AC3TM Reduces Cell Proliferation and Migration by Modulating the TNF/TNFR1 Axis and Improves the Immune Response by Downregulating CD39/CD73/Ado in Cutaneous Melanoma Cell Lines

Background/Objectives: Cutaneous melanoma (CM) poses a critical public health concern due to its high recurrence rates and resistance to standard treatments. This study investigated the antineoplastic potential of Curcuma Longa L. extract enriched with Bisdemethoxycurcumin (AC3TM) on human melanoma cell lines A375 and SK-MEL-28. Methods: The A375 and SK-MEL-28 cell lines were cultured according to the manufacturer's recommendations and were subsequently treated with different concentrations of AC3TM. The MTT test and fluorescence microscopy were used to assess cell viability. The wound healing assay was used to verify cell migration after treatment with the compound. To determine reactive oxygen species (ROS) levels, we used the fluorescence assay with 2,7-dichlorodihydrofluorescein diacetate. Subsequently, the molecular pathways associated with apoptosis were evaluated using RT-PCR, including the modulation of the inflammatory profile and the components of purinergic signaling. Results: The results revealed that AC3™ effectively inhibited cell proliferation and migration in both melanoma cell lines. In A375 cells, the compound reduced ROS levels and significantly modulated apoptotic pathways, including upregulation of caspase-3 expression. Similarly, in SK-MEL-28 cells, increased expression of caspase-8 and caspase-3 indicated the activation of both intrinsic and extrinsic apoptotic mechanisms. Additionally, AC3™ influenced the inflammatory response by increasing the expression of Tumor Necrosis Factor Alpha (TNF-α), Interleukin 6 (IL-6) and NLR Family Pyrin Domain Containing 3 (NLRP3) in A375 cells while downregulating NLRP3 expression in SK-MEL-28 cells, highlighting its differential immune modulatory effects. Furthermore, the compound modulates the expression and enzymatic activity of ecto-nucleoside triphosphate diphosphohydrolase 1 (CD39) and ecto-5'-nucleotidase (CD73), key regulators of purinergic signaling, suggesting its ability to impact immune evasion mechanisms in melanoma. Conclusions: These findings position AC3™ as a promising therapeutic candidate for melanoma, targeting critical pathways related to tumor progression, immune regulation, and cellular survival.