miR-25-3p inhibition impairs tumorigenesis and invasion in gastric cancer cells in vitro and in vivo

MiR-25-3p regulates pulmonary arteriovenous malformation after Glenn procedure in patients with univentricular heart via the PHLPP2-HIF-1α axis

The detailed mechanism of pulmonary arteriovenous malformations after Glenn surgery (G-PAVMs) in cyanotic congenital heart disease (CHD) remains unclear. Microarray in situ hybridization was performed to assess the miRNA (miRNA) profiles of serum from pediatric patients (0-6 years of age) with G-PAVMs and after the Fontan procedure without G-PAVMs. In addition, we investigated the tube formation, migration, and proliferation of human lung microvascular endothelial cells (HMVEC-L) transfected with miR-25-3p mimic, miR-25-3p inhibitor, or PHLPP2 small interfering RNA, and examined HIF-1α/VEGF-A signaling after hypoxic stimulation. Serum miRNAs that showed ≥ 2-fold higher levels in patients with G-PAVMs than in other patients were selected. MiR-25-3p was significantly upregulated in the pulmonary artery sera of the post-Glenn group than in the post-Fontan group. We identified PHLPP2 as a direct target of miR-25-3p. PHLPP2 expression was significantly decreased in HMVEC-L transfected with miR-25-3p mimic compared to the control cells. HIF-1α and VEGF-A expression levels were increased in HMVEC-L transfected with miR-25-3p mimic compared to the control cells in a PHLPP2/Akt/mTOR signaling-dependent manner after hypoxic stimulation. MiR-25-3p promoted HMVEC-L angiogenesis, proliferation, and migration under hypoxic conditions. MiR-25-3p in the pulmonary arteries may contribute to G-PAVM development.

miR-28-3p suppresses gastric cancer growth and EMT-driven metastasis by targeting the ARF6/Hedgehog axis

Gastric cancer (GC), among the most prevalent malignant tumors globally, demonstrates a rapid metastasis rate leading to high mortality. While microRNAs (miRNAs) have been recognized as critical regulators of tumor progression, the specific role of miR-28-3p in GC remains unclear. In this study, we demonstrate that miR-28-3p acts as a tumor suppressor by inhibiting GC cell proliferation and EMT-driven migration in vitro, as well as tumor growth and metastasis in vivo. Mechanistically, miR-28-3p directly targets ADP ribosylation factor 6 (ARF6), a small GTPase identified as an oncogene in GC. We reveal that ARF6 is significantly upregulated in GC and activates the GLI1/2-dependent Hedgehog signaling pathway, promoting tumor growth and EMT. Notably, ARF6 knockdown mitigates the pro-tumor effects caused by miR-28-3p deficiency, while combined ARF6 inhibition and Hedgehog pathway suppression exhibit synergistic anti-tumor effects. This study establishes the miR-28-3p-ARF6-Hedgehog signaling axis as a critical regulatory pathway in GC progression. Our findings provide novel insights into GC pathogenesis and highlight the therapeutic potential of targeting this axis for innovative treatment strategies.

Updates on the role of epigenetics in familial mediterranean fever (FMF)

Familial Mediterranean Fever (FMF) is an autosomal recessive autoinflammatory disease caused by mutations in the MEFV (MEditerranean FeVer) gene that affects people originating from the Mediterranean Sea. The high variability in severity and clinical manifestations observed not only between ethnic groups but also between and within families is mainly related to MEFV allelic heterogeneity and to some modifying genes. In addition to the genetic factors underlying FMF, the environment plays a significant role in the development and manifestation of this disease through various epigenetic mechanisms, including DNA methylation, histone modification, and noncoding RNAs. Indeed, epigenetic events have been identified as an important pathophysiological determinant of FMF and co-factors shaping the clinical picture and outcome of the disease. Therefore, it is essential to better understand the contribution of epigenetic factors to autoinflammatory diseases, namely, FMF, to improve disease prognosis and potentially develop effective targeted therapies. In this review, we highlight the latest updates on the role of epigenetics in FMF.

Functional Mechanism of MicroRNA-25-3p in Hilar Cholangiocarcinoma Cell Proliferation and Migration Through Regulation of Dual Specificity Phosphatase 5

OBJECTIVE

Hilar cholangiocarcinoma (HCCA) is a highly aggressive biliary tract tumor. microRNAs (miRs) exert dual actions in various cancers. This paper seeks to expound on the functional mechanisms of miR-25-3p/dual specificity phosphatase 5 (DUSP5) in HCCA cell proliferation and migration.

METHODS

HCCA-related data were downloaded from GEO database to screen out differentially-expressed genes. The potential target miR (miR-25-3p) and its expression in HCCA were analyzed on Starbase. The binding relation between miR-25-3p and DUSP5 was confirmed by dual-luciferase assay. Levels of miR-25-3p and DUSP5 in FRH-0201 cells and HIBEpics were determined by RT-qPCR and Western blot. miR-25-3p and DUSP5 levels were intervened with to explore their effects on FRH-0201 cells. The apoptosis, proliferation, migration, and invasion of FRH-0201 cells were evaluated by TUNEL, CCK8, scratch healing, and Transwell assays. Flow cytometry was conducted to assess FRH-0201 cell cycle. Levels of cell cycle-related proteins were determined by Western blot.

RESULTS

DUSP5 was weakly-expressed and miR-25-3p was highly-expressed in HCCA samples and cells. miR-25-3p targeted DUSP5. miR-25-3p suppressed FRH-0201 cell apoptosis and increased cell proliferation, migration, and invasion. DUSP5 overexpression partially abrogated miR-25-3p overexpression-exerted effects on FRH-0201 cells. miR-25-3p stimulated G1/S phase transition of FRH-0201 cells by targeting DUSP5.

CONCLUSION

miR-25-3p regulated HCCA cell cycle and facilitated cell proliferation and migration by targeting DUSP5.

CircRNA B cell linker regulates cisplatin sensitivity in nonsmall cell lung cancer via microRNA-25-3p/BarH‑like homeobox 2 axis

Cisplatin (DDP) was a commonly used drug in the treatment of nonsmall cell lung cancer (NSCLC). However, the current resistance of patients to DDP seriously affected its therapeutic effect. Circular RNAs (circRNAs) have been reported to regulate drug resistance in cells. The purpose of this paper is to study the effect of circRNA B cell linker (circ_BLNK) in DDP resistance of NSCLC. The abundances of circ_BLNK, microRNA-25-3p (miR-25-3p) and BarH‑like homeobox 2 (BARX2) were examined by quantitative real-time PCR and western blot analysis. Cell proliferation and apoptosis were detected by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide assay, EdU assay and flow cytometry. Transwell assay was applied to assess cell migration and invasion. Protein levels were quantified by western blot analysis. Dual-luciferase reporter assay was enforced to confirm the links among circ_BLNK, miR-25-3p and BARX2. The mice models were enforced to evaluate tumorigenicity. Herein, circ_BLNK and BARX2 were lower-expressed, whereas miR-25-3p was higher-expressed in A549/DDP and H1299/DDP cells than their homologous parental NSCLC cells. Circ_BLNK increases improved DDP sensitivity of NSCLC cells by promoting cell apoptosis and inhibiting proliferation, migration and invasion. Moreover, we confirmed that circ_BLNK regulated BARX2 by inhibiting miR-25-3p. Accordingly, overexpression of circ_BLNK improved DDP sensitivity of NSCLC cells via miR-25-3p/BARX2 axis. Besides, circ_BLNK reduced cell resistance to DDP, thereby inhibiting tumor development in mice. Circ_BLNK promoted the DDP sensitivity of NSCLC via regulating miR-25-3p/BARX2 axis.

Overexpression of microRNA-107 suppressed proliferation, migration, invasion, and the PI3K/Akt signaling pathway and induced apoptosis by targeting Nin one binding (NOB1) protein in a hypopharyngeal squamous cell carcinoma cell line (FaDu)

Hypopharyngeal squamous cell carcinoma (HSCC) is one of the most common head and neck cancers, with a worst prognosis owing to its aggressivity. MicroRNA-107 (miR-107) is reported to regulate the progression of various cancers. Nevertheless, its implied function in HSCC remains unclear. This study is aimed to exploring the roles and potential mechanisms of miR-107 in HSCC. We found that miR-107 expression was significantly decreased in HSCC tissues compared with the para-cancer tissues. Moreover, miR-107 overexpression by miR-107 mimics decreased FaDu cell viability, led to cell cycle arrest in G1/S phase, accelerated apoptosis, and reduced cell migration and invasion. MiR-107 possibly resulted in deactivation of the phosphatidylinositol 3-kinase (PI3K)/Akt pathway, evidenced by the decrease of phosphorylated (p-) PI3K and p-Akt. Besides, dual-luciferase reporter assay confirmed that miR-107 might bind to the 3’UTR of Nin one binding protein 1 (NOB1), and elevated NOB1 expression in HSCC tissues and a negative correlation between miR-107 and NOB1 were found. Rescue assays demonstrated the significant roles of miR-107 in FaDu cell behavior by modulating NOB1. In addition, the tumorigenic potential of miR-107 in vivo was conducted. It was found that miR-107 overexpression in FaDu cells significantly inhibited tumor growth and led to inactivation of the PI3K/Akt signaling. The above findings revealed that miR-107 could suppress FaDu cell proliferation, migration, invasion and induced apoptosis by targeting NOB1 through the PI3K/Akt pathway, suggesting that miR-107/NOB1 axis may exert a key role in FaDu HSCC development.

Potential Therapeutic Action of Autophagy in Gastric Cancer Managements: Novel Treatment Strategies and Pharmacological Interventions

Gastric cancer (GC), second most leading cause of cancer-associated mortality globally, is the cancer of gastrointestinal tract in which malignant cells form in lining of the stomach, resulting in indigestion, pain, and stomach discomfort. Autophagy is an intracellular system in which misfolded, aggregated, and damaged proteins, as well as organelles, are degraded by the lysosomal pathway, and avoiding abnormal accumulation of huge quantities of harmful cellular constituents. However, the exact molecular mechanism of autophagy-mediated GC management has not been clearly elucidated. Here, we emphasized the role of autophagy in the modulation and development of GC transformation in addition to underlying the molecular mechanisms of autophagy-mediated regulation of GC. Accumulating evidences have revealed that targeting autophagy by small molecule activators or inhibitors has become one of the greatest auspicious approaches for GC managements. Particularly, it has been verified that phytochemicals play an important role in treatment as well as prevention of GC. However, use of combination therapies of autophagy modulators in order to overcome the drug resistance through GC treatment will provide novel opportunities to develop promising GC therapeutic approaches. In addition, investigations of the pathophysiological mechanism of GC with potential challenges are urgently needed, as well as limitations of the modulation of autophagy-mediated therapeutic strategies. Therefore, in this review, we would like to deliver an existing standard molecular treatment strategy focusing on the relationship between chemotherapeutic drugs and autophagy, which will help to improve the current treatments of GC patients.

Inhibition of integrin subunit alpha 11 restrains gastric cancer progression through phosphatidylinositol 3-kinase/Akt pathway

Gastric cancer (GC) is among the most frequent malignancies originating from the digestive system worldwide, while the role and specific mechanism of integrin-subunit alpha 11 (ITGA11) in GC remain unclear. This study probes the expression characteristics and function of ITGA11 in GC. Firstly, the ITGA11 profile in GC tissues and paracancerous non-tumor tissues was assessed by quantitative reverse transcription-polymerase chain reaction (qRT-PCR) and Western blot (WB), and the association between ITGA11 and GC patients' clinicopathological indicators was evaluated. ITGA11 knockdown models were set up in GC cell lines MKN45 and AGS. Cell proliferation was determined by the cell counting kit-8 (CCK-8) assay and colony formation assay. WB was utilized to gauge the expression of apoptosis-related proteins (Bax, Bcl2, Bad, and C-Caspase3) and the PI3K/AKT pathway. We discovered that the ITGA11 expression was boosted in GC tissues and was related to the unfavorable prognosis of GC patients. Additionally, ITGA11 knockdown abated GC cell proliferation, invasion and migration, and enhanced cell apoptosis. In animal experiments, the tumorigenesis of GC cells knocking down ITGA11 was reduced. Mechanically, knocking down ITGA11 notably inactivated the PI3K/AKT axis. The tumor-suppressive effect mediated by ITGA11 knockdown was attenuated after activating the PI3K/AKT pathway with insulin-like growth factor 1 (IGF-1). Overall, this study substantiated that the ITGA11 expression was heightened in GC tissues, which affected GC progression by modulating the PI3K/AKT pathway.

Clinical significance of microRNA-1180-3p for colorectal cancer and effect of its alteration on cell function

An early diagnosis and effective prognostic factors would greatly reduce the mortality rate of colorectal cancer (CRC). This research is intended to complete the evaluation of the prognostic value and potential role of miR-1180-3p in CRC. The miR-1180-3p levels were reduced in CRC patients’ tissues, blood, and human CRC cell lines. The ability of miR-1180-3p was explored in discrimination of CRC patients and healths and the value in overall survival estimate. The effect of miR-1180-3p dysregulation on the CRC cellular function was investigated. miR-1180-3p is downregulated in CRC tissues, blood and cells than normal ones. This lower expression was correlated with vascular invasion, lymph node metastasis, and TNM stage. With the use of ROC curve, miR-1180-3p showed discriminating ability in CRC patients and healthy subjects. With the result of Kaplan–Meier analysis and multi-multivariate Cox analysis, miR-1180-3p was an independent predictor for CRC patients’ overall survival. Utilizing CCK-8, Transwell and matrigel assays, overexpression of miR-1180-3p reduced cancer cell proliferation and mobility, but induced apoptosis, by targeting COL12A1. miR-1180-3p might function as a suppressor in CRC progression and allowed the discovery of a new biomarker for diagnosis, prognosis and therapy target for CRC.

A novel circular RNA circ_HN1/miR-628-5p/Ecto-5'-nucleotidase competing endogenous RNA network regulates gastric cancer development

The competing endogenous RNA (ceRNA) activity of circular RNAs (circRNAs) has been implicated in the development of gastric cancer. Here, we sought to explore the ceRNA function of circRNA Jupiter microtubule associated homolog 1 (circ_HN1) in gastric tumorigenesis. Circ_HN1, microRNA (miR)-628-5p, and NT5E expression levels were quantified by qRT-PCR and western blot. Dual-luciferase reporter assays were used to assess the direct relationship between miR-628-5p and circ_HN1 or NT5E. Our data showed that circ_HN1 expression was enhanced in human gastric cancer. Depletion of circ_HN1 impeded cell proliferation, spheroid formation, invasion, and migration and promoted apoptosis in vitro, as well as diminished tumor growth in vivo. NT5E was a downstream effector of circ_HN1 function. NT5E was targeted and inhibited by miR-628-5p through the perfect complementary site in NT5E 3ʹUTR, and circ_HN1 affected NT5E expression through miR-628-5p competition. Moreover, depletion of miR-628-5p reversed the effects of circ_HN1 silencing on regulating cell functional behaviors. Our findings identify a novel ceRNA network, the circ_HN1/miR-628-5p/NT5E axis, for the oncogenic activity of circ_HN1 in gastric cancer, highlighting circ_HN1 inhibition as a promising targeted treatment against gastric cancer.

Prognostic value of miR-1181 in non-small cell lung cancer and its regulatory effect on tumor progression

Non-small cell lung cancer (NSCLC) is one of the most important causes of cancer-related death. miR-1181 has been reported to have roles in various cancer types and its function in the progression of NSCLC was investigated in the present study. A total of 118 patients with NSCLC were recruited and their tumor tissues were collected. The expression of miR-1181 in NSCLC tissues and cells was detected by reverse transcription-quantitative PCR. The prognostic value of miR-1181 was evaluated by Kaplan-Meier and Cox regression analysis and the roles of miR-1181 in cell proliferation, migration and invasion of NSCLC were analyzed by Cell Counting Kit-8 and Transwell assays. miR-1181 was indicated to be upregulated in NSCLC tissues and cell lines, and to be associated with lymph node metastasis and the TNM stage of patients. Patients with high miR-1181 expression had a poorer prognosis than those with low miR-1181 expression. miR-1181 levels and TNM stage were determined to be two independent prognostic factors for NSCLC. In addition, overexpression of miR-1181 exerted enhancing effects on cell proliferation, migration and invasion of NSCLC, while its knockdown inhibited these cellular processes. In conclusion, upregulation of miR-1181 in NSCLC was associated with lymph node metastasis and TNM stage of patients and was indicative of poor prognosis. miR-1181 was indicated to exert promoting effects on cell proliferation, migration and invasion of NSCLC cells and to be involved in tumor progression, providing novel insight for the development of biomarkers and therapies for NSCLC.

MiR-1224 Acts as a Prognostic Biomarker and Inhibits the Progression of Gastric Cancer by Targeting SATB1

Objective

MiR-1224 has been reported to exhibit abnormal expression in several tumors. However, the expressing pattern and roles of miR-1224 in gastric cancer (GC) remain unclear. Our current research aimed to explore the potential involvement of miR-1224 in the GC progression.

Materials and Methods

The expression of miR-1224 was examined in tissue samples of 128 GC patients and cell lines by RT-PCR. Besides, the associations of miR-1224 expressions with clinicopathologic features and prognosis of GC patients were analyzed. Then, the possible influences of miR-1224 on cell proliferation and cell migration were determined. Afterward, the molecular target of miR-1224 was identified using bioinformatics assays and confirmed experimentally. Finally, RT-PCR and Western blot assays were performed to investigate the effect of the abnormal miR-1224 expression on the EMT and Wnt/β-catenin pathway.

Results

miR-1224 was lowly expressed in the GC specimens and cell lines due to T classification and TNM stage. Survival assays demonstrated that GC patients with low expressions of miR-1224 possessed poor overall survivals. Moreover, in vitro and in vivo assays revealed that the overexpression of miR-1224 inhibited cell proliferation, migration, and invasion in GC cells. SATB homeobox 1 (SATB1) was verified as a direct target of miR-1224 in GC. Furthermore, β-catenin and c-myc were significantly inhibited in miR-1224-overexpression cells.

Conclusions

Our findings highlight the potential of miR-1224 as a therapeutic target and novel biomarker for GC patients

miR-186-3p attenuates the tumorigenesis of cervical cancer via targeting insulin-like growth factor 1 to suppress PI3K-Akt signaling pathway

miR-186-3p acts as a tumor suppressor in various cancers. This study aimed to explore the expression levels of miR-186-3p and its role in cervical cancer. We analyzed the effects of miR-186-3p and insulin-like growth factor 1 (IGF1) on the proliferation, invasion, and apoptosis of cervical cancer cells in vitro by regulating the PI3K/Akt signaling pathway. In cervical cancer tissues and cells, miR-186-3p was downregulated, and IGF1 was upregulated. In addition, miR-186-3p inhibited cell proliferation and invasion and enhanced apoptosis of cervical cancer cells. Moreover, our results showed that miR-186-3p inversely regulated the mRNA expression of IGF1 through direct contact. Knockdown of IGF1 reversed the results of miR-186-3p inhibitor in cervical cancer cells. In addition, the PI3K/Akt signaling pathway was activated by the miR-186-3p inhibitor, although partially arrested by IGF1 knockdown. The PI3K/Akt signaling pathway inhibitor suppressed miR-186-3p inhibitor-stimulated cell proliferation in cervical cancer. In conclusion, miR-186-3p inhibits tumorigenesis of cervical cancer by repressing IGF1, which inactivates the PI3K/Akt signaling pathway, implicating miR-186-3p as a potential new target for the treatment of cervical cancer.

microRNA-3646 serves as a diagnostic marker and mediates the inflammatory response induced by acute coronary syndrome

Acute coronary syndrome (ACS) is one of the main syndromes of coronary artery disease with high mortality. The identification of biomarkers associated with disease occurrence and progression could improve early detection and risk prediction. This study was aimed to reveal the clinical significance and function of miR-3646 in ACS.

The expression of miR-3646 was evaluated in ACS patients, healthy volunteers, and non-ACS patients and estimated the clinical significance of miR-3646. The ACS modeling rats were also established in this study to explore the potential mechanism underlying the function of miR-3646. miR-3646 was upregulated in ACS patients compared with healthy volunteers and non-ACS patients. The expression of miR-3646 was positively correlated with the severity and progression of ACS patients and could discriminate ACS patients from healthy volunteers and non-ACS patients. The knockdown of miR-3646 could reverse the inflammatory response induced by ACS.miR-3646 serves as a diagnostic biomarker for ACS. The knockdown of miR-3646 could alleviate ACS by reversing inflammatory response. These results provide a potential therapeutic target of ACS.

N6-methyladenosine (m6A)-mediated up-regulation of long noncoding RNA LINC01320 promotes the proliferation, migration, and invasion of gastric cancer via miR495-5p/RAB19 axis

Gastric cancer is one of the most common malignant tumors. Long non-coding RNAs play crucial roles in gastric cancer progression. This study investigated the effect of LINC01320 on malignant behaviors of gastric cancer cells and explored its possible molecular mechanism. LINC01320 expression in gastric cancer tissues and cell lines was measured by qRT-PCR. Cell proliferation, transwell, and cell cloning assays were used to detect the effect of LINC01320 on the proliferation, migration, and invasion abilities, respectively, of gastric cancer cells. Bioinformatics analysis was used to predict the binding of miR-495-5p with LINC01320 and RAB19. A luciferase reporter assay was performed to verify their interactions. Finally, the N⁶-methyladenosine (m6A) modification of LINC01320 by METTL14 was identified through RIP experiments. LINC01320 was highly expressed in gastric cancer tissues and cells. LINC01320 overexpression promoted the proliferation, migration, and invasion of gastric cancer cells, while LINC01320 knockdown exerted the opposite effects. Moreover, miR-495-5p was predicted and demonstrated to target LINC01320 and RAB19. LINC01320 sponged miR-495-5p to regulate the expression of RAB19. Additionally, LINC01320-induced increases in cell viability, migration, and invasion of gastric cancer were alleviated by miR-495-5p and silenced RAB19. Furthermore, epigenetic studies showed that METTL14-mediated m6A modification led to LINC01320 up-regulation. METTL14 regulated the m6A modification of LINC01320. Overexpressed LINC01320 contributed to the aggressive phenotype of gastric cancer cells via regulating the miR-495-5p/RAB19 axis. This finding may provide new potential targets for treating gastric cancer.

Exosomal transfer of miR‑25‑3p promotes the proliferation and temozolomide resistance of glioblastoma cells by targeting FBXW7

Intrinsic or acquired resistance to temozolomide (TMZ) is a frequent occurrence in patients with glioblastoma (GBM). Accumulating evidence has indicated that the exosomal transfer of proteins and RNAs may confer TMZ resistance to recipient cells; however, the potential molecular mechanisms are not fully understood. Thus, the aim of the present study was to elucidate the possible role of exosomal microRNAs (miRNAs/miRs) in the acquired resistance to TMZ in GBM. A TMZ-resistant GBM cell line (A172R) was used, and exosomes derived from A172R cells were extracted. Exosomal miR-25-3p was identified as a miRNA associated with TMZ resistance. The potential functions of exosomal miR-25-3p were evaluated by reverse transcription-quantitative PCR, as well as cell viability, colony formation and soft agar assay, flow cytometry, western blot analysis, BrdU incorporation assay, tumor xenograft formation, luciferase reporter assay and RNA immunoprecipitation. It was found that A172R-derived exosomes promoted the proliferation and TMZ resistance of sensitive GBM cells. Moreover, miR-25-3p epxression was upregulated in the exosomes of A172R cells and in serum samples of patients with GBM treated with TMZ. The depletion of exosomal miR-25-3p partially abrogated the effects induced by the transfer of exosomes from A172R cells. By contrast, miR-25-3p overexpression facilitated the proliferation and TMZ resistance of sensitive GBM cells. F-box and WD repeat domain-containing-7 (FBXW7) was identified as a direct target of miR-25-3p. FBXW7 knockdown promoted the proliferation and TMZ resistance of GBM cells. Furthermore, the exosomal transfer of miR-25-3p promoted c-Myc and cyclin E expression by downregulating FBXW7. Our results provided a novel insight into exosomal microRNAs in acquired TMZ resistance of GBM cells. Besides, exosomal miR-25-3p might be a potential prognostic marker for GBM patients.

Long non-coding RNA LINC00511 regulates the expression of microRNA-625-5p and activates signal transducers and activators of transcription 3 (STAT3) to accelerate the progression of gastric cancer

This study aimed to investigate the expression, biological function, and downstream mechanism of LINC00511 in gastric cancer (GC). In paired GC samples, LINC00511, miR-625-5p and STAT3 mRNA expression levels were detected by quantitative real-time polymerase chain reaction (qRT-PCR); STAT3 protein expression was detected by immunohistochemical (IHC). The gain-of-function and loss-of-function models were established, and the proliferative and migrative ability of GC cells were measured by CCK-8 and transwell assays, respectively. The regulatory relationship between miR-625-5p and LINC00511 or STAT3 was examined by bioinformatics analysis, luciferase reporter gene assay, qRT-PCR, and western blot. We reported that LINC00511 and STAT3 expressions in GC tissues and cell lines were observably up-regulated, while miR-625-5p expression was inhibited. High expression of LINC00511 could facilitate the proliferation and promote the migration of GC cells. miR-625-5p was proved to be a downstream target of LINC00511, and LINC00511 could induce the expression of STAT3 by inhibiting the expression of miR-625-5p. Additionally, knockdown of LINC00511 suppressed the growth and lung metastases of CRC cells in nude mice. In conclusion, LINC00511 promotes the GC cell proliferation and migration via targeting the miR-625-5p/STAT3 axis, implying that LINC00511 can function as a target for GC therapy.

Role of microRNA-25 in high glucose cultured Müller glia

AIM

To investigate the role of microRNA-25 (miR-25) in proliferation and apoptosis of retinal Müller glia (MG) under high glucose condition.

METHODS

The purity of the cultured cells was verified by immunocytochemistry and flow cytometry using antibodies that specifically recognized MG. The expression level of miR-25 under normal and high glucose conditions were validated by quantitative reverse transcription polymerase chain reaction (RT-qPCR). miR-25 mimics and negative control were transfected into MG and multiple functional experiments including cell counting kit-8 assay, EDU assay, and flow cytometry were conducted to explore the effects of miR-25 on the proliferation and apoptosis of high glucose cultured MG (HGMG).

RESULTS

Immunocytochemistry and flow cytometry confirmed the high purity of primary cultured MG. RT-PCR results showed that the expression level of miR-25 was significantly repressed in HGMG, while over-expression of miR-25 by miR-25 mimic markedly inhibited the high glucose induced cell apoptosis and promoted the proliferation of MG.

CONCLUSION

The expression level of miR-25 is significantly downregulated in HGMG and its overexpression could attenuate the high glucose damages on MG by promoting proliferation and reducing apoptosis.

Characterization of Extracellular Vesicles Secreted in Lentiviral Producing HEK293SF Cell Cultures

Lentiviral vectors (LVs) are a powerful tool for gene and cell therapy and human embryonic kidney cells (HEK293) have been extensively used as a platform for production of these vectors. Like most cells and cellular tissues, HEK293 cells release extracellular vesicles (EVs). EVs released by cells share similar size, biophysical characteristics and even a biogenesis pathway with cell-produced enveloped viruses, making it a challenge to efficiently separate EVs from LVs. Thus, EVs co-purified with LVs during downstream processing, are considered “impurities” in the context of gene and cell therapy. A greater understanding of EVs co-purifying with LVs is needed to enable improved downstream processing. To that end, EVs from an inducible lentivirus producing cell line were studied under two conditions: non-induced and induced. EVs were identified in both conditions, with their presence confirmed by transmission electron microscopy and Western blot. EV cargos from each condition were then further characterized by a multi-omic approach. Nineteen proteins were identified by mass spectrometry as potential EV markers to differentiate EVs in LV preparations. Lipid composition of EV preparations before and after LV induction showed similar enrichment in phosphatidylserine. RNA cargos in EVs showed enrichment in transcripts involved in viral processes and binding functions. These findings provide insights on the product profile of lentiviral preparations and could support the development of improved separation strategies aimed at removing co-produced EVs.

Downregulation of microRNA‑25‑3p inhibits the proliferation and promotes the apoptosis of multiple myeloma cells via targeting the PTEN/PI3K/AKT signaling pathway

Numerous studies have confirmed that microRNAs (miRNAs or miRs) have important roles in cancer biogenesis and development including multiple myeloma (MM). MicroRNA-25-3p (miR-25-3p) has been proven to promote cancer progression, whereas its functions in MM has not yet been reported, at least to the best of our knowledge. Therefore, the present study aimed to investigate the function of miR-25-3p in MM and to identify the potential underlying mechanistic pathway. Herein, it was found that miR-25-3p expression was significantly increased in MM tissues and cell lines. The upregulation of miR-25-3p was closely associated with anemia, renal function impairment international staging system (ISS) staging and Durie-Salmon (D-S) staging. A high level of miR-25-3p was predictive of a poor prognosis of patients with MM. In vitro, the knockdown of miR-25-3p suppressed the proliferation and promoted the apoptosis of RPMI-8226 and U266 cells, while the overexpression of miR-25-3p exerted opposite effects. In addition, phosphatase and tensin homolog deleted on chromosome 10 (PTEN), a well-known tumor suppressor, was confirmed as a target of miR-25-3p in MM cells. Moreover, it was found that the PTEN expression levels were decreased, and inversely correlated with miR-25-3p expression levels in MM tissues. Further analyses revealed that the overexpression of PTEN exerted effects similar to those of miR-25-3p knockdown, whereas the knockdown of PTEN partially abolished the effects of miR-25-3p inhibitor on MM cells. Accompanied by PTEN induction, miR-25-3p promoted PI3K/AKT signaling pathway activation in MM cells. Collectively, these findings demonstrate critical roles for miR-25-3p in the pathogenesis of MM, and suggest that miR-25-3p may serve as a novel prognostic biomarker and therapeutic target of MM.

Transfer of microRNA-25 by colorectal cancer cell-derived extracellular vesicles facilitates colorectal cancer development and metastasis

Cancer cell-derived extracellular vesicles (EVs) have been reported to promote the progression of colorectal cancer (CRC), although the regulatory mechanism remains uncharacterized. In this study, we investigated the role of microRNA-25 (miR-25)/sirtuin 6 (SIRT6) in the contribution of EVs derived from CRC cells to progression of CRC. In a co-culture system with EVs from HCT116 and NCM460 cells, the viability, migratory, and invasive properties of SW480 and SW620 cells were evaluated by cell counting kit-8 (CCK-8) and Transwell assays. Luciferase, chromatin immunoprecipitation (ChIP), and RNA immunoprecipitation (RIP) assays were conducted to verify the interaction among miR-25, SIRT6, lin-28 homologB (Lin28b), and neuropilin-1 (NRP-1). It was established that HCT116 cell-derived EVs promoted the malignant properties of SW480 cells and SW620 cells by delivering miR-25. SIRT6 was targeted by miR-25, whereas SIRT6 inhibited NRP-1 through downregulation of Lin28b. The tumor-bearing nude mouse experiments substantiated that HCT116 cell-derived EVs transferred miR-25 to facilitate tumor formation and metastasis by inhibiting SIRT6. In summary, our study clarifies the involvement of miR-25-targeted SIRT6 inhibition and SIRT6-mediated inhibition of the Lin28b/NRP-1 axis in CRC cell-derived EVs to CRC progression and metastasis.

MiR-25-3p targets PTEN to regulate the migration, invasion, and apoptosis of esophageal cancer cells via the PI3K/AKT pathway

BACKGROUND

Esophageal cancer (EC) is one of the most common malignant tumors of the digestive system. MiR-25-3p was proved to be a biomarker for the diagnosis and treatment of many cancers. MiR-25-3p was found to be high expressed in the blood of EC patients. The aim of the present study was to explore the effect of miR-25-3p and its target gene on EC.

METHODS

miR-25-3p expression in the blood of EC patients and EC cells was detected by RT-qPCR. The target of miR-25-3p was identified by bioinformatics and luciferase reporter assay. After transfection, cell viability, apoptosis, migration, and invasion were detected by MTT, flow cytometry, wound healing, and transwell assays, respectively. The expressions of PTEN, Bax, Bcl-2, cleaved Caspase-3, p-PI3K, PI3K, p-AKT, and AKT were detected by Western blot.

RESULTS

MiR-25-3p was high expressed in the blood of EC patients and EC cells. MiR-25-3p targeted PTEN and inhibited the expression of PTEN. MiR-25-3p mimic increased the viability, migration, invasion and the expressions of Bcl-2, and inhibited the apoptosis and the expression of Bax and cleaved caspase-3 in EC cells. MiR-25-3p mimic also enhanced the expressions of p-PI3K and p-AKT and the ratios of p-PI3K/PI3K and p-AKT/AKT in EC cells. PTEN overexpression not only had an opposite effect of miR-25-3p mimic, but also reversed the effect of miR-25-3p mimic on EC cells.

CONCLUSION

MiR-25-3p targeted PTEN to promote the migration and invasion, and inhibit apoptosis of EC cells via the PI3K/AKT pathway, which might provide a new therapeutic target for EC treatment.

MiR-25-3p Serves as an Oncogenic MicroRNA by Downregulating the Expression of Merlin in Osteosarcoma

PURPOSE

Moesin-ezrin-radixin-like protein (Merlin) has been identified as a tumor suppressor in several types of cancers. However, the biological function of Merlin in osteosarcoma remains unclear. MicroRNAs (miRNAs) can influence cancer progression by targeting oncogenes or anti-oncogenes. In this study, we sought to evaluate the regulation of Merlin expression by miR-25-3p and the role of the miR-25-3p/Merlin axis in osteosarcoma progression, with the aim of identifying a potential therapeutic target for osteosarcoma.

MATERIALS AND METHODS

TCGA (The Cancer Genome Atlas) database was used to analyze the correlation between Merlin expression and prognosis. RT-qPCR and Western blotting analyses were performed to compare Merlin expression between normal and malignant cells. A dual-luciferase reporter assay was performed to evaluate the direct targeting of Merlin by miR-25-3p. We overexpressed miR-25-3p, or/and Merlin, in U-2 OS and 143B cells, and studied their cellular functions in vitro. MTT and colony formation assays were performed to determine the effects on cell growth. EdU and cell cycle assays were performed to analyze the effects in cell replication. We used annexin V-fluorescein isothiocyanate and propidium iodide to stain apoptotic cells, and analyzed the cells using flow cytometry. The effects on cell metastasis were studied in wound healing and transwell assays. Lastly, the underlying mechanism was determined in RT-qPCR and Western blotting experiments.

RESULTS

Low Merlin expression was linked to poor prognosis. miR-25-3p was observed to directly target Merlin and downregulate its expression. miR-25-3p promoted cell growth, migration, and invasion, and inhibited apoptosis induced by cisplatin. Moreover, the overexpression of Merlin reversed the abovementioned effects of miR-25-3p. Further, the miR-25-3p/Merlin axis was observed to play an important role in the Hippo pathway, and regulated the expression of genes such as BIRC5, CTGF, and CYR61.

CONCLUSION

miR-25-3p functions as an oncogenic microRNA in osteosarcoma by targeting Merlin, and may serve as a potential therapeutic target for osteosarcoma.