Bioinspired Photoresponsive Algosomes as a Nanocarrier for Combating Cancer and Bacterial Infections

The interplay between cancer and bacteria is a complex and evolving area of study, with certain bacteria implicated in both cancer onset and elicitation of chemoresistance. Combining nanoparticle-based photodynamic therapy (PDT) with antibiotics is a powerful strategy to overcome bacteria-induced chemoresistance in tumors. This synergistic approach enhances targeting and killing of both cancer cells and bacteria with a prompting immune response. In this study, we have synthesized uniform spherical shaped, self-assembled chlorophyll-rich, fluorescent, and photosensitive nanocarriers (named algosomes), derived from cyanobacterium, Spirulina platensis. These algosomes specifically target cancer cells due to an abundance of polyunsaturated fatty acids (PUFA) which are taken up more by the cancer cells to maintain cell membrane phospholipids to support their rapid growth and survival and exhibit tumor suppression via PDT due to integrated chlorophyll. Additionally, they serve as an excellent drug delivery system for antibiotics, enhancing the antibacterial activity against multidrug-resistant bacteria. Comprehensive biocompatibility evaluations on L929 cell lines, hemocompatibility tests, and in ovo biocompatibility studies in zebrafish embryos validated the safety of algosomes for potential clinical applications. In vitro findings demonstrated that algosomes in response to near-infrared (NIR) light kill cancer cells by inducing oxidative stress and mitochondrial damage, which leads to apoptosis in skin and colon cancer. Photoresponsive algosomes also impede cell migration following treatment, a crucial factor in preventing metastasis. Furthermore, the antibacterial and antihemolytic effect of antibiotic-loaded algosomes against multidrug resistant Escherichia coli and Staphylococcus aureus was quantified. This nanocarrier addresses the complex interplay of bacterial infections and cancer within a single nanoplatform, offering a promising solution to combat these dual challenges. Continued research and clinical development of this combination therapy hold promise for more effective and comprehensive cancer treatments.