Potent cytotoxicity of plumbagin targets human glioblastoma and colorectal carcinoma.

Plumbagin (Plb) is a potent cytotoxic compound derived from Plumbago scandens L. Pharmacological investigations have demonstrated its broad-spectrum biological activities, including anticancer, antifungal, anti-inflammatory, antibacterial, antidiabetic, and antioxidant properties. In the present study, we aimed to determine the cytotoxic effects of Plb in glioblastoma and colorectal carcinoma cells. The human cell lines U-87 MG (glioblastoma), RKO-AS45-1 (colorectal carcinoma), and WI26 VA4 (lung epithelial) were used in this study. Cytotoxic effects were evaluated in 2D cell cultures, and in U-87 MG glioblastoma spheroids, using the MTT assay. Cell migration and antiproliferative activity were assessed using migration and clonogenic assays, respectively. Cellular damage was analyzed by confocal microscopy. Plb exhibited significant cytotoxicity at a concentration of 10 μg/mL after 24 hours, reducing the cell viability of 28.3% in U-87 MG cells, 28.8% in RKO-AS45-1 cells, and 14.1% in WI26 VA4 cells, as determined by the MTT assay. While no significant changes in wound thickness were observed in RKO and WI26 cell lines, Plb treatment severely disrupted cell migration and adhesion in U-87 MG cells. Plb at IC50 concentration showed surviving fractions of clonogenic assays of 1.1% in U-87 MG cells, 0.5% in RKO-AS45-1 cells, and 0.2% in WI26 VA4 cells, revealing notable antiproliferative effects. Analysis of U87 MG 3D spheroids confirmed that Plb markedly disrupted cell-cell adhesion and impaired cell migration.Confocal microscopic evaluation revealed cellular damage characterized by cytoskeletal disruption, vacuolation, and mitochondrial dysfunction. In conclusion, Plb exhibits significant cytotoxicity and potential antitumor activity.