Redox modulation of oxidatively-induced DNA damage by ascorbate enhances both in vitro and ex-vivo DNA damage formation and cell death in melanoma cells

Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved..

Elevated genomic instability in cancer cells suggests a possible model-scenario for their selective killing via the therapeutic delivery of well-defined levels of further DNA damage. To examine this scenario, this study investigated the potential for redox modulation of oxidatively-induced DNA damage by ascorbate in malignant melanoma (MM) cancer cells, to selectively enhance both DNA damage and MM cell killing. DNA damage was assessed by Comet and ɣH2AX assays, intracellular oxidising species by dichlorofluorescein fluorescence, a key antioxidant enzymatic defence by assessment of catalase activity and cell survival was determined by clonogenic assay. Comet revealed that MM cells had higher endogenous DNA damage levels than normal keratinocytes (HaCaT cells); this correlated MM cells having higher intracellular oxidising species and lower catalase activity, and ranked with MM cell melanin pigmentation. Comet also showed MM cells more sensitive towards the DNA damaging effects of exogenous H2O2, and that ascorbate further enhanced this H2O2-induced damage in MM cells; again, with MM cell sensitivity to induced damage ranking with degree of cell pigmentation. Furthermore, cell survival data indicated that ascorbate enhanced H2O2-induced clonogenic cell death selectively in MM cells whilst protecting HaCaT cells. Finally, we show that ascorbate serves to enhance the oxidising effects of the MM therapeutic drug Elesclomol in both established MM cells in vitro and primary cell cultures ex vivo. Together, these results suggest that ascorbate selectively enhances DNA damage and cell-killing in MM cells. This raises the option of incorporating ascorbate into clinical oxidative therapies to treat MM.

Medienart:

E-Artikel

Erscheinungsjahr:

2024

Erschienen:

2024

Enthalten in:

Zur Gesamtaufnahme - volume:213

Enthalten in:

Free radical biology & medicine - 213(2024) vom: 17. Feb., Seite 309-321

Sprache:

Englisch

Beteiligte Personen:

Najeeb, Hishyar A [VerfasserIn]
Sanusi, Timi [VerfasserIn]
Saldanha, Gerald [VerfasserIn]
Brown, Karen [VerfasserIn]
Cooke, Marcus S [VerfasserIn]
Jones, George Dd [VerfasserIn]

Links:

Volltext

Themen:

Antioxidants
Ascorbate
Ascorbic Acid
BBX060AN9V
Catalase
Cell death
Comet assay
EC 1.11.1.6
Hydrogen Peroxide
Journal Article
Malignant melanoma
Oxidatively-induced DNA damage
PQ6CK8PD0R
Research Support, N.I.H., Extramural
Research Support, Non-U.S. Gov't

Anmerkungen:

Date Completed 19.02.2024

Date Revised 19.02.2024

published: Print-Electronic

Citation Status MEDLINE

doi:

10.1016/j.freeradbiomed.2024.01.019

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM367529637