Targeted photodynamic therapy — a promising strategy of tumor treatment

Abstract

Targeted therapy is a new promising therapeutic strategy, created to overcome growing problems of contemporary medicine, such as drug toxicity and drug resistance. An emerging modality of this approach is targeted photodynamic therapy (TPDT) with the main aim of improving delivery of photosensitizer to cancer tissue and at the same time enhancing specificity and efficiency of PDT. Depending on the mechanism of targeting, we can divide the strategies of TPDT into "passive", "active" and "activatable", where in the latter case the photosensitizer is activated only in the target tissue. In this review, contemporary strategies of TPDT are described, including new innovative concepts, such as targeting assisted by peptides and aptamers, multifunctional nanoplatforms with navigation by magnetic field or "photodynamic molecular beacons" activatable by enzymes and nucleic acid. The imperative of introducing a new paradigm of PDT, focused on the concepts of heterogeneity and dynamic state of tumor, is also called for.

PDGFRβ-specific affibody-directed delivery of a photosensitizer, IR700, is efficient for vascular-targeted photodynamic therapy of colorectal cancer

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“…Clearly targeting [80] and combination therapies [81] are main area where we need PS improvement. Esp.…”

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“…Some of them use nanoparticles to do it. [7] Modification of the natural porphyrins by introduction of the terpene fragment on the periphery of the macrocycle can be very prospective because terpene derivatives express different bioactivity often based on different interactions with biomembranes. For example, the compounds that contain cyclobutane and cyclopropane rings are anti-viral and anti-germ compounds, neurotics and analgetics.…”