MicroRNA-30a-5p inhibits the proliferation and invasion of gastric cancer cells by targeting insulin-like growth factor 1 receptor

Lactate induces aberration in the miR-30a-DBF4 axis to promote the development of gastric cancer and weakens the sensitivity to 5-Fu

Background

Gastric cancer (GC) is one of the most common malignancies, molecular mechanism of which is still not clear. Aberrant expression of tumor-associated genes is the major cause of tumorigenesis. DBF4 is an important factor in cancers, although there is yet no report on its function and molecular mechanism in GC.

Methods

The expression of DBF4 in tumor tissues or cells of GC was detected by qRT-PCR and western blotting. Gastric cancer cell line MGC-803 and AGS were transfected with DBF4 siRNA or overexpression vector to detect the function of DBF4 in proliferation, migration and the sensitivity to 5-Fu with CCK-8 assay, colony formation assay, transwell assay, and wound healing assay. miR-30a was found to be the regulator of DBF4 by online bioinformatics software and confirmed with qRT-PCR, western blot and dual-luciferase reporter assays.

Results

In our study, increased expression of DBF4 in GC tissues was first identified through The Cancer Genome Atlas (TCGA) and later confirmed using specimens from GC patients. Furthermore, functional experiments were applied to demonstrate that DBF4 promotes cell proliferation and migration in GC cell lines, moreover weakens the sensitivity of MGC803 and AGS cells to 5-Fu. We further demonstrated that miR-30a showed significantly lower expression in GC cells and inhibited the expression of DBF4 through 3ʹ-UTR suppression. Furthermore, rescue experiments revealed that the miR-30a-DBF4 axis regulated the GC cell proliferation, migration and the sensitivity to 5-Fu. The important composition in tumor microenvironment, lactate, may be the primary factor that suppressed miR-30a to strengthen the expression of DBF4.

Conclusions

Taken together, our study was the first to identify DBF4 as a regulator of cell proliferation and migration in GC. Furthermore, our study identified the lactate-miR-30a-DBF4 axis as a crucial regulator of tumor progression and the tumor sensitivity to 5-Fu, which maybe serve useful for the development of novel therapeutic targets.

Molecular biology and immunology of gastric cancer peritoneal metastasis

Peritoneal metastases occur in 55-60% of patients with gastric cancer (GC) and are associated with a 2% 5-year overall survival rate. There are limited treatment options for these patients, and no targeted therapy or immunotherapy is available. Rational therapeutic targets remain to be found. In this review, we present the published literature and our own recent experience in molecular biology to identify important molecules and signaling pathways as well as cellular immunity involved in the peritoneal metastasis of GC. We also suggest potential novel strategies for improving the outcomes of GC patients with peritoneal metastasis.

lncRNA DLEU2 accelerates gastric cancer growth by downregulating miR-30a-5p

Introduction:

lncRNA DLEU2 has been indicated to act a crucial role in the bioprocess of cancer. But, the role and molecular mechanisms of lncRNA DLEU2 in gastric cancer (GC) remain unknown.

Methods:

The correlation of DLEU2 or miR-30a-5p with the clinical parameters and outcomes of GC patents was implemented by TCGA cohort. Cell viability and invasion were estimated by MTT and Transwell assays. The interplay between DLEU2 and miR-30a-5p was confirmed by a luciferase report assay. The effects of DLEU2 on miR-30a-5p or MMP2/9 were detected by qRT-PCR and Western blot.

Results:

We found that the enhanced expression of DLEU2 was linked to the pathological stage and poor survival in GC patients. Overexpressing DLEU2 prompted the cell proliferation and invasion of AGS cells, but silencing DLEU2 weakened these effects in MKN-28 cells. In addition, DLEU2 could negatively modulate and be bound with miR-30a-5p, which could counteract DLEU2-caused cell proliferation. High expression of miR-30a-5p was linked to a favorable survival in patients with GC.

Conclusion:

Our findings suggested that lncRNA DLEU2 could favor the growth of GC by downregulating miR-30a-5p.

Serum exosomal microRNA transcriptome profiling in subacute spinal cord injured rats

MicroRNAs (miRNAs) are involved in a series of pathology of spinal cord injury (SCI). Although, locally expressed miRNAs have advantages in studying the pathological mechanism, they cannot be used as biomarkers. The "free circulation" miRNAs can be used as biomarkers, but they have low concentration and poor stability in body fluids. Exosomal miRNAs in body fluids have many advantages comparing with free miRNAs. Therefore, we hypothesized that the specific miRNAs in the central nervous system might be transported to the peripheral circulation and concentrated in exosomes after injury. Using next-generation sequencing, miRNA profiles in serum exosomes of sham and subactue SCI rats were analyzed. The results showed that SCI can lead to changes of serum exosomal miRNAs. These changed miRNAs and their associated signaling pathways may explain the pathological mechanism of suacute SCI. More importantly, we found some valuable serum exosomal miRNAs for diagnosis and prognosis of SCI.

Impaired microRNA processing in neutrophils from rheumatoid arthritis patients confers their pathogenic profile. Modulation by biological therapies

The aim of this study was to investigate the microRNA (miRNA) expression pattern in neutrophils from rheumatoid arthritis (RA) patients and its contribution to their pathogenic profile and to analyze the effect of specific autoantibodies or inflammatory components in the regulation of miRNA in RA neutrophils and its modulation by biological therapies. Neutrophils were isolated from paired peripheral blood (PB) and synovial fluid samples of 40 patients with RA and from PB of 40 healthy donors. A miRNA array was performed using nCounter technology. Neutrophils from healthy donors were treated in vitrowith antibodies to citrullinated protein antigens isolated from RA patients and tumor necrosis factor-a (TNF-a) or interleukin-6. A number of cytokines and chemokines were analyzed. In vitro treatments of RA-neutrophils with tocilizumab or infliximab were carried out. Transfections with pre-miRNA and DICER downregulation experiments were further performed. RA-neutrophils showed a global downregulation of miRNA and genes involved in their biogenesis, alongside with an upregulation of various potential mRNA targets related to migration and inflammation. Decreased levels of miRNA and DICER correlated with autoimmunity, inflammation and disease activity. Citrullinated protein antigens and TNF-a decreased the expression of numerous miRNA and their biogenesis-related genes, increasing their potential mRNA targets. Infliximab reversed those effects. Transfections with pre-miRNA-223, -126 and -148a specifically modulated genes regulating inflammation, survival and migration whereas DICER depletion influenced the inflammatory profile of neutrophils. Taken together RA-neutrophils exhibited a global low abundance of miRNA induced by autoantibodies and inflammatory markers, which potentially contributed to their pathogenic activation. miRNA biogenesis was significantly impaired in RAneutrophils and further associated with a greater downregulation of miRNA mainly related to migration and inflammation in synovial fluid neutrophils. Finally, anti-TNF-a and anti-interleukin-6 receptor treatments can modulate miRNA levels in the neutrophils, minimizing their inflammatory profile.

MiR-30b-5p inhibits proliferation and promotes apoptosis of medulloblastoma cells via targeting MYB proto-oncogene like 2 (MYBL2)

Medulloblastoma (MB) is the most common malignant brain tumors among children. MiR-30b-5p is a potential tumor suppressor in a variety of human cancers. However, its expression and function in MB remain poorly understood. This study aimed to investigate the expression, role and regulatory mechanism of miR-30b-5p in MB. The expression of miR-30b-5p in MB tissues and cell lines was detected by real-time PCR. The effects of miR-30b-5p on cell proliferation and apoptosis were monitored by CCK-8 (Cell Counting Kit-8) assay, colony formation assay and flow cytometry, respectively. Bioinformatics database TargetScan predicted the target genes of miR-30b-5p. The interaction between miR-30b-5p and MYB proto-oncogene Like 2 (MYBL2) was determined by luciferase reporter gene assay. We demonstrated that the expression of miR-30b-5p was significantly downregulated in MB. Upregulated miR-30b-5p could inhibit the proliferation and induce apoptosis of MB.

Moreover, overexpressed miR-30b-5p could increase the expression of BAX but decrease that of Bcl-2. Downregulated miR-30b-5p exerted the opposite effect. MYBL2 was proved to be the target gene of miR-30b-5p and was negatively regulated by miR-30b-5p. These results indicate that miR-30b-5p inhibits the progression of MB via targeting the expression of MYBL2.

microRNA-30a arbitrates intestinal-type early gastric carcinogenesis by directly targeting ITGA2

BACKGROUND

Spasmolytic polypeptide-expressing metaplasia (SPEM) is considered a precursor lesion of intestinal metaplasia and intestinal-type gastric cancer (GC), but little is known about microRNA alterations during metaplasia and GC developments. Here, we investigate miR-30a expression in gastric lesions and identify its novel target gene which is associated with the intestinal-type GC.

METHODS

We conducted in situ hybridization and qRT-PCR to determine miR-30a expression in gastric tissues. miR-30a functions were determined through induction or inhibition of miR-30a in GC cell lines. A gene microarray was utilized to confirm miR-30a target genes in GC, and siRNA-mediated target gene suppression and immunostaining were performed. The Cancer Genome Atlas data were utilized to validate gene expressions.

RESULTS

We found down-regulation of miR-30a during chief cell transdifferentiation into SPEM. MiR-30a level was also reduced in the early stage of GC, and its level was maintained in advanced GC. We identified a novel target gene of miR-30a and ITGA2, and our results showed that either ectopic expression of miR-30a or ITGA2 knockdown suppressed GC cell proliferation, migration, and tumorigenesis. Levels of ITGA2 inversely correlated with levels of miR-30a in human intestinal-type GC.

CONCLUSION

We found down-regulation of miR-30a in preneoplastic lesions and its tumor-suppressive functions by targeting ITGA2 in GC. The level of ITGA2, which functions as an oncogene, was up-regulated in human GC. The results of this study suggest that coordination of the miR-30a-ITGA2 axis may serve as an important mechanism in the development of gastric precancerous lesions and intestinal-type GC.

Dietary alterations modulate the microRNA 29/30 and IGF-1/AKT signaling axis in breast Cancer liver metastasis

Background

Metastatic cancer is incurable and understanding the molecular underpinnings is crucial to improving survival for our patients. The IGF-1/Akt signaling pathway is often impaired in cancer leading to its progression and metastases. Diet modification is known to alter the IGF-1/Akt pathway and affect the expression of microRNA involved in tumor initiation, growth and metastases. Liver metastases are one of the most common type of metastases in breast and colon cancer. In the present study, we looked at the effect of diet modification on the expression of microRNA in normal liver and liver with breast cancer metastases using in vivo model.

Methodology

6-month-old C57BL/6 J mice were put on either an ad libitum (AL) diet, or 40% calorie restricted (CR) diet or were fasted for 24 h (FA) before sacrifice. MicroRNA array analysis, western blot and qRT-PCR were performed using liver tissue to compare the treatment groups. A breast cancer model was also used to study the changes in microRNA expression in liver of a group of BALB/c mice orthotopically injected with 4 T1 cells in the mammary fat pad, put on either an AL or 30% CR diet. Liver and primary tumor tissues were used to perform qRT-PCR to compare the treatment groups.

Results

MicroRNA array analysis showed significant changes in miRNA expression in both CR and FA conditions in normal liver. Expression of miR-29 and miR-30 family members was increased in both CR and FA. Western blot analysis of the normal liver tissue showed that CR and FA downregulated the IGF-1/Akt pathway and qRT-PCR showed that the expression of miR-29b, miR-29c, miR-30a and miR-30b were increased with CR and FA. Liver tissue collected from mice in the breast cancer model showed an increase in expression of miR-29b, miR-29c and miR-30b while tumor tissue showed increased expression of miR-29c, miR-30a and miR-30b.

Discussion

Members of the miR-29 family are known to target and suppress IGF-1, while members of the miR-30 family are known to target and suppress both IGF-1 and IGF-1R. In the present study, we observe that calorie restriction increased the expression of miR-29 and miR-30 in both the normal liver as well as the liver with breast cancer metastases. These findings suggest that dietary alterations may play a role in the treatment of liver metastasis, which should be evaluated further.

Targeting Transient Receptor Potential Channels by MicroRNAs Drives Tumor Development and Progression

Transient receptor potential (TRP) cation channel superfamily plays important roles in a variety of cellular processes such polymodal cellular sensing, adhesion, polarity, proliferation, differentiation and apoptosis. The expression of TRP channels is strictly regulated and their de-regulation can stimulate cancer development and progression.In human cancers, specific miRNAs are expressed in different tissues, and changes in the regulation of gene expression mediated by specific miRNAs have been associated with carcinogenesis. Several miRNAs/TRP channel pairs have been reported to play an important role in tumor biology. Thus, the TRPM1 gene regulates melanocyte/melanoma behaviour via TRPM1 and microRNA-211 transcripts. Both miR-211 and TRPM1 proteins are regulated through microphthalmia-associated transcription factor (MIFT) and the expression of miR-211 is decreased during melanoma progression. Melanocyte phenotype and melanoma behaviour strictly depend on dual TRPM1 activity, with loss of TRPM1 protein promoting melanoma aggressiveness and miR-211 expression supporting tumour suppressor. TRPM3 plays a major role in the development and progression of human clear cell renal cell carcinoma (ccRCC) with von Hippel-Lindau (VHL) loss. TRPM3, a direct target of miR-204, is enhanced in ccRCC with inactivated or deleted VHL. Loss of VHL inhibits miR-204 expression that lead to increased oncogenic autophagy. Therefore, the understanding of specific TRP channels/miRNAs molecular pathways in distinct tumors could provide a clinical rationale for target therapy in cancer.

Serum exosomal microRNA transcriptome profiling in subacute spinal cord injured rats

MicroRNAs (miRNAs) are involved in a series of pathology of spinal cord injury (SCI). Although, locally expressed miRNAs have advantages in studying the pathological mechanism, they cannot be used as biomarkers. The "free circulation" miRNAs can be used as biomarkers, but they have low concentration and poor stability in body fluids. Exosomal miRNAs in body fluids have many advantages comparing with free miRNAs. Therefore, we hypothesized that the specific miRNAs in the central nervous system might be transported to the peripheral circulation and concentrated in exosomes after injury. Using next-generation sequencing, miRNA profiles in serum exosomes of sham and subactue SCI rats were analyzed. The results showed that SCI can lead to changes of serum exosomal miRNAs. These changed miRNAs and their associated signaling pathways may explain the pathological mechanism of suacute SCI. More importantly, we found some valuable serum exosomal miRNAs for diagnosis and prognosis of SCI.

LncRNA DLEU2 accelerates the tumorigenesis and invasion of non-small cell lung cancer by sponging miR-30a-5p

Long non‐coding RNAs (lncRNAs) have been reported to participate in the pathogenesis of non–small cell lung cancer (NSCLC). However, how lncRNA deleted in lymphocytic leukaemia 2 (DLEU2) contributes to NSCLC remains undocumented. The clinical significance of lncRNA DLEU2 and miR‐30a‐5p expression in NSCLC was analysed by using fluorescence in situ hybridization and TCGA cohorts. Gain‐ and loss‐of‐function experiments as well as a NSCLC tumour model were executed to determine the role of lncRNA DLEU2 in NSCLC. DLEU2‐sponged miR‐30a‐5p was verified by luciferase reporter, and RIP assays. Herein, the expression of lncRNA DLEU2 was elevated in NSCLC tissues, and its high expression or low expression of miR‐30a‐5p acted as an independent prognostic factor of poor survival and tumour recurrence in NSCLC. Silencing of lncRNA DLEU2 repressed the tumorigenesis and invasive potential of NSCLC, whereas re‐expression of lncRNA DLEU2 showed the opposite effects. Furthermore, lncRNA DLEU2 harboured a negative correlation with miR‐30a‐5p expression in NSCLC tissues and acted as a sponge of miR‐30a‐5p, which reversed the tumour‐promoting effects of lncRNA DLEU2 by targeting putative homeodomain transcription factor 2 in NSCLC. Altogether, lncRNA DLEU2 promoted the tumorigenesis and invasion of NSCLC by sponging miR‐30a‐5p.

Identification of serum miR-30a-5p as a diagnostic and prognostic biomarker in colorectal cancer

BACKGROUND

Circulating microRNAs (miRNAs) have become increasingly appreciated in the diagnosis and prognosis of colorectal cancer (CRC).

OBJECTIVE

The aim of this study was to assess the potential diagnostic and prognostic significance of serum miR-30a-5p as a potential biomarker.

METHODS

The expression levels of serum miR-30a-5p were measured in 138 cases with CRC, 50 cases with benign lesions (colorectal adenoma and polyps) and 60 healthy volunteers by quantitative real time polymerase chain reaction (qRT-PCR).

RESULTS

The results showed that serum miR-30a-5p levels were frequently downregulated in patients with CRC and benign lesions in comparison with normal controls. Moreover, serum miR-30a-5p levels in early-stage CRC patients were significantly increased after surgery. Receiver-operating characteristic (ROC) curve analysis demonstrated serum miR-30a-5p could well distinguish CRC patients, early-stage CRC patients from healthy controls with a relative high value of area under the curve (AUC). Furthermore, low serum miR-30a-5p expression was more frequently occurred in CRC patients with aggressive clinical variables. Additionally, CRC patients exhibiting high serum miR-30a-5p expression had significantly prolonged overall survival than those exhibiting low expression. Finally, both univariate and multivariate analyses revealed that serum miR-30a-5p expression was an independent prognostic factor for overall survival in CRC patients.

CONCLUSIONS

Collectively, these findings suggested serum miR-30a-5p might act as a novel biomarker for the diagnosis and prognosis of CRC.

A comparative characterization of the circulating miRNome in whole blood and serum of HCC patients

miRNAs are considered promising non-invasive biomarkers. Serum represents the major source of biomarkers, being readily accessible for many analytical tests. Recently, whole blood has drawn increasing interest in biomarker studies due to the presence of cancer-interacting cells and circulating cancer cells. Although Hepatocellular Carcinoma (HCC) is the seventh most frequent cancer worldwide, fragmented information exists regarding the miRNome characterization in blood and serum. We profiled the circulatory miRNome of paired serum and blood samples from 20 HCC patients, identifying 274 miRNA expressed in serum and 670 in blood, most of them still uncharacterized. 157 miRNA significantly differ between the two biofluids with 28 exclusively expressed in serum. Six miRNA clusters significantly characterize the two compartments, with the cluster containing miR-4484, miR-1281, miR-3178, miR-3613-3p, miR-4532, miR-4668-5p, miR-1825, miR-4487, miR-455-3p, miR-940 having the highest average expression in serum compared to blood. The ontological analysis revealed a role of these miRNAs in cancer progression, vascular invasion and cancer immune surveillance thought the regulation of DUSP1, PD-L1 and MUC1. Taken together, these results provide the most comprehensive contribution to date towards a complete miRNome profile of blood and serum for HCC patients. We show a consistent portion of circulatory miRNAs being still unknown.

MicroRNA‑30a‑5p promotes proliferation and inhibits apoptosis of human pulmonary artery endothelial cells under hypoxia by targeting YKL‑40

Pulmonary arterial hypertension (PAH) is a fatal and currently incurable cardiopulmonary disease. Numerous microRNAs (miRNAs) serve important roles in the development of PAH. While the expression of miR-30a-5p was downregulated in the lung tissue of rats in a pulmonary hypertension rat model, the expression pattern and function of miR-30a-5p in human PAH remain unclear. Reverse transcription quantitative polymerase chain reaction (RT-qPCR) was used to examine miR-30a-5p and chitinase-3-like protein 1 (YKL-40) mRNA expression levels. The expression levels of YKL-40 and apoptosis-associated proteins were measured by western blot analysis. Cell proliferation assays and flow cytometry analysis were performed to examine cell proliferation and apoptosis, respectively. The association between miR-30a-5p and YKL-40 was determined by a luciferase reporter assay, RT-qPCR and western blot analysis. The relative expression levels of miR-30a-5p in plasma were increased in patients with PAH [median=13.23 (25th percentile=6.388, 75th percentile=21.91)] compared with normal controls [median=2.25 (25th percentile=1.4, 75th percentile=3.7). The expression of miR-30a-5p was significantly downregulated while the protein expression of YKL-40 was significantly upregulated in hypoxia-induced human pulmonary artery endothelial cells (HPAECs) when compared with the hypoxia-induced group at 0 h. miR-30a-5p overexpression promoted HPAEC growth and inhibited apoptosis of HPAECs under hypoxia. A miR-30a-5p mimic decreased the luciferase activity of a luciferase reporter construct containing YKL-40 3′-untranslated region and also decreased YKL-40 protein expression. YKL-40 overexpression partly alleviated the effects of miR-30a-5p upregulation on proliferation and apoptosis of HPAECs under hypoxia. In conclusion, the data indicated that miR-30a-5p promoted cell growth and inhibited apoptosis of HPAECs under hypoxia by targeting YKL-40. Therefore, the miR-30a-5p/YKL-40 axis may provide a potential target for the development of novel PAH therapies.

LINC00461 promotes cell migration and invasion in breast cancer through miR-30a-5p/integrin β3 axis

Mounting evidence has demonstrated that long noncoding RNAs (lncRNAs) are dysregulated and implicated in the occurrence and development of a wide range of human malignancies. LINC00461, a novel cancer-related lncRNA, has been reported to be highly expressed and serve as oncogene in glioma; however, its biological role in breast cancer (BC) remains obscure. This study aimed to explore the role of LINC00461 in BC and elucidate the potential molecular mechanisms involved. In the current study, LINC00461 was found to be significantly upregulated in both BC tissues and cell lines. Besides, we found that high LINC00461 expression was associated with TNM stage and differentiation. Furthermore, functional studies demonstrated that LINC00461 expedited BC cell migration and invasion. Notably, LINC00461 was observed to enhance the expression of vimentin and zinc-finger E-box binding homeobox factor 1, suppress the expression of E-cadherin, and promote the activation of extracellular signal-regulated kinase and AKT signaling pathways. Mechanical investigations revealed that LINC00461 positively modulated integrin β3 (ITGB3) expression as miR-30a-5p sponge in BC cells. Taken together, LINC00461 exerts an oncogenic role in BC through miR-30a-5p/ITGB3 axis. Our data indicate that LINC00461 may be used to be a novel candidate therapeutic target and a valuable diagnostic biomarker for BC.

MicroRNA-30a as a candidate underlying sex-specific differences in neonatal hyperoxic lung injury: implications for BPD

Premature male neonates are at a greater risk of developing bronchopulmonary dysplasia (BPD). The reasons underlying sexually dimorphic outcomes in premature neonates are not known. The role of miRNAs in mediating sex biases in BPD is understudied. Analysis of the pulmonary transcriptome revealed that a large percentage of angiogenesis-related differentially expressed genes are miR-30a targets. We tested the hypothesis that there is differential expression of miR-30a in vivo and in vitro in neonatal human pulmonary microvascular endothelial cells (HPMECs) upon exposure to hyperoxia. Neonatal male and female mice (C57BL/6) were exposed to hyperoxia [95% fraction of inspired oxygen (FiO2), postnatal day ( PND) 1-5] and euthanized on PND 7 and 21. HPMECs (18-24-wk gestation donors) were subjected to hyperoxia (95% O2 and 5% CO2) or normoxia (air and 5% CO2) up to 72 h. miR-30a expression was increased in both males and females in the acute phase ( PND 7) after hyperoxia exposure. However, at PND 21 (recovery phase), female mice showed significantly higher miR-30a expression in the lungs compared with male mice. Female HPMECs showed greater expression of miR-30a in vitro upon exposure to hyperoxia. Delta-like ligand 4 (Dll4) was an miR-30a target in HPMECs and showed sex-specific differential expression. miR-30a increased angiogenic sprouting in vitro in female HPMECs. Lastly, we show decreased expression of miR-30a and increased expression of DLL4 in human BPD lung samples compared with controls. These results support the hypothesis that miR-30a could, in part, contribute to the sex-specific molecular mechanisms in play that lead to the sexual dimorphism in BPD.

miR‑30a‑5p inhibits the proliferation, migration and invasion of melanoma cells by targeting SOX4

MicroRNA (miR)‑30a‑5p has been reported to suppress the progression of hepatocellular cancer, renal cell carcinoma, oral cancer and gastric cancer. However, whether miR‑30a‑5p is involved in the regulation of melanoma remains unclear. The present study revealed that miR‑30a‑5p was downregulated in melanoma tissues and cell lines. Overexpression of miR‑30a‑5p significantly inhibited the proliferation, migration and invasion of melanoma cells in vitro. In addition, ectopic expression of miR‑30a‑5p delayed tumor growth in vivo. In terms of mechanism, miR‑30a‑5p targeted sex determining region Y‑box 4 (SOX4) and impeded the expression of SOX4 in melanoma cells. In addition, SOX4 was upregulated in melanoma tissues and cell lines when compared with normal tissues or cells. Furthermore, overexpression of SOX4 significantly rescued the proliferation, migration and invasion of melanoma cells transfected with miR‑30a‑5p mimics. Taken together, the results of the present study demonstrated that miR‑30a‑5p suppressed the proliferation, migration and invasion of melanoma cells in SOX4‑dependent manner.

microRNA-30d mediated breast cancer invasion, migration, and EMT by targeting KLF11 and activating STAT3 pathway

miR-30d has been shown to play pivotal roles in cancer development, and has the potential to act as a diagnostic biomarker and therapeutic target in breast cancer. However, the specific function and molecular mechanism of miR-30d in breast cancer cell growth and metastasis is still unknown. The present study seeks to shed light on the potential contribution of the MiR-30d-KLF-11-STAT3 pathway in breast cancer. The results revealed that miR-30d levels were markedly increased in the breast cancer cell lines BT474, MDA-MB-231, HCC197, and MDA-MB-468 compared with the non-tumor mammary gland MCF10A cell line. Furthermore, the miR-30d mimic increased BT474 and MDA-MB-231 breast cancer cell survival, inhibited apoptosis and increased Bcl-2 expression, whilst inhibited Bax protein levels. miR-30d mimics promote BT474 and MDA-MB-231 cell migration, invasion, and mediate the EMT phenotype. However, miR-30d inhibitors reverse all of the effects of miR-30d mimics on breast cancer cell biology. Also, we observed that KLF-11 is a direct target of miR-30d and KLF-11 and pSTAT3 expression are determined by miR-30d. Finally, the results suggest that miR-30d plays essential roles in breast cancer cells in a manner that is dependent on the levels of KLF-1 and pSTAT3. In summary, miR-30d appears to be a novel diagnostic biomarker and treatment target in breast cancer.