PhD Scientific Days 2025

Poster Session III. - C: Molecular Medicine

Tyrosinase Expression Increases Melanoma Sensitivity to GPX4 Inhibition

Előadó neve

Pál Dorottya

Neptun code

PJDI3L

Előadó munkahelye

Department of Physiology

Előadó telefonszáma

+36707913570

Előadó e-mail címe

pal.dorottya@phd.semmelweis.hu

Az előadás címe

Tyrosinase Expression Increases Melanoma Sensitivity to GPX4 Inhibition

Szerző(k) neve és munkahelye

Dorottya Pál¹, Alexandra Lakatos¹, Botond Szabolcs MD.^1,2, Benedek Nagy¹, Lajos Vince Kemény MD, PhD^1,2

1: HCEMM-SU Translational Dermatology Research Group, Department of Physiology-Semmelweis University
2: Department of Dermatology, Venerology and Dermatooncology, Semmelweis University

Bemutatás módja

Poszter

Szekció

Poster Session III. - C: Molecular Medicine

Language of the presentation

Hungarian

Preferred session

Molecular Medicine

Összefoglaló szövege

Introduction
Due to limited treatments overcoming resistance to targeted immunotherapies in metastatic melanoma, understanding cell death pathways is crucial. In melanoma, reactive oxygen species have been demonstrated to play a significant and complex role. Lipid ROS induced, iron dependent ferroptosis shows therapeutic potential in dedifferentiated, multi-drug resistant melanoma. However, the mechanisms underlying the sensitivity of dedifferentiated cells and the resistance of differentiated cells to ferroptosis remain unclear.

Aims
We aimed to investigate the role of pigmentation in modulating ferroptosis cell death in melanoma.

Method
The activity of tyrosinase was modulated by the genetic ablation of the TYR gene using CRISPR-Cas9 in mouse and human melanoma cells. Clones lacking tyrosinase mRNA were utilized to create a genetic model of tyrosinase deficiency. Some experiments involved pharmacological inhibition of tyrosinase, achieved by pretreating pigmented cells with 200μM of PTU for at least five days. Viability assays were conducted using various compounds that induce ferroptosis. Melanoma cell lines were treated with ferroptosis inducing compounds at 10 different concentrations. Cell viability was assessed using the CellTiter-Glo Assay. To detect Lipid ROS, cells were treated with 3μM RSL3, and Bodipy C11 was added to each well then incubated. The extent of lipid peroxidation was measured with Leica and quantified using ImageJ. Glutathione levels were measured following the manufacturer’s instructions in both human and mouse melanoma cells. We examined GPX4 levels at both the protein expression and mRNA levels using qPCR and Western blot analysis.

Results
Our results indicate that in melanoma, pharmacological and genetic inhibition of pigmentation affects sensitivity to ferroptosis. Consistent with these findings, we discovered that pigment production influences sensitivity to lipid peroxidation caused by ferroptosis compounds. Reduced levels of Glutathione and GPX4 in pigmented cells may lead to heightened sensitivity to ferroptosis.
Conclusion: Our results shed light on regulating ferroptosis through pigment production in melanoma cells. However, further studies are needed to understand the mechanism by which pigmentation modulates ferroptosis.

Funding:HCEMM Grant 2022-27, OTKA KFI Grant 2021-25, Lendület Grant (LP2024-12/2024)

University

Semmelweis University

Supervisor

Lajos Vince Kemény MD, PhD

Publication of my abstract

I do not give consent to the publication of my abstract on the website of the congress.

phd.section.field

in doctoral studies after complex exam (PhD)

Kind

Szabad

Status

elfogadva

Accepted presentation method

poszter

Előadás fájl jóváhagyás

nem rendelkezett róla

Előadó

7351

Start

14:42

End

14:48