Breast cancer as photodynamic therapy target: Enhanced therapeutic efficiency by overview of tumor complexity

Abstract

Photodynamic therapy is a minimally invasive and clinically approved procedure for eliminating selected malignant cells with specific light activation of a photosensitizer agent. Whereas interstitial and intra-operative approaches have been investigated for the ablation of a broad range of superficial or bulky solid tumors such as breast cancer, the majority of approved photodynamic therapy protocols are for the treatment of superficial lesions of skin and luminal organs. This review article will discuss recent progress in research focused mainly on assessing the efficacies of various photosensitizers used in photodynamic therapy, as well as the combinatory strategies of various therapeutic modalities for improving treatments of parenchymal and/or stromal tissues of breast cancer solid tumors. Cytotoxic agents are used in cancer treatments for their effect on rapidly proliferating cancer cells. However, such therapeutics often lack specificity, which can lead to toxicity and undesirable side effects. Many approaches are designed to target tumors. Selective therapies can be established by focusing on distinctive intracellular (receptors, apoptotic pathways, multidrug resistance system, nitric oxidemediated stress) and environmental (glucose, pH) differences between tumor and healthy tissue. A rational design of effective combination regimens for breast cancer treatment involves a better understanding of the mechanisms and molecular interactions of cytotoxic agents that underlie drug resistance and sensitivity. Key words: Photodynamic therapy; Breast cancer; Tumor microenvironment; Treatment combination; Synergism Core tip: Breast cancer is the most common cancer in women worldwide. However, effective therapies that reduce the high mortality rate and improve patient quality of life are still unavailable. In recent years, the use of photodynamic therapy has been examined for use in breast cancer treatment. Photodynamic therapy provides a new and promising antitumor strategy that could be implemented, alone or in combination with other approved or experimental therapeutic approaches, to a wide range of applications.

Photodynamic treatment with anionic nanoclays containing curcumin on human triple‐negative breast cancer cells: Cellular and biochemical studies

“…So, there is a need to develop not only effective therapies to reduce the mortality arising, but also increase the life quality of patients. [32][33][34] . In fact, common treatments like drugs and hormone therapy that target receptors are ineffective for this kind of breast cancer.…”

Photodynamic therapy in cancer treatment - an update review

“…These photosensitizers have shown selectivity towards tumor cells and are ideal for cellular and vascular-targeted PDT. Moreover their interference with cytoprotective molecular responses constitutes an area of growing interest [22,23] . Other compounds such as porphyrin precursors [e.g., aminolevulinic acid (ALA)] [24] , phenothiazines (e.g., methylene blue) [25,26] , cyanines (e.g., merocyanine, indocyanine green) [27] , hypericin [28] , and xanthenes (e.g., Rose Bengal) [29] have been considered as good candidates as PS used for PDT.…”

Photodynamic therapy for solid tumors: A review of the literature

“…For primary breast cancers, preclinical PDT data have been promising. In some in vitro and in vivo studies, PDT has been combined with radiation, chemotherapy, immune‐modulating agents, and receptor‐targeted agents, with synergistic effects . Animal models suggest that PDT may be effective for spinal metastases .…”

“…In some in vitro and in vivo studies, PDT has been combined with radiation, chemotherapy, immune-modulating agents, and receptor-targeted agents, with synergistic effects. 70,71 Animal models suggest that PDT may be effective for spinal metastases. 72 A Phase I/IIa clinical trial for PDT in primary breast cancer was completed in 2017, though no study results have yet been posted.…”