancies. Based on the recent insights, we discuss the functions of miR-133a in physiological and pathological processes and its potential effects on cancer diagnosis, prognosis and therapy.

Hsa_circ_0001869 promotes NSCLC progression via sponging miR-638 and enhancing FOSL2 expression

Accumulating studies suggest that circular RNAs (circRNAs) function as key regulators in human cancers. We found that hsa_circ_0001869 participated in non-small cell lung cancer (NSCLC) progression. However, its expression and function during NSCLC remain unknown. The data advised that hsa_circ_0001869 expression was increased in NSCLC cell lines and tissues. High hsa_circ_0001869 expression had negatively correlation with the NSCLC patients prognosis. Bioinformatics and luciferase report analyses confirmed that miR-638 and FOSL2 were hsa_circ_0001869 downstream target. hsa_circ_0001869 downregulation decreased tumor proliferation, invasion and migration by promoting miR-638 expression and decreasing FOSL2 expression. As a result of overexpression of FOSL2 or silencing of miR-638, the recovery of proliferation, migration, and invasion after hsa_circ_0001869 silencing. Overexpression of FOSL2 also led to recovery of migration, invasion and proliferation after upregulation of miR-638. In vivo studies confirmed that overexpression of FOSL2 or silencing of miR-638 led to the recovery of tumor growth ability regarding A549 cells after hsa_circ_0001869 knockdown. Present investigation discovered that hsa_circ_0001869 enhanced NSCLC progression via sponging miR-638 and promoting FOSL2 expression. hsa_circ_0001869 downregulation suppressed tumor growth and invasion ability.

MiR-133a acts as a tumor suppressor in lung cancer progression by regulating the LASP1 and TGF-β/Smad3 signaling pathway

BACKGROUND

MiR-133a has been confirmed to be involved in the development of multiple cancers including non-small cell lung cancer (NSCLC). However, the precise molecular mechanism has not yet been fully elucidated. The purpose of this study was to investigate the functional role and underlying mechanism of miR-133a in the progression of NSCLC.

METHODS

Quantitative real-time PCR (qRT-PCR) was performed to measure miR-133a and LASP1 expression in NSCLC tissues and cells. 3-(4, 5-dimethyl-2-thiazolyl)-2, 5-diphenyl-2H-tetrazolium bromide (MTT) assay was used to detect cell viability. The protein levels were measured by western blot. The tumor growth was measured by xenograft tumor formation assay.

RESULTS

miR-133a was significantly decreased while LASP1 was increased in NSCLC tissues and cells compared with control groups. Moreover, overexpression of miR-133a suppressed cell viability, whereas miR-133a knockdown enhanced the viability of A549 cells. More importantly, LASP1 was verified as a direct target of miR-133a. Moreover, overexpression of miR-133a inhibited the epithelial-mesenchymal transition (EMT) and TGF-β/Smad3 pathways by regulating LASP1 in vitro. In addition, miR-133a mimic suppressed tumor growth by modulating the TGF-β/Smad3 pathway in vivo.

CONCLUSIONS

In conclusion, miR-133a acted as a tumor suppressor in lung cancer progression by regulating the LASP1 and TGF-β/Smad3 signaling pathway.

Upregulation of miR-133a-3p enhances Bufothionine-induced gastric cancer cell death by modulating IGF1R/PI3K/Akt signal pathway mediated ER stress

AIMS

Bufothionine had been used for gastric cancer (GC) treatment, and this study managed to uncover the underlying mechanisms.

MATERIALS AND METHODS

Cell proliferation was determined by CCK-8 assay and colony formation assay. Flow cytometry (FCM) and TUNEL assay were used to measure cell apoptosis ratio. Intracellular ROS was measured by DCFH-DA probes. qRT-PCR was used to determine miRNAs levels. Western Blot was performed to probe proteins. Dual-luciferase reporter gene system was employed to validate the binding sites of miR-133a-3p and 3'UTR regions of IGF1R mRNA. Immunohistochemistry (IHC) was used to determine the expressions of Ki-67 in mice tumor tissues.

KEY FINDINGS

Bufothionine inhibited cell viability, triggered ER stress and promoted ROS production in GC cells, and both ER stress inhibitor Salburinal (Sal) and ROS scavenger (NAC) abrogated Bufothionine induced GC cell death. Besides, miR-133a-3p was upregulated by Bufothionine, and Bufothionine-induced cell death was enhanced by miR-133a-3p overexpression while alleviated by miR-133a-3p knockdown. Furthermore, miR-133a-3p inactivated PI3K/Akt signal pathway by sponging IGF1R, and Bufothionine inhibited insulin-like growth factor 1 receptor (IGF1R) and inactivated PI3K/Akt cascade by upregulating miR-133a-3p. Notably, the promoting effects of overexpressed miR-133a-3p on Bufothionine-induced GC cell death were abrogated by overexpressing IGF1R, and aggravated by the PI3K/Akt cascade inhibitor (LY294002).

SIGNIFICANCE

Bufothionine promoted GC cell death by triggering miR-133a-3p/IGF1R/PI3K/Akt axis mediated ER stress and ROS production.

Hsa_circ_0003998 promotes epithelial to mesenchymal transition of hepatocellular carcinoma by sponging miR-143-3p and PCBP1

BACKGROUND

Circular RNAs (circRNAs) play a critical regulatory role in cancer progression. However, the underlying mechanisms of circRNAs in hepatocellular carcinoma (HCC) metastasis remain mostly unknown.

METHODS

Has_circ_0003998 (circ0003998) was identified by RNAs sequencing in HCC patients with /without portal vein tumor thrombus (PVTT) metastasis. The expression level of circ0003998 was further detected by in situ hybridization on tissues microarray (ISH-TMA) and qRT-PCR in 25 HCC patients with PVTT metastasis. Moreover, the 25 HCC patients with PVTT metastasis and 50 HCC patients without PVTT metastasis were recruited together to analyze the correlation between circ0003998 expression and HCC clinical characteristics. Transwell, migration and CCK8 assays, as well as nude mice model of lung or liver metastasis were used to evaluate the role of circ0003998 in epithelial to mesenchymal transition (EMT) in HCC. The regulatory mechanisms of circ0003998 in miR-143-3p and PCBP1 were determined by dual-luciferase reporter assay, nuclear-cytoplasmic fractionation, fluorescent in situ hybridization, RNA pull- down, microRNA sequence, western blot and RNA immunoprecipitation.

RESULTS

Compared with adjacent normal liver tissues (ANL), circ0003998 expression was significantly upregulated in PVTT tissues and HCC tissues, and its expression correlates with the aggressive characteristics of HCC patients. Further assays suggested that circ0003998 promoted EMT of HCC both in vitro and in vivo. Mechanistically, our data indicated that circ0003998 may act as a ceRNA (competing endogenous RNA) of microRNA-143-3p to relieve the repressive effect on EMT-related stimulator, FOSL2; meanwhile, circ0003998 could bind with PCBP1-poly(rC) binding protein 1 (PCBP1) to increase the expression level of EMT-related genes, CD44v6.

CONCLUSION

Circ0003998 promotes EMT of HCC by circ0003998/miR-143-3p/FOSL2 axis and circ0003998 /PCBP1/CD44v6 axis.

LncRNA LINC00313 Knockdown Inhibits Tumorigenesis and Metastasis in Human Osteosarcoma by Upregulating FOSL2 through Sponging miR-342-3p

PURPOSE

Osteosarcoma (OS) is the most common primary bone tumor, with high morbidity in infants and adolescents. Long noncoding RNA LINC00313 has been found to modulate papillary thyroid cancer tumorigenesis and to be dysregulate in lung cancer. However, the role of LINC00313 in OS has not yet been addressed.

MATERIALS AND METHODS

We evaluated mRNA and protein expression using real-time quantitative PCR and Western blotting. Cell proliferation was evaluated using MTT; apoptosis and autophagy were assessed with flow cytometry, Western blotting, and/or GFP-LC3 assay. Transwell assay was conducted to measure cell migration and invasion. Potential target sites for LINC00313 and miR-342-3p were predicted with starBase v.2.0 and TargetScan Human, and verified using luciferase reporter assay, RNA immunoprecipitation, and RNA pull-down assay. In vivo, xenogeneic tumors were induced with U2OS and MG-63 cells, separately.

RESULTS

LINC00313 was upregulated and miR-342-3p was downregulated in OS tissues and cells. High expression of LINC00313 was associated with shorter overall survival. FOSL2 downregulation and miR-342-3p overexpression suppressed cell proliferation and migratory and invasive abilities while promoting apoptosis and autophagy, all of which were consistent with the effects of LINC00313 knockdown. miR-342-3p, sponged by LINC00313, inversely modulated FOSL2 by targeting MG-63 cells, and FOSL2 expression was positively controlled by LINC00313. LINC00313 knockdown suppressed tumor growth in vivo.

CONCLUSION

LINC00313 is upregulated in OS, and LINC00313 knockdown plays a vital anti-tumor role in OS cell progression through a miR-342-3p/FOSL2 axis. Our study suggests that LINC00313 may be a novel, promising biomarker for diagnosis and prognosis of OS.

Overexpression of miR-133a-3p inhibits fibrosis and proliferation of keloid fibroblasts by regulating IRF5 to inhibit the TGF-β/Smad2 pathway

AIM

Keloid is a benign dermal tumor with excessive hyperplasia and deposition of collagen. As a common tumor suppressor gene, miR-133a-3p has not been studied in keloid. This study will delve into the specific mechanism of miR-133a-3p in keloid.

METHODS

Normal skin fibroblasts and keloid fibroblasts (KFs) were first isolated from patients' normal skin and keloid, and cells were identified by morphological observation and immunofluorescence. The expressions of miR-133a-3p and extracellular matrix (ECM)-associated markers (Collagen I, III and α smooth muscle activin) were detected by Quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). Cell viability and apoptosis of KFs were examined by Cell Counting Kit-8 assay, flow cytometry, and Caspase-3 colorimetry. TargetScan predicted target gene for miR-133a-3p was verified by luciferase assay, qRT-PCR and Western Blot (WB). WB was used to study protein expression of TGFBR1, phosphorylated -Smad2 (p-Smad2) and Smad2. Finally, a series of rescue experiments were performed to verify the intervention of target genes on miR-133a-3p.

RESULTS

MiR-133a-3p was lowly expressed in keloid tissue and KFs. Overexpression of miR-133a-3p inhibited the expression of ECM-associated markers, reduced KFs viability, and promoted apoptosis. It was verified that interference regulator 5 (IRF5) is miR-133a-3p target gene. The rescue experiments showed that IRF5 reversed the effect of miR-133a-3p mimic on inhibiting fibrosis, and reversed the effects on promoting apoptosis and reducing cell proliferation.

CONCLUSION

Overexpressed miR-133a-3p inhibits fibrosis by down-regulating IRF5 and thus inhibiting the TGF-β/Smad2 pathway. And it also promotes KFs apoptosis and reduces proliferation.

Association between Single-Nucleotide Polymorphism in MicroRNA Target Site of DDB2 and Risk of Hepatocellular Carcinoma in a Southern Chinese Population

Damage-specific DNA-binding protein 2 (DDB2) is a DNA repair protein mainly involved in nucleotide excision repair, which plays a pivotal role in maintaining genomic stability. In this study, we evaluated the association of single-nucleotide polymorphism (SNP) rs1050244 in miRNA target site of DDB2 gene with risk of hepatocellular carcinoma (HCC) among 1073 HCC patients and 1119 cancer-free controls in a southern Chinese population. Our results showed that no statistically significant association was found between DDB2 rs1050244 and HCC risk. In further analysis stratified by age, sex, smoking, alcohol drinking, and HBV infection status, we found that individuals carrying the CT/TT genotypes of SNP rs1050244 had a significantly decreased risk of HCC compared with those with the CC genotype among non-HBV infected population (adjusted OR = 0.31, 95% CI = 0.13–0.72), and a significant interaction was found between this SNP and HBV infection (P_interaction=0.002). Our results suggested that the DDB2 rs1050244 C>T polymorphism was associated with the decreased risk of HCC among non-HBV infected population. Further studies with larger sample sizes are needed to validate our findings.

Circular RNA hsa_circ_0056836 functions an oncogenic gene in hepatocellular carcinoma through modulating miR-766-3p/FOSL2 axis

BACKGROUND

Circular RNA (circRNA) remains a tumour-related factor in various biological cells and plays regulatory roles in gene expression. It is a type of non-coding RNA, whereas the function of human circRNA in hepatocellular carcinoma (HCC) is still not clear yet. Our investigation used the HCC cell line to uncover the biological function of hsa_circ_0056836 in the development and progression of hepatocellular carcinoma.

RESULTS

The present study showed that hsa_circ_0056836 revealed high expressions in HCC cell lines and tissues compared with corresponding controls. Silencing of Hsa_circ_0056836 decreased cell migration, proliferation and invasion. Silencing of hsa_circ_0056836 inhibited the development of HCC in xenograft nude mice. Mechanistically, we found that hsa_circ_0056836 directly bound to miR-766-3p, thereby alleviating the targeted inhibition of Fos-related antigen 2 (FOSL2). The results of this study indicated that hsa_circ_0056836 is a novel oncogenic RNA of vast potential as a tumor biomarker.

CONCLUSION

In summary, the hsa_circ_0056836 / miR-766-3p / FOSL2 axis may serve as a promising strategy for HCC treatment.

METHOD

First, the expressions of hsa_circ_0056836 in HCC tissues and corresponding para-cancerous tissues as well as in HCC cell lines and normal hepatocytes THLE-3 were detected by RT-PCR. Subcellular localization of hsa_circ_0056836 was confirmed by FISH. To detect the association between hsa_circ_0056836 and miR-766-3p, AGO2-RIP and Luciferase reporter assay were adopted. Loss of function study was applied to assess the role of hsa_circ_0056836 in HCC and to determine tumorigenesis in nude mice.

HGF/MET Regulated Epithelial-Mesenchymal Transitions And Metastasis By FOSL2 In Non-Small Cell Lung Cancer

Background

HGF/MET has been found to be associated with non-small cell lung cancer (NSCLC). However, the underlying molecular mechanisms of HGF/MET involved in regulating the metastasis of NSCLC remain unclear.

Methods

The effect of HGF/MET and FOSL2 on cell migration and invasion were assessed by transwell and scratch assays. HGF/MET-induced phosphorylation and upregulation of FOSL2 was analyzed by RT-PCR and Western blotting. Regulatory effects of FOSL2 on SNAI2 transcription were detected by chromatin immunoprecipitation (ChIP) and dual-Luciferase reporter assays. The correlations of FOSL2 expression with clinical outcomes were assessed in 56 NSCLC patients.

Results

HGF/MET induced the phosphorylation and upregulation of FOSL2 by ERK1/2 kinase, FOSL2 promoted the transcription of SNAI2 by binding with the SNAI2 promoter, and SNAI2 subsequently promoted the epithelial-mesenchymal transition (EMT), invasion, and migration of NSCLC cells. According to the clinical correlation analysis in NSCLC, high expression of FOSL2 correlated with advanced tumor stage and metastasis.

Conclusion

Our studies propose that the regulatory mechanisms of the HGF/MET-induced cascade pathway is mediated by FOSL2 in NSCLC metastasis and suggested that FOSL2 could potentially be employed as a prognostic biomarker and potential therapeutic target of NSCLC metastasis.

MicroRNA-133a inhibits the proliferation of non-small cell lung cancer by targeting YES1

Previous studies have reported that microRNA-133a (miR-133a) is involved in the pathogenesis of human cancers. This study investigated the effect of miR-133a on cell proliferation in non-small cell lung cancer (NSCLC). The expression of miR-133a and YES proto-oncogene 1 (YES1) was detected using reverse transcription-quantitative polymerase chain reaction (RT-qPCR) assay. The CCK-8 assay was used to measure cell proliferation. The relationship between miR-133a and YES1 was confirmed by dual luciferase assay. Downregulation of miR-133a was identified in NSCLC and correlated with poor prognosis in NSCLC patients. Moreover, the overexpression of miR-133a inhibited proliferation of NSCLC cells. YES1 was also confirmed as a direct target of miR-133a. Downregulation of YES1 was found to inhibit cell proliferation in NSCLC. By contrast, the upregulation of YES1 abolished the inhibitory effect of miR-133a on cell proliferation in NSCLC. miR-133a inhibited cell proliferation in NSCLC by targeting YES1, indicating that miR-133a can be used as an indicator of prognosis in NSCLC patients.

MiR-449b-5p regulates cell proliferation, migration and radioresistance in cervical cancer by interacting with the transcription suppressor FOXP1

MicroRNAs (miRNAs) have been acknowledged as crucial regulators for the malignant progression of human cancers. However, the molecular mechanism associated with the malignant progression of cervical cancer (CC) is still largely unmarked. The focus of this study is to explore the potential functional mechanism of miR-449b-5p in CC. Using qRT-PCR analysis, we detected a relative lower expression level of miR-449b-5p in CC tissues and cell lines by comparing with the normal tissues and cells. Low level of miR-449b-5p in CC cell lines was further demonstrated by northern blot. Subsequently, downregulation of miR-449b-5p was closely correlated with the low overall survival rate of patients with cervical cancer. Gain-of-function assays demonstrated that upregulation of miR-449b-5p had an inhibitory effect on cell proliferation, migration and invasion. Moreover, FOXP1 was found to be a transcription suppressor and downstream target of miR-449b-5p. Rescue assays and in vivo experiment were applied to demonstrate the biological function of miR-449b-5p-FOXP1 feedback loop. In summary, miR-449b-5p interacted with FOXP1 to regulate cell proliferation, migration, invasion and radiosensitivity in CC.

miR-584-5p regulates hepatocellular carcinoma cell migration and invasion through targeting KCNE2

BACKGROUND

Hepatocellular carcinoma (HCC) is one of the most commonly diagnosed cancer type. This study was aimed to investigate the role of microRNA-584-5p (miR-584-5p) in regulating HCC progression.

METHODS

The expression of miR-584-5p in HCC cell lines was analyzed by quantitative real-time polymerase chain reaction. Effects of miR-584-5p depletion on HCC cell proliferation, migration, and invasion in vitro were analyzed by cell counting kit-8 assay, wound-healing assay, and transwell invasion assay. miR-584-5p targeting potassium voltage-gated channel subfamily E regulatory subunit 2 (KCNE2) was identified using bioinformatics algorithm and dual-luciferase activity reporter assay. Kaplan-Meier Plotter website was used to investigate the effect of miR-584-5p or KCNE2 expression on the overall survival of HCC patients.

RESULTS

In vitro functional assays showed miR-584-5p depletion decreased HCC cell proliferation, cell migration, and cell invasion. Moreover, miR-584-5p functions by directly targeting KCNE2, and it in turn, mediates the effects of miR-584-5p on HCC cell behaviors.

CONCLUSIONS

These results demonstrated that miR-584-5p functions as an oncogenic miRNA in HCC.

Recent advances in the molecular mechanism of sex disparity in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is more frequently observed and aggressive in men compared with women. Increasing evidence demonstrates that the sex disparity appears to be mediated by the stimulatory effects of androgens and the protective effects of estrogen in the development and progression of HCC. In the past few decades, studies on the sex difference of HCC mainly focused on the effect of sex hormones on the transactivation of hepatitis B virus X protein and the release of inflammatory cytokines, and these studies have further intensified in recent years. Sex hormones are also involved in genetic alterations and DNA damage repair in hepatocytes through binding to their specific cellular receptors and affecting the corresponding signaling pathways. Furthermore, the theory of sex chromosomes participating in HCC has been considered. The present review discussed the recent advances in the molecular mechanisms of sex disparity in HCC, with the aim of improving the understanding of the underlying critical factors and exploring more effective methods for the prevention and treatment of HCC.

Silencing TRIP13 inhibits cell growth and metastasis of hepatocellular carcinoma by activating of TGF-β1/smad3

Background

TRIP13 is highly expressed in several cancers and is closely connected with cancer progression. However, its roles on the growth and metastasis of hepatocellular carcinoma (HCC), and the underlying mechanism are still unclear.

Methods

Combining bioinformatics with previous studies, the correlation between TRIP13 and HCC was predicted. TRIP13 expressions from 52 HCC patients and several cell lines were determined. The effects of silencing TRIP13 on cell viability, apoptosis, migration and invasion were respectively detected using CCK-8, flow cytometry and Transwell. qRT-PCR and western blot were performed to reveal associated mechanism. A HCC model was established in BALB/c-nu mice by transplanting HepG2 cells. TRIP13 protein expression and apoptosis in mice tissues were accordingly detected by Immunohistochemistry and TUNEL.

Results

High expression of TRIP13 in HCC affected the survival rate and it was enriched in RNA degradation and fatty acid metabolism according to bioinformatics and prediction from previous literature. Increased expression of TRIP13 in HCC patient tissues was associated with the progression of HCC. Silencing TRIP13 inhibited cell viability, migration and invasion, and induced cell apoptosis. TRIP13 knockdown also suppressed the formation of tumor in vivo. Meanwhile, silencing TRIP13 decreased the expressions of Ki67 and MMP-2 and increased the expressions of TIMP-2, active-caspase-3 and TGF-β1/smad3 signaling- related genes.

Conclusions

Silencing TRIP13 acts as a tumor suppresser of HCC to repress cell growth and metastasis in vitro and in vivo, and such a phenomenon possibly involved activation of TGF-β1/smad3 signaling.