Effect of miR-184 and miR-205 on the tumorigenesis of conjunctival mucosa associated lymphoid tissue lymphoma through regulating RasL10B and TNFAIP8

AIM: To explore the effect of miR-184 and miR-205 on the proliferation and metastasis of conjunctival mucosa associated lymphoid tissue (MALT) lymphoma. METHODS: Tissue of tumor and adjacent normal control from 5 patients with conjunctival MALT was included. RPMI8226 cell line was selected to verify the effect of miRNAs in B cells. The function of microRNA on the RPMI8226 cell apoptosis, migration and invasion was evaluated by apoptosis assay and Transwell assay. The mRNA and protein expression were examined by quantitative RT-PCR and Western blotting. The effect of microRNA on regulation of downstream gene expression was evaluated by luciferase report assay. RESULTS: A decreased level of miR-184 and miR-205 was observed in MALT lymphoma tissue. Exogenous miR-184 and miR-205 analogues promoted apoptosis, and inhibited the survival, migration, and invasion of RPMI8226 cells. miR-184 and miR-205 inhibitor reversed the process. The RNA and protein level of RasL10B and TNFAIP8 were downregulated in MALT lymphoma tissue. The exogenous of miR-184 and miR-205 promoted the expression of RasL10B and TNFAIP8. Meanwhile, inhibition of miR-184 and miR-205 repressed the expression of target gene, RasL10B and TNFAIP8. CONCLUSION: miR-184 and miR-205 suppresses the tumorigenesis of conjunctival MALT lymphoma through regulating RasL10B and TNFAIP8.

Metformin exerts anti-tumor effects via Sonic hedgehog signaling pathway by targeting AMPK in HepG2 cells

Metformin, a traditional first-line pharmacologic treatment for type 2 diabetes, has recently been shown to impart anti-cancer effects on hepatocellular carcinoma (HCC). However, the molecular mechanism of metformin on its antitumor activity is still not completely clear. The Sonic hedgehog (Shh) signaling pathway is closely associated with the initiation and progression of HCC. Therefore, the aim of the current study was to investigate the effects of metformin on the biological behavior of HCC and the underlying functional mechanism of metformin on the Shh pathway. The HCC cellular was induced in HepG2 cells by recombinant human Shh (rhShh). The effects of metformin on proliferation and metastasis were evaluated by proliferation, wound healing and invasion assays in vitro. The mRNA and protein expression levels of proteins related to the Shh pathway were measured by western blotting, quantitative PCR and immunofluorescence staining. Metformin inhibited rhShh-induced proliferation and metastasis. Furthermore, metformin decreased mRNA and protein expression of components of the Shh pathway including Shh, Ptch, Smo and Gli-1. Silencing of AMPK in the presence of metformin revealed that metformin could exert its inhibitory effect via AMPK. Our findings demonstrate that metformin can suppress the migration and invasion of HepG2 cells via AMPK-mediated inhibition of the Shh pathway.

The Role of Neuropeptide-Stimulated cAMP-EPACs Signalling in Cancer Cells

Neuropeptides are autocrine and paracrine signalling factors and mainly bind to G protein-coupled receptors (GPCRs) to trigger intracellular secondary messenger release including adenosine 3′, 5′-cyclic monophosphate (cAMP), thus modulating cancer progress in different kind of tumours. As one of the downstream effectors of cAMP, exchange proteins directly activated by cAMP (EPACs) play dual roles in cancer proliferation and metastasis. More evidence about the relationship between neuropeptides and EPAC pathways have been proposed for their potential role in cancer development; hence, this review focuses on the role of neuropeptide/GPCR system modulation of cAMP/EPACs pathways in cancers. The correlated downstream pathways between neuropeptides and EPACs in cancer cell proliferation, migration, and metastasis is discussed to glimmer the direction of future research.

Repurposing Artemisinin and its Derivatives as Anticancer Drugs: A Chance or Challenge?

Cancer has become a global health problem, accounting for one out of six deaths. Despite the recent advances in cancer therapy, there is still an ever-growing need for readily accessible new therapies. The process of drug discovery and development is arduous and takes many years, and while it is ongoing, the time for the current lead compounds to reach clinical trial phase is very long. Drug repurposing has recently gained significant attention as it expedites the process of discovering new entities for anticancer therapy. One such potential candidate is the antimalarial drug, artemisinin that has shown anticancer activities in vitro and in vivo. In this review, major molecular and cellular mechanisms underlying the anticancer effect of artemisinin and its derivatives are summarised. Furthermore, major mechanisms of action and some key signaling pathways of this group of compounds have been reviewed to explore potential targets that contribute to the proliferation and metastasis of tumor cells. Despite its established profile in malaria treatment, pharmacokinetic properties, anticancer potency, and current formulations that hinder the clinical translation of artemisinin as an anticancer agent, have been discussed. Finally, potential solutions or new strategies are identified to overcome the bottlenecks in repurposing artemisinin-type compounds as anticancer drugs.