TRIM11, a direct target of miR-24-3p, promotes cell proliferation and inhibits apoptosis in colon cancer.

TRIM11 (tripartite motif-containing protein 11) is an E3 ubiquitin ligase recently identified as an oncogene in malignant glioma and lung cancer. In the present study, we report that expression of TRIM11 was increased in colon cancer (CC) tissue relative to paired normal tissues and that higher TRIM11 levels predicted poor overall survival (OS) and disease-free survival (DFS) in CC patients. Mechanistically, we showed that miR-24-3p downregulation contributes to TRIM11 upregulation in CC. We also demonstrated that TRIM11 overexpression promotes cell proliferation and colony formation and inhibits apoptosis in CC, while knocking down TRIM11 using CRISPR/Cas9-mediated genome editing inhibited cell proliferation and induced apoptosis. Silencing TRIM11 in vivo decreased tumor growth. These findings indicate that TRIM11 facilitates CC progression by promoting cell proliferation and inhibiting apoptosis and that the novel miR-24-3p/TRIM11 axis may be a useful new target for treating patients with CC.

Biological significance of PinX1 telomerase inhibitor in esophageal carcinoma treatment.

In the present study, to investigate the expression of PinX1 gene and its functional effects in human esophageal carcinoma (Eca)-109 cell line, expression vectors of human PinX1 (pEGFP-C3-PinX1) and its small interfering RNA (PinX1-FAM-siRNA) were constructed and transfected into Eca-109 cells using Lipofectamine 2000. Firstly, the mRNA expression level of PinX1 was examined using reverse transcription-polymerase chain reaction (RT-PCR). Once successful transfection was achieved, the effects on the mRNA level of human telomerase reverse transcriptase (hTERT), telomerase activity, cell proliferation and apoptosis were examined by semi-quantitative RT-PCR, stretch PCR, MTT assay and flow cytometry, respectively. Analysis of restriction and sequencing demonstrated that the recombining plasmids were successfully constructed. The results also indicated that transfection with pEGFP-C3-PinX1 and PinX1-FAM-siRNA into Eca-109 cells significantly increased PinX1 mRNA, decreased hTERT mRNA by 29.9% (P<0.05), and significantly reduced telomerase activity (P<0.05), inhibited cell growth, and increased the cell apoptotic index from 19.27±0.76 to 49.73±2%. The transfected PinX1-FAM-SiRNA exhibited PinX1 mRNA expression levels that were significantly decreased by 70% (P<0.05), whereas the remaining characteristics of Eca-109 cells, including cell growth, mRNA level of hTERT, telomerase activity and cell apoptotic index were not altered. Exogenous PinX1 has been demonstrated to be highly expressed in human Eca. PinX1 can inhibit human telomerase activity and the expression of hTERT mRNA, reduce tumor cell growth and induce apoptosis. Notably, these inhibitory functions were inhibited by silencing PinX1 in Eca with PinX1-FAM-siRNA. PinX1 was successfully increased and decreased in the present study, demonstrating that it may be a potential telomerase activity inhibitor. As PinX1 is an endogenous telomerase inhibitor, it may be used as a novel tumor-targeted gene therapy.

Paeoniflorin inhibits doxorubicin-induced cardiomyocyte apoptosis by downregulating microRNA-1 expression.

Doxorubicin (DOX) is an effective anthracycline anti-tumor antibiotic. Because of its cardiotoxicity, the clinical application of DOX is limited. Paeoniflorin (PEF), a monoterpene glucoside extracted from the dry root of Paeonia, is reported to exert multiple beneficial effects on the cardiovascular system. The present study was designed to explore the protective effect of PEF against DOX-induced cardiomyocyte apoptosis and the underlying mechanism. In cultured H9c2 cells, PEF (100 µmol/l) was added for 2 h prior to exposure to DOX (5 µmol/l) for 24 h. Cell viability, creatine kinase activity, cardiomyocyte apoptosis, intracellular reactive oxygen species (ROS) levels, and the expression of microRNA-1 (miR-1) and B-cell lymphoma 2 (Bcl-2) were measured following treatment with PEF and/or DOX. The results showed that treatment with DOX notably induced cardiomyocyte apoptosis, concomitantly with enhanced ROS generation, upregulated miR-1 expression and downregulated Bcl-2 expression. These effects of DOX were significantly inhibited by pretreatment of the cells with PEF. These results suggest that the inhibitory effect of PEF on DOX-induced cardiomyocyte apoptosis may be associated with downregulation of miR-1 expression via a reduction in ROS generation.

Picroside II protects myocardium from ischemia/reperfusion-induced injury through inhibition of the inflammatory response.

The inflammatory response is important in the pathogenesis of myocardial ischemia/reperfusion (I/R) injury. Picroside II, the primary active constituent of Picrorhizae, has been reported to protect the myocardium from I/R-induced injury, however, the exact mechanism underlying these protective effects remains unclear. The aim of the present study was to investigate the mechanism underlying the protective effects of picroside II on I/R-induced myocardial injury. Adult male Sprague-Dawley rats underwent 1 h left coronary artery occlusion followed by 3 h reperfusion. Picroside II was administered (10 mg/kg) via the tail vein 30 min prior to left coronary artery occlusion. The results revealed that pretreatment of picroside II could significantly alleviate I/R-induced myocardial injury concomitantly with a decrease in inflammatory factor production. In addition, picroside II was also able to decrease high mobility group box 1 (HMGB1) expression, and release and downregulate the expression of the receptor for advanced glycation end products (RAGE), toll-like receptor (TLR)-2 and TLR-4. Furthermore, picroside II was able to inhibit nuclear factor-κB (NF-κB) activation. The results indicated that the protective effect of picroside II on I/R-induced myocardial injury was associated, at least partly, with inhibition of the inflammatory response by suppressing the HMGB1-RAGE/TLR-2/TLR-4-NF-κB signaling pathway.

Therapeutic effect and apoptosis mechanism of lung-tonifying and expectorant decoction on lung cancer rats with Qi deficiency and blood stasis.

OBJECTIVE: To explore the effect and specific mechanism of lung-tonifying and expectorant decoction on lung cancer rats with Qi deficiency and blood stasis, and aim to provide a new idea on treating the disease with traditional Chinese medicine based on syndrome differentiation. METHODS: A total of 60 C57BL/6J male rats were included in the study. The model of Qi deficiency and blood stasis was established in 60 rats by using multiple-factor stimulation. About 10 rats were randomly taken to verify whether the model establishment was successful and the rest of 50 rats were divided into 5 groups with 10 rats each: blank control group, cisplatin group, low dose group, medium dose group and high dose group. The blank control group was treated with normal saline, and cisplatin group was treated with cisplatin while the other three groups were treated with lung-tonifying and expectorant decoction at different doses. The volume change in transplanted tumor, tumor inhibition rate, apoptosis rate, and expression of Bcl-2, Bax, cleaved caspase-3 and cleaved caspase-9 in 5 groups were compared. RESULTS: The rapidest growth rate of transplanted tumor volume was observed in blank control group and the slowest in cisplatin group. The growth rate was gradually decreased with the increasing dose of lung-tonifying and expectorant decoction, and the difference in growth of tumor volume among groups was statistically significant (P < 0.05). The cisplatin group showed the highest tumor inhibition rate, with dose-dependent increase (P < 0.05). The apoptosis rate in low dose group was higher than blank control group but lower than high dose group (P < 0.05). The apoptosis rate in medium dose group was significantly higher than blank control group (P < 0.05). The apoptosis rate in high dose group was significantly higher than control group (P < 0.05). The positive expression rates of Bcl-2 and Bax in all groups showed statistically significant difference (P < 0.05), while expression of cleaved caspase-3 and cleaved caspase-9 in 5 groups was significantly different, with dose-dependent increase (P < 0.05). CONCLUSIONS: The lung-tonifying and expectorant decoction inhibits the proliferation of tumor cells by inducing and activating the cell apoptosis in treatment of lung cancer with Qi deficiency and blood stasis, probably with good clinical therapeutic effect.

Picroside â ¡ inhibits hypoxia/reoxygenation-induced cardiomyocyte apoptosis by ameliorating mitochondrial function through a mechanism involving a decrease in reactive oxygen species production.

Reactive oxygen species (ROS)­induced mitochondrial dysfunction plays an important role in cardiomyocyte apoptosis during myocardial ischemia/reperfusion (I/R) injury. Picroside Ⅱ, isolated from Picrorhiza scrophulariiflora Pennell (Scrophulariaceae), has been reported to protect cardiomyocytes from hypoxia/reoxygenation (H/R)­induced apoptosis, but the exact mechanism is not fully clear. The aim of the present study was to explore the protective effects of picroside Ⅱ on H/R­induced cardiomyocyte apoptosis and the underlying mechanism. In the H9c2 rat cardiomyocyte cell line, picroside Ⅱ (100 µg/ml) was added for 48 h prior to H/R. The results showed that picroside Ⅱ markedly inhibited H/R­induced cardiomyocyte apoptosis. In addition, picroside Ⅱ was also able to decrease the opening degree of mitochondrial permeability transition pore (mPTP), increase the mitochondrial membrane potential, inhibit cytochrome c release from mitochondria to cytosol and downregulate caspase­3 expression and activity concomitantly with the decreased ROS production. These results suggested that picroside Ⅱ inhibited H/R­induced cardiomyocyte apoptosis by ameliorating mitochondrial function through a mechanism involving a decrease in ROS production.

Anticancer effect of salidroside on A549 lung cancer cells through inhibition of oxidative stress and phospho-p38 expression.

Oxidative stress is important in carcinogenesis and metastasis. Salidroside, a phenylpropanoid glycoside isolated from Rhodiola rosea L., shows potent antioxidant properties. The aim of the present study was to investigate the roles of salidroside in cell proliferation, the cell cycle, apoptosis, invasion and epithelial-mesenchymal transition (EMT) in A549 cells. The human alveolar adenocarcinoma cell line, A549, was incubated with various concentrations of salidroside (0, 1, 5, 10 and 20 µg/ml) and cell proliferation was detected by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Propidium iodide (PI) staining was used to determine the cell cycle by flow cytometry. Cell apoptosis was detected by Annexin V-fluorescein isothiocyanate and PI double-staining, and tumor invasion was detected by Boyden chamber invasion assay. Western blot analysis was performed to detect the expression of EMT markers, Snail and phospho-p38. The results showed that salidroside significantly reduced the proliferation of A549 cells, inhibited cell cycle arrest in the G0/G1 phase and induced apoptosis. Salidroside inhibited transforming growth factor-ß-induced tumor invasion and suppressed the protein expression of Snail. As an antioxidant, salidroside inhibited the intracellular reactive oxygen species (ROS) formation in a dose-dependent manner in A549 cells, and depletion of intracellular ROS by vitamin C suppressed apoptosis by salidroside treatment. Salidroside was also found to inhibit the expression of phospho-p38 in A549 cells. In conclusion, salidroside inhibits cell proliferation, the cell cycle and metastasis and induces apoptosis, which may be due to its interference in the intracellular ROS generation, thereby, downregulating the ROS-phospho-p38 signaling pathway.

Inhibitory effects of paeoniflorin on lysophosphatidylcholine-induced inflammatory factor production in human umbilical vein endothelial cells.

Lysophosphatidylcholine (LPC) plays an important role in atherosclerosis through initiation of endothelial inflammation response. Paeoniflorin (PEF), isolated from the dry root of Paeonia, has been reported to exert an anti-inflammatory effect, but the exact mechanism is not fully understood. The aim of this study was to investigate the inhibitory effects of PEF on LPC-induced inflammatory factor production and the underlying mechanisms. In human umbilical vein endothelial cells (HUVECs), different concentrations (1, 10 or 100 µmol/l) of PEF were added 2 h prior to exposure to LPC (10 mg/l) for 24 h. The results showed that PEF significantly inhibited LPC-induced inflammatory factor production. In addition, PEF was also able to suppress the enhanced high mobility group box-1 (HMGB1) expression and release, upregulated expression of receptor for advanced glycation end product (RAGE), Toll-like receptor (TLR)-2 and TLR-4, and increased nuclear factor-κB (NF-κB) activity induced by LPC. Our results suggest that PEF suppresses LPC-induced inflammatory factor production through inhibition of the HMGB1-RAGE/TLR-2/TLR-4-NF-κB pathway.

Paeoniflorin protects myocardial cell from doxorubicin-induced apoptosis through inhibition of NADPH oxidase.

Increased intracellular reactive oxygen species (ROS) are involved in doxorubicin (DOX)-induced myocardial cell apoptosis, and paeoniflorin (PEF) has been shown to exert an antioxidant effect. The aim of the present study was to explore the protective effect of PEF on DOX-induced myocardial cell apoptosis and the underlying mechanisms. In cultured H9c2 cells, different concentrations (1, 10, or 100 µmol/L) of PEF was added for 2 h prior to exposure to DOX (5 µmol/L) for 24 h. Cell apoptosis was evaluated by hoechst 33342 staining, and caspase-3 expression and activity. The mRNA and protein expression of NADPH oxidase (NOX) 2 and NOX4 was determined by real-time polymerase chain reaction and Western blot, respectively. Intracellular ROS and NOX activity were measured by assay kit. The results showed that DOX significantly increased myocardial cell apoptosis, increased caspase-3 expression and activity concomitantly with enhanced ROS production, and increased NOX2, NOX4 mRNA and protein expression, and NOX activity. These effects were remarkably inhibited by pretreatment of PEF. Our results suggested that PEF has a protective effect against DOX-induced myocardial cell apoptosis through a mechanism involving a decrease in ROS production by inhibition of NOX2, NOX4 expression, and NOX activity.

Reversal of isoprenaline-induced cardiac remodeling by rutaecarpine via stimulation of calcitonin gene-related peptide production.

Dysfunction of capsaicin-sensitive sensory nerves is involved in cardiac remodeling, and rutaecarpine has been shown to exert a beneficial effect on cardiac function through activating the sensory nerves. This study was conducted to explore the potential inhibitory effect of rutaecarpine on cardiac remodeling and the underlying mechanisms. A rat cardiac remodeling model was established by injection of isoprenaline (5 mg/kg per day, s.c.) for 10 days. Rutaecarpine (10 or 40 mg/kg, i.g.) was coadministrated with isoprenaline to evaluate the effect of rutaecarpine on cardiac remodeling. After echocardiographic analysis was performed, blood samples were collected to quantify calcitonin gene-related peptide (CGRP), dorsal root ganglia were isolated for examining CGRP mRNA expression, and the hearts were weighed and saved for evaluating the parameters related to apoptosis and hypertrophy. Isoprenaline significantly increased the ratio of left ventricle weight to body weight, the cross-sectional area of cardiomyocytes, cardiac apoptosis, and collagen deposition concomitantly with decreased CGRP production, which were reversed by rutaecarpine treatment. The beneficial effects of rutaecarpine were attenuated by pretreatment with capsaicin, which selectively depleted CGRP. These results suggest that rutaecarpine was able to reverse isoprenaline-induced cardiac remodeling through stimulating CGRP production.