The value of each well was detected on Multisken Spectrum microplate reader at 490 nm (Thermo Fisher Scientific). siRNA treatment ACCA siRNA (5-TACAAGGGATACAGGTATTTA-3) and control siRNA (5-CAACAAGATGAAGAGCACCAA-3) used in this study were designed and synthesized by GenePharma (Shanghai, China). were 6.06 and 5.36 g/ml by the treatment of TOFA for 48 h, respectively. Circulation cytometry analysis showed that TOFA markedly arrest cell cycle at G2/M phase and lead to cell apoptosis. In addition, Western blot results revealed that TOFA decreased the phosphorylation of p-Hydroxymandelic acid proteinkinaseB(Akt), Mammalian target of rapamycin (mTOR) and p70 ribosomal protein S6 kinase (p70S6K). What’s more, specific phosphoinositide 3-kinases (PI3K) phosphorylation inhibitor LY294002 potentiated TOFA anti-cancer activity. These results suggested that TOFA induces growth restraint and apoptosis via inhibiting the PI3K/Akt/mTOR pathway and TOFA may be a novel therapeutic strategy for RCC treatment. Keywords: TOFA, Human renal cell carcinoma cell lines, Cell cycle arrest, Cell apoptosis, PI3K/Akt/mTOR Introduction Renal cell carcinoma (RCC) was regarded as the most lethal urological tumor 1. The incidence and mortality rate of RCC are constantly rising at a rate of 2-3% per-decade 2. RCC poses a threat to public healthy due to the 5-12 months relative survival rates at diagnosis is still poor and less than 10% of patients survive over 5 years 3, 4. Therefore, studying the underlying mechanisms and molecular basis of p-Hydroxymandelic acid RCC is an essential prerequisite to develop more effective therapies nowadays. The acetyl-CoA carboxylase (ACC) is at the junction of lipids synthesis and oxidative metabolic pathways. Two ACC isoforms, ACCA (ACC-) and ACCB (ACC-), have been recognized in mammalians, which are encoded by different genes 5. Acetyl-CoA-carboxylase- (ACCA), located in cell cytoplasm, is p-Hydroxymandelic acid usually a key rate-limiting enzyme in the process of fatty acid synthesis, while ACCB controls fatty acid oxidation progression. ACCA catalyzes the reaction of transforming acetyl-CoA to malonyl CoA, which is the initiating process of long-chain fatty acids biosynthesis. ACCA activity is usually purely controlled by a metabolite-mediated allosteric mechanism as well as the transcriptional and posttranslational levels 6, 7. Interestingly, ACCA is usually upregulated in many kinds of human cancers, such as breast and liver carcinoma, and likely contributes to promote lipogenesis and meet the need for quick growth and proliferation 8. The inhibitors or small interfering RNA of ACCA can block fatty acid synthesis, induced cell cycle arresting and p-Hydroxymandelic acid cell growth inhibition in many types of human malignancy cells, such as prostate malignancy 9 and non-small-cell lung malignancy 10. These findings suggest that the ACCA is essential to cell proliferation and apoptosis, which may be a novel therapeutic strategy for malignancy treatment. 5-Tetradecyloxy-2-furoic acid (TOFA) is usually a cell-permeable small molecule and also an allosteric inhibitor of ACCA. TOFA can block the synthesis of fatty acids, thus restraining the Rabbit Polyclonal to Cytochrome P450 2D6 synthesis of phosphatidylcholine, which involved in the generation of cell membranes 11. According to previous reports, TOFA suppressed proliferation and induced apoptosis in the colon cancer cell lines HCT-8 and HCT-15 12, the prostate malignancy cell collection LNCAP 13 and ovarian malignancy cell collection COC1 14. However, the possible effects and mechanisms of TOFA on RCC cell lines are still not elucidated. Therefore, we investigated the functions of TOFA, acted as an ACCA inhibitor, in proliferation, cell cycle progression and apoptosis of RCC cell lines ACHN and 786-O. With original attention paid to explore the potential mechanism in the clinical management of RCC, the PI3K/Akt/mTOR signaling pathway mediating the effect of TOFA around the RCC cell lines ACHN and 786-O was further examined. Materials and methods Reagents and antibodies TOFA was obtained from SANTA CRUZ (California, USA), Fetal bovine serum (FBS), DMEM medium and penicillin/streptomycin were obtained from Hyclone (Logan, UT, USA). 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide (MTT) Annexin V-FITC/PI Apoptosis Detection Kit and Cell Cycle p-Hydroxymandelic acid Assay Kit were purchased from Beyotime (Jiangsu, China). Bovine serum albumin (BSA), Dimethyl sulfoxide (DMSO), Ribonuclease (RNase A) and LY294002 were purchased from Sigma-Aldrich (St.Louis,MO,USA). RIPA Lysis Buffer, Pierce? BCA protein assay kit, protease inhibitor cocktail, the polyvinylidene difluoride (PVDF) membrane and Super Transmission West Pico Chemiluminescent Substrate detection kit was purchased from Thermo Fisher Scientific (Waltham, MA, United States). The antibodies such as p21Cip1/Waf1, CDK1, Cyclin B1, Bax, Bcl-2, Cleaved caspase 3, p-AKT (Ser473), p-mTOR (Ser2448), p-p70S6K (Ser371) and GAPDH were obtained from Cell Signaling Technology Inc. (Beverly, MA, USA). Cell culture and Cell viability assay ACHN and 786-O cells were purchased from Cobioer Biosciences (Nanjing, China) and cultured in DMEM medium supplemented with 10% FBS in a humidified atmosphere with 37C and 5% CO2. The stock answer of TOFA was 10 mg/ml dissolved in DMSO. TOFA was incubated with the cells (4.5103 cells/well) at numerous working concentrations (0, 2, 4, 6, 8, 10 g/ml) in 96-well plates. Viable cells were measured by MTT at an indicated time. Following 3 h.