Abstract
Acute myeloid leukemia (AML) remains one of the most aggressive and treatment-resistant hematologic malignancies, driven by clonal expansion of immature myeloid blasts in the bone marrow and peripheral blood. Current therapies-chemotherapy and targeted agents-are limited by poor marrow penetration, systemic toxicity, and rapid development of resistant clones, leaving long-term survival rates low. Clinicians face the persistent challenge of delivering effective therapy while minimizing harm. Platelets and neutrophils-beyond their classical roles in hemostasis and innate immunity-actively support leukemic niches, suppress anti-tumor immunity, and protect malignant cells from cytotoxic attack. These interactions highlight an untapped opportunity: harnessing endogenous cellular networks to deliver therapeutics with precision and potency. Conventional carriers, including liposomes and nanoparticles, fail to exploit these natural trafficking and immune-modulatory mechanisms, limiting marrow-specific targeting and therapeutic durability. We propose cellular hitchhiking using patient-derived platelets and neutrophils as a transformative, patient-tailored strategy. These carriers leverage intrinsic homing mechanisms, immune interface modulation, and prolonged circulation to deliver cytotoxic, immunomodulatory, or gene-based therapeutics directly to marrow and sanctuary sites. Ex vivo priming, biomaterial functionalization, and patient-specific engineering can enhance marrow-targeted drug concentration by several-fold, reduce systemic exposure, and minimize thrombo-inflammatory complications. By converting circulating blood cells into programmable delivery vectors, this approach offers a biologically rational platform with translational potential; however, immediate clinical relevance requires validation in controlled early-phase human studies. Preclinical evidence indicates that cellular hitchhiking can substantially increase bone-marrow drug delivery and reduce systemic exposure; whether these improvements will translate into higher remission rates or lower relapse in patients remains to be established in prospective clinical studies. Integrated into AML management, this strategy provides a biologically rational platform with translational potential; careful preclinical de-risking and early-phase clinical trials are required to determine clinical relevance.