Aluminium (III) phthalocyanine chloride tetrasulphonate is an effective photosensitizer for the eradication of lung cancer stem cells

Anine Crous; Heidi Abrahamse

doi:10.1098/rsos.210148

Aluminium (III) phthalocyanine chloride tetrasulphonate is an effective photosensitizer for the eradication of lung cancer stem cells

R Soc Open Sci. 2021 Sep 8;8(9):210148. doi: 10.1098/rsos.210148. eCollection 2021 Sep.

Authors

Anine Crous¹, Heidi Abrahamse¹

Affiliation

¹ Laser Research Centre, Faculty of Health Sciences, University of Johannesburg, PO Box 17011, Johannesburg 2028, South Africa.

Abstract

Cancer stem cells (CSCs) are considered to contribute to the recurrence of lung cancer due to their stem-like nature and the involvement of genetic markers associated with drug efflux, regeneration and metastases. Photodynamic therapy (PDT) is a cost-effective and non-invasive therapeutic application that can act as an alternative therapy for lung cancer when considering CSC involvement. Stem-like cells derived from the A549 lung cancer cell line, positive for CD133, CD56 and CD44 antigen markers, were characterized, intracellular localization of aluminium (III) phthalocyanine chloride tetrasulphonate (AlPcS₄Cl) determined and its anti-cancer PDT effects were evaluated. Results confirmed that isolated cells were stem cell-like and subcellular localization of AlPcS₄Cl in integral organelles involved in cell homeostasis supported the destruction of CSC. AlPcS₄Cl's effectivity was demonstrated with CSC eradication showing a significant increase in cytotoxicity and cell death via apoptosis, caused by a decrease in mitochondrial membrane potential. PDT could serve as a palliative treatment for lung cancer and improve prognosis by elimination of lung CSCs.

Keywords: cell death; cytotoxicity; lung cancer stem cells; photodynamic therapy; photosensitizer.