Role and mechanism of action of LRIG1 in ovarian cancer cell line and VP16 drug-resistant cell line

Epinodosin suppresses the proliferation, invasion, and migration of esophageal squamous cell carcinoma by mediating miRNA-143-3p/Bcl-2 axis

Epinodosin has shown antibacterial and antitumor biological characteristics in the documents. We found that Epinodosin has an effective inhibitory effect on esophageal squamous cell carcinoma (ESCC). However, the potential roles and mechanisms of Epinodosin in ESCC remain unclear. We performed many experiments to clarify the effect and mechanism of Epinodosin on ESCC. In this study, cell viability, invasion, migration, and apoptosis were determined by 3-(4,5-dimethyl-2-thiazolyl)-2,-diphenytetrazoliumromide (MTT), Transwell, and flow cytometry. The differentially expressed miRNAs were screened through RNA transcriptome sequencing. The expression levels of miRNA-143-3p and some proteins were measured by real-time polymerase chain reaction (PCR) and Western blot. The anticancer effects of Epinodosin in vivo were determined by a nude mouse model. Epinodosin suppressed cell proliferation/invasion/migration and induced ESCC cell apoptosis. Epinodosin remarkably affected the protein expression of mitogen-activated protein kinase (MAPK) signaling pathway. The animal experiments demonstrated that Epinodosin could attenuate the growth of ESCC tumors in nude mice. The expression of p53, Bim, and Bax was upregulated, while that of Bcl-2 was downregulated in tumor tissues. In conclusion, Epinodosin suppresses cell viability/invasion/migration, while induces ESCC cell apoptosis by mediating miRNA-143-3p and Bcl-2, and can markedly attenuate the growth of ESCC tumors in nude mice.

miR-106b as an emerging therapeutic target in cancer

MicroRNAs (miRNAs) comprise short non-coding RNAs that function in regulating the expression of tumor suppressors or oncogenes and modulate oncogenic signaling pathways in cancer. miRNAs expression alters significantly in several tumor tissues and cancer cell lines. For example, miR-106b functions as an oncogene and increases in multiple cancers. The miR-106b directly targets genes involved in tumorigenesis, proliferation, invasion, migration, and metastases. This review has focused on the miR-106b function and its downstream target in different cancers and provide perspective into how miR-106 regulates cancer cell proliferation, migration, invasion, and metastases by regulating the tumor suppressor genes. Since miRNAs-based therapies are currently being developed to enhance cancer therapy outcomes, miR-106b could be an attractive and prospective candidate in different cancer types for detection, diagnosis, and prognosis assessment in the tumor.

DNA methyltransferase 3 beta regulates promoter methylation of microRNA-149 to augment esophageal squamous cell carcinoma development through the ring finger protein 2/Wnt/β-catenin axis

Esophageal squamous cell carcinoma (ESCC) is an aggressive form of human squamous cell carcinomas with extremely aggressive pathological features. This study explores the functions of microRNA-149 (miR-149) and its interacted molecules in ESCC. The ESCC-related miRNA and messenger RNA (mRNA) datasets were applied to identify aberrantly expressed genes in ESCC. Forty-two patients with ESCC were included and their tissue samples were collected. miR-149 was poorly expressed whereas DNA methyltransferase 3 beta (DNMT3B) and ring finger protein 2 (RNF2) were abundantly expressed in ESCC tumor samples. Overexpression of miR-149 suppressed growth and invasiveness of ESCC cells in vitro and in vivo. DNMT3B bound to the promoter region of miR-149 to trigger its promoter methylation and downregulation. RNF2 mRNA was a target of miR-149. RNF2 overexpression blocked the inhibitory effect of miR-149 on ESCC cell growth. RNF2 activated the Wnt/β-catenin pathway to promote ESCC development. In conclusion, this study found that DNMT3B downregulates miR-149 level through methylation modification of the miR-149 promoter, while miR-149 suppresses RNF2 expression and inactivates the Wnt/β-catenin pathway to suppress growth of ESCC cells.

Regulatory role of microRNAs on PTEN signaling

Phosphatase and tensin homolog (PTEN) gene encodes a tumor suppressor protein which is altered in several malignancies. This protein is a negative regulator of the PI3K/AKT signaling. Several transcription factors regulate the expression of PTEN in positive or negative directions. Moreover, numerous microRNAs (miRNAs) have functional interactions with PTEN and inhibit its expression. Suppression of PTEN can attenuate the response of cancer cells to chemotherapeutic agents. Based on the critical role of this tumor suppressor gene, the identification of negative regulators of its expression has practical significance particularly in the prevention and management of cancer. Meanwhile, the interaction between miRNAs and PTEN has functional consequences in non-malignant disorders including myocardial infarction, osteoporosis, cerebral ischemic stroke, and recurrent abortion. In the present review, we describe the role of miRNAs in the regulation of expression and activity of PTEN.

LncRNA PTENP1 inhibits cervical cancer progression by suppressing miR-106b

LncRNA PTENP1 is a competitive endogenous RNA (ceRNA) involved in decoying miR-106b in multiple diseases. This study investigates the interaction of PTENP1 and miR-106b in cell proliferation, apoptosis and epithelial-mesenchymal transition (EMT) in cervical cancer. The expressions of PTENP1, miR-106b and PTEN were determined in cervical cancer tissues, adjacent normal tissues, cervical cancer cells (HeLa, SiHa, C33A and CasKi) and normal cervical epithelial H8 cells. Up-regulation of PTENP1 and down-regulation of miR-106b were conducted in HeLa and CasKi cells by transfecting cells with corresponding miRNA mimics and inhibitors. Bioinformatics analysis, luciferase reporter assay and RNA-pull down assay were performed to verify the association of miR-106b, PTEN, and PTENP1. Cell growth and cell apoptosis were determined by CCK-8 and flow cytometry analysis. It was found that the expressions of PTENP1 and PTEN were up-regulated and that of miR-106b were down-regulated in cervical cancer tissues and cells. PTENP1 localized in cytoplasm and competitively bound to miR-106b. Up-regulation of PTENP1 and down-regulation of miR-106b contributed to increased expressions of PTEN and E-cadherin. Decreased expression of miR-106b, ZEB1, Snail and Vimentin, resulted in inhibiting cell proliferation and promoting cell apoptosis. Over-expression of PTENP1 and miR-106b accelerated cell proliferation and slowed down cell apoptosis. miR-106b inhibited the expression of PTEN. Our results suggest that LncRNA PTENP1 inhibits cervical cancer progression by competitively binding to miR-106b, leading to promote PTEN expression, inhibit cell proliferation and EMT and induce cell apoptosis in cervical cancer cells.