cerulenin and Urinary-Bladder-Neoplasms

The aim of the present study was to investigate the effect of fatty acid synthase complex (FASN) on the migration capacity of bladder transitional cell carcinoma (BTCC) cells and the involvement of matrix metalloproteinase‑9 (MMP‑9) via targeting of phospho‑AKT (p‑AKT). FASN‑specific small‑interfering RNA (FASN‑siRNA) was used to inhibit FASN gene expression in the 5637 and 253J BTCC cell lines. The knockdown efficiency of FAM‑conjugated FASN‑siRNA was confirmed by fluorescence microscopy. The migratory abilities of BTCC cells were assessed using a Transwell assay. Furthermore, protein and mRNA expression of FASN, p‑AKT, AKT, and migration‑associated protein MMP‑9 were detected by western blot analysis. Treatment with FASN inhibitor Cer and FASN‑siRNA decreased the migratory capacity of bladder cancer cells and reduced the levels of p‑AKT as well as the expression of MMP‑9. These results indicated that FASN inhibition suppressed the migratory capacity of BTCC cells through suppressing AKT activation and consequently reducing MMP‑9 expression. Targeting FASN may represent a promising novel therapeutic strategy for BTCC.

Topics: Cell Line, Tumor; Cell Movement; Cerulenin; Down-Regulation; Fatty Acid Synthases; Gene Knockdown Techniques; Humans; Phosphorylation; Proto-Oncogene Proteins c-akt; RNA, Small Interfering; Urinary Bladder Neoplasms

To investigate the role of fatty acid synthase (FASN) in bladder transitional cell carcinoma (BTCC).. FASN expression was investigated in non-muscle-invasive BTCC tissue specimens by immunohistochemistry and BTCC cell lines by Western blot. After treatment with FASN-siRNA or FASN inhibitor cerulenin (Cer), the proliferation and apoptosis of BTCC cell lines 5637 and 253 J were determined by cell counting Kit-8 (CCK8) assay and flow cytometry respectively. The expression of p-AKT, cyclin D1 (CCND1), and apoptosis-related proteins were detected by Western blot.. High levels of FASN expression were observed in 59% (32/54) of non-muscle-invasive BTCC tissue specimens, and FASN expression was associated with histologic grade (P < .05) and recurrence (P < .05). FASN expression was high in 6 BTCC cell lines. FASN inhibitor Cer and FASN-siRNA produced the increased apoptosis and decreased proliferation of bladder cancer cells, and caused inactivity of AKT and downregulation of CCND1. Furthermore, treatment of BTCC cell lines with Cer resulted in apoptosis via the caspase-dependent pathway involving inactivation of antiapoptotic bcl-2 protein.. Our data suggest that FASN plays an important role in BTCC development. Targeting FASN may be a new therapeutic strategy for BTCC.

Topics: Aged; Apoptosis; Carcinoma, Transitional Cell; Cerulenin; Fatty Acid Synthases; Fatty Acid Synthesis Inhibitors; Female; Humans; Male; Proto-Oncogene Proteins c-akt; Tumor Cells, Cultured; Urinary Bladder Neoplasms

Activation of ras oncogenes occurs in a high percentage of tumors, making the enzymes involved in the posttranslational processing of their encoded proteins (p21s) attractive targets for the development of new drugs. Although most effort has focused on farnesyl transferase, which catalyzes the first processing step, attachment of palmitate to p21 is required for optimal transformation by H-ras and N-ras. We have demonstrated that the natural product cerulenin ([2R,3S]-2,3-epoxy-4-oxo-7,10-trans,trans-dodecadienamide) inhibits the palmitoylation of H-ras- and N-ras-encoded p21s in parallel with inhibition of cell proliferation. More than 30 analogues of cerulenin, both aromatic and aliphatic, with various chain lengths and amide substitutions, have been synthesized for use in SAR studies. Studies on the inhibition of T24 cell proliferation indicate that the alpha-keto-epoxy moiety is critical for cytotoxicity, while alkyl chain length had only modest effects on potency. Several compounds inhibited the incorporation of [(3)H]palmitate into p21 in intact T24 cells, with the unsubstituted carboxamides being more active than N,N-dimethyl compounds. In contrast to the effects on palmitoylation, the only compounds which inhibited fatty acid synthase contained alkyl side chains of 12 carbons or fewer. Regression analyses indicated that inhibition of palmitoylation is more closely related to inhibition of proliferation than is inhibition of fatty acid synthase. Further characterization of the molecular pharmacology of these and analogous compounds may define a new class of drugs with antitumor activity.

Topics: Alkyl and Aryl Transferases; Amides; Antineoplastic Agents; Cell Division; Cerulenin; Enzyme Inhibitors; Epoxy Compounds; Farnesyltranstransferase; Fatty Acid Synthases; Humans; Molecular Structure; Oncogene Protein p21(ras); Palmitic Acid; Structure-Activity Relationship; Tumor Cells, Cultured; Urinary Bladder Neoplasms