High MicroRNA-370 Expression Correlates with Tumor Progression and Poor Prognosis in Breast Cancer

Correlation Between Endoglin and Malignant Phenotype in Human Melanoma Cells: Analysis of hsa-mir-214 and hsa-mir-370 in Cells and Their Extracellular Vesicles

Endoglin (CD105) is an auxiliary receptor of transforming growth factor (TGF)-β family members that is expressed in human melanomas. It is heterogeneously expressed by primary and metastatic melanoma cells, and endoglin targeting as a therapeutic strategy for melanoma tumors is currently been explored. However, its involvement in tumor development and malignancy is not fully understood. Here, we find that endoglin expression correlates with malignancy of primary melanomas and cultured melanoma cell lines. Next, we have analyzed the effect of ectopic endoglin expression on two miRNAs (hsa-mir-214 and hsa-mir-370), both involved in melanoma tumor progression and endoglin regulation. We show that compared with control cells, overexpression of endoglin in the WM-164 melanoma cell line induces; (i) a significant increase of hsa-mir-214 levels in small extracellular vesicles (EVs) as well as an increased trend in cells; and (ii) significantly lower levels of hsa-mir-370 in the EVs fractions, whereas no significant differences were found in cells. As hsa-mir-214 and hsa-mir-370 are not just involved in melanoma tumor progression, but they can also target endoglin-expressing endothelial cells in the tumor vasculature, these results suggest a complex and differential regulatory mechanism involving the intracellular and extracellular signaling of hsa-mir-214 and hsa-mir-370 in melanoma development and progression.

MicroRNA-29b reduces myocardial ischemia-reperfusion injury in rats via down-regulating PTEN and activating the Akt/eNOS signaling pathway

Reperfusion may cause injuries to the myocardium in ischemia situation, which is called ischemia/reperfusion (I/R) injury. The study aimed to explore the roles of microRNA-29b (miR-29b) in myocardial I/R injury. Myocardial I/R injury rat model was established. Differentially expressed miRNAs between the model rats and the sham-operated rats were analyzed. miR-29b expression in myocardial tissues was measured. Gain-of-function of miR-29b was performed, and then the morphological changes, infarct size, myocardial function, oxidative stress, and the cell apoptosis in myocardial tissues were detected. The target relation between miR-29b and PTEN was detected through bio-information prediction and dual luciferase reporter gene assay. Activation of Akt/eNOS signaling was detected. H9C2 cells were subjected to hypoxia/reoxygenation treatment to perform in vitro experiments. I/R rats presented severe inflammatory infiltration, increased infarct size and cell apoptosis, increased oxidative stress and decreased myocardial function. miR-29b was downregulated in I/R rats, and up-regulation of miR-29b reversed the above changes. miR-29b directly bound to PTEN, and overexpression of miR-29b reduced PTEN expression level and increased the protein levels of p-Akt/Akt and p-eNOS/eNOS. In vivo results were confirmed in in vitro experiments. This study provided evidence that miR-29b could alleviate the myocardial I/R injury in vivo and in vitro by inhibiting PTEN expression and activating the Akt/eNOS signaling pathway.

MicroRNA-370-3p shuttled by breast cancer cell-derived extracellular vesicles induces fibroblast activation through the CYLD/Nf-κB axis to promote breast cancer progression

Breast cancer is a malignancy arising in the mammary epithelial tissues. Recent studies have indicated the abundance of microRNAs (miRNAs) in extracellular vesicles (EVs), and their interactions have been illustrated to exert crucial roles in the cell-to-cell communication. The present study focused on investigating whether EV-delivered miR-370-3p affects breast cancer. Initially, the miR-370-3p expression pattern was examined in the cancer-associated fibroblasts (CAFs), normal fibroblasts (NFs), and cancerous cells-derived EVs. The relation of miR-370-3p to CYLD was assessed using luciferase activity assay. Afterwards, based on ectopic expression and depletion experiments in the MCF-7 breast cancer cells, we evaluated stemness, migration, invasion, and sphere formation ability, and EMT, accompanied with measurement on the expression patterns of pro-inflammatory factors and nuclear factor-kappa B (NF-κB) signaling-related genes. Finally, tumorigenesis and proliferation were analyzed in vivo using a nude mouse xenograft model. The in vitro experiments revealed that breast cancer cell-derived EVs promoted NF activation, while activated fibroblasts contributed to enhanced stemness, migration, invasion, as well as EMT of cancerous cells. In addition, EVs could transfer miR-370-3p from breast cancer cells to NFs, and EV-encapsulated miR-370-3p was also found to facilitate fibroblast activation. Mechanistically, EV-encapsulated miR-370-3p downregulated the expression of CYLD through binding to its 3'UTR and activated the NF-κB signaling pathway, thereby promoting the cellular functions in vitro and in vivo in breast cancer. Taken together, EVs secreted by breast cancer cells could carry miR-370-3p to aggravate breast cancer through downregulating CYLD expression and activating the NF-κB signaling pathway.

MiR-370-5p inhibits the progression of breast cancer via targeting LUC7L3

Breast cancer is one of the most common malignancies and one of the leading causes of cancer-induced mortality among women. Over the past decades, the occurrence of breast cancer has been a significant increase. As documented in numerous researches, microRNAs (miRNAs) play vital roles in a wide range of biological processes associated with the occurrence and development of breast cancer. Nevertheless, the role of miR-370-5p in breast cancer remains obscure, and the possible molecular regulatory mechanism needs to be further explored. In this study, our results delineated that miR-370-5p was downregulated in breast cancer tissues and cell lines. Besides, miR-370-5p overexpression suppressed cell proliferation and invasion in breast cancer. MiR-370-5p downregulation exerted an opposite result. In addition, LUC7L3 was identified as a target gene for miR-370-5p. Similar with the results induced by miR-370-5p overexpression, LUC7L3 knockdown attenuated the proliferation and invasion ability of breast cancer cells. Moreover, the alternation of LUC7L3 expression reversed the regulatory effects of miR-370-5p on cell phenotypes in breast cancer. Overall, miR-370-5p may exert antitumor effect on breast cancer. Hence, miR-370-5p may serve as a novel therapeutic marker for the treatment of patients with breast cancer.

The Promising Signatures of Circulating microRNA-145 in Epithelial Ovarian Cancer Patients

BACKGROUND

Epithelial ovarian cancer continues to be a deleterious threat to women as it is asymptomatic and is typically detected in advanced stages. Cogent non-invasive biomarkers are therefore needed which are effective in apprehending the disease in early stages. Recently, miRNA deregulation has shown a promising magnitude in ovarian cancer tumorigenesis. miRNA-145(miR- 145) is beginning to be understood for its possible role in cancer development and progression. In this study, we identified the clinicopathological hallmarks altered owing to the downexpression of serum miR-145 in EOC.

METHODS

70 serum samples from histopathologically confirmed EOC patients and 70 controls were collected. Total RNA from serum was isolated by Trizol method, polyadenylated and reverse transcribed into cDNA. Expression level of miR-145 was detected by miRNA qRT-PCR using RNU6B snRNA as reference.

RESULTS

The alliance of miR-145 profiling amongst patients and controls established itself to be conspicuous with a significant p-value (p<0.0001). A positive conglomeration (p=0.04) of miR-145 profiling was manifested with histopathological grade. Receiver Operating Characteristic (ROC) curve highlights the diagnostic potential and makes it imminent with a robust Area Under the curve (AUC). A positive correlation with the ROC curve was also noted for histological grade, FIGO stage, distant metastasis, lymph node status and survival.

CONCLUSION

Our results propose that miR-145 down-regulation might be a possible touchstone for disease progression and be identified as a diagnostic marker and predict disease outcome in EOC patients.

Prognostic role of microRNAs in breast cancer: A systematic review

MicroRNAs (miRNAs) have been found to play an important role in breast cancer, functioning either as potential oncogenes or tumor suppressor genes, but their role in the prognosis of patients remains unclear. The aim of the present review study is to highlight recent preclinical and clinical studies performed on both circulating and tissue-specific miRNAs and their potential role as prognostic markers in breast cancer. We systematically searched the PubMed database to explore the prognostic value of miRNAs in breast cancer. After performing the literature search and review, 117 eligible studies were identified. We found that 110 aberrantly expressed miRNAs have been associated with prognosis in breast cancer. In conclusion, the collective data presented in this review indicate that miRNAs could serve as novel prognostic tools in breast cancer, while the clinical application of these findings has yet to be verified.

miR-762 activation confers acquired resistance to gefitinib in non-small cell lung cancer

Background

Epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitors (TKIs) (e.g. gefitinib) currently remain the first-line treatment for patients with advanced non-small-cell lung cancer (NSCLC) with activating EGFR mutation. However, acquired resistance to gefitinib, which occurs frequently through unidentified mechanisms, significantly attenuate therapeutic effectiveness. Previous miRNA microarray analysis reveals that expression levels of a conserved oncomiR miR-762 are significantly upregulated in gefitinib-resistant NSCLC cells. We therefore aim to elucidate the role and underlying mechanisms of miR-762 during the pathogenesis of gefitinib resistance.

Methods

miR-762 expression in gefitinib-resistant NSCLC tissues and cells was evaluated using RT-qPCR. The potential regulation of miR-762 expression by IL-6 was studied using pharmacological and biochemical approaches. Effects of miR-762 manipulation on sensitivity to gefitinib was assessed using MTT, apoptotic ELISA and xenograft model. Finally, the posttranscriptional regulation of active BCR related protein (ABR) by miR-762 was determined using luciferase assay and site-directed mutagenesis.

Results

miR-762 expression was upregulated in gefitinib-resistant NSCLC tissues and cells, and this upregulation predicted a poor post-chemotherapy prognosis in NSCLC patients. miR-762 upregulation, induced by IL-6 signaling, significantly enhanced cell survival and rendered NSCLC cells unresponsiveness to gefitinib-elicited cell death. We finally provided the evidence that the oncogenic effect of miR-762 was mediated mainly through posttranscriptional repression of ABR in gefitinib-resistant NSCLC cells.

Conclusions

Our findings provide a rationale for future efforts testing miR-762 inhibition and ABR restoration co-treatment in patients with recurrent EGFR mutant NSCLC to therapeutically combat the heterogeneity of EGFR-TKIs resistance mechanisms.

Glutamate metabotropic receptor 4 (GRM4) inhibits cell proliferation, migration and invasion in breast cancer and is regulated by miR-328-3p and miR-370-3p

Background

Glutamate metabotropic receptors (GRM) play a variety of roles in neuronal cells. However, their clinical significance and biological functions in breast cancer remain unknown.

Methods

RNA sequencing data of breast cancer was obtained from the TCGA dataset (v2) and mined for the expression profiles of GRM family according to cancer subtypes. mRNA expression of GRM family in breast cancer tissues and para-cancerous tissue samples as well as breast cancer cell lines were measured by qPCR. The effects of over- and under-expression of GRM4 on cell capabilities to survive, migrate and invade were determined by colony formation, transwell migration and invasion assays. To explore the upstream regulation pattern of GRM4, miRNAs that target GRM4 were predicted and validated by dual luciferase reporter assay. In addition, the mRNA and protein expression of GRM4 regulated by these miRNAs were further measured by qPCR and western blot assay.

Results

GRM4 was the only GRM member that expressed in breast cancer tissues. Ectopic expression of GRM4 was correlated with better prognosis of breast cancer patients. Overexpression of GRM4 could significantly inhibit cell proliferation, migration and invasion capacity in MDA-MB-231, while knockdown of GRM4 could promote these processes. miR-328-3p and miR-370-3p were predicted to regulate the expression of GRM4 and dual luciferase reporter assay demonstrated that miR-328-3p and miR-370-3p directly bound to the 3′ UTR of GRM4 and mutations on the binding regions on GRM4 significantly decreased the luciferase activity. qPCR demonstrated that expression of miR-328-3p and miR-370-3p was significantly decreased in breast cancer tissues and cells compared with that in control samples. However, there were no correlations between the expression of miR-328-3p and GRM4, as well as the expression of miR-370-3p and GRM4. Moreover, overexpression of miR-328-3p and miR-370-3p counteracted the inhibitory effect of GRM4-induced cell proliferation, migration and invasion.

Conclusions

Our results suggest that GRM4 might be a tumor suppressor gene in breast cancer under the direct regulation of miR-328-3p and miR-370-3p.

MicroRNA-370 protects against myocardial ischemia/reperfusion injury in mice following sevoflurane anesthetic preconditioning through PLIN5-dependent PPAR signaling pathway

Myocardial ischemia/reperfusion injury (IRI) has long been identified to be a contributor to adverse cardiovascular outcomes following myocardial ischemia, cardiac surgery or circulatory arrest. This study aims to investigate the effects of microRNA (miR-370) targeting perilipin-5 (PLIN5) in mice following sevoflurane anesthetic preconditioning (SAP). A mouse model of left ventricular myocardial IRI was established, followed by the evaluation of myocardial infarction size and cardiac function to determine the effects of SAP. The underlying regulatory mechanisms of miR-370 were analyzed in concert with the treatment of miR-370 mimic, miR-370 inhibitor, or siRNA against PLIN5 in cardiomyocytes isolated from mice with IRI. Also, cardiomyocyte proliferation, cell cycle distribution and apoptosis were evaluated following treatment. Lastly, SAP-treated I/R mice were injected with miR-370 inhibitor to verify the mechanism of SAP. The use of SAP conferred cardioprotective effects on myocardial IRI. MiR-370 was downregulated in mice that exhibited IRI, but SAP elevated the miR-370 expression. Functionally, miR-370 negatively targeted PLIN5 and activated the peroxisome proliferator activated-receptor (PPAR) signaling pathway, leading to decreased PPARγ expression but increased PPARα expression. The results also showed that elevation of miR-370 or the silencing of PLIN5 promoted cardiomyocyte proliferation. miR-370 also inhibited cardiomyocyte apoptosis as reflected by decreased caspase-3 expression and increased Bcl-2 expression. Additionally, SAP also alleviated I/R injury by inhibiting PPARγ. This study demonstrates that SAP induces miR-370 and exerts cardioprotective effects on myocardial IRI, where upregulation of miR-370 alleviates myocardial IRI via inhibiting the PLIN5-dependent PPAR signaling pathway.

Increased circulating miR-370-3p regulates steroidogenic factor 1 in endometriosis

Endometriosis is a gynecologic disease common among reproductive-aged women caused by the growth of endometrial tissue outside the uterus. Altered expression of numerous genes and microRNAs has been reported in endometriosis. Steroidogenic factor 1 (SF-1), an essential transcriptional regulator of multiple genes involved in estrogen biosynthesis, is aberrantly increased and plays an important role in the pathogenesis of endometriosis. Here, we show the expression of SF-1 in endometriosis is regulated by miR-370-3p. Sera and tissue were collected from 20 women surgically diagnosed with endometriosis and 26 women without endometriosis. We found that miR-370-3p levels were decreased in the serum of patients with endometriosis while SF-1 mRNA levels were inversely upregulated in endometriotic lesions compared with respective controls. Transfection of primary endometriotic cells with miR-370-3p mimic or inhibitor resulted in the altered expression of SF-1 and SF-1 downstream target genes steroidogenic acute regulatory protein (StAR) and CYP19A1. Overexpression of miR-370-3p inhibited cell proliferation and induced apoptosis in endometriotic cells. This study reveals that miR-370-3p functions as a negative regulator of SF-1 and cell proliferation in endometriotic cells. We suggest a novel therapeutic strategy for controlling SF-1 in endometriosis.

Perineural invasion of cancer: a complex crosstalk between cells and molecules in the perineural niche

Perineural invasion (PNI) can be found in a variety of malignant tumors. It is a sign of tumor metastasis and invasion and portends the poor prognosis of patients. The pathological description and clinical significance of PNI are clearly understood, but exploration of the underlying molecular mechanism is ongoing. It was previously thought that the low-resistance channel in the anatomic region led to the occurrence of PNI. However, with rapid development of precision medicine and molecular biology, we have gradually realized that the occurrence of PNI is not the result of a single factor. The latest study suggests that PNI of cancer is a continuous and multistep process. A specific peripheral microenvironment, also called the perineural niche, is formed by neural cells, supporting cells, recruited inflammatory cells, altered extracellular matrix, blood vessels, and immune components in the background of carcinoma. Various soluble signaling molecules and their receptors comprise a complex signal network, which achieves the interaction between nerve and tumor. Nerve cells and tumor cells can interact directly or through the opening and closing of the signal transduction pathways and/or the recognition and response of the ligands and receptors. The information is transferred to the targets accurately and effectively, leading to the specific interactions between the nerve cells and the malignant tumor cells. PNI occurs through changes in nerve cells and supporting cells in the background of cancer; change and migration of the perineural matrix; enhancement of the viability, mobility, and invasiveness of the tumor cells; injury and regeneration of nerve cells; interaction, chemotactic movement, contact, and adherence of the nerve cells and the tumor cells; escape from autophagy, apoptosis, and immunological surveillance of tumor cells; and so on. Certainly, exploring the mechanism of PNI clearly has great significance for blocking tumor progression and improving patient survival. The current review aims to elucidate the cellular and molecular mechanisms of PNI, which may help us find a strategy for improving the prognosis of malignant tumors.

MicroRNA-370 inhibits the proliferation, invasion and EMT of gastric cancer cells by directly targeting PAQR4

It has been reported that PAQR4 (Progestin and AdipoQ Receptor 4) expression is closely associated with progression of many cancers and microRNA (miRNA) processing. However, the effects and its precise mechanisms of PAQR4 in gastric cancer (GC) have not been well clarified. Our study aimed to explore the interaction between PAQR4 and miR-370 in GC. In our study, we found that the miR-370 level was significantly down-regulated in GC tissues and cell lines, and the expression of PAQR4 was dramatically increased. Interestingly, the low miR-370 level was closely associated with up-regulated PAQR4 expression in GC tissues. Moreover, introduction of miR-370 dramatically suppressed proliferation, invasion and EMT of GC cells. Whereas, miR-370 knockdown increased the proliferation, invasion and EMT in GC cells. We demonstrated that miR-370 could directly target PAQR4 by using both bioinformatics analysis and luciferase reporter assay. In addition, PAQR4 silencing had the similar effects with miR-370 overexpression on GC cells. Overexpression of PAQR4 in GC cells partially reversed the inhibitory effects of miR-370 mimic. miR-370 inhibited cell proliferation, invasion and EMT of GC cells by directly down-regulating PAQR4 expression, and miR-370 targeting PAQR4 was responsible for inhibition of the proliferation, invasion and EMT of GC cells.

MicroRNA-370 inhibits the growth and metastasis of lung cancer by down-regulating epidermal growth factor receptor expression

Abnormal microRNA-370 (miR-370) expression has been frequently reported in several types of cancers, including lung cancer. However, the role and molecular mechanisms of miR-370 in regulating the growth and metastasis of lung cancer have not been clarified. Here, we show higher levels of epidermal growth factor receptor (EGFR), but lower levels of miR-370 expression in most human lung cancer cells and non-tumor cells. Induction of miR-370 over-expression significantly reduced the levels of EGFR expression and the EGFR 3′untranslated region (UTR)-regulated luciferase activity in XWLC-05 and H157 cells, suggesting that miR-370 may bind to the 3′UTR of EGFR mRNA. Compared with the control cells, induction of miR370 overexpression significantly inhibited the proliferation, clone formation capacity, migration and invasion of XWLC-05 and H157 cells while miR-370 inhibitor over-expression enhanced their tumor behaviors in vitro. Furthermore, miR-370 over-expression down-regulated the EGFR and hypoxia-inducible factor (HIF)-1α expression, and attenuated the extracellular single-regulated kinase (ERK)1/2 and AKT phosphorylation in XWLC-05 and H157 cells. In contrast, miR370 inhibitor over-expression increased the EGFR and HIF-1α expression as well as the ERK1/2 and AKT phosphorylation in XWLC-05 and H157 cells. Moreover, miR-370 over-expression significantly reduced the levels of EGFR and CD31 expression and inhibited the growth and lung metastasis of xenograft NSCLC tumors in mice. Our study indicates that miR-370 may bind to the 3′UTR of EGFR to inhibit EGFR expression and the growth, angiogenesis and metastasis of non-small cell lung cancer by down-regulating the ERK1/2 and AKT signaling.

Identification of glycerol-3-phosphate dehydrogenase 1 as a tumour suppressor in human breast cancer

In the present study, we found the mRNA expression level of glycerol-3-phosphate dehydrogenase (GPD1) was significantly downregulated in human breast cancer patients. Patients with reduced GPD1 expression exhibited poorer overall metastatic relapse-free survival (p = 0.0013). Further Cox proportional hazard model analysis revealed that the reduced expression of GPD1 is an independent predictor of overall survival in oestrogen receptor-positive (p = 0.0027, HR = 0.91, 95% CI = 0.85–0.97, N = 3,917) and nodal-negative (p = 0.0013, HR = 0.87, 95% CI = 0.80–0.95, N = 2,456) breast cancer patients. We also demonstrated that GPD1 was a direct target of miR-370, which was significantly upregulated in human breast cancer. We further showed that exogenous expression of GPD1 in human MCF-7 and MDA-MB-231 breast cancer cells significantly inhibited cell proliferation, migration, and invasion. Our results, therefore, suggest a novel tumour suppressor function for GPD1 and contribute to the understanding of cancer metabolism.

MiR-370 functions as oncogene in melanoma by direct targeting pyruvate dehydrogenase B

BACKGROUND

Accumulating evidence has shown that miR-370 play an important role in the development and progression of tumor. However, the role of miR-370 in melanoma remains largely unknown. The present study is designed to investigate the function of miR-370 in melanoma and to explore the molecular mechanism underlying its function.

MATERIALS AND METHODS

The expression level of miR-370 was detected in melanoma tissues and cell lines by real-time quantitative polymerase chain reaction (qRT-PCR). The effect of overexpression of miR-370 on in vitro cell proliferation, apoptosis, invasion as well as glyclolysis was examined. Western blotting analysis was used to detect the influence of miR-370 on the expression of target genes, and Pearson analysis was used to calculate the correlation between the expression of targets gene and miR-370 in melanoma tissues.

RESULTS

Our study showed that miR-370 was upregulated in melanoma tissues compared with non-cancerous tissues (P<0.01). In addition, the expression of miR-370 in melanoma cell lines was also significantly higher (P<0.01). Enforced expression of miR-370 promotes melanoma cell proliferation, inhibits apoptosis and enhances invasion and glycolysis and led to downregulation of the PDHB protein. Moreover, the expression level of miR-370 in melanoma tissues showed inverse relationship with the expression level of PDHB protein.

CONCLUSIONS

In conclusion, our findings suggested that miR-370 represents a potential oncogenic miRNA and plays an important role in melanoma progression by directly targeting PDHB.

MicroRNA hsa-miR-370-3p suppresses the expression and induction of CYP2D6 by facilitating mRNA degradation

Cytochrome P450 2D6 (CYP2D6) participates in the metabolism of approximately 20-25% of prescribed drugs. Genetic polymorphisms influence the expression and/or activity of CYP2D6, and inter-individual differences in drug activation and elimination caused by CYP2D6 genetic variants were reported. However, little is known about the potential modulation of CYP2D6 expression by microRNAs (miRNAs). In the current study, by using in silico prediction of the stabilities of miRNA/mRNA complexes, we screened 38 miRNA candidates that may interact with the transcript of CYP2D6. An inverse correlation between the expression of miRNA hsa-miR-370-3p and the expression of CYP2D6 was observed in human liver tissue samples. Electrophoretic mobility shift assays confirmed that hsa-miR-370-3p was able to directly bind to its cognate target within the coding region of the CYP2D6 transcript. The transfection of hsa-miR-370-3p mimics into the HepG2^CYP2D6 cell line, a genetically modified cell line that overexpresses exogenous CYP2D6, was able to suppress the expression of CYP2D6 significantly at both mRNA and protein levels. The transfection of hsa-miR-370-3p mimics was also able to inhibit endogenous mRNA expression and/or protein production of CYP2D6 in HepaRG cells. Furthermore, in HepaRG, HepG2, and Huh7 cells, dexamethasone-induced expression of CYP2D6 was inhibited by hsa-miR-370-3p mimics. To investigate whether the miRNA mediated suppression is caused by inhibiting protein translation or promoting mRNA degradation, an actinomycin D assay was used to measure the stability of CYP2D6 transcripts. The results indicated that hsa-miR-370-3p mimics facilitated significantly the degradation of CYP2D6 mRNA. In addition, proteomics analyses of proteins isolated from the miRNA/mRNA/protein complex suggested that a group of multifunctional proteins facilitated the interaction between hsa-miR-370-3p and CYP2D6, thereby promoting mRNA degradation.

Physcion induces apoptosis in hepatocellular carcinoma by modulating miR-370

Hepatocellular carcinoma (HCC) is one of the most common and aggressive malignancies. The current study is designed to explore the role of physcion, a major active ingredient in several traditional herbal medicinal plants, for the treatment of HCC. HCC cell lines, SMMC7721 and HepG2, were treated with physcion and its apoptosis-inducing effect was examined. Both in vitro and in vivo results from the present study demonstrated that physcion treatment resulted in apoptotic cell death in HCC cells via upregulation of miR-370. Furthermore, our findings showed that the physcion modulated the level of miR-370 through AMPK/Sp1/DNMT1 signaling. Taken together, these results showed that physcion exerts anti-tumor effect against HCC, which may be a potential agent for the adjunct chemotherapy.

Alpinumisoflavone induces apoptosis in esophageal squamous cell carcinoma by modulating miR-370/PIM1 signaling

Esophageal squamous cell carcinoma (ESCC) is the most prevalent type of esophageal cancer and accumulating evidence has confirmed the role of miRNAs in ESCC. One such miRNA, miR-370, was found to be aberrantly downregulated in various human malignancies. This study showed that the expression of miR-370 was significantly lower in ESCC tissues and cell lines, and miR-370 functioned as a tumor suppressor in ESCC. Moreover, this is the first report that showed miR-370 suppresses cell proliferation and tumor growth by directly targeting Pim family kinases 1 (PIM1). Furthermore, alpinumisoflavone, a naturally occurring flavonoid, could inhibit tumor growth of ESCC by targeting miR-370/PIM1 signaling.

Down-regulation of miR-199b-5p is correlated with poor prognosis for breast cancer patients

OBJECTIVES

The purpose of the present study was to evaluate the prognostic value of miR-199b-5p in breast cancer patients, as well as explore its effects on breast cancer cells.

METHODS

The expression level of miR-199b-5p in breast cancer tissues and paired non-cancerous tissues were detected by quantitative real-time polymerase chain reaction (qRT-PCR). Chi-square test was used to evaluate the relationship between miR-199b-5p expression and clinical parameters. Besides, overall survival analysis was carried out with Kaplan-Meier curve with log rank test, and the prognostic value of miR-199b-5p in breast cancer was evaluated by cox regression model. In addition, MTT and transwell assays in vitro were used to estimate the effects of miR-199b-5p on breast cancer cells.

RESULTS

MiR-199b-5p was down-regulated in breast cancer tissues, compared with adjacent normal tissues (P<0.05). Moreover, its decreased level was significantly correlated with advanced TNM stage (P=0.008) and positive lymph node metastasis (P=0.013). Cell experiments suggested that miR-199b-5p could regulate proliferation and invasion of breast cancer cells. In addition, we found that breast cancer patients with low miR-199b-5p expression level had poorer overall survival than those with high level (log rank test, P=0.021). MiR-199b-5p was an independent prognostic factor for breast cancer patients (HR=2.318, 95%CI=1.086-4.949, P=0.030).

CONCLUSION

Down-regulated miR-199b-5p in breast cancer patients is associated with malignant clinical characteristics. MiR-199b-5p may be a potential prognostic biomarker for breast cancer.