Evidence map›Paper›PMID 41831631›Full record

ArticlePhotodiagnosis and photodynamic therapy2026

Photobiomodulation pre-treatment enhances ALA-induced PpIX accumulation and photodynamic therapy response in oral squamous cell carcinoma cells in cell culture.

Ana Paula Ferro, Sally Kyei Mensah, Yi Ran Liu, Elaine Caldeira de Oliveira Guirro, Jonathan P Celli

Abstract read
In one paragraph

Article in Photodiagnosis and photodynamic therapy, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 1 paper.

0numbers the graph read from it
0cells of the map it votes in
1citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

1 citing paper in PubMed.

  1. Review
4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

5 authors.

Ana Paula FerroDepartment of Health Sciences, Postgraduate Program in Rehabilitation and Functional Performance, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, São Paulo, Brazil.
Sally Kyei MensahDepartment of Physics, University of Massachusetts Boston, Boston MA, United States.
Yi Ran LiuDepartment of Physics, University of Massachusetts Boston, Boston MA, United States.
Elaine Caldeira de Oliveira GuirroDepartment of Health Sciences, Postgraduate Program in Rehabilitation and Functional Performance, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, São Paulo, Brazil.
Jonathan P CelliDepartment of Physics, University of Massachusetts Boston, Boston MA, United States; Center for Personalized Cancer Therapy, University of Massachusetts Boston, Boston, MA, United States. Electronic address: Jonathan.celli@umb.edu.

Funding

UMass Boston-DF/HCC U54 Partnership (2 of 2)U54CA156734 · NCI · UNIVERSITY OF MASSACHUSETTS BOSTON · PI Jan Mutchler · 2010 to 2026
$24.9M
NCI NIH HHS U54 CA156734
6 · The paper itself

Abstract

introductionPhotodynamic therapy (PDT) and photobiomodulation (PBM) are light-based modalities with differing applications but which share overlapping spectral and irradiance requirements. PDT, which uses an exogenous photosensitizer, can be used to impart a selective cytotoxic response in target malignant tissues, while PBM is typically used to stimulate biological responses that are beneficial in healthy tissues. The inherent compatibility in light delivery requirements suggests the potential for exploring interactions between these modalities which could enhance tumor response to PDT.

objectiveWe sought to evaluate the capability of photobiomodulation (PBM) pretreatment to enhance aminolaevulinic acid (ALA)-induced protoporhyrin IX (PpIX) photosensitization, and subsequent PDT response in oral squamous cell carcinoma (OSCC) cells. MATERIAL AND

methodsOSCC cell cultures were initially treated with 635 or 830 nm irradiation at various fluences to examine fluence and wavelength dependence of PBM effects. Fluence-dependent changes in mitochondrial dehydrogenase activity as an indicator of mitochondrial metabolic function were assessed by the MTS assay. PBM treated cultures were also lysed to assess PpIX accumulation via fluorescence analysis. Cytotoxic response in cultures treated with PDT with or without PBM priming/pre-treatment at varying fluences were assessed by image analysis following staining with calcein acetoxymethyl ester and ethidium bromide.

resultsPhotobiomodulation (PBM) using red (635 nm) or infrared (830 nm) light sources produced dose-dependent increases in mitochondrial dehydrogenase activity (as measured by the MTS assay) with minimal evidence of phototoxicity in oral squamous cell carcinoma (OSCC) cells. The accumulation of PpIX resulting from ALA incubation increased significantly in OSCC cells that were pre-treated with PBM relative to controls. The combination of PBM and PDT showed significantly increased cytotoxic response compared to PDT alone.

conclusionsPBM enhances ALA-induced PpIX accumulation, and subsequent PDT response in OSCC cells. This enhancement effect can be achieved using the same light source as for PpIX photoactivation suggesting potential as a clinically practical pre-treatment to enhance efficacy of ALA-PDT.

Indexed as

Aminolevulinic AcidCarcinoma, Squamous CellLow-Level Light TherapyMouth NeoplasmsPhotochemotherapyPhotosensitizing AgentsProtoporphyrinsCell Line, TumorCell SurvivalHumansRed LightAminolevulinic AcidPhotosensitizing Agentsprotoporphyrin IXProtoporphyrinsAminolevulinic acid (ALA)Oral cancerPhotobiomodulationPhotodynamic therapy (PDT)Protoporphyrin IX

Identifiers

PMID41831631
PMCPMC13070571

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LicenceCC BY-NC-ND
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Registered trials

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.