4-methylene-2-octyl-5-oxofuran-3-carboxylic-acid and Neoplasms

Lipid droplets (LD) are newly characterized dynamic cytoplasmic organelle which is the storehouse of different immunosuppressive cytokines and enzymes like cyclooxygenase and lipoxygenase. Tumors are known to modulate the immune system by immune-editing the microenvironment. Immuno-editing comprises of three steps namely cancer immune-surveillance, tumor dormancy and finally escape leading to tumor development. The latency of the tumor microenvironment is greatly contributed by the M2 polarized macrophages and TGF-β is a prime culprit. Modulating M2 macrophages to M1 can be a strategy against tumor progression. We found that tumor-conditioned medium or recombinant TGF-β was efficient to induce LD formation in Raw264.7 cells and the inhibition of LD was associated with the switch of M2 to M1 phenotype involving MEK1/2 axis. Signature molecules of M2 polarized macrophages like CD206 were also downregulated while co-stimulatory molecules like CD80, CD86 were up-regulated along with enhanced surface expression of MHCII when these macrophages were subjected to C75 treatment to reduce the LD formation. The level of pro-inflammatory cytokine, as well as ROS and NO generation, were also increased when TGF-β treated macrophages were subjected to C75 treatment. This study is probably the first report of this kind and can be used in the future in cancer treatment.

Topics: 4-Butyrolactone; Animals; Cell Line, Tumor; Cytokines; Female; Humans; Lipid Droplets; Macrophages; Male; Mice; Mice, Inbred BALB C; Neoplasms; Nitric Oxide; Phenotype; RAW 264.7 Cells; Reactive Oxygen Species; THP-1 Cells; Tumor Microenvironment

Topics: Acetyl-CoA Carboxylase; Animals; Antineoplastic Agents; ATP Citrate (pro-S)-Lyase; Biosynthetic Pathways; Fatty Acid Synthases; Fatty Acids; Humans; Lipogenesis; Models, Chemical; Molecular Structure; Neoplasms

Fatty acid synthase (FASN) is a novel druggable target for metabolically treating and preventing human malignancies. We envisioned that if loss of sensitivity to C75 (a slow-binding FASN inhibitor) occurs in parallel with loss of FASN expression and/or activity, a mathematical assessment of the nature of the interaction between investigational FASN modulators and C75 may predict the ability of experimental compounds to regulate FASN. We statistically compared the arithmetical sums of the anti-proliferative effects obtained when FASN modulators and C75 were used as single agents to those observed experimentally when agents were actually combined in a sequential schedule (i.e., FASN modulator-->C75). A reduced sensitivity to C75 (antagonism) occurred when compounds down-regulated FASN activity/expression, while an enhanced C75 efficacy (synergism) was found following exposure to FASN up-regulators. This "C75-sensitivity test" might offer an easy, rapid and objective method to identify FASN inhibitors with potential anticancer value in human cancer.

Topics: 4-Butyrolactone; Antineoplastic Agents; Blotting, Western; Cell Line, Tumor; Drug Resistance, Neoplasm; Drug Screening Assays, Antitumor; Enzyme Inhibitors; Fatty Acid Synthase, Type I; Fluorescent Antibody Technique; Humans; In Situ Nick-End Labeling; Models, Theoretical; Neoplasms; RNA Interference