Effect of Photodynamic Therapy with Chlorin e6 on Canine Tumors

Abstract

This work aims to prepare pure Chlorin e6 (Ce6) and establish Ce6-mediated photodynamic therapy (Ce6-PDT) as a better therapy option for canine tumors as well as mouse tumor models. Five dogs suffering from various cancers were treated with Ce6-PDT from one to several times. After receiving the Ce6 (2.5 mg/kg) for 3 h, tumors were illuminated superficially or interstitially with 660 nm light. Two dogs underwent Ce6-guided fluorescence imaging by photodynamic diagnosis (PDD). Cell proliferation and apoptosis were detected by the 4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay and western blot assay, respectively. Ce6-PDT efficacy was also determined using melanoma and pancreatic cancer mouse models. Two veterinary patients with mammary carcinoma and histiocytic sarcoma had their tumors significantly diminished and showed improved health after receiving Ce6-PDT. Moreover, in the cases of canine tumors, the adjunctive use of Ce6-PDD revealed cancers that were not visible with white light viewing and provided a visual contrast from surrounding tissues. Also, in vivo, Ce6-PDT remarkably reduced melanoma and pancreatic tumors in the mouse model. These findings could pave the way for a better understanding of the underlying processes of Ce6-PDT, making it an effective and safe candidate for use in human and veterinary applications to abolish various cancers.

Anti-Obesity Effect of Chlorin e6-Mediated Photodynamic Therapy on Mice with High-Fat-Diet-Induced Obesity

“…Obesity is considered an epidemic that is rapidly spreading across the globe and causing a variety of metabolic diseases [ 1 ]. In recent years, PDT has become an alternative choice for individuals to reduce their weight amidst the hustle of life, besides various therapeutic treatments for obesity and its related metabolic disorders [ 26 , 27 , 28 , 29 , 30 ]. For the first time, the two different murine models of obesity investigated the pharmacokinetic properties and ADME studies as well as evaluated the anti-obesity effects of Ce6-PDT by using PDT chamber systems.…”

“…In the present work, we have used the Ce6 prepared in-house by the previously reported method [ 30 ]. The lyophilized powder of Ce6-PVP in the ratio of 1:1 (Phonozen ® , Dongsung Biopharmaceutical, Seoul, Republic of Korea) was prepared, which was then dissolved in normal saline to make the desired concentration prior to oral administration.…”

“…After receiving the remarkable results of Ce6-mediated PDT for cancer treatments [ 30 , 31 , 32 ], we introduced Ce6-PDT for the first time for its anti-obesity activities in vivo. In an earlier study, we demonstrated the potential inhibitory roles of Ce6-PDT on adipogenesis and lipogenesis in 3T3-L1 cells [ 33 ].…”

Single-Cell RNA Sequencing Reveals Immuno-Oncology Characteristics of Tumor-Infiltrating T Lymphocytes in Photodynamic Therapy-Treated Colorectal Cancer Mouse Model

“…Ce6 complexed with polyvinylpyrrolidone (PVP) (Ce6-PVP complex), designated Phonozen ® , was obtained from DongSung BioPharmaceuticals (Daegu, Republic of Korea) and synthesized as described previously [ 17 , 18 ]. Briefly, Spirulina platensis (SP) was provided by the East India Distilleries Parry (EID Parry, Chennai, India).…”

“…Previously, PDT treatment developed by DongSung BioPharmaceuticals significantly reduced tumor growth in B16F10 melanoma allograft tumors and PANC02 pancreatic tumors in mice [ 17 , 18 ]. In this study, we examined the immuno-oncological characteristics of tumor-infiltrating T lymphocytes in a photodynamic therapy-treated CRC mouse model.…”