Overexpression of miR-1258 inhibits cell proliferation by targeting AKT3 in osteosarcoma.

Osteosarcoma (OS) has emerged as the most common primary musculoskeletal malignant tumor which affects children and adolescents. A growing number of relevant studies have shown that many microRNAs (miRNAs) play a vital regulatory role in the etiology of various types of cancer. miR-1258 has been widely studied in various cancers, but there have been few studies of its role in OS. In this present study, miR-1258 expression was dramatically decreased in OS tissues as well as OS cell lines. In addition, decreased expression of miR-1258 was significantly associated with malignant clinical manifestations and poor clinical prognosis of patients with OS. Moreover, upregulation of miR-1258 significantly inhibited cell proliferation as well as promoting cell cycle arrest at G0/G1. AKT3 was identified as a direct target of miR-1258 by binding to its 3'-UTR, and miR-1258 was negatively correlated with AKT3 expression in clinical OS tissues. AKT3 was evidently upregulated in OS tissues and cells and upregulation of AKT3 accelerated the progression of OS. Moreover, through a series of rescue experiments, we demonstrated that AKT3 can abolish the role of miR-1258 in suppressing proliferation as well as regulating the cell cycle in OS cells. In conclusion, our results suggest that the miR-1258-AKT3 axis may be a promising prognostic marker and therapeutic target for human OS.

MicroRNA-1258 suppresses oxidative stress and inflammation in septic acute lung injury through the Pknox1-regulated TGF-ß1/SMAD3 cascade.

AIM: The study was to clarify the mechanism of miR-1258 targeting Prep1 (pKnox1) to control Transforming Growth Factor ß1 (TGF-ß1)/SMAD3 pathway in septic Acute Lung Injury (ALI)-induced oxidative stress and inflammation. METHODS: BEAS-2B cells and C57BL/6 mice were used to make in vitro and in vivo septic ALI models, respectively. miR-1258 expression was checked by RT-qPCR. After transfection in the in vitro experimental model, inflammation, oxidative stress, viability, and apoptosis were observed through ELISA, MTT, and flow cytometry. RESULTS: In the in vivo model after miR-1258 overexpression treatment, inflammation, oxidative stress, and lung injury were further investigated. The targeting relationship between miR-1258 and Pknox1 was tested. Low miR-1258 was expressed in septic ALI patients, LPS-treated BEAS-2B cells, and mice. Upregulated miR-1258 prevented inflammation, oxidative stress, and apoptosis but enhanced the viability of LPS-treated BEAS-2B cells. The impact of upregulated miR-1258 on LPS-treated BEAS-2B cells was mitigated by inhibiting Pknox1 expression. MiR-1258 overexpression had the alleviating effects on inflammation, oxidative stress, and lung injury of LPS-injured mice through suppressing Pknox1 expression and TGF-ß1/SMAD3 cascade activation. CONCLUSIONS: The study concludes that miR-1258 suppresses oxidative stress and inflammation in septic ALI through the Pknox1-regulated TGF-ß1/SMAD3 cascade.

Kindlin-2-miR-1258-TCF4 feedback loop promotes hepatocellular carcinoma invasion and metastasis.

BACKGROUND: Upregulated Kindlin-2 expression in hepatocellular carcinoma (HCC) correlates with metastasis and poor prognosis. In this study, we investigated the molecular mechanism of Kindlin-2 in HCC. METHODS: Kindlin-2 downstream pathways were explored through microRNA sequencing. The Kindlin-2-miR-1258-TCF4 axis was verified using bisulfite sequencing, a luciferase reporter assay, quantitative real-time PCR, and rescue assays. Binding of TCF4 to the Kindlin-2 promoter was confirmed by promoter activity analysis and chromatin immunoprecipitation. RESULTS: MiRNA sequencing identified miR-1258 as a downstream effector of Kindlin-2. MiR-1258 expression was increased following Kindlin-2 knockdown and decreased after Kindlin-2 overexpression. Next, we identified transcription factor 7 like 2 (TCF7L2 or TCF4) as a target of miR-1258 and found that Kindlin-2 upregulated TCF4 expression by epigenetically suppressing miR-1258 in HCC. Furthermore, our results suggest that TCF4 binds to the Kindlin-2 promotor to enhance its transcription. Therefore, Kindlin-2-miR-1258-TCF4 interaction creates a positive feedback loop. Functional assays and animal experiments demonstrated critical roles of miR-1258 and TCF4 in HCC cell migration in vitro and HCC metastasis in vivo. In HCC tissues, Kindlin-2 expression correlated negatively with miR-1258 expression and positively with TCF4 expression. Meanwhile, miR-1258 expression correlated negatively with TCF4 expression. CONCLUSIONS: This study illustrates a novel integrin-independent signaling pathway, Kindlin-2-miR-1258-TCF4, that regulates HCC invasion and metastasis and identifies Kindlin-2 as a promising therapeutic target in HCC.

MicroRNA-1258: An invasion and metastasis regulator that targets heparanase in gastric cancer.

Numerous microRNAs (miRNAs/miRs) are involved in suppressing or promoting the formation of cancer. However, to the best of our knowledge, the role of miRNA-1258 in gastric cancer (GC) has not previously been investigated. Our previous study demonstrated an increased expression of heparanase (HPSE) in GC tissues and HPSE-facilitated invasion and metastasis of GC cells. Consequently, in the present study, the function of miR-1258 in the invasion and metastasis of GC cells was investigated to determine whether miR-1258 is associated with GC through HPSE. Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) was used to determine miR-1258 expression in GC cell lines and tissues. A Transwell cell invasion assay and an MTT proliferation assay were used to investigate the effects of miR-1258 on the invasion and proliferation of one of the cell lines, SGC-7901 cells, in vitro. The effect of miR-1258 on SGC-7901 cell metastasis was investigated using an in vivo tumor metastasis formation assay. Western blot analysis and RT-qPCR were used to investigate whether HPSE was a target of miR-1258 in GC. The expression of miR-1258 was significantly downregulated in 3 GC cell lines and 116 GC tissues compared with controls (all P<0.001). An association was identified between decreased miR-1258 expression level and increased age (P=0.042), advanced pathological tumor stage (P=0.027) and positive lymphatic vessel invasion (P=0.044) in patients with GC. Furthermore, the upregulation of miR-1258 expression suppressed SGC-7901 cell invasion in vitro (P<0.001) and inhibited SGC-7901 cell metastasis in vivo (P=0.016). The western blot analysis and RT-qPCR results indicated that miR-1258 downregulated the expression of HPSE at the translational level. The results of the present study indicate that miR-1258 acts as a tumor suppressor to inhibit invasion and metastasis by targeting HPSE. Therefore, miR-1258 may serve as a novel biomarker and therapeutic target in the treatment of GC.