Green Synthesis of Silver Nanoparticles Using Carica Papaya Leaf Extract and Its Anticancer Activities through Regulation of Microtubule Dynamics in Breast Cancer

Carica papaya (CP) is an herbaceous succulent plant extensively used in Asian folk medicine. CP leaves were utilized in the study for rapid eco-friendly biosynthesis of silver nanoparticles (CP-AgNP). The CP-AgNP obtained was spherical (scanning electron microscope images) with a size of 26.5 ± 3.45 nm as evident from transmission electron microscope images with a Zeta Potential of −50 mV. TNBC cell line MDA-MB 231 was treated with various doses of CP and CP-AgNP to determine the IC₅₀ values of 2.4 mg/mL and 15.13 µg/mL, respectively. Cell cycle analysis disclosed a G2/M arrest upon administration of the treatments. The tubulin depolymerization potential of the treatments affirmed perturbation of tubulin polymerization instigated the apoptosis by ROS induction. Further testing of the treatments in an in vivo and patient-derived ex vivo culture platform elicited tumor growth reduction. The current study identified a few probable tubulin-disrupting candidates in our crude CP extract through molecular docking. Some of the major challenges of the cancer drug delivery addressed by our nanoformulation are increased stability, higher levels of biocompatibility, and reduced toxicity. Our data supports that modifications coupled with targeted delivery of CP-AgNP can act as a novel anticancer therapeutic.