cyclin-d1 and paeonol

BACKGROUND This study aimed to investigate the effects of the paeonol-platinum(II) (PL-Pt[II]) complex on SW1736 human anaplastic thyroid carcinoma cell line and the BHP7-13 human thyroid papillary carcinoma cell line in vitro and on mouse SW1736 tumor xenografts in vivo. MATERIAL AND METHODS The cytotoxic effects of the PL-Pt(II) complex on SW1736 cells and BHP7-13 cells was measured using the MTT assay. Western blot measured the expression levels of cyclins, cell apoptotic proteins, and signaling proteins. DNA content and apoptosis were detected by flow cytometry. SW1736 cell thyroid tumor xenografts were established in mice followed by treatment with the PL-Pt(II) complex. RESULTS Treatment of the SW1736 and BHP7-13 cells with the PL-Pt(II) complex reduced cell proliferation in a dose-dependent manner, with an IC50 of 1.25 µM and 1.0 µM, respectively, and increased the cell fraction in G0/G1phase, inhibited p53, cyclin D1, promoted p27 and p21 expression, and significantly increased the sub-G1 fraction. Treatment with the PL-Pt(II) complex increased caspase-3 degradation, reduced the expression of p-4EBP1, p-4E-BP1 and p-S6, and reduced the expression of p-ERK1/2 and p-AKT. Treatment with the PL-Pt(II) complex reduced the volume of the SW1736 mouse tumor xenografts on day 14 and day 21, and reduced AKT phosphorylation and S6 protein expression and increased degradation of caspase-3. CONCLUSIONS The cytotoxic effects of the PL-Pt(II) complex in human thyroid carcinoma cells, including activation of apoptosis and an increased sub-G1 cell fraction of the cell cycle, were mediated by down-regulation of the mTOR pathway.

Topics: Acetophenones; Adaptor Proteins, Signal Transducing; Animals; Apoptosis; Blotting, Western; Caspase 3; Cell Cycle; Cell Cycle Proteins; Cell Line, Tumor; Cell Proliferation; Cyclin D1; Cyclin-Dependent Kinase Inhibitor p21; Cyclin-Dependent Kinase Inhibitor p27; Down-Regulation; Humans; In Vitro Techniques; Mice; Mitogen-Activated Protein Kinase 1; Mitogen-Activated Protein Kinase 3; Neoplasm Transplantation; Phosphorylation; Platinum Compounds; Proto-Oncogene Proteins c-akt; Ribosomal Protein S6 Kinases; Signal Transduction; Thyroid Cancer, Papillary; Thyroid Carcinoma, Anaplastic; Thyroid Neoplasms; TOR Serine-Threonine Kinases; Xenograft Model Antitumor Assays

Paeonol is a simple phenolic compound isolated from herbal root bark, which has been reported to possess numerous biological and pharmacological characteristics, including a desirable anti‑tumor effect. To date, the effect of paeonol against colorectal cancer (CRC) cells is yet to be fully elucidated. Therefore, the present study aimed to identify the underlying mechanism via which paeonol exerts its anti‑tumor activity on HCT116 cells. After incubation with various concentrations of paeonol (7.8125, 15.625, 31.25, 62.5, 125, 250 and 500 µg/ml), the inhibitory effect of paeonol on cell viability was assessed using a Cell Counting Kit‑8 assay. Cell apoptosis and cell cycle distribution were measured using flow cytometry. Moreover, caspase activity was measured using a colorimetric caspase assay. Luciferase assay was also used to determine the β‑catenin‑mediated transcriptional activity of T‑cell specific transcription factor/lymphoid‑enhancer binding factor (TCF/LEF), and western blotting analysis was performed to measure the related expression of proteins. The results indicated that paeonol exhibited a notable effect against HCT116 cells by inducing G0/G1‑phase arrest, as demonstrated by downregulation of the cell cycle regulators cyclin‑dependent kinase 4 and cyclin D1 and upregulation of p21Cip1 in a dose‑dependent manner. Furthermore, paeonol dose‑dependently induced cell apoptosis, accompanied by an increase in the Bax/Bcl‑2 ratio, release of cytochrome c and further activation of caspases. Paeonol also dose‑dependently blocked the activation of the Wnt/β‑catenin signaling pathway by suppressing the expression of β‑catenin, resulting in a decrease in β‑catenin‑mediated activity of TCF/LEF and downregulation of downstream target genes, including cyclin D1, survivin and c‑Myc. Therefore, the present results suggested that paeonol exerted its anti‑tumor effects on CRC cells, including the inhibition of cell proliferation, induction of cell cycle arrest and initiation of apoptosis, at least partly by suppressing the Wnt/β‑catenin pathway, which may offer a promising therapeutic strategy for CRC.

Topics: Acetophenones; Apoptosis; Blotting, Western; Cell Cycle; Cell Cycle Checkpoints; Cell Proliferation; Colorectal Neoplasms; Cyclin D1; Cyclin-Dependent Kinase 4; G1 Phase; HCT116 Cells; Humans; Resting Phase, Cell Cycle; Survivin; Wnt Signaling Pathway

Fibroblast-like synoviocytes (FLS) play an essential role in the pathogenesis of chronic inflammatory diseases, such as rheumatoid arthritis. Paeonol (Pae) is a phenolic compound found in many traditional Chinese medicine remedies. However, the effects of Pae on TNF-α-stimulated FLS and the underlying molecular mechanism are unknown. In this study, we aimed to investigate the anti-proliferative and anti-inflammatory effect of Pae against activated FLS.. Rheumatoid arthritis FLS (RA-FLS) were pre-treated with different doses (25, 50, and 100 µM) of Pae or miR-155 inhibitor for 30 min or transfected with miR-155 mimic, and then treated with 50 ng/mL of tumor necrosis factor alpha (TNF-α) for 1 h. Cells that were untreated served as control. At 24 h after drug pretreatment, the proliferation of FLS was detected using the MTT assay. The concentrations of interleukin IL-6 and IL-1β in cell culture supernatant were examined by enzyme-linked immunosorbent assay (ELISA), and mRNA levels of Foxo3 and miR-155 expression in FLS were quantified by reverse transcription-polymerase chain reaction (RT-PCR). Protein expressions of forkhead box O3 (FOXO3), cyclin D1, and c-Myc were detected by Western Blot.. TNF-α induced the proliferation of FLS, whereas Pae inhibited this proliferation in a dose-dependent manner. Pae attenuated TNF-α-induced production of IL-6 and IL-1β, and inhibited the expression of miR-155 in a dose-dependent manner. In addition, miR-155 inhibitor decreased TNF-α-induced proliferation of FLS, and attenuated TNF-α-induced production of IL-6 and IL-1β. In addition, pretreatment with different doses of Pae or miR-155 inhibitor markedly attenuated TNF-α-induced decrease in protein expression of FOXO3 in FLS. Mechanistic studies revealed FOXO3 as miR-155-5p direct target and inhibition of FOXO3 led to the abolishment of Pae protective effects.. Paeonol protected against TNF-α-induced proliferation and cytokine release of FLS by decreasing the expression of miR-155 and upregulating its target FOXO3.

Topics: Acetophenones; Anti-Inflammatory Agents; Arthritis, Rheumatoid; Cell Proliferation; Cells, Cultured; Cyclin D1; Forkhead Box Protein O3; Humans; Interleukin-1beta; Interleukin-6; MicroRNAs; Proto-Oncogene Proteins c-myc; Synoviocytes; Tumor Necrosis Factor-alpha