Upregulated expression of ACTL8 contributes to invasion and metastasis and indicates poor prognosis in colorectal cancer.

BACKGROUND: ACTL8 is a member of the CT antigens. There are only few studies on the role of ACTL8 in malignant tumors. The aim of this study is to investigate the expression and clinical significance of ACTL8 protein in colorectal cancer (CRC). MATERIALS AND METHODS: Human CRC tissues and cell lines, and paired adjacent non-tumor tissues and human intestinal epithelial cell lines were obtained to evaluate the expression of ACTL8. The association between protein expression of ACTL8 and clinicopathological parameters and prognosis of CRC patients was examined. The biological functions of ACTL8 in the invasion and metastasis of CRC were determined by wound healing and transwell invasion assays after silencing of ACTL8 in CRC cell lines. The potential target genes of ACTL8 were also identified by quantitative reverse transcription PCR and Western blotting after silencing of ACTL8 in CRC cell lines. RESULTS: It was found that ACTL8 was upregulated in human CRC tissues and cell lines. The expression of ACTL8 was positively associated with poor differentiation, invasion and metastasis, postoperative infection, and poor prognosis, but negatively associated with proximal margin length. In addition, silencing of ACTL8 significantly decreased the capacity of invasion and migration in HT29 and SW620 CRC cell lines. Moreover, silencing of ACTL8 significantly decreased the expression of TRIM29 in HT29 and SW620 CRC cell lines. CONCLUSION: These results suggest that ACTL8 plays a key role in the invasion and metastasis of CRC, and TRIM29 may be involved in the ACTL8-mediated poor prognosis of CRC.

[Research on EGCG improving the degenerative changes of the brain in AD model mice induced with chemical drugs].

OBJECTIVE: To study the effect and mechanism of (-)-Epigallocatechin-3-gallate (EGCG) on the degeneretive changes of the brain in Alzheimer's disease (AD) model mice induced with chemical drugs. METHODS: AD model mice were established by subcutaneously injecting with 3% D-gal at the dose of 150 mg/kg body weight once daily for 6 weeks. From the third week, the mice of D-gal + V(E) 280 U/kg group, D-gal + EGCG 2 mg/(kg x d) group and D-gal + EGCG 6 mg/(kg x d) group were intragastricly given with 5.6% V(E) at the dose of 280 IU/kg and EGCG at the dose of 2 mg/kg x d or 6 mg/kg x d respectively after injection of D-gal. The mice of control group, D-gal + dd H2O group and D-gal + oil group were administered with same volume vehicle distilled water and soybean oil respectively. The pathological changes of the brain in AD model mice were observed by HE staining analysis, the immunohistochemical analysis of beta-amyloid (Abeta) and evaluating the expression of amyloid precursor protein (APP) in the hippocampus of mice by Western blot analysis. RESULTS: EGCG 2 mg/(kg x d) or 6 mg/(kg x d) 4 weeks, ig evidently released neuronal injury in the hippocampus of the AD mice induced by D-gal, and significantly reduced the express of Abeta and APP in the hippocampus of AD model mice induced by D-gal (P < 0.01). CONCLUSION: EGCG has a protective effect on AD model mice induced by D-gal by decreasing the expression of APP and beta-Amyloid in the hippocampus of mice.

Neuroprotective effects of (-)-epigallocatechin-3-gallate on aging mice induced by D-galactose.

The aim of the present study was to investigate the protective effects of (-)-epigallocatechin-3-gallate (EGCG), the main polyphenolic constituent of green tea, in aging mice induced by D-galactose (D-gal). The aging mice model was induced by subcutaneous (s.c.) injection of D-gal (150 mg/kg) once daily for 6 weeks. EGCG (2 mg/kg or 6 mg/kg) was administered intragastrically (i.g.) once daily for 4 weeks after 2-week D-gal injection. The water maze test was used to evaluate the learning and memory function of mice. The activities of total superoxide dismutase (T-SOD) and glutathione peroxidase (GSH-Px) and the contents of malondialdehyde (MDA) in the hippocampus were measured using different biochemical kits to estimate the changes in the antioxidative ability of mice. TdT-mediated dUTP-biotin nick end labeling (TUNEL) staining method was used to detect neuronal apoptosis, and the activation and expression of proapoptotic protein caspase-3 in the hippocampus were observed and analyzed using immunohistochemical staining and the Western blot method to evaluate apoptosis in the brain. The results indicated that subcutaneous injection of D-gal induced learning and memory impairment in mice, decreased T-SOD and GSH-Px activities, increased MDA contents in the hippocampus, and increased the cell apoptosis index and cleaved caspase-3 protein expression in the hippocampus. Oral administration of EGCG (2 mg/kg or 6 mg/kg) for 4 weeks significantly improved the cognitive deficits in mice and elevated T-SOD and GSH-Px activities, decreased MDA contents in the hippocampus, and reduced the cell apoptosis index and expression of cleaved caspase-3 in the mouse hippocampus. The results suggest that EGCG has potent neuroprotective effects on aging mice induced by D-gal through antioxidative and antiapoptotic mechanisms, indicating that EGCG is worthy of further study in aging.