Downregulation of CLDN6 inhibits cell proliferation, migration, and invasion via regulating EGFR/AKT/mTOR signalling pathway in hepatocellular carcinoma.

Accumulating evidence showed that the claudin-6 (CLDN6) expression was abnormal in many cancers, while its expression and biological functions in hepatocellular carcinoma (HCC) is still unclear. The present study demonstrated that CLDN6 was upregulated in HCC tissues compared with tumour-adjacent tissues. CLDN6 silencing was significantly inhibited proliferation, migration, and invasion of HepG2 cells. Meanwhile, downregulation of CLDN6 remarkably inhibited the activation of EGFR/AKT/mTOR signalling pathway. Interestingly, the effect of CLDN6 overexpression on HepG2 cell proliferation and invasion could be inhibited by EGFR/AKT/mTOR signalling pathway inhibitor (AG1478). SIGNIFICANCE OF THE STUDY: These findings suggested that CLDN6 may act as an oncogene in HCC and improve HepG2 cell proliferation, migration, and invasion may via EGFR/AKT/mTOR signalling pathway.

Effects of swimming on pain and inflammatory factors in rats with lumbar disc herniation.

The aim of the present study was to identify the effect of swimming on nerve root pain in rats with lumbar disc herniation (LDH). A total of 72 male Sprague Dawley rats (215±15 g) were randomly divided into three groups (n=24/group): The sham operation, model and exercise intervention groups, with the latter undergoing 4 weeks of swimming training. On days 0, 7, 14 and 28 following surgery, the changes in the post-limb mechanical claw threshold, the phospholipase A2 (PLA2), interleukin (IL)-6 and tumor necrosis factor (TNF)-α mRNA expression levels, the secretory PLA2 (sPLA2) expression, the IL-6 and TNF-α content, the nuclear factor (NF)-κBp65 protein expression level in the nucleus pulposus, and the apoptotic rate of the nucleus pulposus cells were detected. The results demonstrated that, in the model group, the threshold of hind paw withdrawal was decreased, and that the sPLA2 expression, IL-6 and TNF-α content, PLA2, IL-6 and TNF-α mRNA and NF-κBp65 protein expression levels in the nucleus pulposus were increased. The apoptotic rate of the nucleus pulposus cells was increased from day 7 following surgery, as compared with the sham operation group. In the exercise intervention group, the hind paw withdrawal threshold increased and the TNF-α and IL-6 content, sPLA2 expression and PLA2, IL-6 and TNF-α mRNA and NF-κBp65 protein expression levels were decreased from day 14 following surgery, and the apoptotic nucleus pulposus cells were decreased from day 7 following surgery, as compared with the model group. Collectively, the present data suggest that swimming can significantly reduce nerve root pain and inhibit inflammatory reaction in LDH, which can have positive effects on the treatment of LDH.

Lycorine Induces Apoptosis of A549 Cells via AMPK-Mammalian Target of Rapamycin (mTOR)-S6K Signaling Pathway.

BACKGROUND This study was designed to investigate the effect of lycorine (LY) on the AMPK-mTOR-S6K signaling pathway and to clarify its role in autophagy and apoptosis. MATERIAL AND METHODS Various concentrations of LY were used to treat non-small cell lung carcinoma A549 cells. The MTT assay was used to measure cell viability and acridine orange staining was used to detect cell morphology changes. Western blot analysis was used to test the effect of LY on the expression levels of LC3, caspase 3, and other proteins involved in the AMPK-mTOR-S6K signaling pathway. RESULTS The half maximal inhibitory concentration (IC50) of LY after 24-h treatment was 8.5 µM, with stronger inhibitory effect of 24-h LY treatment over 12-h LY treatment. Morphological observation showed that lower doses (4 µM and 8 µM) of LY treatment induced A549 cell death mainly caused by autophagy, whereas the higher dose (16 µM) of LY treatment induced A549 cell death, mainly caused by apoptosis. Furthermore, 8 µM LY caused the highest conversion of LC3-II from LC3-I. All LY treatments activated caspase-3. LY treatment also promoted AMPK phosphorylation (Thr172) and inhibited the phosphorylation of mTOR and S6K. CONCLUSIONS LY induced apoptosis of A549 cells by regulating the AMPK-mTOR-S6K signaling pathway. Lower levels (4~8 µM) of LY-induced autophagy contributed to LY-induced apoptosis.

Effect of pterostilbene on glioma cells and related mechanisms.

Neuroglioma is the most common primary malignant tumor in neurosurgery. Due to unfavorable life quality of patients, the treatment of glioma is a major challenge in clinics. The search for effect treatment drugs thus benefits patient prognosis. As one derivative of resveratrol, pterostilbene has a wide spectrum of pharmaceutical functions, especially with the anti-tumor effects. This study thus investigated the effect of pterostilbene on neuroglioma and related mechanisms. U87 glioma cell line was divided into control, normal culture and different dosages of pterostilbene groups, which received 5 mM or 10 mM pterostilbene for 48 h. MTT assay was used to detect U87 cell proliferation, while invasion assay was employed to test the effect of pterostilbene on cell invasion, followed by flow cytometry assay for analyzing U87 cell apoptosis. Real-time PCR was used to test mRNA expression of Bcl-2 and Bax in glioma cells under the effect of pterostilbene, while Western blotting was used to detect alternation of Bcl-2 and Bax protein levels. Pterostilbene significantly inhibited proliferation and invasion abilities of glioma cells compared to those in control group (P<0.05). It can also enhance cell apoptosis, decrease mRNA and protein of Bcl-2 expression, and increase mRNA and protein expressions of Bax (P<0.05 compared to control group) in a dose-dependent manner. Pterostilbene can facilitate apoptosis of glioma cells, and inhibit their proliferation and invasion via mediating apoptotic/anti-apoptotic homeostasis.