miRNA-495 suppresses proliferation and migration of colorectal cancer cells by targeting FAM83D

The role of HM13 expression and its relationship to PI3K/Akt and p53 signaling pathways in colorectal cancer

Histocompatibility minor 13 (HM13) is a signal sequence stubbed intramembrane cleavage catalytic protein. Increasing evidence supports the association among HM13 expression, tumor-infiltrating immune cells (TIICs), and cancer. However, its role on formation and progression of colorectal cancer (CRC) has not been explored. In this study, we aim to identify the role and function of HM13 on the progression of CRC and explore the possible mechanism. The findings of our study indicate that HM13 is significantly upregulated in colorectal cancer (CRC) compared to normal colorectal tissues (P< 0.001). Moreover, the elevated expression of HM13 is associated with unfavorable prognosis in CRC patients. Furthermore, our results demonstrate that the overexpression of HM13 contributes to enhanced proliferation and migration, as well as suppressed apoptosis, in SM480 and HCT116 cell lines (P<0.001). Conversely, the downregulation of HM13 (shHM13) yields opposite effects. Additionally, the administration of LY294003 and nutlin-3 effectively inhibits proliferation and migration, while promoting apoptosis in HCT116 cells (P<0.001). However, the presence of HM13 counteracts these changes. In an in vivo study, the knockdown of HM13 (shHM13) significantly reduces tumor growth and the proportion of Ki-67 positive cells, while increasing the percentage of tunel-positive cells (P<0.001). Also, shHM13 decreased the level of p-PI3K/PI3K and p-AKT/AKT, upregulated p53 and p21 activities. It can thus be concluded that HM13 might be a novel oncogene in CRC and regulates proliferation, migration and apoptosis by modulating the PI3K/Akt and p53 signaling pathways.

SATB1 in cancer progression and metastasis: mechanisms and therapeutic potential

Cancer remains a major global health challenge, with prostate cancer, lung cancer, colorectal cancer, and breast cancer accounting for nearly half of all diagnoses. Despite advancements in cancer treatment, metastasis to distant organs continues to be the leading cause of cancer-related mortality. The progression of cancer involves the alteration of numerous genes, with dynamic changes in chromatin organization and histone modifications playing a critical role in regulating cancer-associated genes. Special AT-rich sequence-binding protein 1 (SATB1), a critical chromatin organizer, plays a pivotal role in cancer progression by regulating gene expression, chromatin remodeling, and cell signaling pathways. SATB1 binds to AT-rich DNA sequences, acting as a scaffold for chromatin-modifying enzymes and transcription factors, thus coordinating the regulation of extensive gene networks. Its overexpression has been implicated in a wide range of cancers and is associated with poor prognosis, aggressive tumor phenotypes, and enhanced epithelial-mesenchymal transition (EMT). Moreover, SATB1's activity is modulated by microRNAs (miRNAs) and post-translational modifications, further contributing to its complex regulatory functions. Given its crucial involvement in cancer progression and metastasis, SATB1 has emerged as a promising target for novel therapeutic strategies. This review delves into the molecular mechanisms of SATB1 in cancer and explores potential therapeutic approaches for targeting this key regulator in cancer treatment.

Functional Three-Dimensional Zeolitic Imidazolate Framework with an Ordered Macroporous Structure for the Isolation of Extracellular Vesicles

Extracellular vesicles (EVs) and their cargoes are increasingly being recognized as noninvasive diagnostic markers, necessitating the isolation of EVs from complex biological samples. Herein, a distearoyl phospholipid ethanolamine-functionalized single-crystal ordered macroporous three-dimensional zeolitic imidazolate framework (SOM-ZIF-8-DSPE) was developed, which combines the surface charge interaction of ZIF-8 with the synergistic effect of DSPE insertion into the phospholipid membrane of EVs to improve the isolating selectivity of EV capture. The materials have porous structures larger than 300 nm in diameter, providing enough space and active sites to trap EVs. Benefiting from this feature, the entire isolation process takes only 10 min and is well compatible with the subsequent analysis of RNA in EVs. Consequently, 10 upregulated miRNA of plasma EVs in the primary colorectal cancer (pCRC) patients is found over the healthy donors, and 6 upregulated miRNA of plasma EVs in the metastatic colorectal cancer (mCRC) patients over pCRC patients. These findings suggest that the isolation of EV-based SOM-ZIF-8-DSPE is a promising strategy to identify biomarkers for disease diagnosis, such as miRNAs in plasma EVs for the early detection of CRC.

Downregulated miR-495-3p in colorectal cancer targets TGFβR1, TGFβR2, SMAD4 and BUB1 genes and induces cell cycle arrest

BACKGROUND

Hsa-miR-495 (miR-495) has been extensively investigated in cancer initiation and progression. On the other hand, our bioinformatics analysis suggested that miR-495 exerts its effects through targeting of TGFβ signaling components.

METHODS & RESULTS

In order to investigate such an effect, miR-495 precursor was overexpressed in HEK293T, SW480, and HCT116 cells, which was followed by downregulation of TGFβR1, TGFβR2, SMAD4, and BUB1 putative target genes, detected by RT-qPCR. Also, luciferase assay supported the direct interaction of miR-495 with 3'UTR sequences of TGFβR1, TGFβR2, SMAD4, and BUB1 genes. Furthermore, a negative correlation of expression between miR-495-3p and some of these target genes was deduced in a set of colorectal and breast cancer cell lines. Then, flow cytometry analysis showed that the overexpression of miR-495 in HCT116 and HEK293T resulted in an arrest at the G1 phase. Consistently, western blotting analysis showed a significant reduction of the Cyclin D1 protein in the cells overexpressing miR-495, pointing to downregulation of the TGFβ signaling pathway and cell cycle arrest. Finally, microarray data analysis showed that miR-495-3p is significantly downregulated in colorectal tumors, compared to the normal pairs.

CONCLUSIONS

Overall, the results of the current study introduced miR-495-3p as a cell cycle progression suppressor, which may negatively regulate TGFβR1, TGFβR2, SMAD4, and BUB1 genes. This finding suggests miR-495-3p as a tumor suppressor candidate for further evaluation.

miR‑151a‑5p promotes the proliferation and metastasis of colorectal carcinoma cells by targeting AGMAT

Colorectal carcinoma (CRC) is one of the most common types of digestive cancer. It has been reported that the ectopic expression of microRNAs (miRs) plays a critical role in the occurrence and progression of CRC. In addition, it has also been suggested that miR‑151a‑5p may serve as a useful biomarker for the early detection and treatment of different types of cancer and particularly CRC. However, the specific effects and underlying mechanisms of miR‑151a‑5p in CRC remain elusive. The results of the current study demonstrated that miR‑151a‑5p was upregulated in CRC cell lines and clinical tissues derived from patients with CRC. Functionally, the results showed that miR‑151a‑5p significantly promoted CRC cell proliferation, migration and invasion. Additionally, dual luciferase reporter assays verified that agmatinase (AGMAT) was a direct target of miR‑151a‑5p and it was positively associated with miR‑151a‑5p expression. Mechanistically, miR‑151a‑5p could enhance the epithelial‑mesenchymal transition of CRC cells. Taken together, the results of the current study revealed a novel molecular mechanism indicating that the miR‑151a‑5p/AGMAT axis could serve a crucial role in the regulation of CRC and could therefore be considered as a potential therapeutic strategy for CRC.

miRNAs as cornerstones in colorectal cancer pathogenesis and resistance to therapy: A spotlight on signaling pathways interplay - A review

Colorectal cancer (CRC) is the world's third most prevalent cancer and the main cause of cancer-related mortality. A lot of work has been put into improving CRC patients' clinical care, including the development of more effective methods and wide biomarkers variety for prognostic, and diagnostic purposes. MicroRNAs (miRNAs) regulate a variety of cellular processes and play a significant role in the CRC progression and spread via controlling their target gene expression by translation inhibition or mRNA degradation. Consequently, dysregulation and disruption in their function, miRNAs are linked to CRC malignant pathogenesis by controlling several cellular processes involved in the CRC. These cellular processes include increased proliferative and invasive capacity, cell cycle aberration, evasion of apoptosis, enhanced EMT, promotion of angiogenesis and metastasis, and decreased sensitivity to major treatments. The miRNAs control cellular processes in CRC via regulation of pathways such as Wnt/β-catenin signaling, PTEN/AKT/mTOR axis, KRAS, TGFb signaling, VEGFR, EGFR, and P53. Hence, the goal of this review was to review miRNA biogenesis and present an updated summary of oncogenic and tumor suppressor (TS) miRNAs and their potential implication in CRC pathogenesis and responses to chemotherapy and radiotherapy. We also summarise the biological importance and clinical applications of miRNAs in the CRC.

Comprehensive analysis of the expression, prognostic significance, and function of FAM83 family members in breast cancer

BACKGROUND

The FAM83 family plays a key role in tumorigenesis and cancer progression. However, the role of the FAM83 family in the development of breast tumors is unclear to date. This report explores the expression, prognostic significance, and function of the FAM83 family members in breast cancer using public databases.

METHODS

UALCAN database was used to explore the expression of FAM83 family members in breast cancer. Furthermore, we validated the expression of FAM83 family members in twenty pairs of breast cancer and normal tissues by RT-PCR. Kaplan-Meier plotter database was used to explore the prognostic significance of FAM83 family members in breast cancer. GeneMANIA and DAVID databases were used for functional and pathway enrichment analysis of genes co-expressed with FAM83A, FAM83D, FAM83F, and FAM83G. MEXPRESS and UALCAN databases were used to analyze the level of DNA promoter methylation of FAM83A, FAM83D, FAM83F, and FAM83G in breast cancer. TIMER database was utilized to explore the relationships between immune cell infiltration and FAM83A, FAM83D, FAM83F, and FAM83G expression.

RESULTS

Among FAM83 family members, FAM83A, FAM83D, FAM83F, and FAM83G were higher expressed in breast cancer than in normal tissues. We also validated the significant high expression of FAM83A, FAM83D, FAM83F, and FAM83G mRNA in breast cancer than in normal samples. Their increased expression has an adverse prognostic effect on breast cancer patients. These genes co-expressed with FAM83A, FAM83D, FAM83F, and FAM83G might take part in cell proliferation, G2/M transition of the mitotic cell cycle, regulation of apoptosis process and other cancer-related biological processes. In addition, they were mainly enriched in the Hippo signaling pathway, Hedgehog signaling pathway, PI3K/AKT signaling pathway, and other cancer-related pathways. We also found that promoter DNA methylation might regulate the expression of FAM83A, FAM83D, FAM83F, and FAM83G mRNA in most CpG islands. At last, we found the expression of FAM83A, FAM83D, FAM83F, and FAM83G mRNA was significantly related to immune cell infiltration.

CONCLUSIONS

FAM83A, FAM83D, FAM83F, and FAM83G were highly expressed in breast cancer tissues and had an adverse effect on the survival outcomes of breast cancer patients. Also, they were involved in breast cancer-related signal pathways. Therefore, they might serve as potential therapeutic targets for breast cancer clinical treatment.

Suppression of FAM83D Inhibits Glioma Proliferation, Invasion and Migration by Regulating the AKT/mTOR Signaling Pathway

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FAM83D is upregulated in the glioma cells and tissues.

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Silencing FAM83D inhibits the proliferation, invasion and migration of glioma cells.

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Silencing FAM83D inhibits the activity of AKT/mTOR signaling pathway.

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FAM83D inhibition limits the in vivo growth of glioma cells.

Objective

To explore the mechanism by which the family with sequence similarity 83, member D (FAM83D)-mediated AKT/mTOR signaling pathway activation affects the proliferation and metastasis of glioma cells.

Methods

FAM83D protein expression in glioma cells and tissues was detected by western blotting. Glioma U87 and U251 cells were selected and divided into the Mock, siNC, siFAM83D, FAM83D, MK2206 and FAM83D + MK2206 groups. Cell proliferation was assessed by MTT (3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide) and clone formation assays, while invasion and migration were evaluated by Transwell assays and wound healing tests. The protein expression of members of the AKT/mTOR pathway was determined via western blotting. Xenograft models were also established in nude mice to observe the in vivo effect of FAM83D on the growth of glioma.

Results

FAM83D was upregulated in glioma patients, especially in those with Stage III-IV. In addition, cells treated with siFAM83D had significant downregulation of p-AKT/AKT and p-mTOR/mTOR, with decreased proliferation and colony numbers, as well as decreased invasion and migration compared to the Mock group. However, FAM83D overexpression could activate the Akt/mTOR pathway and promote the proliferation, invasion and migration of glioma cells. Moreover, treatment with MK2206, an inhibitor of AKT, reversed the promoting effect of FAM83D on the growth of glioma cells. The in vivo experiments demonstrated that silencing FAM83D could inhibit the in vivo growth of glioma cells

Conclusion

FAM83D was upregulated in glioma and silencing FAM83D suppressed the proliferation, invasion and migration of glioma cells via inhibition of the AKT/mTOR pathway.

miRNA-142-3p functions as a potential tumor suppressor directly targeting FAM83D in the development of ovarian cancer

Background: FAM83D (family with sequence similarity 83, member D) is of particular interest in tumorigenesis and tumor progression. Ovarian cancer is the leading cause of cancer-related death in women all over the world. This study aims to research the association between FAM83D and ovarian cancer (OC).

Methods: The gene expression data of OC and normal samples (GSE81873 and GSE27651) was downloaded from Gene Expression Omnibus (GEO) dataset. The bioinformatics analysis was performed to distinguish two differentially expressed genes (DEGs), prognostic candidate genes and functional enrichment pathways. Immunohistochemistry (IHC), Quantitative Real-time PCR (qPCR), and luciferase reporter assays were utilized for further study.

Results: There were 56 DEMs and 63 DEGs in cancer tissues compared to normal tissues. According to the km-plot software, hsa-miR-142-3p and FAM83D were associated with the overall survival of patients with OC. Besides, Multivariate analysis included that hsa-miR-142-3p and FAM83D were independent risk factors for OC patients. Furthermore, qPCR demonstrated that miRNA-142-3p and FAM83D were differentially expressed in normal ovarian tissues (NOTs) and ovarian cancer tissues (OCTs). IHC results indicated that FAM83D was overexpressed in OCTs compared with NOTs. Last but not least, luciferase reporter assays verified that FAM83D was a direct target of hsa-miRNA-142-3p in OC cells.

Conclusions: The prognostic model based on the miRNA-mRNA network could provide predictive significance for the prognosis of OC patients, which would be worthy of clinical application. Our results concluded that miR-142-3p and its targets gene FAM83D may be potential diagnostic and prognostic biomarkers for patients with OC.

CircTMTC1 contributes to nasopharyngeal carcinoma progression through targeting miR-495-MET-eIF4G1 translational regulation axis

Nasopharyngeal carcinoma (NPC) is the most common primary malignancy arising from the epithelial cells of nasopharynx. CircTMTC1 is upregulated in NPC patients, but its role and molecular mechanism in NPC are unknown. Normal nasopharyngeal epithelium and tumor tissues were collected. The expression of circTMTC1, miR-495, MET/eIF4G1 pathway-related molecules were examined. Colony formation and transwell assays were used to assess cell proliferation, migration, and invasion. Cell apoptosis was analyzed by annexin V and propidium iodide (PI) staining. Gene interaction was examined by RNA immunoprecipitation (RIP) and luciferase activity assays. Subcutaneous and intravenous xenograft mouse models were established to analyze NPC growth and metastasis in vivo. CircTMTC1 was highly expressed and miR-495 was downregulated in NPC, which were associated with poor prognosis of NPC. Both circTMTC1 knockdown and miR-495 overexpression inhibited NPC cell proliferation, migration, invasion, and epithelial-mesenchymal transition (EMT) and promoted cell apoptosis. CircTMTC1 directly targeted miR-495 to promote the expression of its downstream target gene MET. miR-495 knockdown enhanced the expression of c-Myc, Cyclin D1, and survivin and accelerated NPC cell proliferation, migration, invasion, and EMT through targeting MET and activating the MET-eIF4G1 axis. CircTMTC1 silence inhibited NPC growth and lung metastasis by targeting the miR-495-MET-eIF4G1 translational regulation axis in vivo. CircTMTC1 accelerates NPC progression through targeting miR-495 and consequently activating the MET-eIF4G1 translational regulation axis, suggesting potential therapeutic targets for NPC treatment.

Induction of lncRNA NORAD accounts for hypoxia-induced chemoresistance and vasculogenic mimicry in colorectal cancer by sponging the miR-495-3p/ hypoxia-inducible factor-1α (HIF-1α)

Hypoxic microenvironment represents the hallmark of solid tumors including colorectal cancer (CRC) and facilitates angiogenesis and chemoresistance, leading to poor prognosis. lncRNA NORAD acts as an oncogenic gene to orchestrate cancer progression by regulating cell proliferation and migration. Notably, an emerging study corroborates the elevation of NORAD during hypoxic conditions in pancreatic cancer. Nevertheless, its biological role in hypoxia-evoked CRC remains unclear. Herein, enhanced expression of NORAD and hypoxia-inducible factor-1α (HIF-1α) was validated in CRC tissues. Furthermore, there was a positive association between NORAD and HIF-1α in CRC tissues. CRC cells exposed to hypoxia exhibited a stronger ability to form vasculogenic mimicry (VM) and resistance to 5-fluorouracil (5-FU), concomitant with higher expression of NORAD. NORAD knockdown restrained hypoxia-induced VM formation and VM marker VE-cadherin expression. Moreover, knockdown of NORAD counteracted CRC cell resistance to 5-FU by decreasing cell viability and increasing cell apoptosis. Additionally, NORAD loss reduced hypoxia-induced HIF-1α expression and subsequent epithelial-mesenchymal transition (EMT) by increasing E-cadherin and inhibiting N-cadherin expression. Intriguingly, HIF-1α overexpression reversed NORAD downregulation-mediated inhibition of VM formation and 5-FU resistance. There was a low expression of miR-495-3p in CRC tissues. Furthermore, NORAD could act as a competitive endogenous RNA of miR-495-3p to regulate HIF-1α. Importantly, inhibition of miR-495-3p muted the efficacy of NORAD loss in hypoxia-induced EMT, VM, and chemoresistance. Thus, the current data highlight that NORAD knockdown may antagonize hypoxia-triggered CRC malignancy by suppressing VM formation and chemoresistance by sponging miR-495-3p/HIF-1α to regulate EMT, supporting a promising therapeutic target for refractory hypoxia in CRC.

Cooperative miRNA-dependent PTEN regulation drives resistance to BTK inhibition in B-cell lymphoid malignancies

Aberrant microRNA (miR) expression plays an important role in pathogenesis of different types of cancers, including B-cell lymphoid malignancies and in the development of chemo-sensitivity or -resistance in chronic lymphocytic leukemia (CLL) as well as diffuse large B-cell lymphoma (DLBCL). Ibrutinib is a first-in class, oral, covalent Bruton's tyrosine kinase (BTK) inhibitor (BTKi) that has shown impressive clinical activity, yet many ibrutinib-treated patients relapse or develop resistance over time. We have reported that acquired resistance to ibrutinib is associated with downregulation of tumor suppressor protein PTEN and activation of the PI3K/AKT pathway. Yet how PTEN mediates chemoresistance in B-cell malignancies is not clear. We now show that the BTKi ibrutinib and a second-generation compound, acalabrutinib downregulate miRNAs located in the 14q32 miRNA cluster region, including miR-494, miR-495, and miR-543. BTKi-resistant CLL and DLBCL cells had striking overexpression of miR-494, miR-495, miR-543, and reduced PTEN expression, indicating further regulation of the PI3K/AKT/mTOR pathway in acquired BTKi resistance. Additionally, unlike ibrutinib-sensitive CLL patient samples, those with resistance to ibrutinib treatment, demonstrated upregulation of 14q32 cluster miRNAs, including miR-494, miR-495, and miR-543 and decreased pten mRNA expression. Luciferase reporter gene assay showed that miR-494 directly targeted and suppressed PTEN expression by recognizing two conserved binding sites in the PTEN 3'-UTR, and subsequently activated AKT^Ser473. Importantly, overexpression of a miR-494 mimic abrogated both PTEN mRNA and protein levels, further indicating regulation of apoptosis by PTEN/AKT/mTOR. Conversely, overexpression of a miR-494 inhibitor in BTKi-resistant cells restored PTEN mRNA and protein levels, thereby sensitizing cells to BTKi-induced apoptosis. Inhibition of miR-494 and miR-495 sensitized cells by cooperative targeting of pten, with additional miRNAs in the 14q32 cluster that target pten able to contribute to its regulation. Therefore, targeting 14q32 cluster miRNAs may have therapeutic value in acquired BTK-resistant patients via regulation of the PTEN/AKT/mTOR signaling axis.

MicroRNA miR-495 regulates the development of Hepatocellular Carcinoma by targeting C1q/tumor necrosis factor-related protein-3 (CTRP3)

Hepatocellular carcinoma (HCC) represents a type of lethal cancer in the world and its treatment options produce limited and unsatisfactory effectiveness. MicroRNAs (miRNAs) that play critical roles in tumorigenesis have shown promising clinical therapeutic potential. Here, we reported that miRNA-495 (miR-495) plays important roles in inhibiting HCC cell growth via its regulation of cell-cycle progression as well as senescence. MiR-495 showed low levels in human HCC tissues and cells. Overexpressing miR-495 in HCC cells caused strong cell growth inhibition, which results from cell-cycle arrest and senescence. CTRP3 functioned as a possible target of miR-495 in HCC cells by bioinformatics prediction and biological assay. By inhibiting the expression of CTRP3 with siRNA, HCC cells also showed similar growth inhibition as miR-495 overexpression. The re-expression of CTRP3 in HCC cells with high-level miR-495 abolished miR-495 and caused cell growth inhibition. These results strongly suggested that CTRP3 was the functional target that weakened the effects of miR-495 in HCC cells. The in vivo experiment demonstrated miR-495 overexpression had great therapeutic effects on HCC in xenograft. Above all, this research revealed that miR-495 is essential in suppressing HCC growth, and its application serves as a promising strategy for HCC treatment.

lncRNA UCA1 induced by SP1 and SP3 forms a positive feedback loop to facilitate malignant phenotypes of colorectal cancer via targeting miR-495

AIMS

Long noncoding RNA (LncRNA) urothelial cancer associated 1 (UCA1) was dysregulated in colorectal cancers (CRC) and promoted tumor progression of CRC. The aims of this study are to further investigate the underlying mechanism.

MAIN METHODS

Short hairpin RNAs (shRNAs) were applied for gene knockdown. microRNA mimic and pcDNA-UCA1 plasmids were transfected for miR-495 and UCA1 overexpression, respectively. MTT was applied to determine cell viability and sensitivity of 5-fluorouracil (FU). Transwell assays were performed to evaluate cell migration/invasion. Angiogenesis was evaluated by tube formation. Western blotting and quantitative PCR were utilized for protein and mRNA detection, respectively. The interaction of UCA1, miR-495 and SP1/SP3 were explored by dual-luciferase assay. RNA pulldown was adopted to determine the UCA1/miR-495 interaction.

KEY FINDINGS

UCA1 was significantly upregulated in CRC tissues. UCA1 enhanced cell proliferation, migration/invasion, angiogenesis, epithelial-mesenchymal transition, and resistance to 5-FU in CRC cell lines. MiR-495 was inversely correlated to the expression of UCA1. The results indicated that UCA1 sponged miR-495, leading to the disinhibition of SP1/SP3 expression. SP1/SP3 induced the expression of DNA methyltransferases and, in turn, contributed to UCA1 mediated tumor-promoting actions. Reduction of SP1/SP3 exerted anti-cancer effects, which can be reversed by forced expression of UCA1.

SIGNIFICANCE

UCA1-miR-495-SP1/SP3 axis is dysregulated in CRC and contributed to malignant phenotypes of CRC. UCA1-SP1/SP3 may form a positive feedback loop in CRC.

Identification of MYLIP gene and miRNA-802 involved in the growth and metastasis of cervical cancer cells

BACKGROUND

The dysregulation of microRNA-802 (miR-802) has crucial roles in cancer progression. Nevertheless, the bio-function of miR-802 in cervical cancer remains unclear.

OBJECTIVE

Hence, we illuminated the potential roles of miR-802 in cervical cancer cell growth, migration, and invasion.

METHODS

The levels of miR-802 and myosin regulatory light chain interacting protein (MYLIP) were measured using qRT-PCR assay. The potential effects of miRNA-802 on cervical cancer cell proliferation and metastatic phenotypes were determined using CCK-8, colony formation, wound healing and Transwell invasion assays. MYLIP was validated as a downstream target gene of miRNA-802 using bioinformatics analysis tool and luciferase report gene assay. The impact of miR-802 on the growth of cervical cancer cell in vivo was analyzed using xenograft model. The expression of MYLIP was measured by western blotting and immunohistochemistry (IHC).

RESULTS

MiRNA-802 was distinctly down-regulated in cervical cancer cells as well as clinical cervical cancer samples. Upregulation of miRNA-802 significantly inhibited the growth and aggressiveness of cervical cancer cell. Additional, MYLIP was a functional target of miR-802. MYLIP was ovrerexpressed in cervical cancer and MYLIP level was negatively associated with the level of miR-802. Overexpression of MYLIP eliminated the inhibitory effects of miR-802 on growth and metastatic-related traits of cervical cancer cell. In vivo, miR-802 also markedly reduced the tumor growth of cervical cancer cell and decreased the expression of MYLIP.

CONCLUSIONS

MiR-802 inhibits the growth and metastatic-related phenotypes of cervical cancer cell through targeting MYLIP.

An epithelial-mesenchymal transition-related 5-gene signature predicting the prognosis of hepatocellular carcinoma patients

Background

Tumor metastasis is one of the leading reasons of the dismal prognosis of hepatocellular carcinoma (HCC). Epithelial-mesenchymal transition (EMT) is closely associated with tumor metastasis including HCC. The purpose of this study is to construct and validate an EMT-related gene signature for predicting the prognosis of HCC patients.

Methods

Gene expression data of HCC patients was downloaded from The Cancer Genome Atlas (TCGA) database. Gene set enrichment analysis (GSEA) was performed to found the EMT-related gene sets which were obviously distinct between normal samples and paired HCC samples. Cox regression analysis was used to develop an EMT-related prognostic signature, and the performance of the signature was evaluated by Kaplan–Meier curves and time-dependent receiver operating characteristic (ROC) curves. A nomogram incorporating the independent predictors was established. Quantitative real-time polymerase chain reaction (qRT-PCR) was used to detect the expression levels of the hub genes in HCC cell lines, and the role of PDCD6 in the metastasis of HCC was determined by functional experiments.

Results

An EMT-related 5-gene signature (PDCD6, TCOF1, TRIM28, EZH2 and FAM83D) was constructed using univariate and multivariate Cox regression analysis. Based on the signature, the HCC patients were classified into high- and low-risk groups, and patients in high-risk group had a poor prognosis. Time-dependent ROC and Cox regression analyses suggested that the signature could predict HCC prognosis exactly and independently. The predictive capacity of the signature was also validated in two external cohorts. GSEA results showed that many cancer-related signaling pathways such as PI3K/Akt/mTOR pathway and TGF-β/SMAD pathway were enriched in high-risk group. The result of qRT-PCR revealed that PDCD6, TCOF1 and FAM83D were highly expressed in HCC cancer cells. Among them, PDCD6 were found to promote cell migration and invasion.

Conclusion

The EMT-related 5-gene signature can serve as a promising prognostic biomarker for HCC patients and may provide a novel mechanism of HCC metastasis.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12935-021-01864-5.

Biological Implications and Clinical Potential of Metastasis-Related miRNA in Colorectal Cancer

Colorectal cancer (CRC), ranking as the third commonest cancer, leads to extremely high rates of mortality. Metastasis is the major cause of poor outcome in CRC. When metastasis occurs, 5-year survival rates of patients decrease sharply, and strategies to enhance a patient's lifetime seem limited. MicroRNAs (miRNAs) are evolutionarily conserved small non-coding RNAs that are significantly involved in manipulation of CRC malignant phenotypes, including proliferation, invasion, and metastasis. To date, accumulating studies have revealed the mechanisms and functions of certain miRNAs in CRC metastasis. However, there is no systematic discussion about the biological implications and clinical potential (diagnostic role, prognostic role, and targeted therapy potential) of metastasis-related miRNAs in CRC. This review mainly summarizes the recent advances of miRNA-mediated metastasis in CRC. We also discuss the clinical values of metastasis-related miRNAs as potential biomarkers or therapeutic targets in CRC. Moreover, we envisage the future orientation and challenges in translating these findings into clinical applications.

Circular RNA circ_0000372 contributes to the proliferation, migration and invasion of colorectal cancer by elevating IL6 expression via sponging miR-495

Circular RNAs are thought to play a vital function in the progression of various cancers, including colorectal cancer (CRC). However, the biological function and mechanism of circ_0000372 in CRC are still not clear. The expression of circ_0000372 and microRNA (miR)-495 was examined by quantitative real-time PCR. Cell proliferation was evaluated using cell counting kit 8 and colony formation assays. Further, cell migration and invasion were assessed using transwell assay. Additionally, western blot analysis was used to detect the expression of proteins associated with proliferation, metastasis, Janus kinase 2 (JAK2)/signal transducers and activators of transcription (STAT3) signaling pathway and interleukin 6 (IL6). Dual-luciferase reporter assay and RNA immunoprecipitation assay were employed to verify the interaction between miR-495 and circ_0000372 or IL6. Furthermore, the effect of circ_0000372 on CRC tumor growth in vivo was explored using the mice xenograft models. Circ_0000372 was markedly upregulated in CRC, and its high expression was associated with the poor prognosis of CRC patients. Silenced circ_0000372 was able to suppress CRC cell proliferation, migration and invasion in vitro and CRC tumor growth in vivo. Bioinformatics prediction and experimental verification proposed that circ_0000372 could sponge miR-495, and miR-495 could target IL6. Besides, the JAK2/STAT3 signaling pathway activation could be regulated by circ_0000372, miR-495 and IL6. Rescue assay results confirmed that the inhibition effect of circ_0000372 knockdown on the proliferation and metastasis of CRC could be reversed by miR-495 inhibitor or IL6 overexpression. In short, we concluded that circ_0000372 promoted CRC progression by regulating the miR-495/IL6 axis, suggesting that circ_0000372 could be used as a new prognostic biomarker and therapeutic target for CRC.

Dissecting miRNA signature in colorectal cancer progression and metastasis

Colorectal cancer (CRC) is the third most common cancer and leading cause of cancer related deaths worldwide. Despite recent advancements in surgical and molecular targeted therapies that improved the therapeutic efficacy in CRC, the 5 years survival rate of CRC patients still remains frustratingly poor. Accumulated evidences indicate that microRNAs (miRNAs) play a crucial role in the progression and metastasis of CRC. Dysregulated miRNAs are closely associated with cancerous phenotypes (e.g. enhanced proliferative and invasive ability, evasion of apoptosis, cell cycle aberration, and promotion of angiogenesis) by regulating their target genes. In this review, we provide an updated overview of tumor suppressive and oncogenic miRNAs, circulatory miRNAs, and the possible causes of dysregulated miRNAs in CRC. In addition, we discuss the important functions of miRNAs in drug resistance of CRC.

Correlation between lncRNA SNHG16 gene polymorphism and its interaction with environmental factors and susceptibility to colorectal cancer

OBJECTIVE

To study the relationship between long-chain non-coding RNA small nucleolar RNA host gene 16 (lncRNA SNHG16) polymorphisms and its interaction with environmental factors and susceptibility to colorectal cancer (CRC).

METHODS

Sanger sequencing was used to analyze genotypes of lncRNA SNHG16 gene rs7353, rs8038, and rs15278 sites. Multifactor dimensionality reduction was used to analyze interactions between lncRNA SNHG16 gene rs7353, rs8038, rs15278 sites, and environmental factors. Haploview 4.1 software was used to analyze linkage disequilibrium of lncRNA SNHG16 gene rs7353, rs8038, and rs15278 sites. Quantitative real-time polymerase chain reaction was used to analyze plasma lncRNA SNHG16 levels of CRC patients and control subjects.

RESULTS

Variation of the lncRNA SNHG16 gene rs7353 site A>G variation was associated with decreased CRC susceptibility (Odds ratio [OR] = 0.50, 95% confidence interval [CI]: 0.40-0.62, P < .01). The rs8038 site G>A and rs15278 site A>G variation were associated with increased CRC susceptibility (OR = 1.87, 95% CI: 1.47-2.36, P < .01). The rs15278 site G>A variation was associated with increased CRC susceptibility (OR = 2.24, 95% CI: 1.61-3.11, P < .01). Interaction combinations featuring age, rs7353, rs8038, and rs15278 single nucleotide polymorphism are 13.53 times more susceptible to CRC than other interactions (95% CI: 9.43-19.41, P < .01). The rs15278, rs8038, and rs7353 site AGA haplotypes were significantly associated with a decreased CRC risk (OR = 0.65, 95% CI: 0.48-0.88, P = .01), AAG haplotypes were significantly associated with an increased CRC risk (OR = 2.00, 95% CI: 1.27-3.17, P < .01). High lncRNA SNHG16 expression was associated with tumor progression in CRC patients (χ = 8.85, P = .03). The rs7353 site A>G variation caused a significant decrease in plasma lncRNA SNHG16 level (P < .01), while the rs8038 site G>A variation and rs15278 site A>G variation resulted in increased plasma lncRNA SNHG16 levels.

CONCLUSION

Polymorphisms of lncRNA SNHG16 gene rs7353, rs8038, rs15278 loci and their interaction with age are significantly associated with CRC susceptibility.

Long non‑coding RNA SNHG20 promotes colorectal cancer cell proliferation, migration and invasion via miR‑495/STAT3 axis

Colorectal cancer (CRC) is one of the primary causes of cancer-associated mortality worldwide. However, the potential molecular mechanism of CRC progression remains unknown. Long non-coding RNA small nucleolar RNA host gene 20 (SNHG20) has been demonstrated to be involved in the development and progression of a variety of tumors, including CRC. However, the involvement of SNHG20 in CRC progression remains unclear. The aim of the present study was to investigate the functional role and molecular mechanism of SNHG20 in CRC progression. In the present study, SNHG20 expression was found to be significantly upregulated in CRC tissues and cell lines. Association analysis indicated that high SNHG20 expression was significantly association with greater tumor size (P=0.014), tumor invasion depth (P=0.019), positive lymph node status (P=0.022), distant metastasis (P=0.017) and advanced tumor node metastasis stage (P=0.038). Loss-of-function experiments indicated that SNHG20 knockdown could significantly suppress proliferation, migration and invasion in vitro. Notably, SNHG20 knockdown significantly inhibited tumor growth and lung metastasis in vivo. Bioinformatics analysis and luciferase reporter assays confirmed that microRNA (miR)-495 was a direct target of SNHG20. Rescue assays indicated that miR-495 inhibitor reversed the suppressive effects of SNHG20 knockdown on CRC progression. Moreover, STAT3 was identified as a downstream target of miR-495 in CRC. STAT3 overexpression partially rescued the inhibitory effects of SNHG20 knockdown on CRC progression. Taken together, the results revealed that SNHG20 facilitated CRC progression by regulating STAT3 expression and by sponging miR-495.

LINC01106 drives colorectal cancer growth and stemness through a positive feedback loop to regulate the Gli family factors

Long non-coding RNAs (lncRNAs) are essential contributors to the progression of various human cancers. Long intergenic non-protein coding RNA 1106 is a member of lncRNAs family. Until now, the specific role of LINC01106 in CRC remains undefined. The aim the current study was to unveil the functions of LINC01106 and explore its potential molecular mechanism in CRC. Based on the data of online database GEPIA, we determined that LINC01106 was expressed at a high level in colon adenocarcinoma (COAD) tissues compared to normal colon tissues. More importantly, high level of LINC01106 had negative correlation with the overall survival of COAD patients. Additionally, we also determined the low level of LINC01106 in normal colon tissues based on UCSC database. Through qRT-PCR, we identified that LINC01106 was highly expressed in CRC tissues compared to adjacent normal ones. Similarly, we detected the expression of LINC01106 and confirmed that LINC01106 was expressed higher in CRC cells than that in normal cells. Subsequently, LINC01106 was mainly distributed in the cytoplasm. LINC01106 induced the proliferation, migration, and stem-like phenotype of CRC cells. Mechanistically, cytoplasmic LINC01106 positively modulated Gli4 in CRC cells by serving as a miR-449b-5p sponge. Furthermore, nuclear LINC01106 could activate the transcription of Gli1 and Gli2 through recruiting FUS to Gli1 and Gli2 promoters. Mechanism of investigation unveiled that Gli2 was a transcription activator of LINC01106. In conclusion, Gli2-induced upregulation of LINC01106 aggravates CRC progression through upregulating Gli2, Gli2, and Gli4.

MicroRNA-126 exerts antitumor functions in ovarian cancer by targeting EGFL7 and affecting epithelial-to-mesenchymal transition and ERK/MAPK signaling pathway

Ovarian cancer (OC) is a common gynecological malignant carcinoma worldwide. Accumulating research has revealed that multiple microRNAs (miRNAs) are abnormally expressed at different levels in various malignancies, playing vital roles in tumorigenesis. This study investigated the regulatory functions and potential mechanism of miR-126 in OC proliferation, invasion and migration. It was found that miR-126 was prominently downregulated in OC. Moreover, the decrease of miR-126 promoted the aggressive phenotypes and indicated poor prognosis of OC patients. Functional assays demonstrated that restoration of miR-126 dramatically repressed OC cell proliferation, migration and invasion. Furthermore, luciferase reporter assay was conducted to verify putative binding sites of miR-126 in the epidermal growth factor-like domain 7 (EGFL7) 3 untranslated region (3'UTR), indicating that EGFL7 was a target gene of miR-126 in OC cells. It was further discovered that miR-126 exerts its function on regulating ERK/MAPK pathway and epithelial-to-mesenchymal transition (EMT) in OC cells. The above findings suggested that miR-126 served as a cancer suppressor in OC, suggesting a promising application of miR-126 in the clinical diagnosis and therapeutics of OC.

Long non-coding RNA FENDRR restrains the aggressiveness of CRC via regulating miR-18a-5p/ING4 axis

There is increasing evidence has indicated that long non-coding RNAs (lncRNAs) are implicated in the tumorigenesis and development of colorectal cancer (CRC). Nevertheless, the clinical significances and functions of FENDRR in CRC remain unknown. In this study, we reveal that lncRNA FENDRR is downregulated in CRC and negatively correlated with advanced stage and poor clinical outcomes of patient with CRC. Overexpression of FENDRR represses the proliferation, migrate and invasive capacities of CRC cell in vitro, and upregulation of FENDRR inhibits the growth and distant metastatic capacity of CRC cell in vivo. Mechanistically, FENDRR interacts with miRNA-18a-5p (miR-18a-5p) and subsequently regulates the expression of inhibitor of growth 4 (ING4) in CRC cell. Interestingly, ING4 repression or miR-18a-5p rescues FENDRR induced proliferation and aggressive phenotypes inhibition of CRC cell. Altogether, our findings suggest that FENDRR exerts an inhibitory role in CRC by interacting with miR-18a-5p and future increases ING4 expression.

FAM83D promotes epithelial-mesenchymal transition, invasion and cisplatin resistance through regulating the AKT/mTOR pathway in non-small-cell lung cancer

PURPOSE

FAM83D has been proposed to act as an oncoprotein in several types of human cancer. Its role and mode of action in human non-small cell lung cancer (NSCLC) metastasis and its impact on chemotherapy are as yet, however, poorly understood.

METHODS

FAM83D expression was measured in NSCLC cells and normal lung epithelial cells, as well as in primary NSCLC tissues and corresponding adjacent non-cancerous tissues, using qRT-PCR, Western blotting and immunohistochemistry. FAM83D was stably overexpressed in BEAS2B cells or silenced in A549 and H1299 cells using retroviral or lentiviral vectors. The growth capacity of NSCLC cells was evaluated using MTT and colony formation assays. Epithelial-mesenchymal transition (EMT) was assessed using Western blotting and immunofluorescence. NSCLC cell invasive capacities were assessed using scratch wound healing and Boyden chamber assays. NSCLC cell viability in response to cisplatin treatment was assessed using MTT assays in vitro and a xenograft model in vivo.

RESULTS

We found that FAM83D expression levels were significantly elevated in NSCLC cells and tissues, and positively correlated with tumor progression and a poor prognosis. Exogenous FAM83D overexpression promoted, while FAM83D silencing inhibited NSCLC cell proliferation, EMT and invasion. FAM83D silencing also reduced cisplatin resistance. Concordantly, we found that NSCLC patients with a low FAM83D expression benefited most from chemotherapy. Mechanistically, we found that FAM83D activated the protein kinase B (AKT)/mammalian target of rapamycin (mTOR) pathway. Pharmacological treatment with either AKT or mTOR inhibitors reverted FAM83D-induced tumorigenic phenotypes.

CONCLUSIONS

Our results suggest a role of FAM83D in NSCLC development. In addition, our results indicate that NSCLC patients exhibiting FAM83D overexpression are likely to benefit from AKT and/or mTOR inhibitor treatment.

circFOXM1 promotes proliferation of non-small cell lung carcinoma cells by acting as a ceRNA to upregulate FAM83D

Background

Biological role and clinical significance of circular RNAs (circRNAs) remain largely unknown. Herein, we aimed to investigate biological function, molecular mechanism, and clinical significance of a circular RNA FOXM1 (circFOXM1) in non-small cell lung cancer (NSCLC).

Methods

Expression of circFOXM1 was measured in 48 paired samples of NSCLC by qRT-PCR. Functional roles of circFOXM1 on tumor cells were explored by in vitro and in vivo assays. Transcriptome sequencing was employed to screen the molecules involved in circFOXM1 regulatory network. RNA immunoprecipitation, luciferase analysis, RNA pull-down, and rescue assay were used to investigate potential mechanisms of circFOXM1.

Results

We found that circFOXM1 was significantly upregulated in NSCLC tissues, and its upregulation was positively correlated with advanced clinical stage and poor prognosis of NSCLC patients. Gain or loss-of-function assay showed that circFOXM1 promoted cell proliferation and cell cycle progression. In vivo assays showed that silencing circFOXM1 inhibited xenograft tumor growth. Mechanically, transcriptome sequencing data indicated that silencing circFOXM1 led to the downregulation of cell cycle-related mRNAs. RNA pull-down and dual-luciferase reporter assay suggested that circFOXM1 could bind to miR-614, and FAM83D was an essential gene involved in the circFOXM1/miR-614 regulatory network.

Conclusions

circFOXM1promotes NSCLC progression by interacting with miR-614 and thus inactivating the function of miR-614, which will further release the suppression of FAM83D. circFOXM1/miR-614/FAM83D regulatory network may serve as a potential therapeutic target for NSCLC patients.

Genome-wide analysis to identify a novel microRNA signature that predicts survival in patients with stomach adenocarcinoma

Objective: Using genome-wide screening, this study was aimed at identifying prognostic microRNA (miRNA) in those patients suffering from stomach adenocarcinoma (STAD).

Methods: A genome-wide miRNA sequencing dataset and relevant STAD clinical information was obtained via The Cancer Genome Atlas (TCGA). Prognostic miRNA selection was carried out through a whole genome multivariate Cox regression model in order to establish a prognostic STAD signature.

Results: Eleven miRNAs (hsa-mir-509-2, hsa-mir-3917, hsa-mir-495, hsa-mir-653, hsa-mir-3605, hsa-mir-2115, hsa-mir-1292, hsa-mir-137, hsa-mir-6511b-1, hsa-mir-145, and hsa-mir-138-2) were recognized as prognostic and used for the construction of a STAD prognostic signature. This signature exhibited good performance in predicting prognosis (adjusted P<0.0001, adjusted hazard ratio= 3.047, and 95% confidence interval=2.148-4.323). The time-dependent receiver operating characteristic examination exhibited area under curve values of 0.711, 0.697, 0.716, 0.733, 0.805, and 0.805, for 1-, 2-, 3-, 4-, 5-, and 10-year overall survival (OS) estimation, respectively. Comprehensive survival analysis suggests that the 11-miRNA prognostic signature acts as an independent feature of STAD prognosis and exhibits superior performance in OS prediction when compared to traditional clinical parameters. Furthermore, fourteen miRNA target genes were linked to STAD OS. These included SERPINE1, MLEC, ANGPT2, C5orf38, FZD7, MARCKS, PDGFD, DUSP6, IRS1, PSAT1, TENM3, TMEM127, BLMH, and TIRAP. Functional and gene set enrichment analysis suggested that target genes and the 11-miRNA prognostic signature were both participate in various biological processes and pathways, including the growth factor beta, Wnt, and Notch signaling pathways.

Conclusions: By means of a genome-wide analysis, an 11-miRNA expression signature that may serve as an underlying prognostic indicator for those patients suffering from STAD has been identified and described here.

LINC00491 as a new molecular marker can promote the proliferation, migration and invasion of colon adenocarcinoma cells

Background

Long non-coding RNAs (lncRNAs) play an important role in the pathogenesis of multiple tumors. However, the roles of lncRNAs during colon adenocarcinoma and cancer progression remain unclear. This study aimed identify new lncRNAs that act as molecular markers for the prevention and diagnosis of colon adenocarcinoma.

Methods

RNA sequencing (RNA-Seq) data associated with colon adenocarcinoma were retrieved from the Cancer Genome Atlas (TCGA). Biological processes in Gene Ontology (Go) and the Kyoto Encyclopedia of Genomes (KEGG) were searched for pathways at the significance level. The expression of LINC00491 and its downstream targets were assessed by real-time PCR, Western blotting and dual-luciferase assays. Biological functions of LINC00491 during cell proliferation, migration and invasion were assessed using CCK-8, colony formation assays, wound healing, and transwell invasion assays in colon adenocarcinoma HT-29 and HCT116 cells.

Results

Bioinformatics analysis with the TCGA colon adenocarcinoma dataset showed that LINC00491 was significantly up-regulated in colon adenocarcinoma. Furthermore, we found that LINC00491 positively regulates SERPINE1 expression through sponging miR-145 and promoting the proliferation, migration, and invasion of colon adenocarcinoma cells, thus playing an oncogenic role during colon adenocarcinoma pathogenesis.

Conclusion

LINC00491 functions as a ceRNA to promote SERPINE1 expression by sponging miR-145. LINC00491 serves as a therapeutic target and prognostic biomarker in colon adenocarcinoma.

miR-148a inhibits cell proliferation and migration through targeting ErbB3 in colorectal cancer

Colorectal cancer is a common gastrointestinal cancer ranking in third place of all cancers. Downregulation of miR-148a has been observed in many tumors, and miR-148a was found to be an oncogene in colorectal cancer. The aim of our study was to investigate the molecular mechanisms by which miR-148a and ErbB3 proliferate and migrate in colorectal cancer. The expression of miR-148a and ErbB3 were measured by western blot analysis and RT-qPCR. MTT and transwell assays were performed to analyze the proliferative and migratory abilities. The dual luciferase reporter assay was employed to confirm miR-148a regulated the expression of ErbB3 in colorectal cancer. It was discovered that miR-148a was overexpressed while ErbB3 expression was low in colorectal cancer, and the mRNA level of miR-148a had a negative correlation with the expression of ErbB3. Upregulation of miR-148a suppressed the proliferation and migration in colorectal cancer cells. Furthermore, ErbB3 was identified as a direct target of miR-148a, which suppressed the proliferation and migration through directly binding to the 3′UTR of ErbB3 mRNA. This study established that miR-148a inhibited the proliferative and migratory abilities through mediating the expression of ErbB3. The newly identified miR-148a/ErbB3 axis provides novel insight into the pathogenesis of colorectal cancer, and represents a potential target for treatment of colorectal cancer.

miR-496, miR-1185, miR-654, miR-3183 and miR-495 are downregulated in colorectal cancer cells and have putative roles in the mTOR pathway

MicroRNAs (miRNAs) are small non-coding RNAs that regulate gene expression by suppressing the target mRNA and inhibiting translation in order to regulate multiple biological processes. miRNAs play important roles as oncogenes or tumor suppressors in the development of various types of human cancer. The regulation of mammalian target of rapamycin (mTOR) by miRNAs has been studied in several types of cancer, including colorectal cancer (CRC). However, to the best of our knowledge, only limited information regarding the function of miRNAs in human CRC is available. In the present study, the expression of 22 miRNAs in CRC cell lines were investigated in regard to key genes in the mTOR pathway. Initially, it was revealed that mTOR, regulatory-associated protein of mTOR complex I and rapamycin-intensive companion of mTOR were overexpressed in CRC cell lines when compared with a normal colorectal cell line. Subsequently, putative miRNA-mRNA associations were identified via multiple miRNA target prediction programs. The expression levels for the candidate miRNAs were validated using quantitative real-time polymerase chain reaction. Expression analysis revealed that, among 20 miRNAs, five miRNAs (miR-496, miR-1185, miR-654, miR-3183 and miR-495) exhibited significant downregulation in association with the mTOR signaling pathway. Taken together, the results from the present study suggest that several miRNAs that are associated with CRC, with possible roles in mTOR signaling, may have potential therapeutic or diagnostic benefits in CRC treatment.

Overexpression of microRNA-216a inhibits autophagy by targeting regulated MAP1S in colorectal cancer

Background: Autophagy executes the rapid degradation of unneeded proteins and organelles through the lysosomal pathway, and is a crucial catabolic process widely conserved among eukaryotes. miRNAs can modulate autophagy by targeting genes encoding proteins involved in the process. A great deal of researchhas indicated that miR-216a was a functional miRNA related to tumorigenesis. However, the contribution of miR-216a to autophagy in colorectal cancer (CRC) remains unclear. The purpose of this study was to investigate the role of miR-216a in autophagy in CRC cells. Methods: The expression levels of miR-216a in 67 paired CRC patients were evaluated by qRT-PCR. Direct gene targeting predicted by TargetScan and miRanda was confirmed by luciferase activity. Western blot and flow cytometry were used to identify the regulatory mechanism of miR-216a on autophagy in CRC cells. Results: We determined that miR-216a is downregulated in CRC by screening its expression in 67 CRC tissue samples. Dual luciferase reporter assays showed that miR-216a binds the 3'-UTR of MAP1S, suggesting that MAP1S is a direct target of miR-216a. miR-216a could inhibit autophagy in HCT-116 and HT-29 CRC cells through downregulating MAP1S expression. Flow cytometry and Western blot analysis demonstrated that overexpression of miR-216a reduced MAP1S mRNA and protein levels. Moreover, we determined that miR-216a-regulated inhibition of autophagy via MAP1S regulation involves the TGF-β pathway. Conclusion: Taken together, our findings indicate that miR-216a was a tumor-suppressor miRNA in human CRC, which can inhibit autophagy via the TGF-β/MAP1S pathway.

lncRNA NEAT1 facilitates melanoma cell proliferation, migration, and invasion via regulating miR-495-3p and E2F3

Melanoma contributes a lot to skin cancer-related deaths. lncRNAs are implicated in various diseases, including melanoma. lncRNA NEAT1 is frequently dysregulated and can play important roles in multiple cancers. Nevertheless, little has been studied about the function of NEAT1 in melanoma progression. In our present research, we displayed NEAT1 was overexpressed in melanoma cells. A series of functional assays showed that overexpression of NEAT1 promoted the proliferation, migration, and invasion of melanoma cells. By contrast, NEAT1 knockdown obviously restrained melanoma cell progression. Mechanistically, it was revealed that NEAT1 could directly bind with miR-495-3p, which led to a negative effect on miR-495-3p levels. In addition, miR-495-3p was significantly decreased in melanoma cells. Furthermore, E2F3 was postulated as the target of miR-495-3p and overexpression of this miR could suppress the levels of E2F3. Meanwhile, it was exhibited that melanoma cell proliferation, migration, and invasion induced by E2F3 silence was abrogated by miR-495-3p. Moreover, an in vivo xenograft nude mice model was established using A375 cells and it was indicated that NEAT1 promoted melanoma progression in vivo via regulating the miR-495-3p/E2F3 axis. In conclusion, we suggest that NEAT1 exerts an oncogenic effect on melanoma development via inhibition of miR-495-3p and induction of E2F3. NEAT1 might serve as a crucial prognostic biomarker of melanoma.

FAM83D inhibits autophagy and promotes proliferation and invasion of ovarian cancer cells via PI3K/AKT/mTOR pathway

Ovarian cancer is one of the most lethal malignant tumors in women. The family with sequence similarity 83, member D (FAM83D) plays an important role in several cancers, but its function and underlying mechanism in ovarian cancer remain unknown. To investigate the role of FAM83D in ovarian cancer, the expression of FAM83D was determined by immunohistochemistry in tissue microarray slide. Cellular proliferation and invasion were detected by 5-Ethynyl-2'-deoxyuridine assays and transwell invasion assays. The correlations between FAM83D and autophagy were detected by western blot analysis and confocal microscopy. Western blot analysis was used to identify the protein expression of FAM83D, phosphoinositide 3-kinase (PI3K), protein kinase B (AKT), mammalian target of rapamycin (mTOR) and Sequestosome 1 (P62). Tumorigenesis in nude mice was used to explore the function of FAM83D in vivo. We found high expression level of FAM83D in ovarian cancer tissues as compared to the normal ovarian tissues. Knockdown of FAM83D in SKOV3 cells enhanced autophagy and inhibited the proliferation and invasion in vitro, whereas ectopic expression of FAM83D in A2780 cells exerted an opposite effect. Mechanistically, overexpression of FAM83D activated the PI3K/AKT/mTOR pathway, and Torin1 could suppress FAM83D-induced cell proliferation and invasion. In vivo, overexpression FAM83D promoted tumor growth. Overall, FAM83D promoted ovarian cancer cell invasion and proliferation, while inhibited autophagy via the PI3K/AKT/mTOR signaling pathway. Our results suggest that FAM83D may be a candidate oncogene in ovarian cancer, which provides a fresh perspective of FAM83D in ovarian cancer.

Genetic associations between the miRNA polymorphisms miR-130b (rs373001), miR-200b (rs7549819), and miR-495 (rs2281611) and colorectal cancer susceptibility

BACKGROUND

Recent studies have extensively investigated the role of miRNAs in colorectal cancer (CRC), and several associations have been reported. In addition, single nucleotide polymorphisms (SNPs) in promoter regions of miRNAs have been shown to affect miRNA expression. Therefore, we aimed to analyze the effect of miRNA polymorphisms on CRC susceptibility.

METHODS

We conducted association studies on the relationships between the miRNA polymorphisms miR-130bT > C rs373001, miR-200bT > C rs7549819, and miR-495A > C rs2281611 and CRC with 472 CRC patients and 399 control subjects in Korea.

RESULTS

Multivariate logistic regressions of the CRC subgroups showed that the miR-495CC genotype associated with rectal cancer (AA+AC vs. CC; adjusted odds ratio (AOR) for CC, 1.592; 95% confidence interval (CI), 1.071-2.368; P = 0.022). The gene-environment combinatorial analysis showed that the combination of miR-495A > C and low plasma folate contributed to an increased risk of rectal cancer (AA+AC vs. CC; AOR for CC, 3.829; 95% CI, 1.577-9.300; P = 0.003). In the survival analysis, miR-200bT > C associated with CRC patient mortality (TT vs TC + CC; adjusted hazard ratio for TC + CC, 0.592; 95% CI, 0.373-0.940; P = 0.026).

CONCLUSION

In this study, we found that miR-200b and miR-495 polymorphisms are involved in CRC susceptibility and prognosis.

Enhanced Inhibition of Tumorigenesis Using Combinations of miRNA-Targeted Therapeutics

The search for effective strategies to inhibit tumorigenesis remains one of the most relevant scientific challenges. Among the most promising approaches is the direct modulation of the function of short non-coding RNAs, particularly miRNAs. These molecules are propitious targets for anticancer therapy, since they perform key regulatory roles in a variety of signaling cascades related to cell proliferation, apoptosis, migration, and invasion. The development of pathological states is often associated with deregulation of miRNA expression. The present review describes in detail the strategies aimed at modulating miRNA activity that invoke antisense oligonucleotide construction, such as small RNA zippers, miRNases (miRNA-targeted artificial ribonucleases), miRNA sponges, miRNA masks, anti-miRNA oligonucleotides, and synthetic miRNA mimics. The broad impact of developed miRNA-based therapeutics on the various events of tumorigenesis is also discussed. Above all, the focus of this review is to evaluate the results of the combined application of different miRNA-based agents and chemotherapeutic drugs for the inhibition of tumor development. Many studies indicate a considerable increase in the efficacy of anticancer therapy as a result of additive or synergistic effects of simultaneously applied therapies. Different drug combinations, such as a cocktail of antisense oligonucleotides or multipotent miRNA sponges directed at several oncogenic microRNAs belonging to the same/different miRNA families, a mixture of anti-miRNA oligonucleotides and cytostatic drugs, and a combination of synthetic miRNA mimics, have a more complex and profound effect on the various events of tumorigenesis as compared with treatment with a single miRNA-based agent or chemotherapeutic drug. These data provide strong evidence that the simultaneous application of several distinct strategies aimed at suppressing different cellular processes linked to tumorigenesis is a promising approach for cancer therapy.

FAM83D is associated with gender, AJCC stage, overall survival and disease-free survival in hepatocellular carcinoma

Prognostic significance of family with sequence similarity 83, member D (FAM83D) in hepatocellular carcinoma (HCC) patients has not been well-investigated using Gene Expression Omnibus (GEO) series and TCGA database, we compared FAM83D expression levels between tumor and adjacent tissues, and correlated FAM83D in tumors with outcomes and clinico-pathological features in HCC patients. Validated in GSE33006, GSE45436, GSE84402 and TCGA, FAM83D was significantly overexpressed in tumor tissues than that in adjacent tissues (all P<0.01). FAM83D up-regulation was significantly associated with worse overall survival (OS) and disease-free survival (DFS) in HCC patients (Log rank P=0.00583 and P=4.178E-04, respectively). Cox analysis revealed that FAM83D high expression was significantly associated with OS in HCC patients [hazard ratio (HR) = 1.44, 95% confidence interval (CI) = 1.005-2.063, P=0.047]. Additionally, patients deceased or recurred/progressed had significantly higher FAM83D mRNA levels than those living or disease-free (P=0.0011 and P=0.0238, respectively). FAM83D high expression group had significantly more male patients and advanced American Joint Committee on Cancer (AJCC) stage cases (P=0.048 and P=0.047, respectively). FAM83D mRNA were significantly overexpressed in male (P=0.0193). Compared with patients with AJCC stage I, those with AJCC stage II and stage III-IV had significantly higher FAM83D mRNA levels (P = 0.0346 and P=0.0045, respectively). In conclusion, overexpressed in tumors, FAM83D is associated with gender, AJCC stage, tumor recurrence and survival in HCC.

Development of novel predictive miRNA/target gene pathways for colorectal cancer distance metastasis to the liver using a bioinformatic approach

Background

Liver metastases are the major cause of colorectal cancer (CRC)-related deaths. However, there is no reliable clinical predictor for CRC progression to liver metastasis. In this study, we investigated possible predictors (miRNAs and biomarkers) for clinical application.

Methodology

The Gene Expression Omnibus (GEO) datasets GSE49355, GSE41258 and GSE81558 for genes and GSE54088 and GSE56350 for miRNAs were used to identify common differentially expressed genes (DEGs) and miRNAs between primary CRC tissues and liver metastases. The identified miRNAs and their targets from the DEGs were verified in datasets comprising gene, miRNA and miRNA exosome profiles of CRC patients with no distant metastases (M0) and distant metastases (M1); the interaction networks and pathways were also mapped.

Results

There were 49 upregulated and 13 downregulated DEGs and 16 downregulated and 14 upregulated miRNAs; between the DEGs and miRNA targets, there were five upregulated and four downregulated genes. MiR-20a was strongly correlated with the status of liver metastasis. MiR-20a, miR499a, and miR-576-5p were highly correlated with the metastatic outcomes. MiR-20a was significantly highly expressed in the M1 group. In an analysis of the miRNA target genes, we found that CDH2, KNG1, and MMP2 were correlated with CRC metastasis. We demonstrated a new possible pathway for CRC metastasis: miR-576-5p/F9, miR20a/MMP2, CTSK, MMP3, and miR449a/P2RY14. The regulation of IGF transport and uptake by IGFBPs, extracellular matrix organization, signal transduction and the immune system were the enriched pathways.

Conclusion

This model can predict CRC to liver metastases and the pathways involved, which can be clinically applicable.

MiR‑495 suppresses cell proliferation by directly targeting HMGA2 in lung cancer

The present study aimed to investigate the expression of microRNA-495 (miR-495) in non-small cell lung cancer (NSCLC) tissues and cells, as well as its function on the proliferation of lung cancer cells. The expression of miR-495 in 122 pairs of NSCLC tissues and matched paracarcinoma tissues, as well as in human lung cancer cell lines (A549, H460, H1650, H520 and SK-MES-1) and the normal human pulmonary bronchial epithelial cell line 16HBE was determined using reverse transcription quantitative polymerase chain reaction (RT-qPCR). As predicted by bioinformatics analysis, high mobility group A2 (HMGA2) may be a potential target gene of miR-495. In addition, the regulatory function of miR-495 on its target gene HMGA2 was evaluated using a dual-luciferase reporter assay, RT-qPCR and western blotting. Furthermore, the effect of miR-495 on the proliferation of A549 lung cancer cells was investigated using a Cell Counting Kit-8 (CCK-8) assay. The results demonstrated that the expression of miR-495 in NSCLC tissues and cells was significantly downregulated compared with the control. In addition, downregulated expression of miR-495 was associated with tumor differentiation, lymph node metastasis and tumor, node and metastasis staging. Additionally, a dual-luciferase reporter assay revealed that miR-495 could directly associated with the 3′-untranslated region of HMGA2. Upregulated expression of miR-495 significantly downregulated the mRNA and protein expression levels of HMGA2 in A549 cells. Furthermore, the results of CCK-8 assay revealed that upregulated expression of miR-495 significantly suppressed the proliferation of A549 cells; HMGA2 overexpression reversed this inhibition. In summary, the findings of the present study demonstrated that miR-495 was downregulated in NSCLC tissues and cells. In addition, miR-495 suppressed the proliferation of lung cancer cells by directly targeting HMGA2.

Epigenetic Regulation by lncRNAs: An Overview Focused on UCA1 in Colorectal Cancer

Colorectal cancers have become the second leading cause of cancer-related deaths. In particular, acquired chemoresistance and metastatic lesions occurring in colorectal cancer are a major challenge for chemotherapy treatment. Accumulating evidence shows that long non-coding (lncRNAs) are involved in the initiation, progression, and metastasis of cancer. We here discuss the epigenetic mechanisms through which lncRNAs regulate gene expression in cancer cells. In the second part of this review, we focus on the role of lncRNA Urothelial Cancer Associated 1 (UCA1) to integrate research in different types of cancer in order to decipher its putative function and mechanism of regulation in colorectal cancer cells. UCA1 is highly expressed in cancer cells and mediates transcriptional regulation on an epigenetic level through the interaction with chromatin modifiers, by direct regulation via chromatin looping and/or by sponging the action of a diversity of miRNAs. Furthermore, we discuss the role of UCA1 in the regulation of cell cycle progression and its relation to chemoresistance in colorectal cancer cells.

MicroRNA‑495 targets Notch1 to prohibit cell proliferation and invasion in oral squamous cell carcinoma

MicroRNAs (miRNAs) are associated with the initiation and progression of oral squamous cell carcinoma (OSCC) by regulating a variety of cancer‑associated behaviors. Fully understanding the regulatory mechanism of miRNAs in the pathogenesis of OSCC may provide novel promising approaches for the identification of prognostic biomarkers and therapeutic targets for this particular malignancy. In the present study, reverse transcription‑quantitative polymerase chain reaction analysis was performed to detect miRNA (miR)‑495 expression in OSCC tissues and cell lines. The effects of miR‑495 on the proliferation and invasion of OSCC cells were determined using Cell Counting Kit‑8 and Matrigel invasion assays, respectively. The mechanisms underlying the action of miR‑495 in OSCC cells were also investigated. Results from the present study revealed that miR‑495 expression was downregulated in OSCC tissues and cell lines compare with in adjacent normal tissues and human oral keratinocytes, respectively. Exogenous expression of miR‑495 restricted cell proliferation and invasion of OSCC cells in vitro. Notch1 was identified as a direct functional target of miR‑495 in OSCC. Furthermore, Notch1 knockdown exhibited inhibitory effects, similar to those induced by miR‑495 overexpression in OSCC cells. Restoration of Notch1 expression rescued the suppressive effects of miR‑495 on OSCC cell proliferation and invasion. These findings suggested an important role for miR‑495 in the regulation of OSCC cell growth and metastasis, at least partly by directly targeting Notch1. In addition, the findings of the present study revealed the potential of miR‑495 as a novel therapeutic target for the treatment of patients with OSCC.

SATB1 3'-UTR and lncRNA-UCA1 competitively bind to miR-495-3p and together regulate the proliferation and invasion of gastric cancer

High expression of special AT-rich-binding protein 1 (SATB1) correlates with the advanced TNM stage and short overall and recurrence-free survival of gastric cancer (GC). A bioinformatic analysis revealed that SATB1 3'-untranslated region (3'-UTR) and long noncoding RNA UCA1 (lncRNA-UCA1) might competitively bind to microRNA-495-3p (miR-495-3p). Interestingly, lncRNA-UCA1 is also an important contributor to GC. The current study aimed to demonstrate the potential interaction among SATB1/miR-495-3p/lncRNA-UCA1 network and their effects on GC proliferation and invasion. The expression in GC and paracancerous normal tissues were assessed using real-time polymerase chain reaction and Western blot analysis. Luciferase reporter, RNA pull-down, and transfection assays were performed to determine the interaction among SATB1/miR-495-3p/lncRNA-UCA1 network in GC cells. GC proliferation and invasion were evaluated using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, transwell invasion, and colony formation assays. Results showed higher expression of SATB1 and lncRNA-UCA1 but lower miR-495-3p expression in GC than in the normal tissues. In luciferase reporter assay, miR-495-3p bound to three seed sequences in SATB1 3'-UTR but only one in lncRNA-UCA1. SATB1 knockdown increased the combination of miR-495-3p with lncRNA-UCA1 but decreased lncRNA-UCA1 expression. Decreased lncRNA-UCA1 was also observed with the mimics increased miR-495-3p. These data suggested that SATB1 3'-UTR functions as a competing endogenous RNA of miR-495-3p and positively regulates lncRNA-UCA1. LncRNA-UCA1 knockdown only decreased SATB1 expression in MKN-45 cells but not in BGC-823 cells, which suggested that the regulatory effect of lncRNA-UCA1 on SATB1 by sponging miR-495-3p is cell-dependent. This study further identified that SATB1/miR-495-3p/lncRNA-UCA1 network is implicated in GC proliferation and invasion. The current study firstly revealed that SATB1 interacts with miR-495-3p/lncRNA-UCA1 network, whereby enhancing GC proliferation and invasion.

Suppression of microRNA-495 alleviates high-glucose-induced retinal ganglion cell apoptosis by regulating Notch/PTEN/Akt signaling

High glucose (HG)-induced apoptosis of retinal ganglion cells (RGCs) contributes to the pathogenesis of diabetic retinopathy, which is one of the most common and severe complications of diabetes mellitus. Accumulating evidence has documented that microRNAs (miRNAs) play an important role in the pathogenesis of diabetic retinopathy. However, the role of miRNAs in regulating HG-induced apoptosis of RGCs remains largely unknown. Various studies have suggested that miR-495 is an important regulator of cell apoptosis and survival. In this study, we aimed to investigate whether miR-495 is involved in regulating HG-induced apoptosis of RGCs and reveal its possible relevance in diabetic retinopathy. We found that miR-495 was significantly upregulated in HG-treated RGCs. Downregulation of miR-495 protected RGCs against HG-induced apoptosis, whereas overexpression of miR-495 had the opposite effect. Notably, Notch1 was identified as a target gene of miR-495, as miR-495 negatively regulated Notch1 expression and the Notch signaling pathway. Moreover, downregulation of miR-495 inhibited PTEN expression while promoting Akt activation. However, knockdown of Notch1 significantly abolished the protective effect of miR-495 inhibition against HG-induced apoptosis. Overall, our study suggests that downregulation of miR-495 alleviates HG-induced apoptosis of RGCs by targeting Notch1 to regulate PTEN/Akt signaling, which provides novel insights into understanding the pathogenesis of HG-induced apoptosis of RGCs.

Hsa_circ_0071589 promotes carcinogenesis via the miR-600/EZH2 axis in colorectal cancer

Previous studies have revealed that miRNAs and lncRNAs participate in the pathogenesis of colorectal cancer (CRC); however, whether circular RNAs (circRNAs) are also involved remains unclear. In the present study, qRT-PCR was used to examine the expression of hsa_circ_0071589, miR-600, and enhancer of zeste homolog 2 (EZH2) in CRC. MTT assay, colony formation assay, transwell assay, and wound-healing assay were performed to assess the effects of hsa_circ_0071589, miR-600, and EZH2 on CRC cell viability, proliferation, invasion, and migration. Bioinformatics analysis, luciferase reporter assay, and RIP assay were used to explore the correlations among hsa_circ_0071589, miR-600, and EZH2 expression in CRC cells. The results showed that hsa_circ_0071589 expression was significantly higher in CRC tissues than in normal tissues. Blockage of hsa_circ_0071589 in CRC cells inhibited tumor growth, invasion and migration. Hsa_circ_0071589 was able to promote the expression of EZH2 by acting as a sponge of miR-600. In addition, miR-600 expression was negatively correlated to hsa_circ_0071589 expression in CRC tissues. These results demonstrated that the hsa_circ_0071589/miR-600/EZH2 axis may play critical regulatory roles in the pathogenesis of CRC and may serve as a novel therapy target in CRC.

miR-455 Functions as a Tumor Suppressor Through Targeting GATA6 in Colorectal Cancer

Emerging evidence indicates that microRNAs (miRNAs) are often aberrantly expressed in human cancers. Meanwhile, the importance of miRNAs in regulating multiple cellular biological processes has been appreciated. The aim of this study was to investigate the significance of miR-455 and identify its possible mechanism in regulating colorectal cancer (CRC) progression. We found that the expression of miR-455 was sharply reduced in CRC tissues and cell lines. Importantly, the low expression of miR-455 was associated with poor overall survival of CRC patients. Overexpression of miR-455 in CRC cell lines significantly inhibited cell proliferation and migration in vitro. Moreover, GATA-binding protein 6 (GATA6), whose expression can be inversely regulated by miR-455 in CRC cell lines, was validated as a direct target of miR-455. Overall, our results revealed that miR-455 functions as a tumor suppressor, and its downregulation may contribute to CRC progression. Our study may provide a novel therapeutic target for CRC in the future.