A new cannabigerol derivative, LE-127/2, induces autophagy mediated cell death in human cutaneous melanoma cells
Ágnes Tósaki1, Zsuzsanna Szabó2, József Király2
1Department of Dermatology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary.
Abstract:
Despite the targeted- and immunotherapies used in the past decade, survival rate among patients with metastatic melanoma remains low, therefore, melanoma is responsible for the majority of skin cancer-related deaths. The ongoing investigation of natural antitumor agents, the nonpsychoactive cannabinoid, cannabigerol (CBG) found in Cannabis sativa is emerging as a promising candidate. CBG offers a potential therapeutic role in the treatment of melanoma demonstrating cell growth inhibition in some tumors. Its low water solubility and bioavailability hinder the potential effectiveness. To address these challenges, a modified CBG, namely LE-127/2 was synthesized by Mannich-type reaction. The aim was to investigate the effect of this novel compound on cell proliferation as well as the mechanism of cell death with a particular focus on autophagy and apoptosis. Human cutan melanoma cell lines, WM35, A2058 and WM3000 were utilized for the present study. Cell proliferation of the cells after the treatment with LE-127/2, parent CBG or vemurafenib was assessed by Cell Titer Blue Assay. Cells were treated with a 1.25-80 µM of the above-mentioned compounds, and it was found that at 20 μM of all drugs showed a comparable effective inhibition of cell proliferation, however, vemurafenib and CBG proved to be more effective than LE-127/2. In addition, clonogenic cell survival assays were performed to examine the inhibitory effect of LE-127/2 on the colony formation ability of melanoma cell lines. Cells treated with 20 µM of LE-127/2 for 14 days showed about a 50% suppression of clonogenic cell survival. LE-127/2 exerted the most intensive inhibition on A2058 cell colonies. Furthermore, notably, LDH cytotoxicity assay performed on HaCaT cell line, proved LE-127/2 to be cytotoxic only at higher concentration, such as 80 μM, while the parent CBG was cytotoxic at concentration as low as 5 μM, suggesting that the new CBG derivative as a drug candidate may be applied in human pharmacotherapy without causing a substantial damage in intact epidermal cells. Analysis of protein expression revealed the impact of LE-127/2 on the expression of basic proteins (LC-3, Beclin-1 and p62) involved in the process of autophagy in the three different melanoma cell lines studied. Elevated expression of these proteins was detected as a result of LE-127/2 (20 µM) treatment. LE-127/2 also induced the expression of some proteins involved in apoptosis, and it is particularly noteworthy the increased level of cleaved PARP. Based on the results obtained, it can be concluded that LE-127/2 induced autophagy could lead to the inhibition of cell proliferation and death in melanoma cells.
Insights
A novel cannabigerol (CBG) derivative, LE-127/2, shows potential in treating melanoma by inhibiting cancer cell growth and survival. This compound induces autophagy and apoptosis, offering a promising therapeutic avenue with reduced cytotoxicity compared to parent CBG.
Area of Science:
- Oncology
- Pharmacology
- Cannabinoid Research
Background:
- Metastatic melanoma survival rates remain low despite advancements in targeted and immunotherapies.
- Cannabigerol (CBG), a nonpsychoactive cannabinoid from Cannabis sativa, exhibits antitumor properties but suffers from poor solubility and bioavailability.
- A modified CBG derivative, LE-127/2, was synthesized to overcome these limitations for potential melanoma treatment.
Purpose of the Study:
- To investigate the effects of the novel CBG derivative, LE-127/2, on melanoma cell proliferation.
- To elucidate the mechanism of cell death induced by LE-127/2, focusing on autophagy and apoptosis.
- To assess the therapeutic potential and safety profile of LE-127/2 compared to parent CBG and vemurafenib.
Main Methods:
- Human melanoma cell lines (WM35, A2058, WM3000) were treated with LE-127/2, CBG, or vemurafenib.
- Cell proliferation was assessed using Cell Titer Blue Assay and clonogenic survival assays.
- Cytotoxicity was evaluated using LDH assay on HaCaT cells, and protein expression related to autophagy and apoptosis was analyzed.
Main Results:
- LE-127/2, CBG, and vemurafenib showed comparable cell proliferation inhibition at 20 µM, though vemurafenib and CBG were more effective.
- LE-127/2 significantly suppressed clonogenic survival by approximately 50% in melanoma cells, with the strongest effect on A2058 cells.
- LE-127/2 demonstrated lower cytotoxicity on normal HaCaT cells compared to CBG, and induced autophagy and apoptosis markers (LC-3, Beclin-1, p62, cleaved PARP) in melanoma cells.
Conclusions:
- LE-127/2 effectively inhibits melanoma cell proliferation and clonogenic survival, indicating its potential as an anticancer agent.
- The compound induces cell death through autophagy and apoptosis pathways in melanoma cells.
- LE-127/2 exhibits a favorable safety profile with reduced cytotoxicity on normal epidermal cells, suggesting its viability for human pharmacotherapy.
