Application of Mitochondrially Targeted Nanoconstructs to Neoadjuvant X-ray-Induced Photodynamic Therapy for Rectal Cancer

Photodynamic therapy (PDT) is a promising modern method for treatment of oncological, bacterial, fungal and viral diseases. However, its application is limited to diseases with superficial localization since the body tissues are not transparent for visible light. To address this problem and extend PDT application to abdominal diseases, an enhanced method of X-ray photodynamic therapy (XRPDT) is suggested, involving X-ray radiation easily penetrating the body tissues. The implementation of this approach requires the development of a pharmacological drug including a photosensitizer stimulated by visible light to yield active oxygen and a nanosized phosphor converting X-ray radiation into visible light with the wavelength required for the photosensitizer activation. This study is aimed at obtaining X-ray stimulated phosphors with nanosized particles suitable for XRPDT application. For this purpose, Y2O3:Eu phosphors were synthesized via hydrothermal processing of the corresponding mixed acetate followed by annealing. To prevent from the undesirable agglomeration of the particles in the course of hydrothermal synthesis and subsequent annealing, different techniques were used, including rapid thermal annealing (RTA), microwave annealing and addition of finely dispersed pyrogenic silica (aerosil) to the phosphor. The microwave annealing was carried out using a special installation including a resonance chamber for maintaining a standing wave of microwave radiation. The performed research allowed the determination of hydrothermal processing optimal duration affording the synthesis of phosphors with the highest luminescence brightness. The application of microwave annealing is found to provide phosphors with a more perfect crystal structure compared with RTA. The developed method of Y2O3:Eu phosphor synthesis involving pyrogenic silica addition to the autoclave allowed the preparation of samples with the amorphous structure and significantly reduced the particle size without a considerable decrease in the luminescence brightness. The particle size of the phosphor synthesized with aerosil addition is less than 100 nm that allows its implementation in pharmacological drugs for XRPDT.

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Super Long Green Persistent Luminescence from X-Ray Excited β-NaYF4: Tb3+

10.20944/preprints201902.0241.v1 ◽

2019 ◽

Cited By ~ 1

Author(s):

Yue Hu ◽

Yanmin Yang ◽

Xiaoxiao Li ◽

Xin Wang ◽

Yunqian Li ◽

...

Keyword(s):

Photodynamic Therapy ◽

Light Source ◽

Green Emission ◽

Persistent Luminescence ◽

Tunneling Model ◽

X Ray ◽

Long Afterglow ◽

Photo Stability ◽

F Centers

Here, we have discovered a X-ray excited long afterglow phosphor β-NaYF4: Tb3+. After the irradiation of X-ray, the green emission can persist for more than 240 h. After 36 h, the afterglow intensity arrived at 0.69 mcd•m-2, which can clearly be observed by naked eyes. Even after 84 h, the afterglow emission brightness still reached 0.087 mcd•m-2. Also, combined with the results of thermoluminescence and photoluminescence, the super long afterglow emission of β-NaYF4: Tb3+ can be ascribed to the tunneling model associated with F centers. More importantly, the super long green afterglow emission of β-NaYF4: Tb3+ has been successfully used as in vivo light source to activate g-C3N4 for photodynamic therapy（PDT）and bacteria destruction. Furthermore, super long persistent luminescence of β-NaYF4: Tb3+ could be repeatedly charged by X-ray for many circulations, which indicates that the phosphors have high photo stability under repeated cycles of alternating X-ray irradiation.

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Photodynamic Therapy for Advanced Rectal Cancer: A Case Report

Journal of Clinical and Nursing Research ◽

10.26689/jcnr.v4i6.1613 ◽

2020 ◽

Vol 4 (6) ◽

Author(s):

Lemei Chen ◽

Yanping Liu ◽

Ping Xie ◽

Huizhen Fan

Keyword(s):

Colorectal Cancer ◽

Rectal Cancer ◽

Photodynamic Therapy ◽

Palliative Treatment ◽

Treatment Process ◽

Advanced Colorectal Cancer ◽

Advanced Rectal Cancer ◽

Tumor Treatment ◽

Potential Value ◽

Case Data

Objective: To investigate the potential value of PDT(photodynamic therapy) in the treatment of rectal cancer by reviewing the diagnosis and treatment process of a patient with advanced rectal cancer who lost the opportunity of surgery. Methods: Select the case data of a patient receiving photodynamic therapy in our hospital, and analyze the photodynamic mechanism, safety and efficiency, and discuss the efficacy of photodynamic therapy. Results: After the patient received photodynamic therapy, re-examination of the endoscopy showed that the intestinal cavity was smoother than before, the bowel was difficult, and the symptoms of blood in the stool improved. Conclusion: Photodynamic therapy can be used as a radical or palliative treatment for clinical tumor treatment. Because of its advantages of minimally invasive, tissue-specific, repetitive and synergistic radiotherapy and chemotherapy, it plays an important role in early or middle-advanced colorectal cancer and is worthy of clinical promotion.

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Verteprofin conjugated to gold nanoparticles for fluorescent cellular bioimaging and X-ray mediated photodynamic therapy

Microchimica Acta ◽

10.1007/s00604-017-2145-z ◽

2017 ◽

Vol 184 (6) ◽

pp. 1765-1771 ◽

Cited By ~ 13

Author(s):

Sandhya Clement ◽

Wenjie Chen ◽

Ayad G. Anwer ◽

Ewa M. Goldys

Keyword(s):

Gold Nanoparticles ◽

Photodynamic Therapy ◽

X Ray

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Microfluidic Synthesis of Theranostic Nanoparticles with Near-Infrared Scintillation: Toward Next-Generation Dosimetry in X-ray-Induced Photodynamic Therapy

ACS Applied Materials & Interfaces ◽

10.1021/acsami.1c20689 ◽

2021 ◽

Author(s):

Mileni Isikawa ◽

Eder Guidelli

Keyword(s):

Photodynamic Therapy ◽

Near Infrared ◽

Next Generation ◽

X Ray ◽

Theranostic Nanoparticles

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Rare-Earth-Doped Calcium Carbonate Exposed to X-ray Irradiation to Induce Reactive Oxygen Species for Tumor Treatment

International Journal of Molecular Sciences ◽

10.3390/ijms20051148 ◽

2019 ◽

Vol 20 (5) ◽

pp. 1148 ◽

Cited By ~ 1

Author(s):

Chun-Chen Yang ◽

Wei-Yun Wang ◽

Feng-Huei Lin ◽

Chun-Han Hou

Keyword(s):

Reactive Oxygen Species ◽

Photodynamic Therapy ◽

Tumor Growth ◽

Light Source ◽

Reactive Oxygen ◽

Blood Analysis ◽

Oxygen Species ◽

Tumor Treatment ◽

X Ray

Conventional photodynamic therapy (PDT) is limited by its penetration depth due to the photosensitizer and light source. In this study, we developed X-ray induced photodynamic therapy that applied X-ray as the light source to activate Ce-doped CaCO3 (CaCO3:Ce) to generate an intracellular reactive oxygen species (ROS) for killing cancer cells. The A549 cell line was used as the in vitro and in vivo model to evaluate the efficacy of X-ray-induced CaCO3:Ce. The cell viability significantly decreased and cell cytotoxicity obviously increased with CaCO3:Ce exposure under X-ray irradiation, which is less harmful than radiotherapy in tumor treatment. CaCO3:Ce produced significant ROS under X-ray irradiation and promoted A549 cancer cell death. CaCO3:Ce can enhance the efficacy of X-ray induced PDT, and tumor growth was inhibited in vivo. The blood analysis and hematoxylin and eosin stain (H&E) stain fully supported the safety of the treatment. The mechanisms underlying ROS and CO2 generation by CaCO3:Ce activated by X-ray irradiation to induce cell toxicity, thereby inhibiting tumor growth, is discussed. These findings and advances are of great importance in providing a novel therapeutic approach as an alternative tumor treatment.

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