Malignant melanoma is one of the most aggressive and lethal forms of skin cancer, posing a significant global health challenge. Despite therapeutic advances, current treatment strategies remain limited in efficacy, highlighting the need for alternative approaches. Photodynamic therapy (PDT) is a minimally invasive treatment that uses a photosensitizer activated by specific light wavelengths to generate reactive oxygen species (ROS), leading to targeted destruction of cancer cells. Curcumin, a natural phenolic compound derived from Curcuma longa, possesses diverse pharmacological properties, including anticancer activity, and has emerged as a potential photosensitizer. This study aimed to evaluate the in vitro efficacy of curcumin-mediated PDT in inducing cytotoxic effects in metastatic melanoma (A375) cells. A375 cells were treated with curcumin followed by irradiation using a 405 nm laser at fluence levels of 5 and 15 J/cm². Post-irradiation incubation was conducted for 24 and 48 h. Cellular responses were assessed via ROS detection assays, nuclear damage evaluation (using nuclear staining), apoptosis assays, morphological observation, and cell viability tests. Curcumin-PDT treatment induced a fluence- and time-dependent increase in intracellular ROS levels. Treated cells exhibited marked nuclear fragmentation, reduced viability, morphological alterations, and significant apoptosis compared to control groups. The extent of these effects correlated with both laser fluence and incubation time. These findings confirm that curcumin, upon photoactivation, induces oxidative stress and apoptosis in melanoma cells, thereby reducing cell survival. These results support the potential of curcumin as a natural photosensitizer in PDT and suggest its promising application in nanobioconjugate delivery systems for melanoma therapy.
A. Obalola, Heidi Abrahamse, S. S. Dhilip Kumar· Cancer Treatment and Researc...· 0 citations
The escalating global cancer burden, particularly in low- and middle-income countries, necessitates safer and more effective therapeutic strategies. The toxicity and environmental issues of traditional heavy-metal-based quantum dots (QDs) have been addressed by green-synthesised QDs, which have become a promising platform for nanomedicine. In photodynamic treatment (PDT), photothermal therapy (PTT), and theranostic applications, the anticancer effectiveness of green-synthesized QDs that are derived from plant extracts, microbes, biomolecules, and biomass waste is critically assessed. Green synthesis techniques, such as hydrothermal and microwave-assisted methods, provide biocompatible QDs with good photostability, tunable optical characteristics, and decreased cytotoxicity. Mechanistically, these QDs generate reactive oxygen species (ROS), induce mitochondrial dysfunction, produce localized hyperthermia upon near-infrared irradiation, and activate apoptotic pathways (such as p53, Bax/Bcl-2, and caspase cascade), leading to selective cancer cell death. Preclinical in vitro and in vivo studies demonstrate potent tumor ablation through passive (EPR effect) and active targeting strategies. Despite these advances, some key setbacks hinder their clinical translation: lack of standardized synthesis protocols, batch-to-batch variability, limited long-term biosafety data, suboptimal targeting efficiency, and regulatory hurdles. Future perspectives include AI-driven optimization, smart theranostic platforms integrating multimodal imaging and therapy, and sustainable circular economy approaches using biowaste. Addressing these challenges through harmonized protocols and rigorous preclinical validation will be essential to realize the full potential of green-synthesized QDs as safe, multifunctional, and effective cancer nanomedicines.
G. Kah, Heidi Abrahamse· RSC Advances· 0 citations