MicroRNAs (miRNAs) are emerging as important regulators in various pathobiological processes in cancer. Genistein, as a major isoflavonoid isolated from dietary soybean, possesses a wide variety of biological activities particularly in cancer prevention. However, the molecular mechanisms by which genistein elicits its effects on ovarian cancer cells have not been fully elucidated. In this study, we reported that expression of miR-27a was higher in human ovarian cancer relative to benign ovarian tissues. Meanwhile, transfection of SKOV3 cells with the inhibitor of miR-27a suppressed growth and migration of tumor cells. Our study also found that treatment of ovarian cancer cells with genistein caused an inhibition of ovarian cancer cell growth and migration. Further cellular mechanistic studies revealed that genistein down-regulated miR-27a expression, which was accompanied by significantly increased expression of Sprouty2, a putative miR-27a target gene. Taken together, our findings reveal that oncogenic miR-27a plays an important role in ovarian cancer cell growth and metastasis, and genistein, as nontoxic inactivators of miRNA, can block ovarian cancer cell growth and migration, offering novel insights into the mechanisms of genistein therapeutic actions.

Licochalcone A (LicA) is a chalcone extracted from liquorice which has been used as a traditional Chinese medicine for many generations. Increased glucose consumption and glycolytic activity are important hallmarks of cancer cells, and hexokinase 2 (HK2) upregulation is a major contributor to the elevation of glycolysis. Recently, the antitumor activities of LicA have been reported in various cancers; however, its effect on tumor glycolysis in gastric cancer and the underlying mechanisms are completely unknown. In vitro, cell proliferation and clonogenic survival were substantially inhibited after LicA treatment. LicA reduced HK2 expression, and both glucose consumption and lactate production in gastric cancer cells were significantly suppressed. Mechanistic investigations revealed that multiple signaling pathways including Akt, ERK and NF‑κB were suppressed by LicA. Further studies demonstrated that the inhibition of glycolysis by LicA was mainly attributed to the blockade of the Akt signaling pathway, and the suppression of glycolysis was substantially attenuated when Akt was exogenously overexpressed. In addition to the role in the inhibition of glycolysis, reduction in HK2 was confirmed to be involved in the induction of cell apoptosis. The apoptosis induced by LicA was substantially impaired after HK2 overexpression in gastric cancer cells. The in vivo experiment showed that MKN45 xenograft growth was markedly delayed after LicA treatment and HK2 expression in LicA‑treated tissues was markedly decreased. All of these data demonstrated that blockade of the Akt/HK2 pathway was the underlying mechanism required for LicA to exert its biological activities in glycolysis inhibition and apoptosis induction.

A 15 kDa ribonuclease (RNase) was purified from dried fruiting bodies of the wild edible mushroom Armillaria luteo-virens. The simple 4-step purification protocol involved ion-exchange chromatography on DEAE-cellulose, affinity chromatography on Affi-gel blue gel, ion-exchange chromatography on SP-Sepharose and a final gel filtration by FPLC on Superdex-75. The RNase was unadsorbed on Affi-gel blue gel, but adsorbed on DEAE-cellulose and SP-Sepharose. The N-terminal amino acid sequence of purified RNase was AGVQYKLTILLV, which showed low sequence homology to those of previously reported RNases. The optimal pH and temperature of the enzyme were very close to 4.0 and 70 degrees C, respectively. The enzyme showed considerably high ribonucleolytic activity and broad specificity towards polyhomoribonucleotides, with a specificity of poly(U) > poly(C) > poly (G) > poly(A). The ribonucleolytic activities towards poly(U), poly(C), poly(G) and poly(A) were 279.5, 184.1, 69.9 and 52.3 U/mg, respectively.

Purpose To explore the involvement of N 6 -methyladenosine (m 6 A) modification in circular RNAs (circRNAs) and relevant methyltransferases in the lesion of lens epithelium cells (LECs) under the circumstances of age-related cataract (ARC). Methods LECs were collected from normal subjects and patients with cortical type of ARC (ARCC). M 6 A-tagged circRNAs and circRNAs expression were analyzed by m 6 A-modified RNA immunoprecipitation sequencing (m 6 A-RIP-seq) and RNA sequencing (RNA-seq). Gene Ontology (GO) annotation and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were used to predict possible functions of the m 6 A-circRNAs. Expression of m 6 A-related methyltransferase and demethytransferase was measured by quantitative real-time polymerase chain reaction. Expression and location of AlkB homolog 5 RNA demethylase (ALKBH5), a key component of m 6 A demethytransferase, were determined by Western blot and immunostaining. Results All 4646 m 6 A peaks within circRNAs had different abundances, with 2472 enriched and 2174 subdued. The level of m 6 A abundance in total circRNAs was decreased in the LECs from ARCCs in comparison with the controls. We also found that the expression of highly m6A-tagged circRNAs was mostly decreased in comparison with non-m 6 A-tagged circRNAs. The bioinformatics analysis predicted the potential functions of m 6 A modified circRNAs and the relevant pathways that may be associated with m 6 A modified circRNAs. Among five major methyltransferases, ALKBH5 was significantly upregulated in LECs of ARCCs. Conclusions Our data provided novel evidence regarding the involvement of circRNAs m 6 A modifications in ARC. The altered expression of methyltransferases in lens tissue might selectively change the epigenetic profile of lens genome through regulating genes that host the circRNAs, thus enhance the susceptibility to ARC. The results might provide a new insight in the molecular target of ARC pathogenesis.

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Cinnamaldehyde (CA) is a bioactive compound isolated from the stem bark of Cinnamomum cassia, that has been identified as an antiproliferative substance with pro-apoptotic effects on various cancer cell lines in vitro. In the present study, the effects of CA on human colon cancer cells were investigated at both the molecular and cellular levels. Three types of colorectal cancer cells at various stages of differentiation and invasive ability (SW480, HCT116 and LoVo) were treated with CA at final concentrations of 20, 40 and 80 µg/ml for 24 h. Compared with the control group, the proliferation inhibition rate of the human colorectal cancer cells following treatment with CA increased in a dose- and time-dependent manner. The invasion and adhesion abilities of the cells were significantly inhibited as indicated by Transwell and cell-matrix adhesion assays. Meanwhile, CA also upregulated the expression of E-cadherin and downregulated the expression of matrix metalloproteinase-2 (MMP-2) and MMP-9. CA also elevated the apoptotic rate. The levels of pro-apoptotic genes were upregulated while the levels of apoptosis inhibitory genes were decreased which further confirmed the pro-apoptotic effect of CA. In order to explore the mechanism of CA-induced apoptosis, insulin-like growth factor-1 (IGF-1) and PI3K inhibitor (LY294002) were used to regulate the phosphoinositide 3-kinase (PI3K)/AKT pathway. The transcription activity of PI3K/AKT was markedly inhibited by CA, as well as IGF-1 which functions as an anti-apoptotic factor. In conclusion, CA has the potential to be developed as a new antitumor drug. The mechanisms of action involve the regulation of expression of genes involved in apoptosis, invasion and adhesion via inhibition of the PI3K/Akt signaling pathway.

BackgroundColorectal cancer has become one of the leading cause of cancer morbidity and mortality throughout world. Hederagenin, a derivative of oleanolic acid isolated from the leaves of ivy (Hedera helix L.), has been shown to have potential anti-tumor activity. The study was conducted to evaluate whether hederagenin could induce apoptosis of human colon cancer LoVo cells and explore the possible mechanism.MethodsMTT assay was used for evaluating cell viability while Annexin V-FITC/PI assay and Hoechst 33342 nuclear stainining were used for the determination of apoptosis and mitochondrial membrane potential. DCFH-DA fluorescence staining and flow cytometry were used to measure ROS generation. Real-time PCR and western blot analysis were performed for apoptosis-related protein expressions.ResultsMTT assay showed that hederagenin could significantly inhibit the viability of LoVo cells in a concentration-dependent and time-dependent manner by IC50 of 1.39 μM at 24 h and 1.17 μM at 48 h. The apoptosis ratio was significantly increased to 32.46% and 81.78% by the induction of hederagenin (1 and 2 μM) in Annexin V-FITC/PI assay. Hederagenin could also induce the nuclear changes characteristic of apoptosis by Hoechst 33342 nuclear stainining under fluorescence microscopy. DCFH-DA fluorescence staining and flow cytometry showed that hederagenin could increase significantly ROS generation in LoVo cells. Real-time PCR showed that hederagenin induced the up-regulation of Bax and down-regulation of Bcl-2, Bcl-xL and Survivin. Western blotting analysis showed that hederagenin decreased the expressions of apoptosis-associated proteins Bcl-2, procaspase-9, procaspase-3, and polyADP- ribosepolymerase (PARP) were increased, while the expressions of Bax, caspase-3, caspase-9 were increased. However, there was no significant change on caspase-8.ConclusionsThese results indicated that the disruption of mitochondrial membrane potential might contribute to the apoptosis of hederagenin in LoVo cells. Our findings suggested that hederagenin might be a promising therapeutic candidate for human colon cancer.

Abstract. Gastric cancer (GC) is the third primary cause of cancer-related mortality and one of the most common type of malignant diseases worldwide. Despite remarkable progress in multimodality therapy, advanced GC with high aggressiveness always ends in treatment failure. Epithelialmesenchymal transition (EMT) has been widely recognized to be a key process associating with GC evolution, during which cancer cells go through phenotypic variations and acquire the capability of migration and invasion. Wnt/β-catenin pathway has established itself as an EMT regulative signaling due to its maintenance of epithelial integrity as well as tight adherens junctions while mutations of its components will lead to GC initiation and diffusion. The E-cadherin/β-catenin complex plays an important role in stabilizing β-catenin at cell membrane while disruption of this compound gives rise to nuclear translocation of β-catenin, which accounts for upregulation of EMT biomarkers and unfavorable prognosis. Additionally, several microRNAs positively or negatively modify EMT by reciprocally acting with certain target genes of Wnt/β-catenin pathway in GC. Thus, this review centers on the strong associations between Wnt/β-catenin pathway and microRNAs during alteration of EMT in GC, which may induce advantageous therapeutic strategies for human gastric cancer.