Combination treatment of renal cell carcinoma with belinostat and 5-fluorouracil: a role for oxidative stress induced DNA damage and HSP90 regulated thymidine synthase.

Abstract

PURPOSE:

Despite several therapeutic options renal cell carcinoma is associated with a poor clinical outcome. Therefore, we investigated whether combining 5-fluorouracil with the histone deacetylase inhibitor belinostat would exert a synergistic effect on renal cell carcinoma cells in vitro and in vivo.

MATERIALS AND METHODS:

We used SN12C cells treated with 5-fluorouracil and/or belinostat in vitro and in xenograft experiments in vivo. Cell viability and death mechanisms were assessed by MTS assay and Western blot. To investigate the role of reactive oxygen species we used H2DCF-DA, reactive oxygen species scavengers and the roGFP2 construct.

RESULTS:

Belinostat potentiated the anticancer effect of 5-fluorouracil. It synergistically induced apoptosis by activating caspases and increasing the subG1 cell population. Effects on reactive oxygen species mediated DNA damage included decreased thioredoxin expression and increased levels of TBP-2, γ-H2AX and Ac-H3. Furthermore, belinostat attenuated the 5-fluorouracil mediated induction of thymidylate synthase via HSP90 hyperacetylation. Co-administration of 5-fluorouracil with belinostat similarly reduced tumor volume and weight, and increased γ-H2AX and Ac-H3 levels in the SN12C xenograft model.

CONCLUSIONS:

In combination with 5-fluorouracil the targeted inhibitor of histone deacetylase synergistically inhibited renal cancer cell growth by the blockade of thymidylate synthase induction and the induction of reactive oxygen species mediated DNA damage in vitro and in vivo. Our results suggest that combined treatment with belinostat and 5-fluorouracil may represent a promising new approach to renal cancer.

• Authors: Mi Joung Kim, Jee Suk Lee, Sang Eun Park, Hye-Jin Yi, In Gab Jeong, Jong Soon Kang, Jieun Yun, Joo-Yong Lee, Seonggu Ro, Jung Shin Lee, Eun Kyung Choi, Jung Jin Hwang, Choung-Soo Kim
• Journal: The Journal of urology (J Urol) Vol. 193 Issue 5 Pg. 1660-8 (May 2015) ISSN: 1527-3792 [Electronic] United States
• PMID: 25433307 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: Copyright © 2015 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

Chemical References

• Antimetabolites, Antineoplastic
• HSP90 Heat-Shock Proteins
• Histone Deacetylase Inhibitors
• Hydroxamic Acids
• Sulfonamides
• Nitric Oxide Synthase
• Thymidylate Synthase
• belinostat
• Fluorouracil

Topics

• Animals
• Antimetabolites, Antineoplastic (administration & dosage)
• Antineoplastic Combined Chemotherapy Protocols (administration & dosage)
• Carcinoma, Renal Cell (drug therapy, metabolism)
• DNA Damage (drug effects)
• Drug Therapy, Combination
• Fluorouracil (administration & dosage)
• HSP90 Heat-Shock Proteins (drug effects)
• Histone Deacetylase Inhibitors (administration & dosage)
• Humans
• Hydroxamic Acids (administration & dosage)
• Kidney Neoplasms (drug therapy, metabolism)
• Mice
• Mice, Inbred BALB C
• Nitric Oxide Synthase
• Oxidative Stress (drug effects)
• Sulfonamides (administration & dosage)
• Thymidylate Synthase (drug effects)
• Tumor Cells, Cultured