Expression and Clinical Pathological Significance of miR-200a in Concurrent Cholangiocarcinoma Associated with Hepatolithiasis

The role of miR-200 family in the regulation of hallmarks of cancer

MiRNAs are short non-coding RNAs that regulate gene expression post-transcriptionally contributing to the development of different diseases including cancer. The miR-200 family consists of five members, miR-200a, miR-200b, miR-200c, miR-141, and miR-429. Their expression is dysregulated in cancer tissue and their level is altered in the body fluids of cancer patients. Moreover, the levels of miR-200 family members correlate with clinical parameters such as cancer patients' survival which makes them potentially useful as diagnostic and prognostic biomarkers. MiRNAs can act as either oncomiRs or tumor suppressor miRNAs depending on the target genes and their role in the regulation of key oncogenic signaling pathways. In most types of cancer, the miR-200 family acts as tumor suppressor miRNA and regulates all features of cancer. In this review, we summarized the expression pattern of the miR-200 family in different types of cancer and their potential utility as biomarkers. Moreover, we comprehensively described the role of miR-200 family members in the regulation of all hallmarks of cancer proposed by Hanahan and Weinberg with the focus on the epithelial-mesenchymal transition, invasiveness, and metastasis of tumor cells.

Long non‑coding RNA ZEB1‑AS1 predicts a poor prognosis and promotes cancer progression through the miR‑200a/ZEB1 signaling pathway in intrahepatic cholangiocarcinoma

Emerging evidence suggests that long non‑coding RNAs (lncRNAs) play pivotal roles in cancer progression, including in intrahepatic cholangiocarcinoma (IHCC). The overexpression of lncRNA ZEB1 antisense 1 (ZEB1‑AS1) has been discovered in several types of cancer; however, the clinical significance and functional role of ZEB1‑AS1 in IHCC have not yet been determined. In the present study, ZEB1‑AS1 was found to be upregulated in IHCC cell lines and tissues. A high ZEB1‑AS1 expression was associated with clinical progression and a poor survival of patients with IHCC, and was identified as an independent risk factor for a poor prognosis. In addition, ZEB1‑AS1 promoted the proliferation and metastasis of IHCC cells both in vitro and in vivo. ZEB1‑AS1 was demonstrated to increase the expression of ZEB1 by sponging miR‑200a and to thereby accelerate epithelial‑mesenchymal transition (EMT). On the whole, the findings of the present study demonstrate that ZEB1‑AS1 promotes proliferation and metastasis in IHCC, and induces EMT through the miR‑200a/ZEB1 signaling pathway. ZEB1‑AS1 may thus be a promising prognostic biomarker and essential therapeutic target for IHCC.

Down-regulation of microRNA-200b is a potential prognostic marker of lung cancer in southern-central Chinese population

MicroRNAs (miRNAs) may regulate diverse biological processes and play an important role in cancer. And MiRNAs have been proposed as a useful tool for lung cancer diagnosis and therapeutics in cancer. The purpose of the present study was to investigate the association among the expression level of mature miR-200b-5p in peripheral blood and the risk of lung cancer and clinic pathological characteristics. This case-control study included 24 patients with lung cancer and 12 healthy controls. MiR-200b expression was deleted using real-time PCR. and the miR-200b expression of normal controls was significantly higher than that in lung cancer patients (1732.13 pg/mL vs 881.67 pg/mL, P < 0.05), no difference with age, sex, tissue type and clinical stage of lung cancer patients (P > 0.05). Furthermore, miR-200b expression level fluctuated with tumor progression in lung cancer, and there was highly significant for clinical stage II compared with the clinical stage III (P < 0.05). In addition, the down-regulation of miR-200b showed a highly discriminative receiver operating characteristic (ROC) curve profile, clearly distinguishing cancer patients from cancer-free subjects with an area under the ROC curve (AUROC) of 0.87. The detection of miR-200b expression yielded 83.30% sensitivity and 100.00% specificity in the diagnosis of lung cancer. Therefore, these findings suggested that miR-200b may be used as a marker for the detection and diagnosis of lung cancer in peripheral blood.

microRNA-200a-3p enhances mitochondrial elongation by targeting mitochondrial fission factor

Mitochondria play pivotal roles in the ATP production, apoptosis and generation of reactive oxygen species. Although dynamic regulation of mitochondria morphology is a critical step to maintain cellular homeostasis, the regulatory mechanisms are not yet fully elucidated. In this study, we identified miR-200a-3p as a novel regulator of mitochondrial dynamics by targeting mitochondrial fission factor (MFF). We demonstrated that the ectopic expression of miR-200a-3p enhanced mitochondrial elongation, mitochondrial ATP synthesis, mitochondrial membrane potential and oxygen consumption rate. These results indicate that miR-200a-3p positively regulates mitochondrial elongation by downregulating MFF expression.

miRNA and lncRNA as biomarkers in cholangiocarcinoma(CCA)

The microRNAs are a group of 20 nucleotides-long non-coding RNAs. By binding to the 3'UTR region of target mRNA, microRNAs can perform extensive actions mediating gene expression at post-trancriptional stages. It makes microRNAs serve as very crucial regulators in various biological progress including carcinogenesis. Long non-coding RNAs, however, are a subgroup of RNA with the length of 200 nucleotides. Unlike microRNAs, long non-coding RNAs can form secondary of tertiary domain based on their length. With the ability of directly interacting with DNA, RNA, protein, long non-coding RNAs have promoting or inhibitive functions in gene expression regulation. Furthermore, the abnormal expression of certain long non-coding RNAs has roused people's interest in the role of long non-coding RNAs in tumorigenesis. Although the connection between microRNA/long non-coding RNA and CCA has been a hot field to researchers, the link between molecular mechanism and clinical outcome has been barely built. This review takes a retrospect at the latest researches on the link between microRNA/long non-coding RNA and cholangiocarcinoma and the potential of microRNA/long non-coding RNA serving as distinctive biomarkers for CCA in clinical practice.

MiR-200a and miR-200b target PTEN to regulate the endometrial cancer cell growth in vitro

OBJECTIVE

To study whether miR-200a and miR-200b target PTEN gene expression to regulate the endometrial cancer cell growth in vitro.

METHODS

Endometrial cancer cells ECC-1 were cultured and transfected with the miR-200a and miR-200b mimics and inhibitors as well as the negative control mimics and inhibitors, and then the cell proliferation activity as well as the expression of PTEN and downstream genes in cells was determined; after transfection of miR-200a and miR-200b mimics as well as PTEN-3'UTR luciferase report gene plasmids, the fluorescence activity of luciferase reporter gene was determined.

RESULTS

12 h, 24 h and 48 h after transfection, the cell proliferation activity of miR-200a mimics group and miR-200b mimics group were significantly higher than those of NC mimics group while the cell proliferation activity of miR-200a inhibitor group and miR-200b inhibitor group were significantly lower than those of NC inhibitor group; 48 h after transfection, PTEN expression in cells and PTEN-3'UTR luciferase reporter gene fluorescence activity of miR-200a mimics group and miR-200b mimics group were significantly lower than those of NC mimics group while p-PI3K and p-Akt expression were significantly higher than those of NC mimics group; PTEN expression in cells and PTEN-3'UTR luciferase reporter gene fluorescence activity of miR-200a inhibitor group and miR-200b inhibitor group were significantly higher than those of NC inhibitor group while p-PI3K and p-Akt expression were significantly lower than those of NC inhibitor group.

CONCLUSION

miR-200a and miR-200b can promote the endometrial cancer cell growth in vitro by targeted inhibition of PTEN gene expression.