Combination therapy of Juzentaihoto and mesenchymal stem cells attenuates liver damage and regresses fibrosis in mice.

BACKGROUND: Liver cirrhosis is an end-stage multiple liver disease. Mesenchymal stem cells (MSCs) are an attractive cell source for reducing liver damage and regressing fibrosis; additional therapies accompanying MSCs can potentially enhance their therapeutic effects. Kampo medicines exhibit anti-inflammatory and anti-oxidative effects. Here, we investigated the therapeutic effect of MSCs combined with the Kampo medicine Juzentaihoto (JTT) as a combination therapy in a carbon tetrachloride (CCl4)-induced cirrhosis mouse model. METHODS: C57BL/6 mice were administered JTT (orally) and/or MSCs (one time, intravenously). The levels of liver proteins were measured in the sera. Sirius Red staining and hydroxyproline quantitation of hepatic tissues and immune cells were conducted, and their associated properties were evaluated. Liver metabolomics of liver tissues was performed. RESULTS: JTT monotherapy attenuated liver damage and increased serum albumin level, but it did not effectively induce fibrolysis. JTT rapidly reduced liver damage, in a dose-dependent manner, after a single-dose CCl4 administration. Furthermore, JTT-MSC combination therapy attenuated liver damage, improved liver function, and regressed liver fibrosis. The combination increased the CD4+/CD8+ ratio. JTT had stronger effects on NK and regulatory T cell induction, whereas MSCs more strongly induced anti-inflammatory macrophages. The combination therapy further induced anti-inflammatory macrophages. JTT normalized lipid mediators, and tricarboxylic acid cycle- and urea cycle-related mediators effectively. CONCLUSIONS: The addition of JTT enhanced the therapeutic effects of MSCs; this combination could be a potential treatment option for cirrhosis.

Valproic acid overcomes transforming growth factor-ß-mediated sorafenib resistance in hepatocellular carcinoma.

Sorafenib is a multi-kinase inhibitor approved for hepatocellular carcinoma, but rarely causes tumor regression in patients with chronic liver diseases. To investigate whether growth factor-mediated signaling is involved in sorafenib resistance, HepG2 and PLC/PRF/5 hepatoma cells were exposed to epidermal growth factor (EGF), hepatocyte growth factor (HGF) or transforming growth factor-ß (TGF-ß) prior to treatment with sorafenib. Furthermore, to identify an effective combination treatment with sorafenib, growth factor-sensitized cells were treated with sorafenib alone or in combination with celecoxib, lovastatin or valproic acid (VPA). Trypan blue staining and Annexin V assays showed that the cytotoxic effect of sorafenib was inhibited by 15-54% in cells sensitized to TGF-ß (P<0.05). Western blotting analysis showed that TGF-ß significantly activated extracellular signal-regulated kinase (ERK)-mediated AKT signaling, and sorafenib failed to suppress both ERK and AKT in TGF-ß-sensitized cells. The decreased anti-tumor effect of sorafenib was rescued by chemical inhibition of ERK and AKT. When TGF-ß-sensitized cells were treated with sorafenib plus VPA, the levels of phosphorylated ERK and AKT were considerably suppressed and the numbers of dead cells were increased by 3.7-5.7-fold compared with those exposed to sorafenib alone (P<0.05). Moreover, low dose sorafenib-induced cell migration was effectively suppressed by combination treatment with sorafenib and VPA. Collectively, TGF-ß/ERK/AKT signaling might play a critical role in sorafenib resistance in hepatoma cells, and combination treatment with VPA may be effective against this drug resistance.

Blockade of ataxia telangiectasia mutated sensitizes hepatoma cell lines to sorafenib by interfering with Akt signaling.

Sorafenib is a multi-kinase inhibitor applicable to hepatocellular carcinoma (HCC), but its limited therapeutic effects are a major problem to be solved. Here, we show that blockade of ataxia telangiectasia mutated (ATM) improves the antitumor effects of sorafenib. When hepatoma cell lines HepG2 and PLC/PRF/5 were treated with sorafenib plus ATM small inhibitory RNAs, ATM inhibitor KU55933 or caffeine, Akt signaling was suppressed and the cytotoxic effects were significantly potentiated. Moreover, ATM inhibition effectively suppressed the sorafenib-induced cell migration. Taken together, manipulation of ATM activity might be a useful strategy for improving sorafenib treatment of HCC.