Calunduloside E inhibits HepG2 cell proliferation and migration via p38/JNK-HMGB1 signalling axis.

High-mobility group box 1 (HMGB1), a highly conserved chromosome protein, is considered as a potential therapeutic target and novel biomarker because of its regulation in the proliferation and metastasis of Hepatocellular carcinoma (HCC). Calenduloside E (CE), a natural active product, has been reported to anti-cancer effect. However, the role and underlying molecular mechanism of CE in HCC is still unclear. The purpose of this study is to investigate the effects of CE on the proliferation and migration of HCC, and then explore the possible underlying molecular mechanism. HepG2 cells were treated with CE or transfected with HMGB1 shRNA plasmids, EdU and colony formation assays were used to detect cell proliferation ability. Wound healing and transwell assays were used to determine the role of CE in cell migration. The expression of Cyclins, PCNA, MMPs, HMGB1, N-cadherin, E-cadherin and phosphorylation of p38, ERK and JNK were all detected using Western blotting. Our results showed that CE inhibited HepG2 cells proliferation and migration in a dose dependent manner; reduced the expression levels of Cycins, PCNA, HMGB1, MMPs and N-cadherin; up-regulated E-cadherin expression; enhanced the phosphorylation of p38 and JNK signalling pathways. Blocking the activation of p38 and JNK obviously reversed CE-mediated inhibitory effects on HepG2 cell proliferation and migration; reversed CE-induced down-regulation of Cyclins, PCNA, MMPs, N-cadherin and HMGB1, as well as E-cadherin up-regulation. In conclusion, our study suggested that CE reduces the expression levels of Cyclins, MMPs and epithelial-mesenchymal transformation (EMT) through p38/JNK-HMGB1 signaling axis and then inhibits HepG2 cells proliferation and migration in HepG2 cells. This study provides a new perspective for the anti-tumour molecular mechanism of CE in HCC.

Salidroside attenuates inflammatory response via suppressing JAK2-STAT3 pathway activation and preventing STAT3 transfer into nucleus.

Salidroside (SAL) is an active ingredient isolated from the Rhodiola rosea, has potent anti-inflammatory effect, but the mechanism is still elusive. The purpose of this study is to verify the effects of SAL on LPS-induced inflammatory response and investigate the possible underlying molecular mechanism. RAW264.7 cells were pre-incubated with SAL for 2h, then stimulated with or without LPS for another 16h. The levels of TNF-α, MCP-1, IL-6, and PGE2 were detected by ELISA, and the production of NO was determined by nitrite analysis. The expression levels of nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) were detected by Western blotting. In RAW264.7 cells and murine peritoneal macrophages, the activation of signal molecules was also measured by Western blot. The nuclear translocation of STAT3 was determined by Laser confocal and nucleocytoplasmic separation experiments. Our results showed that SAL attenuated the productions of TNF-α, IL-6, MCP-1, PGE2 and NO dose dependently. SAL also suppressed LPS-induced expressions of iNOS and COX-2 significantly. Further studies revealed that SAL down-regulated the phosphorylation of JAK2-STAT3 signaling pathway and reduced the nuclear translocation of STAT3 induced by LPS in RAW264.7 cells and primary peritoneal macrophages. In addition, consistent with the results in vitro, in the model of mice acute lung injury (ALI) induced by LPS, SAL reduced the infiltration of inflammatory cells and decreased the levels of serum TNF-α and IL-6 obviously. Taken together, these data indicated that SAL exerted anti-inflammatory action via down-regulating LPS-induced activation of JAK2-STAT3 pathway and suppressing STAT3 transfer into the nucleus at least in part.

[Effect of sodium aescinate in inducing human breast cancer MCF-7 cells apoptosis by inhibiting AKT, ERK and upstream signal SRC activity].

To study the effect of sodium aescinate in inducing human breast cancer MCF-7 cells apoptosis and its possible mechanism. MTT assay was used to detect the inhibitory effect of sodium aescinate on the proliferation of MCF-7 cells. The morphological changes were observed under inverted microscope. DAPI nuclear staining was used to detect the changes in cell nucleus. Annexin V-FITC/PI flow cytometry was adopted to test the apoptosis rate. Changes in apoptosis-related proteins (PARP, cleaved caspase-8 and pro-caspase-3), cell survival-associated signal molecules (AKT and ERK) and their common upstream kinase SRC was detected by Western blotting. The result showed that after different concentrations of sodium aescinate were used to treat breast cancer MCF-7 cells, they inhibited the proliferation of MCF-7 cells in a dose-dependent manner, induced cell apoptosis (typical morphological changes in nucleus, significant increase in cell apoptosis rate). The expressions of cleaved PARP and caspase-8 increased, while the expression of pro-caspase-3 decreased, which further verified sodium aescinate's effect in inducing cell apoptosis. Sodium aescinate significantly inhibited the phosphorylation of cell survival-related signal molecules (AKT, ERK) and down-regulate the activation of their common up-stream kinase SRC. The findings indicated that sodium aescinate can block signals transiting to downstream molecules AKT, ERK, inhibit the proliferation of breast cancer cell MCF-7 cell apoptosis and induced cell apoptosis by suppressing the activation of SRC.