MiR-324-5p assists ultrasonography in predicting lymph node metastasis of unifocal papillary thyroid microcarcinoma without extracapsular spread

A review on the role of miRNA-324 in various diseases

Recent studies have revealed important functions of several microRNAs (miRNAs) in the pathogenesis of human diseases. miR-324 is an example of miRNAs with crucial impacts on the pathogenesis of a wide range of disorders. Gene ontology studies have indicated possible role of miR-324 in responses of cells to the leukemia inhibitory factor, long-term synaptic potentiation, positive regulation of cytokines production and sensory perception of sound. In human, miR-324 is encoded by MIR324 gene which resides on chromosome 17p13.1. In the current manuscript, we provide a concise review of the role of miR-324 in the pathogenesis of cancers as well as non-cancerous conditions such as aneurysmal subarachnoid hemorrhage, diabetic nephropathy, epilepsy, pulmonary/renal fibrosis, ischemic stroke and ischemia reperfusion injuries. Moreover, we summarize the role of this miRNA as a prognostic marker for malignant disorders.

miR-324-5p Contributes to Cell Proliferation and Apoptosis in Pancreatic Cancer by Targeting KLF3

Pancreatic cancer cells are characterized by high cell proliferation and low cell apoptosis, but the factors involved in these processes remain to be further studied. In this study, we report that miR-324-5p regulates the proliferation and apoptosis of pancreatic cancer cells through regulating the expression of Krüppel-like factor 3 (KLF3). In both pancreatic cancer tissues and cell lines, the levels of miR-324-5p are significantly increased. Inhibition of miR-324-5p represses cell proliferation but promotes cell apoptosis, whereas overexpression of miR-324-5p exerts the opposite effect. Furthermore, we identified KLF3, a factor regulating pancreatic cancer cell proliferation and apoptosis, as a new direct downstream target of miR-324-5p. Our results suggest that miR-324-5p plays an important role in pancreatic cancer cell proliferation and apoptosis via downregulating the expression of KLF3.

MiR-324-5p/PTPRD/CEBPD axis promotes papillary thyroid carcinoma progression via microenvironment alteration

MiR-324-5p is overexpressed in papillary thyroid carcinoma (PTC) with lymph node metastasis and promotes malignant phenotypes of KTC-1 cell line. However, the detailed regulatory mechanism remains unknown. Tumor microenvironment plays a key role in tumor progression. CCAAT enhancer-binding protein delta (CEBPD) is important in immune and inflammatory responses. In this study, we investigated the interaction between miR-324-5p/PTPRD/CEBPD axis and tumor microenvironment in PTC progression. K1 and KTC-1 were transfected by lenti-CEBPD or CEBPD-sh vectors. Supernatant from different groups was harvested and added into culture media of human macrophages and HUVEC. Cell viability, colony formation, invasive and migrated cell number, and gap closure rate were elevated in lenti-CEBPD group. Compared with the control, supernatant from lenti-CEBPD group contained more abundant levels of VEGF and IL-4/IL-13, which, respectively, induced higher HUVEC invasion/migration rates and more obvious M2 marker (CD206) and genes (PPAR-γ and MRC-1) expression in macrophages. By means of luciferase reporter assay and gene manipulation, we identified that CEBPD was negatively regulated in PTC by protein tyrosine phosphatase receptor delta (PTPRD) which was the target of miR-324-5p. CEBPD-shRNA was also proved to reverse the effect of PTPRD-sh1 or miR-324-5p mimic on IL-4/IL-13 expression and HUVEC invasion. These results suggested that miR-324-5p/PTPRD/CEBPD axis was involved in the progression of PTC by inducing HUVEC invasion/migration and macrophage M2 polarization via VEGF and IL4/IL13, respectively.

microRNA-324 plays an oncogenic role in bladder cancer cell growth and motility

Background

Despite advances in the treatment of bladder cancer (BC), patients with late-stage BC have a high mortality rate. microRNA is a small, nonprotein coding RNA, and a dysfunction in its expression is frequently strongly correlated with the prognosis of patients with cancer. Aberrant expression of miR-324 has been reported to contribute to human carcinogenesis. However, the role of miR-324 in BC remains unclear.

Methods

The expression levels of miR-324-5p and miR-324-3p were analyzed by analyzing The Cancer Genome Atlas (TCGA) database and real-time polymerase chain reaction (PCR) approach. The biological role of miR-324-5p and miR-324-3p were assessed in BFTC950 cells with miR-324-5p or miR-324-3p mimics transfection, respectively.

Results

In this study, we demonstrated that high expression levels of miR-324-5p and miR-324-3p were significantly correlated with poor survival of patients with BC. Furthermore, miR-324-5p expression significantly accelerated BC cell proliferation, colony formation ability, and invasion ability, whereas miR-324-3p expression slightly increased BC cell growth and motility.

Conclusion

Our data indicated that miR-324-5p and miR-324-3p play oncogenic roles in BC cells. This finding provides a new insight into potential therapeutic targets or putative biomarkers of BC.

Long non-coding RNA TPT1-AS1 promotes cell growth and metastasis in cervical cancer via acting AS a sponge for miR-324-5p

BACKGROUND

Increasing studies confirmed that abnormal lncRNAs expression play a critical role in cervical cancer (CC) development and progression. LncRNA TPT1-AS1, a novel lncRNA, its role and underlying mechanisms involved in CC remain largely unknown.

METHODS

Colony formation, EdU and Transwell assays were used to determine colony formation, proliferation, migration and invasion in vitro. The subcutaneous tumor model and tail vein injection lung metastasis model were performed to check tumor growth and metastasis in vivo. Luciferase activity and RIP experiment were carried out to determine the interaction between miR-324-5p and TPT1-AS1.

RESULTS

We demonstrated for the first time that TPT1-AS1 expression was up-regulated in CC tissues and cell lines. High TPT1-AS1 was significantly correlated with adverse prognostic characteristics and poor survival. TPT1-AS1 overexpression and knockdown experiments revealed that TPT1-AS1 promoted cell colony formation, proliferation, migration, invasion and EMT progression of CC cells in vitro and in vivo. The underlying mechanism indicated that TPT1-AS1 functioned as an endogenous sponge for miR-324-5p in CC cells. Gain- and loss- experiment confirmed that miR-324-5p inhibited cell colony formation, proliferation, migration, invasion and EMT progression of CC cells, and mediated the biological effects of TPT1-AS1. Further investigations confirmed that SP1 was a direct target of miR-324-5p and mediated the effects of TPT1-AS1 and miR-324-5p in CC.

CONCLUSIONS

We demonstrated for the first time that TPT1-AS1 as an oncogenic lncRNA in CC progression and as a potential target for CC cure.