Investigation of anti-tumor mechanisms of K2154: Characterization of tubulin isotypes, mitotic arrest and apoptotic machinery
Journal
Naunyn-Schmiedeberg's Archives of Pharmacology
Journal Volume
374
Journal Issue
3
Pages
223-233
Date Issued
2006
Author(s)
Abstract
Microtubules are crucial targets for cancer chemotherapeutic drugs, and new microtubule-directed agents are of continued interest in drug development. A novel microtubule-directed agent, ethyl-2-[N-ρ-chlorobenzyl-(2′- methoxy)]-anilino-4-oxo -4, 5-dihydro-furan-3-carboxylate, was identified. The compound, designated K2154, inhibited cell proliferation, with IC50 values of 10.3, 15.3, 9.6, 11.2, 12.8 and 12.1 μM in prostate cancer PC-3, hepatocellular carcinoma Hep3B, non-small cell lung cancer A549, colorectal cancer HT29 and HCT116, and P-glycoprotein-rich breast cancer NCI/ADR-RES cells, respectively. Because NCI/ADR-RES cells were susceptible to inhibition by K2154, it indicated that this compound is a poor substrate for P-glycoprotein. In this study, PC-3 cells were used to identify the anticancer mechanisms of K2154. K2154 induced an arrest of the cell cycle at G2/M phase and a subsequent increase of hypodiploid phase in PC-3 cells, whereas it only induced a moderate level of G2/M arrest with little increase of hypodiploid phase in normal prostate cells. K2154 inhibited microtubule assembly in both in vitro turbidity assay and in vivo microtubule spin-down experiment. Immunochemical examination showed that K2154 caused formation of abnormal mitotic characteristics with bipolar spindles, particularly, in βII- and β III-tubulin staining. It also induced several pathways, including cyclin B1 up-regulation, dephosphorylation on Tyr15 and phosphorylation on Thr161 of Cdk1 and Cdc25C phosphorylation, and roscovitine (a Cdk1 inhibitor) significantly inhibited K2154-induced apoptosis, suggesting a pro-apoptotic role of Cdk1. Phosphorylation of Bcl-2 and Bcl-xL and cleavage of Mcl-1, together with activation of caspase-9 and -3, indicated that mitochondrial pathway played a central role in K2154-mediated apoptotic cell death. Additionally, AIF contributed to a late phase of K2154-induced apoptotic pathway. In conclusion, it is suggested that K2154 displays an anticancer activity through a target on microtubules and a subsequent signaling cascade on cell cycle regulation and apoptotic machinery. ? 2006 Springer-Verlag.
SDGs
Other Subjects
antineoplastic agent; carboxylic acid derivative; caspase 3; caspase 9; cyclin B1; cyclin dependent kinase 1; cyclin dependent kinase inhibitor; ethyl 2 [n 4 chlorobenzyl(2' methoxy)]anilino 4 oxo 4,5 dihydrofuran 3 carboxylate; glycoprotein P; k 2154; mitochondrial protein; protein bcl 2; protein bcl xl; roscovitine; threonine; tubulin; tyrosine; unclassified drug; antineoplastic activity; apoptosis; article; breast cancer; cancer cell culture; cell cycle G2 phase; cell cycle M phase; cell cycle regulation; cell death; cell proliferation; cell strain HT29; colorectal cancer; controlled study; drug mechanism; enzyme activation; human; human cell; human tissue; IC 50; immunochemistry; inhibition kinetics; liver cell carcinoma; lung non small cell cancer; male; microtubule; mitosis inhibition; prostate cancer; protein phosphorylation; spindle cell; staining; turbidity; upregulation; Aniline Compounds; Antineoplastic Agents; Apoptosis; Apoptosis Inducing Factor; Caspases; Cell Cycle; Cell Line, Tumor; Cell Proliferation; Cyclin B; Cytochromes c; Drug Delivery Systems; Furans; Humans; Inhibitory Concentration 50; Microtubules; Mitochondria; Mitosis; P-Glycoprotein; Phosphorylation; Tubulin; Up-Regulation
Type
journal article