[Protective effect of ginsenoside Rg1 again PC-12 cells in OGD injury through mTOR/Akt/FoxO3 signaling pathway].

OBJECTIVE: To investigate the protective effect of ginsenoside Rg1 on oxygen-glucose deprivation (OGD) in PC-12 cells, and preliminarily discuss the potential molecular mechanism of mTOR/Akt/FoxO3 signaling pathway. METHOD: The OGD PC-12 cell model was established. The cell viability was measured by MTT assay. After the pretreatment with Rg1 with the concentration of 10, 20, 40 micromol x L(-1) for 24 h, the cell viability was observed. Lactate dehydrogenase (LDH) release, superoxide dismutase (SOD) ac- tivity and malondialdehyde (MDA) level were detected by colorimetry assay. mTOR, p-Akt(ser473), p-Akt(tjr308), Akt, p-FoxO3, FoxO3 in cytoplasm and nucleus, and total FoxO3 protein expression were detected by Western blot assay. RESULT: OGD could significantly in- hibit cell proliferation in 4-24 h in a time-dependent manner. After pretreatment for 24 h, Rg1 (20, 40 micromol x L(-1)) could notably elevate the cell viability and SOD viability and reduce the LDH release and MDA content. Besides, Rg1 also inhibited OGD-induced mTOR and p-Akt(ser473) decreases. After treatment for 6 h, OGD could reduce FoxO3 phosphorylation and promote FoxO3 in cytoplasm. This data suggested that Rg1 could protect PC-12 cell injury through mTOR/p-Akt/FoxO3 signaling pathway. CONCLUSION: Ginsenoside Rg1 could attenuate OGD-induced PC-12 cell injury. Its action mechanism may be closely related to activation of mTOR/p-Akt/FoxO3 signaling pathway.

L1, ß-catenin, and E-cadherin expression in patients with colorectal cancer: correlation with clinicopathologic features and its prognostic significance.

OBJECTIVE: Currently, there are no clinically used/routine biomarkers that accurately predict whether colorectal cancer (CRC) patients will or will not respond to adjuvant chemotherapy. The aim of this study was to investigate L1, ß-catenin, and E-cadherin expression in patients with CRC and their relationship to tumor progression, and to identify patients who will respond to chemotherapy. METHODS: A total of 142 patients who underwent surgical treatment for CRC were chosen retrospectively. The samples from these patients were analyzed by immunohistochemistry. SPSS-14 program package was used for statistical calculation. RESULTS: Expression of L1, ß-catenin, and E-cadherin were found to be strongly associated with invasion and metastasis of CRC. Cox multivariate analysis results indicated that L1 expression and stage of Dukes could be considered as the independent prognostic factors for survival. Furthermore, our study found that the 5-year survival rate was the significantly associated with the expression of L1, ß-catenin (normal and ectopic expression), and E-cadherin for Dukes' stage B (P < 0.01) patients. However, no such result was found for Dukes' stage A (P > 0.05) and C (P > 0.05) patients. CONCLUSION: Our study provided reference for identifying patients who need adjuvant chemotherapy. L1, ß-catenin, and E-cadherin could be considered as biomarkers to predict whether CRC patients will or will not respond to adjuvant chemotherapy.

L1CAM is involved in lymph node metastasis via ERK1/2 signaling in colorectal cancer.

L1-cell adhesion molecule (L1CAM, L1) belongs to the immunoglobulin superfamily and was originally found to play a role in nerve cells. Recently, the expression and prognostic value of L1 has been established in several cancers, including colorectal cancer (CRC). However, its association with lymph node metastasis in CRC and the mechanisms underlying its effects remain unclear. In this study, we evaluated the L1 transcript levels in CRC (n=12) and normal intestinal tissues (n=15) by qRT-PCR. Western blotting was used to evaluate L1 and pERK1/2 expression levels. Immunohistochemistry was performed to evaluate the relationship between L1 and pERK1/2 in CRC tissues with different levels of differentiation. The mRNA expression levels in CRC tissues were significantly higher compared to normal intestinal tissues. Western blotting demonstrated that both L1 and pERK1/2 levels were higher in CRC than in normal tissues. Immunohistochemistry confirmed that L1 and pERK1/2 levels in adenomas with lymph node metastasis were significantly higher than in poorly and well-differentiated adenomas, indicating that L1 and pERK1/2 levels correlated with CRC lymph node metastasis. In conclusion, L1 and pERK1/2 were significantly up-regulated in CRC tissues and lymph node metastasis may occur via the L1CAM-mediated ERK pathway in CRC.

Hydroxychloroquine potentiates the anti-cancer effect of bevacizumab on glioblastoma via the inhibition of autophagy.

Bevacizumab (BEV) is widely used for the treatment of patients with recurrent glioblastoma (GBM), but recent evidence demonstrated that BEV induced cytoprotective autophagy, which allows tumor cells to survive. Hydroxychloroquine (HCQ) inhibits lysosomal acidification and blocks autophagy via influencing autophagosome fusion and degradation. HCQ is often used to enhance the efficacy of chemoradiotherapy. However, whether HCQ sensitizes GBM cells to BEV and the molecular mechanism of this effect are not clear. We showed that high concentrations of BEV increased the LC3-II/LC3-I ratio and caused the degradation of Beclin1 in the LN18 and LN229 cell lines, indicating that high concentrations of BEV induced the autophagy of the LN18 and LN229 cells. However, BEV (100 µg/ml) did not influence the autophagy of the LN18 and LN229 cells, and HCQ at less than 5 µg/ml significantly accumulated LC3B-II and p62 proteins and blocked the autophagy process. Importantly, we found that HCQ (5 µg/ml) potentiated the anti-cancer effect of BEV (100 µg/ml). Therefore, HCQ is a novel strategy that may augment the efficacy of BEV for GBM via the inhibition of autophagy.

Enhanced absorption of hydroxysafflor yellow A using a self-double-emulsifying drug delivery system: in vitro and in vivo studies.

Hydroxysafflor yellow A (HSYA), the main active ingredient of the safflower plant (Carthamus tinctorius L.), is a hydrophilic drug with low oral bioavailability. Water-in-oil-in-water (w/o/w) double emulsions may enhance the oral absorption of HSYA. In this study, we prepared a self-double-emulsifying drug delivery system (SDEDDS) to improve the absorption of HSYA. SDEDDS consists of water in oil emulsions and hydrophilic surfactants that can self-emulsify into w/o/w double emulsions in the aqueous gastrointestinal environment. Confocal laser scanning micrographs showed that spherical droplets were uniformly distributed in the dispersion medium with narrow particle size distribution and could form fine w/o/w double emulsions upon dilution in dispersion medium with gentle stirring. The dispersed oil droplets contained small dispersed aqueous droplets consistent with the characteristics of double emulsions. Furthermore, in vitro cellular experiments were performed to study the mechanism of the absorption promoting effect of SDEDDS. The accumulation of rhodamine-123 in Caco-2 cells was used to evaluate the efflux transport of p-glycoprotein inhibitor. Histopathologic studies on the rat intestine showed that SDEDDS can cause mucosal damage to a certain degree of toxicity, however this was not serious. These results suggest that SDEDDS can greatly improve the oral absorption of HSYA. Given the toxicity demonstrated to the small intestine, the formulation prescription should be improved to enhance security in the future.