Title:Targeting Microenvironment of Melanoma and Head and Neck Cancers
in Photodynamic Therapy
Volume: 29
Issue: 18
Author(s): Ivana Ratkaj, Martina Mušković and Nela Malatesti*
Affiliation:
- Department of Biotechnology, University of Rijeka, Rijeka, Croatia
Keywords:
Photodynamic therapy, photosensitisers, tumour microenvironment, hypoxia, melanoma, head and neck cancer.
Abstract:
Background: Photodynamic therapy (PDT), in comparison to other skin cancers,
is still far less effective for melanoma, due to the strong absorbance and the role of
melanin in cytoprotection. The tumour microenvironment (TME) has a significant role in
tumour progression, and the hypoxic TME is one of the main reasons for melanoma progression
to metastasis and its resistance to PDT. Hypoxia is also a feature of solid tumours
in the head and neck region that indicates negative prognosis.
Objective: The aim of this study was to individuate and describe systematically the main
strategies in targeting the TME, especially hypoxia, in PDT against melanoma and head
and neck cancers (HNC), and assess the current success in their application.
Methods: PubMed was used for searching, in MEDLINE and other databases, for the
most recent publications on PDT against melanoma and HNC in combination with the
TME targeting and hypoxia.
Results: In PDT for melanoma and HNC, it is very important to control hypoxia levels,
and amongst the different approaches, oxygen self-supply systems are often applied. Vascular
targeting is promising, but to improve it, optimal drug-light interval, and formulation
to increase the accumulation of the photosensitiser in the tumour vasculature, have to
be established. On the other side, the use of angiogenesis inhibitors, such as those interfering
with VEGF signalling, is somewhat less successful than expected and needs to be
further investigated.
Conclusion: The combination of PDT with immunotherapy by using multifunctional nanoparticles
continues to develop and seems to be the most promising for achieving a
complete and lasting antitumour effect.