stilbenes and Cholangiocarcinoma

Autophagy is an evolutionarily conserved catabolic mechanism to maintain energy homeostasis and to remove damaged cellular components, which plays an important role in the survival of various cells. Inhibiting autophagy is often applied as a new strategy to halt the growth of cancer cells.. The effect of FOXO1 gene on cellular function and apoptosis and its underlying mechanisms were investigated in cultured QBC939 cells by the methylthiazoletetrazolium (MTT) assay, western blot, DCFDA mitochondrial membrane potential, and ATP content measurement. FOXO1 siRNA was applied to down-regulate FOXO1 expression in QBC939 cells.. Here we reported that FOXO1, acetylation of FOXO1 (Ac-FOXO1) and the following interaction between Ac-FOXO1 and Atg7 regulated the basal and serum starvation (SS)-induced autophagy as evidenced by light chain 3 (LC3) accumulation and p62 degration. Either treatment with FOXO1 siRNA or resveratrol, a sirt1 agonist, inhibited autophagic flux, resulting in oxidative stress, mitochondrial dysfunction (MtD) and apoptosis in QBC939 cells, which were attenuated by enhancing autophagy with rapamycin. On the contrary, inhibiting autophagic flux with 3-MA worsened all these effects in QBC939 cells.. Taken together, our study for the first time identified FOXO1 as a potential therapeutic target to cure against human cholangiocarcinoma via regulation of autophagy, oxidative stress and MtD.

Topics: Acetylation; Apoptosis; Autophagy; Autophagy-Related Protein 7; Bile Duct Neoplasms; Cell Line, Tumor; Cholangiocarcinoma; Forkhead Box Protein O1; Humans; Membrane Potential, Mitochondrial; Microtubule-Associated Proteins; Oxidative Stress; Resveratrol; RNA Interference; RNA, Small Interfering; Sequestosome-1 Protein; Stilbenes

Cholangiocarcinomas are devastating cancers that are resistant to chemotherapies. Resveratrol, a food-derived polyphenol with antitumorigenic properties, can regulate the expression of cytochrome p450 1b1 (Cyp1b1), which may confer chemoresistance in various cancers. Our aims were to assess the effects of resveratrol on the sensitivity of cholangiocarcinoma cells to chemotherapeutic agents and show an association between Cyp1b1 expression and chemosensitivity. Cholangiocarcinoma cell lines were treated with resveratrol before the addition of 5-fluorouracil (5-FU), gemcitabine, or mitomycin C. Cell proliferation and apoptosis were assessed by MTS assays and Annexin staining. Resveratrol effects on cholangiocarcinoma tumor sensitivity to 5-FU was assessed in an in vivo xenograft model using Mz-ChA-1 cells. After resveratrol treatment, Cyp1b1 expression was assessed by real-time PCR and immunoblotting. Stable-transfected cell lines with Cyp1b1 expression knocked down (Mz-Cyp1b1) were used to assess sensitivity to chemotherapeutic agents by MTS assays and Annexin staining and in a xenograft model using Mz-ChA-1 and Mz-Cyp1b1 cells, respectively. For each chemotherapeutic agent, co-treatment with resveratrol in vitro decreased cell proliferation and increased apoptosis to a greater extent than with the chemotherapeutic agent alone. In vivo, 5-FU+resveratrol decreased tumor size and increased TUNEL staining to a greater extent than 5-FU alone. In parallel, resveratrol decreased Cyp1b1 expression in Mz-ChA-1 cells and in cholangiocarcinoma tumors. Mz-Cyp1b1 cells were more sensitive to chemotherapeutic agents in vitro than mock-transfected cells, and Mz-Cyp1b1-induced tumors were more susceptible to 5-FU treatment. We suggest that resveratrol treatment may be a useful adjunct therapy to improve chemosensitivity in cholangiocarcinoma.

Topics: Animals; Antineoplastic Agents; Apoptosis; Cell Proliferation; Cholangiocarcinoma; Cytochrome P-450 Enzyme System; Deoxycytidine; Fluorouracil; Gemcitabine; Mice; Mice, Nude; Mitomycin; Resveratrol; Stilbenes

Cholangiocarcinoma is a devastating tumour with a poor prognosis. An efficient therapy is unavailable in unoperable patients and new drugs are widely sought for and required. Resveratrol (RES) is a natural molecule with a reported anticancer effect, evaluated on different tumour cell lines. We tested the efficacy of RES on a cholangiocarcinoma cell line for the first time.. We used the human SK-ChA-1 cell line, cultured in the classical two-dimensional model and in the three-dimensional spheroids. After RES exposure morphology, cell viability (colony-forming assay), lactate dehydrogenase (LDH), alkaline phosphatase (ALP) and cancer antigen (CA) 19-9 medium releases, cellular transglutaminase activity, karyotype and cell cycle were evaluated.. Resveratrol inhibited cell growth in both the cell culture systems used (from -15 to -80% vs untreated controls) and induced a 40-fold increase of LDH and ALP activities in the culture medium. Also, transglutaminase (TG) activity increased in the cell lysates, together with a cell cycle perturbation characterised by an accumulation in the G(1)/S phase. Karyotype and CA 19-9 expression were not influenced by the treatment.. The observed cytotoxic effect of RES on the human cholangiocarcinoma SK-ChA-1 cell line cultured two- and three-dimensionally suggests to further analyse its chemotherapic/chemopreventive possibilities for this kind of cancer.

Topics: Alkaline Phosphatase; Cell Line, Tumor; Cell Survival; Cholangiocarcinoma; Colony-Forming Units Assay; Dose-Response Relationship, Drug; Enzyme Activation; Flow Cytometry; Fluorescent Antibody Technique; Humans; Karyotyping; L-Lactate Dehydrogenase; Microscopy, Electron, Scanning; Resveratrol; Stilbenes; Transglutaminases