Effects of 5-ALA mediated photodynamic therapy in oral cancer stem cells

Author(s)

Pinto, Marlene Aparecida Ferreira ; Ferreira, Cassia Bosi Ribeiro ; de Lima, Barbara Evelyn Santos ; Molon, Angela Cristina ; Ibarra, Ana Melissa Coppa ; Cecatto, Rebeca Boltes ; Franco, Adriana Lino dos Santos ; Rodrigues, Maria Fernanda Setlibal Destro

• Document type: Journal article
• Source: JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY; v. 235, p. 10-pg., 2022-09-08.

Abstract

The aim of the present study was to investigate the effects of PDT using the photosensitizer 5-aminoulevulinic acid (5-ALA) in oral squamous cell carcinoma (OSCC) behavior, mainly regarding its role on the cancer stem cell (CSC) phenotypes and in maintenance of the stem cell properties. Two OSCC cell lines were used and divided in the groups: Control, 5-ALA, LED 6 J/cm2 and PDT. MTT and Neutral red assays were used to access cellular viability, cell migration was evaluated by the wound healing assay. The stem cell phenotype was analyzed by flow cytometry to evaluate the CD44high/ESAhigh, CD44high/ESAlow and CD44low populations, by the clonogenic and tumor sphere formation assays as well as by RT-qPCR. The presence of Protoporphyrin IX in each CSC fraction was evaluated by flow cytometry. The OSCC cell lines showed a significant decrease in cell viability and migration after PDT. The percentage of CD44high/ESAhigh cells decreased after PDT, which was associated with an increase in the CD44low cells and with a functional decrease in the colony and sphere formation capacity. CD44high/ESAhigh cells showed increased PpIX, which contributed for their greater sensitivity to PDT. INV gene increased significantly after PDT, indicating cellular differentiation. Altogether, our results demonstrate that 5ALA mediated PDT decreases not only the fraction of oral CSC but also their functional capabilities, inducing their differentiation. (AU)

• FAPESP's process: 19/09465-2 - Effect of photodynamic therapy in the stem cell phenotype of oral squamous cell carcinoma cell lines
• Grantee: Cassia Bosi Ribeiro Ferreira
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• FAPESP's process: 18/08540-8 - Immnunotherapy to target cancer stem cell subpopulations in oral squamous cell carcinoma: the role of natural killer cells
• Grantee: Maria Fernanda Setúbal Destro Rodrigues
• Support Opportunities: Regular Research Grants