Portuguese propolis antitumoral activity in melanoma involves ROS production and induction of apoptosis

• Published in: Molecules (Basel, Switzerland) Vol. 27; no. 11; p. 3533
• Main Authors: Oliveira, Rafaela Dias, Celeiro, Sónia Pires, Barbosa-Matos, Catarina, Freitas, Ana Sofia, Cardoso, Susana M., Viana-Pereira, Marta, Almeida Aguiar, Cristina, Baltazar, Fátima
• Format: Journal Article
• Language: English
• Published: Switzerland Multidisciplinary Digital Publishing Institute 31.05.2022; MDPI AG; MDPI
• Subjects: Acetic acid; antioxidant activity; Antioxidants; antitumoral activity; Apoptosis; Biotecnologia Médica; Butanol; cancer; Cancer therapies; Cell culture; Cell viability; Chromatography; Ciências Médicas; DNA probes; Drug development; Ethyl acetate; Flavonoids; Flow cytometry; Genomes; Hexanes; Kinases; Medicina Básica; MEK inhibitors; Melanoma; Metastases; Mutation; Natural products; Portuguese propolis; pro-oxidant activity; Propolis; Scavenging; Science & Technology; Skin cancer; Therapeutic applications; Portugal; antitumoral activity; pro-oxidant activity; apoptosis; melanoma; Portuguese propolis; cancer; antioxidant activity
• ISSN: 1420-3049; 1420-3049
• DOI: 10.3390/molecules27113533

Melanoma is the most aggressive and life-threatening skin cancer type. The melanoma genome is the most frequently mutated, with the BRAF mutation present in 40–60% of melanoma cases. BRAF -mutated melanomas are characterized by a higher aggressiveness and progression. Adjuvant targeted treatments, such as BRAF and MEK inhibitors, are added to surgical excision in BRAF -mutated metastatic melanomas to maximize treatment effectiveness. However, resistance remains the major therapeutic problem. Interest in natural products, like propolis, for therapeutic applications, has increased in the last years. Propolis healing proprieties offer great potential for the development of novel cancer drugs. As the activity of Portuguese propolis has never been studied in melanoma, we evaluated the antitumoral activity of propolis from Gerês (G18.EE) and its fractions ( n -hexane, ethyl acetate (EtOAc), and n -butanol) in A375 and WM9 melanoma cell lines. Results from DPPH•/ABTS• radical scavenging assays indicated that the samples had relevant antioxidant activity, however, this was not confirmed in the cell models. G18.EE and its fractions decreased cell viability (SRB assay) and promoted ROS production (DHE/Mitotracker probes by flow cytometry), leading to activation of apoptotic signaling (expression of apoptosis markers). Our results suggest that the n -BuOH fraction has the potential to be explored in the pharmacological therapy of melanoma. Foundation for Science and Technology (FCT)—projects UIDB/04050/2020, UDBI/04033/2020, UIDB/50026/2020, UIDP/50026/2020, UIDB/50006/2020, UIDP/50006/2020, and by the project NORTE-01-0145-FEDER-000055, supported by the Norte Portugal Regional Operational Programme (NORTE 2020), under the PORTUGAL 2020 Partnership Agreement, through the European Regional Development Fund (ERDF). S.P.C., C.B.M. and A.S.F. are recipients of FCT grants (2020.05779.BD, SFRH/BD/145955/2019, and PD/BD/128276/2017, respectively)