Development of DNA polymer films as a drug delivery system for the treatment of oral cancer.

DNA polymer films (DNA-PFs) hold promise for use in drug delivery systems (DDS). In this study, the growth pattern of oral squamous cell carcinoma (OSCC) cells was evaluated on DNA-PFs incorporated with a photoactive compound chlorine aluminum phthalocyanine (DNA-PFs-AlClPc) and the efficacy of DNA-PFs-AlClPc as a DDS for photodynamic therapy (PDT) for the treatment of mucosal cancer. Flow cytometry was used to evaluate cell viability following application of DNA-PFs-AlClPc during PDT; the results demonstrated a positive response to photo stimulation within the range of light doses used (300, 600, and 1200 mJ/cm2). Reduced viability and increased cell death were observed with increasing doses than in the controls. As expected, the viability was reduced by more than 30% at the highest dose (1200 mJ/cm2). Flow cytometry revealed that the main mechanism of cell death induction was apoptosis (early and late apoptosis). These results demonstrate the potential of applying DNA-PFs-AlClPc as a DDS for other active molecules in the treatment of other pathologies. Furthermore, this system allows other drugs to be associated with DNA-PFs, indicating the potential use of this nanostructure in novel ways for the treatment of different neoplasms, such as oral cancer. Additionally, DNA nanostructured films may be used to support cell growth and subsequently as a "curative material" incorporated with an active or photoactive compound that can induce tissue regeneration. Graphical abstract .