The cytotoxicity effect of 7-hydroxy-3,4-dihydrocadalene from Heterotheca inuloides and semisynthetic cadalenes derivates towards breast cancer cells: involvement of oxidative stress-mediated apoptosis

PeerJ. 2023 Jun 20:11:e15586. doi: 10.7717/peerj.15586. eCollection 2023.

Abstract

Background: Heterotheca inuloides, traditionally employed in Mexico, has demonstrated anticancer activities. Although it has been proven that the cytotoxic effect is attributed to cadinane-type sesquiterpenes such as 7-hydroxy-3,4-dihydrocadalene, the mechanism of action by which these agents act in tumor lines and their regulation remain unknown. This study was undertaken to investigate for first time the cytotoxic activity and mechanism of action of 7-hydroxy-3,4-dihydrocadalene and two semi-synthetic cadinanes derivatives towards breast cancer cells.

Methods: Cell viability and proliferation were assayed by thiazolyl blue tetrazolium bromide (MTT) assay and Trypan blue dye exclusion assay. Cell migration measure was tested by wound-healing assay. Moreover, the reactive oxygen species (ROS) and lipid peroxidation generation were measured by 2',7'-dichlorofluorescein diacetate (DCFH-DA) assay and thiobarbituric acid reactive substance (TBARS) assay, respectively. Furthermore, expression of caspase-3, Bcl-2 and GAPDH were analyzed by western blot.

Results: The results showed that 7-hydroxy-3,4-dihydrocadalene inhibited MCF7 cell viability in a concentration and time dependent manner. The cytotoxic potency of semisynthetic derivatives 7-(phenylcarbamate)-3,4-dihydrocadalene and 7-(phenylcarbamate)-cadalene was remarkably lower. Moreover, in silico studies showed that 7-hydroxy-3,4-dihydrocadalene, and not so the semi-synthetic derivatives, has optimal physical-chemical properties to lead a promising cytotoxic agent. Further examination on the action mechanism of 7-hydroxy-3,4-dihydrocadalene suggested that this natural product exerted cytotoxicity via oxidative stress as evidenced in a significantly increase of intracellular ROS levels and in an induction of lipid peroxidation. Furthermore, the compound increased caspase-3 and caspase-9 activities and slightly inhibited Bcl-2 levels. Interestingly, it also reduced mitochondrial ATP synthesis and induced mitochondrial uncoupling.

Conclusion: Taken together, 7-hydroxy-3,4-dihydrocadalene is a promising cytotoxic compound against breast cancer via oxidative stress-induction.

Keywords: Apoptosis; Breast cancer; Cadalenes; Cytotoxicity; Oxidative stress.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antineoplastic Agents* / pharmacology
  • Apoptosis
  • Asteraceae* / chemistry
  • Breast Neoplasms* / drug therapy
  • Caspase 3 / metabolism
  • Female
  • Humans
  • Oxidative Stress
  • Proto-Oncogene Proteins c-bcl-2 / metabolism
  • Reactive Oxygen Species / metabolism

Substances

  • Caspase 3
  • Reactive Oxygen Species
  • Antineoplastic Agents
  • Proto-Oncogene Proteins c-bcl-2

Grants and funding

This study was funded by the Presupuesto Interno del Instituto de Química/UNAM to Daniela Araiza-Olivera and Programa de Apoyo a Proyectos de Investigación e Innovación Tecnológica (PAPIIT, UNAM IN202219). Alan Mendoza Fuentes received funding from the Programa de Becas Internas-2018 IQ/UNAM, SEP-UNAM-FUNAM-2018 and the Dirección de Becas y Enlace con la comunidad-DGOE. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.