Effect of Photosensitiser Chlorin E6 on Cancerous Bone Tumor Cells Using Photodynamic Therapy

Photodynamic therapy (PDT) is a minimally invasive method used in the treatment of various cancers and skin diseases, but it is not widely used in bone cancer, where the current therapy is often not effective and accompanied by side effects. Alternative and more effective therapies like PDT are needed. In this in-vitro study, the effect of the photosensitizer (PS) chlorin e6 (Ce6) on cancerous bone tumor cells using PDT was examined.

A total of 27 tissue specimens from patients with primary bone cancers or bone metastases of different origins were genetically characterized and treated with PDT. Following a 24-h incubation, cell viability was determined, and the effect of PDT on cell migration was analyzed over 48 h.

We could demonstrate that the effect on proliferation of PDT in combination with the PS Ce6 was best in cells isolated from primary osteosarcoma and in bone metastases from mammary carcinomas. Besides proliferation, PDT was also effective in inhibiting the migration of these cells. A statistically significant correlation between the PDT effect and CD164 gene expression was detected, indicating that a high expression of this gene could result in a higher effectiveness of the photodynamic treatment.

This study analyzes for the first time the effect of PDT in bone cancers and metastases and shows the potential of treating these cancer types with Ce6 PDT.