The tetraindole SK228 reverses the epithelial-to-mesenchymal transition of breast cancer cells by up-regulating members of the miR-200 family

Novel miR-5088-5p promotes malignancy of breast cancer by inhibiting DBC2

Breast cancer is the most common female cancer in the world. Despite the active research on metastatic breast cancer, the treatment of breast cancer patients is still difficult because the mechanism is not well known. Therefore, research on new targets and mechanisms for diagnosis and treatment of breast cancer patients is required. On the other hand, microRNA (miRNA) has the advantage of simultaneously regulating the expression of many target genes, so it has been proposed as an effective biomarker for the treatment of various diseases including cancer. This study analyzed the role and mechanism of DBC2 (deleted in breast cancer 2), which is known to inhibit its expression in breast cancer, and proposed microRNA (miR)-5088-5p, which regulates its expression. It was revealed that the biogenesis of miR-5088-5p was upregulated by hypomethylation of its promoter, promoted by Fyn, and was involved in malignancy in breast cancer. With the use of the cellular level, clinical samples, and published data, we verified that the expression patterns of DBC2 and miR-5088-5p were negatively related, suggesting the potential as novel biomarkers for the diagnosis of breast cancer patients.

Advances in the role of oxytocin receptors in human parturition

Oxytocin (OT) is a neurohypophysial hormone which has been found to play a central role in the regulation of human parturition. The most established role of oxytocin/oxytocin receptor (OT/OTR) system in human parturition is the initiation of uterine contractions, however, recent evidence have demonstrated that it may have a more complex role including initiation of inflammation, regulation of miRNA expression, as well as mediation of other non-classical oxytocin actions via receptor crosstalk with other G protein-coupled receptors (GPCRs). In this review we highlight both established and newly emerging roles of OT/OTR system in human parturition and discuss the expanding potential for OTRs as pharmacological targets in the management of preterm labour.

Nature-inspired design of tetraindoles: Optimization of the core structure and evaluation of structure-activity relationship

Building on the initial successful optimization of a novel series of tetraindoles, a second generation of the compounds with changes in the core phenyl ring was synthesized to improve anticancer properties. 17 new compounds with different rigidity, planarity, symmetry and degree of conjugation of their core structures to 5-hydroxyindole units were synthesized. All the compounds were fully characterized and tested against breast cancer cell line (MDA-MB-231). The results revealed that the core structure is required for activity and it should be aromatic, rigid, planar, symmetrical and conjugated for optimal activity. Compound 29, which has strong anticancer activity against various tumor-derived cell lines, including Mahlavu (hepatocellular), SK-HEP-1 (hepatic), HCT116 (colon), MIA PaCa-2 (pancreatic), H441 (lung papillary), A549 (lung), H460 (non-small cell lung) and CL1-5 (lung carcinoma) with IC50 values ranging from 0.19 to 3.50μM, was generated after series of successive optimizations. It was found to induce cell cycle arrest and apoptosis in vitro and inhibit tumor growth in the non-obese diabetic-severe combined immunodeficiency (NOD/SCID) mice bearing xenografted MIA PaCa-2 human pancreatic cancer.

The miRacle in Pancreatic Cancer by miRNAs: Tiny Angels or Devils in Disease Progression

Pancreatic ductal adenocarcinoma (PDAC) is an aggressive malignancy with increasing incidence and high mortality. Surgical resection is the only potentially curative treatment of patients with PDAC. Because of the late presentation of the disease, about 20 percent of patients are candidates for this treatment. The average survival of resected patients is between 12 and 20 months, with a high probability of relapse. Standard chemo and radiation therapies do not offer significant improvement of the survival of these patients. Furthermore, novel treatment options aimed at targeting oncogenes or growth factors in pancreatic cancer have proved unsuccessful. Thereby, identifying new biomarkers that can detect early stages of this disease is of critical importance. Among these biomarkers, microRNAs (miRNAs) have supplied a profitable recourse and become an attractive focus of research in PDAC. MiRNAs regulate many genes involved in the development of PDAC through mRNA degradation or translation inhibition. The possibility of intervention in the molecular mechanisms of miRNAs regulation could begin a new generation of PDAC therapies. This review summarizes the reports describing miRNAs involvement in cellular processes involving pancreatic carcinogenesis and their utility in diagnosis, survival and therapeutic potential in pancreatic cancer.

The interplay between microRNAs and Twist1 transcription factor: a systematic review

Twist1 (also known as Twist) is a transcription factor that belongs to the family of basic helix-loop-helix (bHLH) proteins. It functions as a negative regulator of epithelial gene expression and a positive regulator of mesenchymal gene expression, thereby leading to induction of the epithelial mesenchymal transition (EMT), a process in which epithelial cells acquire the motile and migratory characteristics of mesenchymal cells. In addition to regulating the expression of protein-coding genes, Twist1 regulates the expression of microRNAs (miRNAs), adding a regulatory layer to EMT induction. Interestingly, the mRNA of Twist1 represents a downstream target of miRNAs, indicating an intricate network between miRNAs and Twist1. This network was shown to play multiple roles in cancer cell migration, invasion, and metastasis. The network can induce angiogenesis, protect cells from oncogene-induced apoptosis and senescence, enhance cancer cell resistance to conventional therapies, and increase cancer stem cell (CSC) populations. Recently, miRNAs have attracted considerable attention as potential promising tools in cancer therapies. Thus, this systematic review was conducted to clarify the reciprocal link between Twist1 and miRNAs in order to provide potential candidate miRNAs for diagnostic and therapeutic approaches in cancer treatment.

MiR-200 modulates coelomocytes antibacterial activities and LPS priming via targeting Tollip in Apostichopus japonicus

In order to explore the potential roles of microRNAs (miRNAs) in regulating Toll-like receptor (TLR) pathways, we identified Toll interacting protein as a putative target of miR-200 in Apostichopus japonicus coelomocytes by RNA-seq screening (denoted as AjTollip). The positive expression profiles of miR-200 and AjTollip were detected in both LPS exposure primary coelomocytes and Vibrio splendidus challenge sea cucumber. Co-infection miR-200 mimics significantly elevated the expression of AjTollip and its down-stream molecules. In contrast, miR-200 inhibitor significantly repressed the expression of these TLR-pathway members. More importantly, miR-200 displayed not only to enhance coelomocytes antibacterial activities, but to suppress LPS priming in vitro. Overall, all these results will enhance our understanding on miR-200 regulatory roles in anti-bacterial process in sea cucumber.

miR-200a suppresses cell growth and migration by targeting MACC1 and predicts prognosis in hepatocellular carcinoma

miR-200a suppresses tumor development and progression; however, its role in tumor growth and metastasis of hepatocellular carcinoma (HCC) and the underlying mechanism have not been elucidated. In the present study, we identified that miR-200a was markedly downregulated in HCC and exerted suppressive effects on tumor cell growth and metastasis. We identified that miR-200a suppressed tumor growth and metastasis by directly targeting MACC1. In addition, HCC patients with low miR-200a expression had significantly worse prognosis than those with high expression of miR-200a. These findings suggest that miR-200a may be recognized as a novel potential biomarker to predict the survival of patients with HCCs following liver transplantation.

Pien Tze Huang inhibits metastasis of human colorectal carcinoma cells via modulation of TGF-β1/ZEB/miR-200 signaling network

Tumor metastasis, a complex process involving the spread of malignant tumor cells from a primary tumor site to a distant organ, is a major cause of failure of cancer chemotherapy. Epithelial-mesenchymal transition (EMT) is a critical step for the initiation of cancer metastasis. The processes of EMT and metastasis are highly regulated by a double-negative feedback loop consisting of TGF-β1/ZEB pathway and miR-200 family, which therefore has become a promising target for cancer chemotherapy. Pien Tze Huang (PZH), a well-known traditional Chinese formula first prescribed in the Ming Dynasty, has been demonstrated to be clinically effective in the treatment of various types of human malignancy including colorectal cancer (CRC). Our published data proposed that PZH was able to induce apoptosis, inhibit cell proliferation and tumor angiogenesis, leading to the suppression of CRC growth in vitro and in vivo. To further elucidate the mode of action of PZH, in the present study we evaluated its effects on the metastatic capacities of human colorectal carcinoma HCT-8 cells and investigated the underlying molecular mechanisms. We found that PZH significantly inhibited the migration and invasion of HCT-8 cells in a dose-dependent manner. In addition, PZH treatment inhibited the expression of key mediators of TGF-β1 signaling, such as TGF-β1, Smad2/3 and Smad4. Moreover, PZH treatment suppressed the expression of ZEB1 and ZEB2, two critical target genes of TGF-β1 pathway, leading to a decrease in the expression of mesenchymal marker N-cadherin and an increased expression of epithelial marker E-cadherin. Furthermore, PZH treatment upregulated the expression of miR-200a, miR-200b and miR-200c. Collectively, our findings in this study suggest that PZH can inhibit metastasis of colorectal cancer cells via modulating TGF-β1/ZEB/miR-200 signaling network, which might be one of the mechanisms whereby PZH exerts its anticancer function.

Functional Role of the microRNA-200 Family in Breast Morphogenesis and Neoplasia

Branching epithelial morphogenesis is closely linked to epithelial-to-mesenchymal transition (EMT), a process important in normal development and cancer progression. The miR-200 family regulates epithelial morphogenesis and EMT through a negative feedback loop with the ZEB1 and ZEB2 transcription factors. miR-200 inhibits expression of ZEB1/2 mRNA, which in turn can down-regulate the miR-200 family that further results in down-regulation of E-cadherin and induction of a mesenchymal phenotype. Recent studies show that the expression of miR-200 genes is high during late pregnancy and lactation, thereby indicating that these miRs are important for breast epithelial morphogenesis and differentiation. miR-200 genes have been studied intensively in relation to breast cancer progression and metastasis, where it has been shown that miR-200 members are down-regulated in basal-like breast cancer where the EMT phenotype is prominent. There is growing evidence that the miR-200 family is up-regulated in distal breast metastasis indicating that these miRs are important for colonization of metastatic breast cancer cells through induction of mesenchymal to epithelial transition. The dual role of miR-200 in primary and metastatic breast cancer is of interest for future therapeutic interventions, making it important to understand its role and interacting partners in more detail.