Cell lines

Human alveolar adenocarcinoma cells A549

Preparation Method

The 96-well plates were treated with 50μL of agar solution (1.5%(w/v)) made in serum free Dulbecco’s Modified Eagle’s Medium. A549 cells(1×10⁴/well) were seeded in 96-well plates, centrifuged at 1500rcf for 15min at 25℃. The spheroids of 400-500μm size obtained after 4-5 days were utilized for the study

Reaction Conditions

3μg/mL for 4h(Growth Inhibition, Live/Dead Cell Assay), a serial concentration for 12h(0.5-3μg/mL In Vitro Phototoxicity)

Applications

A549 3D spheroids treated with Chlorin e6 micelles showed significant inhibition in growth, enhanced phototoxicity, and cellular apoptosis in comparison to free Chlorin e6.

Animal models

SCC-7 tumor-bearing mice（1×10⁶SCC-7 cells(80μL) were injected into the left femoral regions of 4-week-old C3H/HeN male mice）

Preparation Method

Free Chlorin e6, and gelatin-Chlorin e6 solution were injected into the tail vein when the tumor volume reached approximately 150±30mm3. At 4 and 12h after the sample injection, the tumor site of each mouse was irradiated with a red laser (658nm, 0.3W, 200J). Then, the tumor sizes of all mice were monitored over 14 days.

Dosage form

Free Chlorin e6, gelatin-Ce6 2μM, or gelatin-Ce6 8μM solution, each containing 2.5mg/kg of Chlorin e6

Applications

In vivo tumor accumulation of gelatin-Chlorin e6-2 was much higher than that of free Chlorin e6 or gelatin-Chlorin e6-8 after intravenous injection into mice. After laser irradiation to the tumor site, gelatin-Chlorin e6-2 showed superior tumor suppression, indicating an enhanced PDT effect.

• J Exp Clin Canc Res 41.1 (2022): 1-17. PMID: 35501823

Chlorin e6(Ce6) is a second-generation photosensitizer. Compared to the first-generation photosensitizers, Chlorin e6 has the advantage of efficiently absorbing longer light wavelengths, which is favorable for deeper tissue penetration^[1].Chlorin e6-based photosensitizers are widely used in antitumor photodynamic therapy(PDT) due to high quantum output of single oxygen and a strong absorption band in a red region^[2]

Chlorin e6-mediated PDT inhibits adipocyte differentiation and lipogenesis via regulating AMPK in 3T3-L1 cells, indicated that Chlorin e6-mediated PDT might serve as a potential therapy for the treatment of obesity and obesity-associated diseases^[2]. Chlorin e6-Fu/AL@GG hydrogel can be a feasible nanocarrier for Chlorin e6-assisted PDT that possesses an excellent capability to selectively kill colon cancer cells^[3]

Chlorin e6-loaded PEG-PCL nanoemulsions (Ce6-PCL-NEs) showed efficient cellular uptake and, upon laser irradiation, generated singlet oxygen to kill tumor cells. Particularly, Chlorin e6-PCL-NEs showed prolonged blood circulation and about 60% increased tumor accumulation compared to free Chlorin e6 after intravenous injection to 4T1 tumor-bearing mice(2.5mg/kg), indicated the promising potential of Chlorin e6-PCL-NEs for efficient PDT and in vivo drug delivery to tumor tissue^[4]. Chlorin e6 nano-precipitations (Chlorin e6 NPs) can be prepared by a one-pot method for effective photodynamic therapy of colorectal cancer. The HT-29 tumour-bearing mice were randomly divided into three groups and were administered intravenously with saline, free Chlorin e6 and Chlorin e6 NPs (5mg/kg Chlorin e6) once every 2 days for 2 weeks. The laser was applied three times 24h post injection (680 nm, 0.5 W/cm²for 5 min). Chlorin e6 NPs showed significantly enhanced anticancer benefits compared to free Chlorin e6, which almost obtained full ablation of tumours at the end of the study^[5]

References:
[1].Ryu AR, Kim YW, et al. Chlorin e6-mediated photodynamic therapy modulates adipocyte differentiation and lipogenesis in 3T3-L1 cells. Photodiagnosis Photodyn Ther. 2020;31:101917.
[2].Papayan G.V., Akopov А.L. Photodynamic theranostics of central lung cancer: capabilities of early diagnosis and minimally invasive therapy (review). Sovremennye tehnologii v medicine 2021; 13(6): 78
[3].Karuppusamy S, Hyejin K, et al. Nanoengineered chlorin e6 conjugated with hydrogel for photodynamic therapy on cancer. Colloids Surf B Biointerfaces. 2019;181:778-788.
[4].Park C, Yoo J, et al. Chlorin e6-Loaded PEG-PCL Nanoemulsion for Photodynamic Therapy and In Vivo Drug Delivery. Int J Mol Sci. 2019;20(16):3958. Published 2019 Aug 14.
[5].Miao Z, Wang Y, et al. One-pot synthesis chlorin e6 nano-precipitation for colorectal cancer treatment Ce6 NPs for colorectal cancer treatment. IET Nanobiotechnol. 2021;15(8):680-685.