Microendoscopy for hypericin fluorescence tumor diagnosis in a subcutaneous glioma mouse model

Noell, Susan; Feigl, Guenther C.; Serifi, Dzenan; Mayer, Daniel; Naumann, Ulrike; Göbel, Werner; Ehrhardt, André; Ritz, Rainer

doi:10.1016/j.pdpdt.2013.06.001

Cited by 9 publications

(3 citation statements)

References 25 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…To verify the potential to detect intracerebral gliomas using microendoscopy, tumor cells were also implanted into the brain. After craniotomy, hypericin fluorescence was detected in intracerebral and extracranial gliomas and also in the vessels located in the cortical surface of the contralateral hemisphere (Noell et al, 2013 ) (Table 4 ).…”

Section: Light-activated Hypericinmentioning

confidence: 99%

Hypericin in the Light and in the Dark: Two Sides of the Same Coin

et al. 2016

View full text Add to dashboard Cite

Hypericin (4,5,7,4′,5′,7′-hexahydroxy-2,2′-dimethylnaphtodianthrone) is a naturally occurring chromophore found in some species of the genus Hypericum, especially Hypericum perforatum L. (St. John's wort), and in some basidiomycetes (Dermocybe spp.) or endophytic fungi (Thielavia subthermophila). In recent decades, hypericin has been intensively studied for its broad pharmacological spectrum. Among its antidepressant and light-dependent antiviral actions, hypericin is a powerful natural photosensitizer that is applicable in the photodynamic therapy (PDT) of various oncological diseases. As the accumulation of hypericin is significantly higher in neoplastic tissue than in normal tissue, it can be used in photodynamic diagnosis (PDD) as an effective fluorescence marker for tumor detection and visualization. In addition, light-activated hypericin acts as a strong pro-oxidant agent with antineoplastic and antiangiogenic properties, since it effectively induces the apoptosis, necrosis or autophagy of cancer cells. Moreover, a strong affinity of hypericin for necrotic tissue was discovered. Thus, hypericin and its radiolabeled derivatives have been recently investigated as potential biomarkers for the non-invasive targeting of tissue necrosis in numerous disorders, including solid tumors. On the other hand, several light-independent actions of hypericin have also been described, even though its effects in the dark have not been studied as intensively as those of photoactivated hypericin. Various experimental studies have revealed no cytotoxicity of hypericin in the dark; however, it can serve as a potential antimetastatic and antiangiogenic agent. On the contrary, hypericin can induce the expression of some ABC transporters, which are often associated with the multidrug resistance (MDR) of cancer cells. Moreover, the hypericin-mediated attenuation of the cytotoxicity of some chemotherapeutics was revealed. Therefore, hypericin might represent another St. John's wort metabolite that is potentially responsible for negative herb–drug interactions. The main aim of this review is to summarize the benefits of photoactivated and non-activated hypericin, mainly in preclinical and clinical applications, and to uncover the “dark side” of this secondary metabolite, focusing on MDR mechanisms.

show abstract

Section: Light-activated Hypericinmentioning

confidence: 99%

Hypericin in the Light and in the Dark: Two Sides of the Same Coin

et al. 2016

View full text Add to dashboard Cite

show abstract

“…In humans, hypericin has been used for the treatment of various conditions including depression, anxiety, restlessness, and sleeping disorders [ 80 , 81 ]. Moreover, its fluorescent properties have enabled the visualization of malignant tumors such as gliomas in a process known as photodiagnosis [ 82 , 83 , 84 ]. In addition, its photosensitizing properties have been widely used in treating several cancers (GH4C1 rat adenoma, human P3 squamous carcinoma cells, head and neck cancer, and melanoma) [ 8 , 85 , 86 , 87 , 88 ].…”

Section: Introductionmentioning

confidence: 99%

Antibody-Based Immunotherapy: Alternative Approaches for the Treatment of Metastatic Melanoma

et al. 2020

View full text Add to dashboard Cite

Melanoma is the least common form of skin cancer and is associated with the highest mortality. Where melanoma is mostly unresponsive to conventional therapies (e.g., chemotherapy), BRAF inhibitor treatment has shown improved therapeutic outcomes. Photodynamic therapy (PDT) relies on a light-activated compound to produce death-inducing amounts of reactive oxygen species (ROS). Their capacity to selectively accumulate in tumor cells has been confirmed in melanoma treatment with some encouraging results. However, this treatment approach has not reached clinical fruition for melanoma due to major limitations associated with the development of resistance and subsequent side effects. These adverse effects might be bypassed by immunotherapy in the form of antibody–drug conjugates (ADCs) relying on the ability of monoclonal antibodies (mAbs) to target specific tumor-associated antigens (TAAs) and to be used as carriers to specifically deliver cytotoxic warheads into corresponding tumor cells. Of late, the continued refinement of ADC therapeutic efficacy has given rise to photoimmunotherapy (PIT) (a light-sensitive compound conjugated to mAbs), which by virtue of requiring light activation only exerts its toxic effect on light-irradiated cells. As such, this review aims to highlight the potential clinical benefits of various armed antibody-based immunotherapies, including PDT, as alternative approaches for the treatment of metastatic melanoma.

show abstract

“…[21] Finally, hypericin was considered as an antimicrobial agent, antioxidant, and as a promising candidate for photodynamic diagnosis. [22,23] Recently, investigations on the pharmaceutical and clinical purposes of hypericin surged, and Hypericum perforatum as a source of hypericin has gradually become one of the three most popular Chinese herbal medicines. [24] The aim of this review is to describe the recent advances on hypericin research, focusing on biosynthesis, chemical synthesis, analysis, extraction, purification, photosensitivity, solubility in water and stability.…”

Section: Introductionmentioning

confidence: 99%

Hypericin: Source, Determination, Separation, and Properties

Zhang

Gao

et al. 2020

Separation & Purification Reviews

View full text Add to dashboard Cite

Hypericin is a naturally occurring compound synthesized by certain species of the genus Hypericum, with various pharmacological effects. It is used as a natural photosensitizing agent with great potential in photodynamic therapy. This review discusses the latest results about the biosynthetic pathways and chemical synthetic routes to obtain hypericin. Although many analysis methods can be used for the determination of hypericin purity, HPLC has become the method of choice due to its fast and sensitive analyses. The extraction and purification of hypericin are also described. Hypericin can be used as a photosensitizer due to a large and active π-electron conjugated system in its structure. Medical applications of hypericin are not easy due to several unsolved practical problems, which include hypericin phototoxicity, poor solubility in water, and extreme sensitivity to light, heat, and pH.

show abstract

Microendoscopy for hypericin fluorescence tumor diagnosis in a subcutaneous glioma mouse model

Cited by 9 publications

References 25 publications

Hypericin in the Light and in the Dark: Two Sides of the Same Coin

Hypericin in the Light and in the Dark: Two Sides of the Same Coin

Antibody-Based Immunotherapy: Alternative Approaches for the Treatment of Metastatic Melanoma

Hypericin: Source, Determination, Separation, and Properties

Contact Info

Product

Resources

About