What NIR photodynamic activation offers molecular targeted nanomedicines: Perspectives into the conundrum of tumor specificity and selectivity

Biomimetic Nanotechnology: A Natural Path Forward for Tumor-Selective and Tumor-Specific NIR Activable Photonanomedicines

“…As mentioned in Section 1 , NIR activable PNMs are activated by photodynamic processes, which also serve as the foundation for anticancer PDT. While PNMs can contain various PS molecules that are activable by light spanning the UV–visible–NIR spectrum, NIR activable PNMs are particularly attractive due to their tissue-penetrating properties at such wavelengths that lie within the optical windows of biological tissue [ 3 ]. Visudyne is the first and only PNM approved by the FDA to date which comprises a lipid-based PNM that contains the NIR activable photosensitizer benzoporphyrin derivative (BPD).…”

“…An example of the PDT mechanism of action using bPNMs is depicted in Figure 3 A, in addition to how bPNMs can improve tumor photodestruction ( Figure 3 B), prolong mouse survival ( Figure 3 C) and enhance cancer cell apoptosis in tumor tissue following NIR activation ( Figure 3 D). We have previously reported on the powerful attributes of NIR photodynamic activation in the processes that underly the tumor selectivity and tumor specificity of PNMs [ 3 ]. In this section, a comprehensive discussion of all NIR activable bPNMs reported to date has been included with special emphasis made on how such approaches have achieved tumor-selective and tumor-specific photodestruction.…”

“…Furthermore, irrespective of the type of synthetic nanomaterial used, delivery of nanomedicines to tumors appears to reach a plateau [ 2 ], whereby further physiological modulation of tumors is required to augment the accumulation and permeation of nanomedicines. Such approaches for physiological modulation include pharmacological vascular and stromal disrupting agents, radiation therapy, focused ultrasound and PDT [ 3 , 4 , 5 , 6 , 7 ]. Given this major bottleneck in synthetic nanomedicines (including PNMs), biomimetic nanotechnology has emerged as an attractive alternative platform for drug delivery.…”

“…This review will focus on the unique attributes of biomimetic nanotechnology that allow biomimetic PNMs (bPNMs) to exhibit pronounced tumor selectivity (preferential tumor accumulation) in addition to tumor specificity—discrete molecular affinity for cancer cells through a process known as homotypic recognition [ 3 ]. Both tumor selectivity and tumor specificity, being critical for the safety and efficacy of PDT-based combination therapies, hold significant promise as the next generation of nanomedicines in the clinical arena [ 3 ]. Figure 1 is a graphical depiction of how bPNMs are capable of exhibiting both tumor specificity and tumor selectivity in solid tumors, which also clarifies the distinction between both concepts.…”

“…Figure 1 is a graphical depiction of how bPNMs are capable of exhibiting both tumor specificity and tumor selectivity in solid tumors, which also clarifies the distinction between both concepts. We have previously described in depth how molecular targeted PNMs can exhibit both tumor selectivity (an attribute of nanomedicines) and tumor specificity (an attribute of personalized molecular targeted medicines), and we have conceptually delineated the differences between both concepts [ 3 ].…”