Characterisation of collagen type I matrices for pathophysiologically relevant spatial cancer cell cultures.

Specific cues provided to cells by the extracellular matrix (ECM) are determined by its composition. Except of collagens other naturally occurring ECM components should be considered in designing 3D models of diseases. We used spectrophotometric and rheological measurements and confocal imaging to characterise collagen matrices of human origin that can be modified by clinically relevant ECM components.

Suppression of resistance to aminolevulinic acid-based photodynamic therapy in esophageal cell lines by administration of iron chelators in collagen type I matrices.

Purpose: Photodynamic therapy (PDT) utilizes visible light to activate the cytotoxic effects of photosensitizing drugs. PDT protocols require optimization to overcome treatment resistance and induce a beneficial anti-tumor immune response. The aim of this study was to examine the possibility to suppress the resistance of esophageal cell lines to aminolevulinic acid (ALA)-PDT by administration of iron chelators to induce sufficient cell cytotoxicity under pathophysiologically relevant conditions, mimicking the advanced stages of cancer.

Modulation of aminolevulinic acid-based photoinactivation efficacy by iron in vitro is cell type dependent.

Iron availability to cells may be modified in the tumour microenvironment, which may be involved in treatment response. Iron availability affects the conversion of protoporphyrin IX to heme, which likely determines the efficacy of aminolevulinic acid-based photodynamic therapy (ALA-based PDT). We compared photoinactivation efficacy in three oesophageal cell lines in culture media differing in iron content, DMEM and RPMI 1640, and in RPMI 1640 supplemented with iron to understand the importance of iron presence for ALA-based PDT outcome.