scholarly journals Enzyme-Responsive Materials as Carriers for Improving Photodynamic Therapy

2021 ◽  
Vol 9 ◽  
Author(s):  
Houhe Liu ◽  
Fanwen Yang ◽  
Wenjie Chen ◽  
Teng Gong ◽  
Yi Zhou ◽  
...  
Keyword(s):  
Reactive Oxygen Species ◽  
Photodynamic Therapy ◽  
Side Effects ◽  
Clinical Application ◽  
Smart Materials ◽  
Therapeutic Effects ◽  
Oxygen Species ◽  
Responsive Materials ◽  
Normal Tissues ◽  
Tumor Tissues

Photodynamic therapy (PDT) is a mini-invasive therapy on malignancies via reactive oxygen species (ROS) induced by photosenitizer (PS) upon light irradiation. However, poor target of PS to tumor limits the clinical application of PDT. Compared with normal tissues, tumor tissues have a unique enzymatic environment. The unique enzymatic environment in tumor tissues has been widely used as a target for developing smart materials to improve the targetability of drugs to tumor. Enzyme-responsive materials (ERM) as a smart material can respond to the enzymes in tumor tissues to specifically deliver drugs. In PDT, ERM was designed to react with the enzymes highly expressed in tumor tissues to deliver PS in the target site to prevent therapeutic effects and avoid its side-effects. In the present paper, we will review the application of ERM in PDT and discuss the challenges of ERM as carriers to deliver PS for further boosting the development of PDT in the management of malignancies.

scholarly journals PHOTODYNAMIC THERAPY: NEW LIGHT IN MEDICINE WORLD

2010 ◽  
Vol 8 (2) ◽  
pp. 279-291 ◽  
Author(s):  
Venny Santosa ◽  
Leenawaty Limantara
Keyword(s):  
Reactive Oxygen Species ◽  
Photodynamic Therapy ◽  
Side Effects ◽  
Reactive Oxygen Species Generation ◽  
Reactive Oxygen ◽  
Type I ◽  
Oxygen Species ◽  
Type Ii ◽  
Light Spectrum ◽  
Medical Field

Photodynamic therapy (PDT) is a considerably new kind of photochemotherapeutic treatment in medical field. It combines the use of three components, which are a photosensitizer, light and oxygen. Photosensitizer is a compound activated by light. The application can be oral, topical or intravenous. It usually member of porphyrin group with ampiphilic characteristics. Photosensitizer can be of generation I, II or III, each generation step develops more specificity, selectivity and deeper tissue application. This review will discuss photosensitizer development consecutively, with its benefit and lackness. The light used is usually on red region, while the oxygen is involved in reactive oxygen species generation. Its mechanism action can go through either in type I or type II reaction. This kind of therapy is usually being used in oncology, especially in superficial and in-lining cancers, dermatology and ophthalmology field. This therapy can be safely given to patients with complication and has distinct advantages compare with other treatment such as chemotherapy and surgery. It also considerably has lesser side effects and risks. Broader application is being developed through various experiments and photosensitizer modification.   Keywords: light spectrum, photoactivation, photodynamic therapy, photosensitizer

scholarly journals Melatonin as a Radio-Sensitizer in Cancer

Biomedicines ◽  
2020 ◽  
Vol 8 (8) ◽  
pp. 247
Author(s):  
Carolina Alonso-González ◽  
Alicia González ◽  
Javier Menéndez-Menéndez ◽  
Carlos Martínez-Campa ◽  
Samuel Cos
Keyword(s):  
Side Effects ◽  
Tumor Cells ◽  
Cancer Growth ◽  
Therapeutic Effects ◽  
Oxygen Species ◽  
Normal Cells ◽  
Normal Tissues ◽  
Species Production ◽  
Estrogen Biosynthesis ◽  
Stimulation Of

Radiotherapy is one of the treatments of choice in many types of cancer. Adjuvant treatments to radiotherapy try, on one hand, to enhance the response of tumor cells to radiation and, on the other hand, to reduce the side effects to normal cells. Radiosensitizers are agents that increase the effect of radiation in tumor cells by trying not to increase side effects in normal tissues. Melatonin is a hormone produced mainly by the pineal gland which has an important role in the regulation of cancer growth, especially in hormone-dependent mammary tumors. Different studies have showed that melatonin administered with radiotherapy is able to enhance its therapeutic effects and can protect normal cells against side effects of this treatment. Several mechanisms are involved in the radiosensitization induced by melatonin: increase of reactive oxygen species production, modulation of proteins involved in estrogen biosynthesis, impairment of tumor cells to DNA repair, modulation of angiogenesis, abolition of inflammation, induction of apoptosis, stimulation of preadipocytes differentiation and modulation of metabolism. At this moment, there are very few clinical trials that study the therapeutic usefulness to associate melatonin and radiotherapy in humans. All findings point to melatonin as an effective adjuvant molecule to radiotherapy in cancer treatment.

scholarly journals Porphylipoprotein Accumulation and Porphylipoprotein Photodynamic Therapy Effects Involving Cancer Cell-Specific Cytotoxicity

2021 ◽  
Vol 22 (14) ◽  
pp. 7306
Author(s):  
Hiromi Kurokawa ◽  
Hiromu Ito ◽  
Hirofumi Matsui
Keyword(s):  
Reactive Oxygen Species ◽  
Photodynamic Therapy ◽  
Cancer Cell ◽  
Reactive Oxygen ◽  
Cancer Tissue ◽  
Oxygen Species ◽  
Normal Tissues ◽  
Specific Cytotoxicity ◽  
Specific Accumulation

In photodynamic therapy (PDT) for neoplasms, photosensitizers selectively accumulate in cancer tissue. Upon excitation with light of an optimal wavelength, the photosensitizer and surrounding molecules generate reactive oxygen species, resulting in cancer cell-specific cytotoxicity. Porphylipoprotein (PLP) has a porphyrin-based nanostructure. The porphyrin moiety of PLP is quenched because of its structure. When PLP is disrupted, the stacked porphyrins are separated into single molecules and act as photosensitizers. Unless PLP is disrupted, there is no photosensitive disorder in normal tissues. PLP can attenuate the photosensitive disorder compared with other photosensitizers and is ideal for use as a photosensitizer. However, the efficacy of PLP has not yet been evaluated. In this study, the mechanism of cancer cell-specific accumulation of PLP and its cytotoxic effect on cholangiocarcinoma cells were evaluated. The effects were investigated on normal and cancer-like mutant cells. The cytotoxicity effect of PLP PDT in cancer cells was significantly stronger than in normal cells. In addition, reactive oxygen species regulated intracellular PLP accumulation. The cytotoxic effects were also investigated using a cholangiocarcinoma cell line. The cytotoxicity of PLP PDT was significantly higher than that of laserphyrin-based PDT, a conventional type of PDT. PLP PDT could also inhibit tumor growth in vivo.

356 Genetic variation in relation to adverse side-effects of radiotherapy – focus on the metabolism of reactive oxygen species

2010 ◽  
Vol 8 (3) ◽  
pp. 161
Author(s):  
H. Edvardsen ◽  
K.V. Reinertsen ◽  
G.I. Grenaker Alnæs ◽  
A. Tsalenko ◽  
J. Alsner ◽  
...  
Keyword(s):  
Reactive Oxygen Species ◽  
Genetic Variation ◽  
Side Effects ◽  
Reactive Oxygen ◽  
Oxygen Species ◽  
Adverse Side Effects

scholarly journals Liposome Photosensitizer Formulations for Effective Cancer Photodynamic Therapy

Pharmaceutics ◽  
2021 ◽  
Vol 13 (9) ◽  
pp. 1345
Author(s):  
Sherif Ashraf Fahmy ◽  
Hassan Mohamed El-Said Azzazy ◽  
Jens Schaefer
Keyword(s):  
Reactive Oxygen Species ◽  
Photodynamic Therapy ◽  
Adverse Effects ◽  
Cellular Uptake ◽  
Treatment Effectiveness ◽  
State Of The Art ◽  
Oxygen Species ◽  
Chemotherapeutic Drugs ◽  
Invasive Strategy ◽  
Non Invasive

Photodynamic therapy (PDT) is a promising non-invasive strategy in the fight against that which circumvents the systemic toxic effects of chemotherapeutics. It relies on photosensitizers (PSs), which are photoactivated by light irradiation and interaction with molecular oxygen. This generates highly reactive oxygen species (such as 1O2, H2O2, O2, ·OH), which kill cancer cells by necrosis or apoptosis. Despite the promising effects of PDT in cancer treatment, it still suffers from several shortcomings, such as poor biodistribution of hydrophobic PSs, low cellular uptake, and low efficacy in treating bulky or deep tumors. Hence, various nanoplatforms have been developed to increase PDT treatment effectiveness and minimize off-target adverse effects. Liposomes showed great potential in accommodating different PSs, chemotherapeutic drugs, and other therapeutically active molecules. Here, we review the state-of-the-art in encapsulating PSs alone or combined with other chemotherapeutic drugs into liposomes for effective tumor PDT.

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