An Investigation of Structure-Activity Relationships and Cell Death Mechanisms of the Marine Alkaloids Discorhabdins in Merkel Cell Carcinoma Cells

A library of naturally occurring and semi-synthetic discorhabdins was assessed for their effects on Merkel cell carcinoma (MCC) cell viability. The set included five new natural products and semi-synthetic compounds whose structures were elucidated with NMR, HRMS, and ECD techniques. Several discorhabdins averaged sub-micromolar potency against the MCC cell lines tested and most of the active compounds showed selectivity towards virus-positive MCC cell lines. An investigation of structure-activity relationships resulted in an expanded understanding of the crucial structural features of the discorhabdin scaffold. Mechanistic cell death assays suggested that discorhabdins, unlike many other MCC-active small molecules, do not induce apoptosis, as shown by the lack of caspase activation, annexin V staining, and response to caspase inhibition. Similarly, discorhabdin treatment failed to increase MCC intracellular calcium and ROS levels. In contrast, the rapid loss of cellular reducing potential and mitochondrial membrane potential suggested that discorhabdins induce mitochondrial dysfunction leading to non-apoptotic cell death.

Medienart:

E-Artikel

Erscheinungsjahr:

2023

Erschienen:

2023

Enthalten in:

Zur Gesamtaufnahme - volume:21

Enthalten in:

Marine drugs - 21(2023), 9 vom: 29. Aug.

Sprache:

Englisch

Beteiligte Personen:

Orfanoudaki, Maria [VerfasserIn]
Smith, Emily A [VerfasserIn]
Hill, Natasha T [VerfasserIn]
Garman, Khalid A [VerfasserIn]
Brownell, Isaac [VerfasserIn]
Copp, Brent R [VerfasserIn]
Grkovic, Tanja [VerfasserIn]
Henrich, Curtis J [VerfasserIn]

Links:

Volltext

Themen:

Alkaloids
Caspases
Discorhabdin
EC 3.4.22.-
Journal Article
Mechanism of action
Merkel cell carcinoma
Structure–activity relationship

Anmerkungen:

Date Completed 28.09.2023

Date Revised 03.10.2023

published: Electronic

Citation Status MEDLINE

doi:

10.3390/md21090474

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM362514097