Target selectivity of cholesterol-phosphatidylcholine liposome loaded with phthalocyanine for breast cancer diagnosis and treatment by photodynamic therapy.

This study investigated the ability of cholesterol-phosphatidylcholine liposomes loaded with chloride aluminum phthalocyanine (CL-AlClPc) to discriminate between healthy (MCF-10A) and neoplastic (MCF-7 and MDA-MB-231) breast cells for breast cancer diagnosis and treatment by photodynamic therapy (PDT) using a new drug delivery system consisting of CL-AlClPc. When PDT treatment was applied at an energy fluence of 700 mJ/cm², CL-AlClPc was more cytotoxic to neoplastic cells than to healthy breast cells because CL-AlClPc was better internalized by the tumor cells. An even higher fluorescence signal is expected for neoplastic cells during clinical treatment than for healthy cells, which will be useful for precise and targeted tumor cell detection. CL-AlClPc also facilitated better drug distribution and targeting of essential organelles inside the cells. This selectivity is critical for future in vivo diagnosis and treatment; it prevents side effects because it prioritizes tumor cells and tissues instead of healthy ones. The CL-AlClPc system designed herein had a small size (150 nm), low zeta potential (-6 mV), low polydispersity (0.16), high encapsulation rate efficiency (82.83%), and high shelf stability (12 months).

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 .

Standardization of a resazurin-based assay for the evaluation of metabolic activity in oral squamous carcinoma and glioblastoma cells.

The widely accepted resazurin-based assay can be used, prior to in vivo studies, as an inexpensive method to determine cytotoxicity. The aim of this study was to evaluate and standardize the assay conditions for oral squamous cancer cell (OSCC) and glioblastoma (U87-MG) lines by UV-vis spectroscopy. The cells were treated with 25 µgmL-1 of resazurin sodium salt and then incubated for 4 h, 6 h, and 6.5 h. All absorbance measurements were carried out at 21 ± 1 °C on a spectrophotometer with a microplate reader. After 4-hs of incubation, resazurin was completely reduced by OSCC cells, as demonstrated by the suppression of the absorbance at 380 nm. However, the U87-MG cells needed 6.5 h of incubation to demonstrate the same behavior. The Statistical analysis did not indicate significant differences between the OSCC and U87-MG cell lines' viability after 4 and 6.5 h respectively. We concluded that spectroscopic analysis is an efficient method for the standardization of the resazurin assay. In addition, without the implementation of suitable protocols, there could be an increase in the chance of errors or false positives or negatives that would reduce the usefulness of the data.