Hypericin-assisted photodynamic therapy against anaplastic thyroid cancer

Photodynamic therapy, used alone or in combination with chemotherapy, has given promising results in preclinical studies for thyroid cancer.

“Photodynamic therapy is a hope, which, used alone or in combination with previously used chemotherapy, gave promising results in preclinical studies. [6-10].”

In mouse study group, tumor weight and volume were almost completely reduced after HYP-PDT; tumors in control groups gradually increased.

“In the mouse study group, tumor weight and volume were almost completely reduced. The tumors in the control groups gradually increased.”

In vitro studies by Hyejin Kim using HYP as PS showed absorption peak of HYP was 593 nm, and absorption degree was directly proportional to HYP concentration.

“In vitro studies conducted by Hyejin Kim and colleagues using HYP as PS showed that the absorption peak of HYP was 593 nm, and the degree of absorption was directly proportional to the HYP concentration, making it a suitable potential PS.”

Previous studies have shown hypericin efficacy in treatment of anaplastic thyroid cancer, mainly by stimulating cancer cell apoptosis and mitochondrial damage.

“Previous studies have shown its efficacy in the treatment of anaplastic thyroid cancer, mainly by stimulating cancer cell apoptosis and mitochondrial damage. [6,9]”

In the study group subjected to HYP-PDT, compared to controls (HYP only, laser only, no treatment), there was a large number of induced cell death, significantly increased intracellular ROS, and significantly decreased mitochondrial membrane potential.

“The study group, i.e. subjected to PDT using HYP, compared to the control groups, i.e. exposed to HYP only, laser only or no treatment at all, was characterized by a large number of induced cell death, significantly increased intracellular ROS and significantly decreased mitochondrial membrane potential.”

Viability of anaplastic cancer cell lines under HYP-PDT decreased significantly in an amount dependent on HYP concentration, more pronounced up to 10 μg/ml.

“The viability of anaplastic cancer cell lines under the influence of PDT using HYP decreased significantly, in an amount dependent on the HYP concentration, and this correlation was more pronounced up to a HYP concentration of 10 μ g/ml.”

On day 4 of the study, necrosis was observed in skin exposed to HYP-PDT, while skin in control group using only laser remained intact.

“On day 4 of the study, necrosis was observed in the skin that was exposed to HYP-PDT, while the skin in the control group using only laser remained intact.”

The most commonly used photosensitizers in PDT for thyroid cancers include hypericin, porphyrin, photophrin, radachlorin, and 5-aminolevulinic acid (ALA).

“The most commonly used PS in PDT for the treatment of thyroid cancers include hypericin, porphyrin, photophrin, radachlorin, and 5-aminolevulinic acid (ALA). [8-10,14,32]”